From 708bbb45537780a8d3721ca1e0cf1932c1d1bf5f Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 3 Mar 2026 15:03:39 +0100 Subject: wifi: mac80211: remove keys after disabling beaconing We shouldn't remove keys before disable beaconing, at least when beacon protection is used, since that would remove keys that are still used for beacon transmission at the same time. Stop before removing keys so there's no race. Fixes: af2d14b01c32 ("mac80211: Beacon protection using the new BIGTK (STA)") Reviewed-by: Miriam Rachel Korenblit Link: https://patch.msgid.link/20260303150339.574e7887b3ab.I50d708f5aa22584506a91d0da7f8a73ba39fceac@changeid Signed-off-by: Johannes Berg --- net/mac80211/cfg.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index b92b4a5c2636..b85375ceb575 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1904,12 +1904,6 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev, __sta_info_flush(sdata, true, link_id, NULL); - ieee80211_remove_link_keys(link, &keys); - if (!list_empty(&keys)) { - synchronize_net(); - ieee80211_free_key_list(local, &keys); - } - ieee80211_stop_mbssid(sdata); RCU_INIT_POINTER(link_conf->tx_bss_conf, NULL); @@ -1921,6 +1915,12 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev, ieee80211_link_info_change_notify(sdata, link, BSS_CHANGED_BEACON_ENABLED); + ieee80211_remove_link_keys(link, &keys); + if (!list_empty(&keys)) { + synchronize_net(); + ieee80211_free_key_list(local, &keys); + } + if (sdata->wdev.links[link_id].cac_started) { chandef = link_conf->chanreq.oper; wiphy_hrtimer_work_cancel(wiphy, &link->dfs_cac_timer_work); -- cgit v1.2.3 From ac6f24cc9c0a9aefa55ec9696dcafa971d4d760b Mon Sep 17 00:00:00 2001 From: Nicolas Cavallari Date: Tue, 3 Mar 2026 17:06:39 +0100 Subject: wifi: mac80211: use jiffies_delta_to_msecs() for sta_info inactive times Inactive times of around 0xffffffff milliseconds have been observed on an ath9k device on ARM. This is likely due to a memory ordering race in the jiffies_to_msecs(jiffies - last_active()) calculation causing an overflow when the observed jiffies is below ieee80211_sta_last_active(). Use jiffies_delta_to_msecs() instead to avoid this problem. Fixes: 7bbdd2d98797 ("mac80211: implement station stats retrieval") Signed-off-by: Nicolas Cavallari Link: https://patch.msgid.link/20260303161701.31808-1-nicolas.cavallari@green-communications.fr Signed-off-by: Johannes Berg --- net/mac80211/sta_info.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 6dc22f1593be..dd51a578fbc5 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -2782,7 +2782,9 @@ static void sta_set_link_sinfo(struct sta_info *sta, } link_sinfo->inactive_time = - jiffies_to_msecs(jiffies - ieee80211_sta_last_active(sta, link_id)); + jiffies_delta_to_msecs(jiffies - + ieee80211_sta_last_active(sta, + link_id)); if (!(link_sinfo->filled & (BIT_ULL(NL80211_STA_INFO_TX_BYTES64) | BIT_ULL(NL80211_STA_INFO_TX_BYTES)))) { @@ -3015,7 +3017,8 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo, sinfo->connected_time = ktime_get_seconds() - sta->last_connected; sinfo->assoc_at = sta->assoc_at; sinfo->inactive_time = - jiffies_to_msecs(jiffies - ieee80211_sta_last_active(sta, -1)); + jiffies_delta_to_msecs(jiffies - + ieee80211_sta_last_active(sta, -1)); if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_TX_BYTES64) | BIT_ULL(NL80211_STA_INFO_TX_BYTES)))) { -- cgit v1.2.3 From 672e5229e1ecfc2a3509b53adcb914d8b024a853 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 5 Mar 2026 17:08:12 +0000 Subject: mac80211: fix crash in ieee80211_chan_bw_change for AP_VLAN stations ieee80211_chan_bw_change() iterates all stations and accesses link->reserved.oper via sta->sdata->link[link_id]. For stations on AP_VLAN interfaces (e.g. 4addr WDS clients), sta->sdata points to the VLAN sdata, whose link never participates in chanctx reservations. This leaves link->reserved.oper zero-initialized with chan == NULL, causing a NULL pointer dereference in __ieee80211_sta_cap_rx_bw() when accessing chandef->chan->band during CSA. Resolve the VLAN sdata to its parent AP sdata using get_bss_sdata() before accessing link data. Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau Link: https://patch.msgid.link/20260305170812.2904208-1-nbd@nbd.name [also change sta->sdata in ARRAY_SIZE even if it doesn't matter] Signed-off-by: Johannes Berg --- net/mac80211/chan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 4447cf03c41b..05f45e66999b 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -561,14 +561,16 @@ static void ieee80211_chan_bw_change(struct ieee80211_local *local, rcu_read_lock(); list_for_each_entry_rcu(sta, &local->sta_list, list) { - struct ieee80211_sub_if_data *sdata = sta->sdata; + struct ieee80211_sub_if_data *sdata; enum ieee80211_sta_rx_bandwidth new_sta_bw; unsigned int link_id; if (!ieee80211_sdata_running(sta->sdata)) continue; - for (link_id = 0; link_id < ARRAY_SIZE(sta->sdata->link); link_id++) { + sdata = get_bss_sdata(sta->sdata); + + for (link_id = 0; link_id < ARRAY_SIZE(sdata->link); link_id++) { struct ieee80211_link_data *link = rcu_dereference(sdata->link[link_id]); struct ieee80211_bss_conf *link_conf; -- cgit v1.2.3 From b94ae8e0d5fe1bdbbfdc3854ff6ce98f6876a828 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Fri, 6 Mar 2026 07:24:02 +0000 Subject: wifi: mac80211: Fix static_branch_dec() underflow for aql_disable. syzbot reported static_branch_dec() underflow in aql_enable_write(). [0] The problem is that aql_enable_write() does not serialise concurrent write()s to the debugfs. aql_enable_write() checks static_key_false(&aql_disable.key) and later calls static_branch_inc() or static_branch_dec(), but the state may change between the two calls. aql_disable does not need to track inc/dec. Let's use static_branch_enable() and static_branch_disable(). [0]: val == 0 WARNING: kernel/jump_label.c:311 at __static_key_slow_dec_cpuslocked.part.0+0x107/0x120 kernel/jump_label.c:311, CPU#0: syz.1.3155/20288 Modules linked in: CPU: 0 UID: 0 PID: 20288 Comm: syz.1.3155 Tainted: G U L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:__static_key_slow_dec_cpuslocked.part.0+0x107/0x120 kernel/jump_label.c:311 Code: f2 c9 ff 5b 5d c3 cc cc cc cc e8 54 f2 c9 ff 48 89 df e8 ac f9 ff ff eb ad e8 45 f2 c9 ff 90 0f 0b 90 eb a2 e8 3a f2 c9 ff 90 <0f> 0b 90 eb 97 48 89 df e8 5c 4b 33 00 e9 36 ff ff ff 0f 1f 80 00 RSP: 0018:ffffc9000b9f7c10 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffffffff9b3e5d40 RCX: ffffffff823c57b4 RDX: ffff8880285a0000 RSI: ffffffff823c5846 RDI: ffff8880285a0000 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000000a R13: 1ffff9200173ef88 R14: 0000000000000001 R15: ffffc9000b9f7e98 FS: 00007f530dd726c0(0000) GS:ffff8881245e3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001140 CR3: 000000007cc4a000 CR4: 00000000003526f0 Call Trace: __static_key_slow_dec_cpuslocked kernel/jump_label.c:297 [inline] __static_key_slow_dec kernel/jump_label.c:321 [inline] static_key_slow_dec+0x7c/0xc0 kernel/jump_label.c:336 aql_enable_write+0x2b2/0x310 net/mac80211/debugfs.c:343 short_proxy_write+0x133/0x1a0 fs/debugfs/file.c:383 vfs_write+0x2aa/0x1070 fs/read_write.c:684 ksys_pwrite64 fs/read_write.c:793 [inline] __do_sys_pwrite64 fs/read_write.c:801 [inline] __se_sys_pwrite64 fs/read_write.c:798 [inline] __x64_sys_pwrite64+0x1eb/0x250 fs/read_write.c:798 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f530cf9aeb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f530dd72028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f530d215fa0 RCX: 00007f530cf9aeb9 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000010 RBP: 00007f530d008c1f R08: 0000000000000000 R09: 0000000000000000 R10: 4200000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f530d216038 R14: 00007f530d215fa0 R15: 00007ffde89fb978 Fixes: e908435e402a ("mac80211: introduce aql_enable node in debugfs") Reported-by: syzbot+feb9ce36a95341bb47a4@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69a8979e.a70a0220.b118c.0025.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260306072405.3649474-1-kuniyu@google.com Signed-off-by: Johannes Berg --- net/mac80211/debugfs.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) (limited to 'net') diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index d02f07368c51..687a66cd4943 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -320,7 +320,6 @@ static ssize_t aql_enable_read(struct file *file, char __user *user_buf, static ssize_t aql_enable_write(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { - bool aql_disabled = static_key_false(&aql_disable.key); char buf[3]; size_t len; @@ -335,15 +334,12 @@ static ssize_t aql_enable_write(struct file *file, const char __user *user_buf, if (len > 0 && buf[len - 1] == '\n') buf[len - 1] = 0; - if (buf[0] == '0' && buf[1] == '\0') { - if (!aql_disabled) - static_branch_inc(&aql_disable); - } else if (buf[0] == '1' && buf[1] == '\0') { - if (aql_disabled) - static_branch_dec(&aql_disable); - } else { + if (buf[0] == '0' && buf[1] == '\0') + static_branch_enable(&aql_disable); + else if (buf[0] == '1' && buf[1] == '\0') + static_branch_disable(&aql_disable); + else return -EINVAL; - } return count; } -- cgit v1.2.3 From 6dccbc9f3e1d38565dff7730d2b7d1e8b16c9b09 Mon Sep 17 00:00:00 2001 From: Peddolla Harshavardhan Reddy Date: Thu, 5 Mar 2026 21:36:59 +0530 Subject: wifi: cfg80211: cancel pmsr_free_wk in cfg80211_pmsr_wdev_down When the nl80211 socket that originated a PMSR request is closed, cfg80211_release_pmsr() sets the request's nl_portid to zero and schedules pmsr_free_wk to process the abort asynchronously. If the interface is concurrently torn down before that work runs, cfg80211_pmsr_wdev_down() calls cfg80211_pmsr_process_abort() directly. However, the already- scheduled pmsr_free_wk work item remains pending and may run after the interface has been removed from the driver. This could cause the driver's abort_pmsr callback to operate on a torn-down interface, leading to undefined behavior and potential crashes. Cancel pmsr_free_wk synchronously in cfg80211_pmsr_wdev_down() before calling cfg80211_pmsr_process_abort(). This ensures any pending or in-progress work is drained before interface teardown proceeds, preventing the work from invoking the driver abort callback after the interface is gone. Fixes: 9bb7e0f24e7e ("cfg80211: add peer measurement with FTM initiator API") Signed-off-by: Peddolla Harshavardhan Reddy Link: https://patch.msgid.link/20260305160712.1263829-3-peddolla.reddy@oss.qualcomm.com Signed-off-by: Johannes Berg --- net/wireless/pmsr.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/wireless/pmsr.c b/net/wireless/pmsr.c index 44bd88c9ea66..50e8e19aa366 100644 --- a/net/wireless/pmsr.c +++ b/net/wireless/pmsr.c @@ -664,6 +664,7 @@ void cfg80211_pmsr_wdev_down(struct wireless_dev *wdev) } spin_unlock_bh(&wdev->pmsr_lock); + cancel_work_sync(&wdev->pmsr_free_wk); if (found) cfg80211_pmsr_process_abort(wdev); -- cgit v1.2.3 From e1d9a66889867c232657a9b6f25d451d7c3ab96f Mon Sep 17 00:00:00 2001 From: Christian Eggers Date: Wed, 25 Feb 2026 18:07:25 +0100 Subject: Bluetooth: LE L2CAP: Disconnect if received packet's SDU exceeds IMTU Core 6.0, Vol 3, Part A, 3.4.3: "If the SDU length field value exceeds the receiver's MTU, the receiver shall disconnect the channel..." This fixes L2CAP/LE/CFC/BV-26-C (running together with 'l2test -r -P 0x0027 -V le_public -I 100'). Fixes: aac23bf63659 ("Bluetooth: Implement LE L2CAP reassembly") Signed-off-by: Christian Eggers Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index ad98db9632fd..3056dcd5fa2f 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -6662,8 +6662,10 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) return -ENOBUFS; } - if (chan->imtu < skb->len) { - BT_ERR("Too big LE L2CAP PDU"); + if (skb->len > chan->imtu) { + BT_ERR("Too big LE L2CAP PDU: len %u > %u", skb->len, + chan->imtu); + l2cap_send_disconn_req(chan, ECONNRESET); return -ENOBUFS; } @@ -6689,7 +6691,9 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) sdu_len, skb->len, chan->imtu); if (sdu_len > chan->imtu) { - BT_ERR("Too big LE L2CAP SDU length received"); + BT_ERR("Too big LE L2CAP SDU length: len %u > %u", + skb->len, sdu_len); + l2cap_send_disconn_req(chan, ECONNRESET); err = -EMSGSIZE; goto failed; } -- cgit v1.2.3 From b6a2bf43aa37670432843bc73ae2a6288ba4d6f8 Mon Sep 17 00:00:00 2001 From: Christian Eggers Date: Wed, 25 Feb 2026 18:07:27 +0100 Subject: Bluetooth: LE L2CAP: Disconnect if sum of payload sizes exceed SDU Core 6.0, Vol 3, Part A, 3.4.3: "... If the sum of the payload sizes for the K-frames exceeds the specified SDU length, the receiver shall disconnect the channel." This fixes L2CAP/LE/CFC/BV-27-C (running together with 'l2test -r -P 0x0027 -V le_public'). Fixes: aac23bf63659 ("Bluetooth: Implement LE L2CAP reassembly") Signed-off-by: Christian Eggers Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 3056dcd5fa2f..0f400051f093 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -6729,6 +6729,7 @@ static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb) if (chan->sdu->len + skb->len > chan->sdu_len) { BT_ERR("Too much LE L2CAP data received"); + l2cap_send_disconn_req(chan, ECONNRESET); err = -EINVAL; goto failed; } -- cgit v1.2.3 From 0e4d4dcc1a6e82cc6f9abf32193558efa7e1613d Mon Sep 17 00:00:00 2001 From: Christian Eggers Date: Wed, 25 Feb 2026 18:07:28 +0100 Subject: Bluetooth: SMP: make SM/PER/KDU/BI-04-C happy The last test step ("Test with Invalid public key X and Y, all set to 0") expects to get an "DHKEY check failed" instead of "unspecified". Fixes: 6d19628f539f ("Bluetooth: SMP: Fail if remote and local public keys are identical") Signed-off-by: Christian Eggers Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index e67bf7b34ea7..485e3468bd26 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -2743,7 +2743,7 @@ static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) if (!test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags) && !crypto_memneq(key, smp->local_pk, 64)) { bt_dev_err(hdev, "Remote and local public keys are identical"); - return SMP_UNSPECIFIED; + return SMP_DHKEY_CHECK_FAILED; } memcpy(smp->remote_pk, key, 64); -- cgit v1.2.3 From 62bcaa6b351b6dc400f6c6b83762001fd9f5c12d Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Fri, 27 Feb 2026 15:23:01 -0500 Subject: Bluetooth: ISO: Fix defer tests being unstable iso-tester defer tests seem to fail with hci_conn_hash_lookup_cig being unable to resolve a cig in set_cig_params_sync due a race where it is run immediatelly before hci_bind_cis is able to set the QoS settings into the hci_conn object. So this moves the assigning of the QoS settings to be done directly by hci_le_set_cig_params to prevent that from happening again. Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections") Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_conn.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 4719dac07190..6eb59e9f2aa8 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1944,6 +1944,8 @@ static bool hci_le_set_cig_params(struct hci_conn *conn, struct bt_iso_qos *qos) return false; done: + conn->iso_qos = *qos; + if (hci_cmd_sync_queue(hdev, set_cig_params_sync, UINT_PTR(qos->ucast.cig), NULL) < 0) return false; @@ -2013,8 +2015,6 @@ struct hci_conn *hci_bind_cis(struct hci_dev *hdev, bdaddr_t *dst, } hci_conn_hold(cis); - - cis->iso_qos = *qos; cis->state = BT_BOUND; return cis; -- cgit v1.2.3 From 2cabe7ff1001b7a197009cf50ba71701f9cbd354 Mon Sep 17 00:00:00 2001 From: Michael Grzeschik Date: Thu, 5 Mar 2026 14:50:52 +0100 Subject: Bluetooth: hci_sync: Fix hci_le_create_conn_sync While introducing hci_le_create_conn_sync the functionality of hci_connect_le was ported to hci_le_create_conn_sync including the disable of the scan before starting the connection. When this code was run non synchronously the immediate call that was setting the flag HCI_LE_SCAN_INTERRUPTED had an impact. Since the completion handler for the LE_SCAN_DISABLE was not immediately called. In the completion handler of the LE_SCAN_DISABLE event, this flag is checked to set the state of the hdev to DISCOVERY_STOPPED. With the synchronised approach the later setting of the HCI_LE_SCAN_INTERRUPTED flag has not the same effect. The completion handler would immediately fire in the LE_SCAN_DISABLE call, check for the flag, which is then not yet set and do nothing. To fix this issue and make the function call work as before, we move the setting of the flag HCI_LE_SCAN_INTERRUPTED before disabling the scan. Fixes: 8e8b92ee60de ("Bluetooth: hci_sync: Add hci_le_create_conn_sync") Signed-off-by: Michael Grzeschik Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_sync.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 121dbc8208ec..3166914b0d6c 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -6627,8 +6627,8 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data) * state. */ if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) { - hci_scan_disable_sync(hdev); hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED); + hci_scan_disable_sync(hdev); } /* Update random address, but set require_privacy to false so -- cgit v1.2.3 From 17f89341cb4281d1da0e2fb0de5406ab7c4e25ef Mon Sep 17 00:00:00 2001 From: Wang Tao Date: Fri, 27 Feb 2026 11:03:39 +0000 Subject: Bluetooth: MGMT: Fix list corruption and UAF in command complete handlers Commit 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") introduced mgmt_pending_valid(), which not only validates the pending command but also unlinks it from the pending list if it is valid. This change in semantics requires updates to several completion handlers to avoid list corruption and memory safety issues. This patch addresses two left-over issues from the aforementioned rework: 1. In mgmt_add_adv_patterns_monitor_complete(), mgmt_pending_remove() is replaced with mgmt_pending_free() in the success path. Since mgmt_pending_valid() already unlinks the command at the beginning of the function, calling mgmt_pending_remove() leads to a double list_del() and subsequent list corruption/kernel panic. 2. In set_mesh_complete(), the use of mgmt_pending_foreach() in the error path is removed. Since the current command is already unlinked by mgmt_pending_valid(), this foreach loop would incorrectly target other pending mesh commands, potentially freeing them while they are still being processed concurrently (leading to UAFs). The redundant mgmt_cmd_status() is also simplified to use cmd->opcode directly. Fixes: 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") Signed-off-by: Wang Tao Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/mgmt.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index a7238fd3b03b..d52238ce6a9a 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -2195,10 +2195,7 @@ static void set_mesh_complete(struct hci_dev *hdev, void *data, int err) sk = cmd->sk; if (status) { - mgmt_cmd_status(cmd->sk, hdev->id, MGMT_OP_SET_MESH_RECEIVER, - status); - mgmt_pending_foreach(MGMT_OP_SET_MESH_RECEIVER, hdev, true, - cmd_status_rsp, &status); + mgmt_cmd_status(cmd->sk, hdev->id, cmd->opcode, status); goto done; } @@ -5377,7 +5374,7 @@ static void mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev, mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_status(status), &rp, sizeof(rp)); - mgmt_pending_remove(cmd); + mgmt_pending_free(cmd); hci_dev_unlock(hdev); bt_dev_dbg(hdev, "add monitor %d complete, status %d", -- cgit v1.2.3 From dbf666e4fc9bdd975a61bf682b3f75cb0145eedd Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Thu, 5 Mar 2026 10:17:47 -0500 Subject: Bluetooth: HIDP: Fix possible UAF This fixes the following trace caused by not dropping l2cap_conn reference when user->remove callback is called: [ 97.809249] l2cap_conn_free: freeing conn ffff88810a171c00 [ 97.809907] CPU: 1 UID: 0 PID: 1419 Comm: repro_standalon Not tainted 7.0.0-rc1-dirty #14 PREEMPT(lazy) [ 97.809935] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 [ 97.809947] Call Trace: [ 97.809954] [ 97.809961] dump_stack_lvl (lib/dump_stack.c:122) [ 97.809990] l2cap_conn_free (net/bluetooth/l2cap_core.c:1808) [ 97.810017] l2cap_conn_del (./include/linux/kref.h:66 net/bluetooth/l2cap_core.c:1821 net/bluetooth/l2cap_core.c:1798) [ 97.810055] l2cap_disconn_cfm (net/bluetooth/l2cap_core.c:7347 (discriminator 1) net/bluetooth/l2cap_core.c:7340 (discriminator 1)) [ 97.810086] ? __pfx_l2cap_disconn_cfm (net/bluetooth/l2cap_core.c:7341) [ 97.810117] hci_conn_hash_flush (./include/net/bluetooth/hci_core.h:2152 (discriminator 2) net/bluetooth/hci_conn.c:2644 (discriminator 2)) [ 97.810148] hci_dev_close_sync (net/bluetooth/hci_sync.c:5360) [ 97.810180] ? __pfx_hci_dev_close_sync (net/bluetooth/hci_sync.c:5285) [ 97.810212] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810242] ? up_write (./arch/x86/include/asm/atomic64_64.h:87 (discriminator 5) ./include/linux/atomic/atomic-arch-fallback.h:2852 (discriminator 5) ./include/linux/atomic/atomic-long.h:268 (discriminator 5) ./include/linux/atomic/atomic-instrumented.h:3391 (discriminator 5) kernel/locking/rwsem.c:1385 (discriminator 5) kernel/locking/rwsem.c:1643 (discriminator 5)) [ 97.810267] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810290] ? rcu_is_watching (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/context_tracking.h:128 kernel/rcu/tree.c:752) [ 97.810320] hci_unregister_dev (net/bluetooth/hci_core.c:504 net/bluetooth/hci_core.c:2716) [ 97.810346] vhci_release (drivers/bluetooth/hci_vhci.c:691) [ 97.810375] ? __pfx_vhci_release (drivers/bluetooth/hci_vhci.c:678) [ 97.810404] __fput (fs/file_table.c:470) [ 97.810430] task_work_run (kernel/task_work.c:235) [ 97.810451] ? __pfx_task_work_run (kernel/task_work.c:201) [ 97.810472] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810495] ? do_raw_spin_unlock (./include/asm-generic/qspinlock.h:128 (discriminator 5) kernel/locking/spinlock_debug.c:142 (discriminator 5)) [ 97.810527] do_exit (kernel/exit.c:972) [ 97.810547] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810574] ? __pfx_do_exit (kernel/exit.c:897) [ 97.810594] ? lock_acquire (kernel/locking/lockdep.c:470 (discriminator 6) kernel/locking/lockdep.c:5870 (discriminator 6) kernel/locking/lockdep.c:5825 (discriminator 6)) [ 97.810616] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810639] ? do_raw_spin_lock (kernel/locking/spinlock_debug.c:95 (discriminator 4) kernel/locking/spinlock_debug.c:118 (discriminator 4)) [ 97.810664] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810688] ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1)) [ 97.810721] do_group_exit (kernel/exit.c:1093) [ 97.810745] get_signal (kernel/signal.c:3007 (discriminator 1)) [ 97.810772] ? security_file_permission (./arch/x86/include/asm/jump_label.h:37 security/security.c:2366) [ 97.810803] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810826] ? vfs_read (fs/read_write.c:555) [ 97.810854] ? __pfx_get_signal (kernel/signal.c:2800) [ 97.810880] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810905] ? __pfx_vfs_read (fs/read_write.c:555) [ 97.810932] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.810960] arch_do_signal_or_restart (arch/x86/kernel/signal.c:337 (discriminator 1)) [ 97.810990] ? __pfx_arch_do_signal_or_restart (arch/x86/kernel/signal.c:334) [ 97.811021] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.811055] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.811078] ? ksys_read (fs/read_write.c:707) [ 97.811106] ? __pfx_ksys_read (fs/read_write.c:707) [ 97.811137] exit_to_user_mode_loop (kernel/entry/common.c:66 kernel/entry/common.c:98) [ 97.811169] ? rcu_is_watching (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/context_tracking.h:128 kernel/rcu/tree.c:752) [ 97.811192] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.811215] ? trace_hardirqs_off (./include/trace/events/preemptirq.h:36 (discriminator 33) kernel/trace/trace_preemptirq.c:95 (discriminator 33) kernel/trace/trace_preemptirq.c:90 (discriminator 33)) [ 97.811240] do_syscall_64 (./include/linux/irq-entry-common.h:226 ./include/linux/irq-entry-common.h:256 ./include/linux/entry-common.h:325 arch/x86/entry/syscall_64.c:100) [ 97.811268] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 97.811292] ? exc_page_fault (arch/x86/mm/fault.c:1480 (discriminator 3) arch/x86/mm/fault.c:1527 (discriminator 3)) [ 97.811318] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 97.811338] RIP: 0033:0x445cfe [ 97.811352] Code: Unable to access opcode bytes at 0x445cd4. Code starting with the faulting instruction =========================================== [ 97.811360] RSP: 002b:00007f65c41c6dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 97.811378] RAX: fffffffffffffe00 RBX: 00007f65c41c76c0 RCX: 0000000000445cfe [ 97.811391] RDX: 0000000000000400 RSI: 00007f65c41c6e40 RDI: 0000000000000004 [ 97.811403] RBP: 00007f65c41c7250 R08: 0000000000000000 R09: 0000000000000000 [ 97.811415] R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffe8 [ 97.811428] R13: 0000000000000000 R14: 00007fff780a8c00 R15: 00007f65c41c76c0 [ 97.811453] [ 98.402453] ================================================================== [ 98.403560] BUG: KASAN: use-after-free in __mutex_lock (kernel/locking/mutex.c:199 kernel/locking/mutex.c:694 kernel/locking/mutex.c:776) [ 98.404541] Read of size 8 at addr ffff888113ee40a8 by task khidpd_00050004/1430 [ 98.405361] [ 98.405563] CPU: 1 UID: 0 PID: 1430 Comm: khidpd_00050004 Not tainted 7.0.0-rc1-dirty #14 PREEMPT(lazy) [ 98.405588] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 [ 98.405600] Call Trace: [ 98.405607] [ 98.405614] dump_stack_lvl (lib/dump_stack.c:122) [ 98.405641] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) [ 98.405667] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.405691] ? __virt_addr_valid (arch/x86/mm/physaddr.c:55) [ 98.405724] ? __mutex_lock (kernel/locking/mutex.c:199 kernel/locking/mutex.c:694 kernel/locking/mutex.c:776) [ 98.405748] kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:597) [ 98.405778] ? __mutex_lock (kernel/locking/mutex.c:199 kernel/locking/mutex.c:694 kernel/locking/mutex.c:776) [ 98.405807] __mutex_lock (kernel/locking/mutex.c:199 kernel/locking/mutex.c:694 kernel/locking/mutex.c:776) [ 98.405832] ? do_raw_spin_lock (kernel/locking/spinlock_debug.c:95 (discriminator 4) kernel/locking/spinlock_debug.c:118 (discriminator 4)) [ 98.405859] ? l2cap_unregister_user (./include/linux/list.h:381 (discriminator 2) net/bluetooth/l2cap_core.c:1723 (discriminator 2)) [ 98.405888] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) [ 98.405915] ? __pfx___mutex_lock (kernel/locking/mutex.c:775) [ 98.405939] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.405963] ? lock_acquire (kernel/locking/lockdep.c:470 (discriminator 6) kernel/locking/lockdep.c:5870 (discriminator 6) kernel/locking/lockdep.c:5825 (discriminator 6)) [ 98.405984] ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1)) [ 98.406015] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406038] ? lock_release (kernel/locking/lockdep.c:5536 kernel/locking/lockdep.c:5889 kernel/locking/lockdep.c:5875) [ 98.406061] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406085] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 ./arch/x86/include/asm/irqflags.h:159 ./include/linux/spinlock_api_smp.h:178 kernel/locking/spinlock.c:194) [ 98.406107] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406130] ? __timer_delete_sync (kernel/time/timer.c:1592) [ 98.406158] ? l2cap_unregister_user (./include/linux/list.h:381 (discriminator 2) net/bluetooth/l2cap_core.c:1723 (discriminator 2)) [ 98.406186] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406210] l2cap_unregister_user (./include/linux/list.h:381 (discriminator 2) net/bluetooth/l2cap_core.c:1723 (discriminator 2)) [ 98.406263] hidp_session_thread (./include/linux/instrumented.h:112 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/linux/kref.h:64 net/bluetooth/hidp/core.c:996 net/bluetooth/hidp/core.c:1305) [ 98.406293] ? __pfx_hidp_session_thread (net/bluetooth/hidp/core.c:1264) [ 98.406323] ? kthread (kernel/kthread.c:433) [ 98.406340] ? __pfx_hidp_session_wake_function (net/bluetooth/hidp/core.c:1251) [ 98.406370] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406393] ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1)) [ 98.406424] ? __pfx_hidp_session_wake_function (net/bluetooth/hidp/core.c:1251) [ 98.406453] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406476] ? trace_hardirqs_on (kernel/trace/trace_preemptirq.c:79 (discriminator 1)) [ 98.406499] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406523] ? kthread (kernel/kthread.c:433) [ 98.406539] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406565] ? kthread (kernel/kthread.c:433) [ 98.406581] ? __pfx_hidp_session_thread (net/bluetooth/hidp/core.c:1264) [ 98.406610] kthread (kernel/kthread.c:467) [ 98.406627] ? __pfx_kthread (kernel/kthread.c:412) [ 98.406645] ret_from_fork (arch/x86/kernel/process.c:164) [ 98.406674] ? __pfx_ret_from_fork (arch/x86/kernel/process.c:153) [ 98.406704] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.406728] ? __pfx_kthread (kernel/kthread.c:412) [ 98.406747] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) [ 98.406774] [ 98.406780] [ 98.433693] The buggy address belongs to the physical page: [ 98.434405] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888113ee7c40 pfn:0x113ee4 [ 98.435557] flags: 0x200000000000000(node=0|zone=2) [ 98.436198] raw: 0200000000000000 ffffea0004244308 ffff8881f6f3ebc0 0000000000000000 [ 98.437195] raw: ffff888113ee7c40 0000000000000000 00000000ffffffff 0000000000000000 [ 98.438115] page dumped because: kasan: bad access detected [ 98.438951] [ 98.439211] Memory state around the buggy address: [ 98.439871] ffff888113ee3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 98.440714] ffff888113ee4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 98.441580] >ffff888113ee4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 98.442458] ^ [ 98.443011] ffff888113ee4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 98.443889] ffff888113ee4180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 98.444768] ================================================================== [ 98.445719] Disabling lock debugging due to kernel taint [ 98.448074] l2cap_conn_free: freeing conn ffff88810c22b400 [ 98.450012] CPU: 1 UID: 0 PID: 1430 Comm: khidpd_00050004 Tainted: G B 7.0.0-rc1-dirty #14 PREEMPT(lazy) [ 98.450040] Tainted: [B]=BAD_PAGE [ 98.450047] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 [ 98.450059] Call Trace: [ 98.450065] [ 98.450071] dump_stack_lvl (lib/dump_stack.c:122) [ 98.450099] l2cap_conn_free (net/bluetooth/l2cap_core.c:1808) [ 98.450125] l2cap_conn_put (net/bluetooth/l2cap_core.c:1822) [ 98.450154] session_free (net/bluetooth/hidp/core.c:990) [ 98.450181] hidp_session_thread (net/bluetooth/hidp/core.c:1307) [ 98.450213] ? __pfx_hidp_session_thread (net/bluetooth/hidp/core.c:1264) [ 98.450271] ? kthread (kernel/kthread.c:433) [ 98.450293] ? __pfx_hidp_session_wake_function (net/bluetooth/hidp/core.c:1251) [ 98.450339] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.450368] ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1)) [ 98.450406] ? __pfx_hidp_session_wake_function (net/bluetooth/hidp/core.c:1251) [ 98.450442] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.450471] ? trace_hardirqs_on (kernel/trace/trace_preemptirq.c:79 (discriminator 1)) [ 98.450499] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.450528] ? kthread (kernel/kthread.c:433) [ 98.450547] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.450578] ? kthread (kernel/kthread.c:433) [ 98.450598] ? __pfx_hidp_session_thread (net/bluetooth/hidp/core.c:1264) [ 98.450637] kthread (kernel/kthread.c:467) [ 98.450657] ? __pfx_kthread (kernel/kthread.c:412) [ 98.450680] ret_from_fork (arch/x86/kernel/process.c:164) [ 98.450715] ? __pfx_ret_from_fork (arch/x86/kernel/process.c:153) [ 98.450752] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 98.450782] ? __pfx_kthread (kernel/kthread.c:412) [ 98.450804] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) [ 98.450836] Fixes: b4f34d8d9d26 ("Bluetooth: hidp: add new session-management helpers") Reported-by: soufiane el hachmi Tested-by: soufiane el hachmi Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hidp/core.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c index 6fe815241b01..7bcf8c5ceaee 100644 --- a/net/bluetooth/hidp/core.c +++ b/net/bluetooth/hidp/core.c @@ -986,7 +986,8 @@ static void session_free(struct kref *ref) skb_queue_purge(&session->intr_transmit); fput(session->intr_sock->file); fput(session->ctrl_sock->file); - l2cap_conn_put(session->conn); + if (session->conn) + l2cap_conn_put(session->conn); kfree(session); } @@ -1164,6 +1165,15 @@ static void hidp_session_remove(struct l2cap_conn *conn, down_write(&hidp_session_sem); + /* Drop L2CAP reference immediately to indicate that + * l2cap_unregister_user() shall not be called as it is already + * considered removed. + */ + if (session->conn) { + l2cap_conn_put(session->conn); + session->conn = NULL; + } + hidp_session_terminate(session); cancel_work_sync(&session->dev_init); @@ -1301,7 +1311,9 @@ static int hidp_session_thread(void *arg) * Instead, this call has the same semantics as if user-space tried to * delete the session. */ - l2cap_unregister_user(session->conn, &session->user); + if (session->conn) + l2cap_unregister_user(session->conn, &session->user); + hidp_session_put(session); module_put_and_kthread_exit(0); -- cgit v1.2.3 From 752a6c9596dd25efd6978a73ff21f3b592668f4a Mon Sep 17 00:00:00 2001 From: Shaurya Rane Date: Thu, 6 Nov 2025 23:50:16 +0530 Subject: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to conn->users. However, l2cap_register_user() and l2cap_unregister_user() don't use conn->lock, creating a race condition where these functions can access conn->users and conn->hchan concurrently with l2cap_conn_del(). This can lead to use-after-free and list corruption bugs, as reported by syzbot. Fix this by changing l2cap_register_user() and l2cap_unregister_user() to use conn->lock instead of hci_dev_lock(), ensuring consistent locking for the l2cap_conn structure. Reported-by: syzbot+14b6d57fb728e27ce23c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=14b6d57fb728e27ce23c Fixes: ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del") Signed-off-by: Shaurya Rane Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 0f400051f093..780136e18aae 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1678,17 +1678,15 @@ static void l2cap_info_timeout(struct work_struct *work) int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user) { - struct hci_dev *hdev = conn->hcon->hdev; int ret; /* We need to check whether l2cap_conn is registered. If it is not, we - * must not register the l2cap_user. l2cap_conn_del() is unregisters - * l2cap_conn objects, but doesn't provide its own locking. Instead, it - * relies on the parent hci_conn object to be locked. This itself relies - * on the hci_dev object to be locked. So we must lock the hci device - * here, too. */ + * must not register the l2cap_user. l2cap_conn_del() unregisters + * l2cap_conn objects under conn->lock, and we use the same lock here + * to protect access to conn->users and conn->hchan. + */ - hci_dev_lock(hdev); + mutex_lock(&conn->lock); if (!list_empty(&user->list)) { ret = -EINVAL; @@ -1709,16 +1707,14 @@ int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user) ret = 0; out_unlock: - hci_dev_unlock(hdev); + mutex_unlock(&conn->lock); return ret; } EXPORT_SYMBOL(l2cap_register_user); void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user) { - struct hci_dev *hdev = conn->hcon->hdev; - - hci_dev_lock(hdev); + mutex_lock(&conn->lock); if (list_empty(&user->list)) goto out_unlock; @@ -1727,7 +1723,7 @@ void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user) user->remove(conn, user); out_unlock: - hci_dev_unlock(hdev); + mutex_unlock(&conn->lock); } EXPORT_SYMBOL(l2cap_unregister_user); -- cgit v1.2.3 From 5b3e2052334f2ff6d5200e952f4aa66994d09899 Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Tue, 3 Mar 2026 13:29:53 -0500 Subject: Bluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ Currently the code attempts to accept requests regardless of the command identifier which may cause multiple requests to be marked as pending (FLAG_DEFER_SETUP) which can cause more than L2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer causing an overflow. The spec is quite clear that the same identifier shall not be used on subsequent requests: 'Within each signaling channel a different Identifier shall be used for each successive request or indication.' https://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d So this attempts to check if there are any channels pending with the same identifier and rejects if any are found. Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Reported-by: Yiming Qian Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 780136e18aae..9d5b8d4d375a 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5055,7 +5055,7 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, u16 mtu, mps; __le16 psm; u8 result, rsp_len = 0; - int i, num_scid; + int i, num_scid = 0; bool defer = false; if (!enable_ecred) @@ -5068,6 +5068,14 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, goto response; } + /* Check if there are no pending channels with the same ident */ + __l2cap_chan_list_id(conn, cmd->ident, l2cap_ecred_list_defer, + &num_scid); + if (num_scid) { + result = L2CAP_CR_LE_INVALID_PARAMS; + goto response; + } + cmd_len -= sizeof(*req); num_scid = cmd_len / sizeof(u16); -- cgit v1.2.3 From 15145675690cab2de1056e7ed68e59cbd0452529 Mon Sep 17 00:00:00 2001 From: Lukas Johannes Möller Date: Tue, 10 Mar 2026 21:59:46 +0000 Subject: Bluetooth: L2CAP: Fix type confusion in l2cap_ecred_reconf_rsp() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit l2cap_ecred_reconf_rsp() casts the incoming data to struct l2cap_ecred_conn_rsp (the ECRED *connection* response, 8 bytes with result at offset 6) instead of struct l2cap_ecred_reconf_rsp (2 bytes with result at offset 0). This causes two problems: - The sizeof(*rsp) length check requires 8 bytes instead of the correct 2, so valid L2CAP_ECRED_RECONF_RSP packets are rejected with -EPROTO. - rsp->result reads from offset 6 instead of offset 0, returning wrong data when the packet is large enough to pass the check. Fix by using the correct type. Also pass the already byte-swapped result variable to BT_DBG instead of the raw __le16 field. Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Cc: stable@vger.kernel.org Signed-off-by: Lukas Johannes Möller Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 9d5b8d4d375a..08a12515bfed 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5428,7 +5428,7 @@ static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn, u8 *data) { struct l2cap_chan *chan, *tmp; - struct l2cap_ecred_conn_rsp *rsp = (void *) data; + struct l2cap_ecred_reconf_rsp *rsp = (void *)data; u16 result; if (cmd_len < sizeof(*rsp)) @@ -5436,7 +5436,7 @@ static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn, result = __le16_to_cpu(rsp->result); - BT_DBG("result 0x%4.4x", rsp->result); + BT_DBG("result 0x%4.4x", result); if (!result) return 0; -- cgit v1.2.3 From dd815e6e3918dc75a49aaabac36e4f024d675101 Mon Sep 17 00:00:00 2001 From: Lukas Johannes Möller Date: Tue, 10 Mar 2026 21:59:47 +0000 Subject: Bluetooth: L2CAP: Validate L2CAP_INFO_RSP payload length before access MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit l2cap_information_rsp() checks that cmd_len covers the fixed l2cap_info_rsp header (type + result, 4 bytes) but then reads rsp->data without verifying that the payload is present: - L2CAP_IT_FEAT_MASK calls get_unaligned_le32(rsp->data), which reads 4 bytes past the header (needs cmd_len >= 8). - L2CAP_IT_FIXED_CHAN reads rsp->data[0], 1 byte past the header (needs cmd_len >= 5). A truncated L2CAP_INFO_RSP with result == L2CAP_IR_SUCCESS triggers an out-of-bounds read of adjacent skb data. Guard each data access with the required payload length check. If the payload is too short, skip the read and let the state machine complete with safe defaults (feat_mask and remote_fixed_chan remain zero from kzalloc), so the info timer cleanup and l2cap_conn_start() still run and the connection is not stalled. Fixes: 4e8402a3f884 ("[Bluetooth] Retrieve L2CAP features mask on connection setup") Cc: stable@vger.kernel.org Signed-off-by: Lukas Johannes Möller Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 08a12515bfed..5deb6c4f1e41 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4612,7 +4612,8 @@ static inline int l2cap_information_rsp(struct l2cap_conn *conn, switch (type) { case L2CAP_IT_FEAT_MASK: - conn->feat_mask = get_unaligned_le32(rsp->data); + if (cmd_len >= sizeof(*rsp) + sizeof(u32)) + conn->feat_mask = get_unaligned_le32(rsp->data); if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) { struct l2cap_info_req req; @@ -4631,7 +4632,8 @@ static inline int l2cap_information_rsp(struct l2cap_conn *conn, break; case L2CAP_IT_FIXED_CHAN: - conn->remote_fixed_chan = rsp->data[0]; + if (cmd_len >= sizeof(*rsp) + sizeof(rsp->data[0])) + conn->remote_fixed_chan = rsp->data[0]; conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE; conn->info_ident = 0; -- cgit v1.2.3 From e5b31d988a41549037b8d8721a3c3cae893d8670 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 11 Mar 2026 05:40:40 +0000 Subject: af_unix: Give up GC if MSG_PEEK intervened. Igor Ushakov reported that GC purged the receive queue of an alive socket due to a race with MSG_PEEK with a nice repro. This is the exact same issue previously fixed by commit cbcf01128d0a ("af_unix: fix garbage collect vs MSG_PEEK"). After GC was replaced with the current algorithm, the cited commit removed the locking dance in unix_peek_fds() and reintroduced the same issue. The problem is that MSG_PEEK bumps a file refcount without interacting with GC. Consider an SCC containing sk-A and sk-B, where sk-A is close()d but can be recv()ed via sk-B. The bad thing happens if sk-A is recv()ed with MSG_PEEK from sk-B and sk-B is close()d while GC is checking unix_vertex_dead() for sk-A and sk-B. GC thread User thread --------- ----------- unix_vertex_dead(sk-A) -> true <------. \ `------ recv(sk-B, MSG_PEEK) invalidate !! -> sk-A's file refcount : 1 -> 2 close(sk-B) -> sk-B's file refcount : 2 -> 1 unix_vertex_dead(sk-B) -> true Initially, sk-A's file refcount is 1 by the inflight fd in sk-B recvq. GC thinks sk-A is dead because the file refcount is the same as the number of its inflight fds. However, sk-A's file refcount is bumped silently by MSG_PEEK, which invalidates the previous evaluation. At this moment, sk-B's file refcount is 2; one by the open fd, and one by the inflight fd in sk-A. The subsequent close() releases one refcount by the former. Finally, GC incorrectly concludes that both sk-A and sk-B are dead. One option is to restore the locking dance in unix_peek_fds(), but we can resolve this more elegantly thanks to the new algorithm. The point is that the issue does not occur without the subsequent close() and we actually do not need to synchronise MSG_PEEK with the dead SCC detection. When the issue occurs, close() and GC touch the same file refcount. If GC sees the refcount being decremented by close(), it can just give up garbage-collecting the SCC. Therefore, we only need to signal the race during MSG_PEEK with a proper memory barrier to make it visible to the GC. Let's use seqcount_t to notify GC when MSG_PEEK occurs and let it defer the SCC to the next run. This way no locking is needed on the MSG_PEEK side, and we can avoid imposing a penalty on every MSG_PEEK unnecessarily. Note that we can retry within unix_scc_dead() if MSG_PEEK is detected, but we do not do so to avoid hung task splat from abusive MSG_PEEK calls. Fixes: 118f457da9ed ("af_unix: Remove lock dance in unix_peek_fds().") Reported-by: Igor Ushakov Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260311054043.1231316-1-kuniyu@google.com Signed-off-by: Jakub Kicinski --- net/unix/af_unix.c | 2 ++ net/unix/af_unix.h | 1 + net/unix/garbage.c | 79 +++++++++++++++++++++++++++++++++++------------------- 3 files changed, 54 insertions(+), 28 deletions(-) (limited to 'net') diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 7eaa5b187fef..b23c33df8b46 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1958,6 +1958,8 @@ static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) static void unix_peek_fds(struct scm_cookie *scm, struct sk_buff *skb) { scm->fp = scm_fp_dup(UNIXCB(skb).fp); + + unix_peek_fpl(scm->fp); } static void unix_destruct_scm(struct sk_buff *skb) diff --git a/net/unix/af_unix.h b/net/unix/af_unix.h index c4f1b2da363d..8119dbeef3a3 100644 --- a/net/unix/af_unix.h +++ b/net/unix/af_unix.h @@ -29,6 +29,7 @@ void unix_del_edges(struct scm_fp_list *fpl); void unix_update_edges(struct unix_sock *receiver); int unix_prepare_fpl(struct scm_fp_list *fpl); void unix_destroy_fpl(struct scm_fp_list *fpl); +void unix_peek_fpl(struct scm_fp_list *fpl); void unix_schedule_gc(struct user_struct *user); /* SOCK_DIAG */ diff --git a/net/unix/garbage.c b/net/unix/garbage.c index 816e8fa2b062..a7967a345827 100644 --- a/net/unix/garbage.c +++ b/net/unix/garbage.c @@ -318,6 +318,25 @@ void unix_destroy_fpl(struct scm_fp_list *fpl) unix_free_vertices(fpl); } +static bool gc_in_progress; +static seqcount_t unix_peek_seq = SEQCNT_ZERO(unix_peek_seq); + +void unix_peek_fpl(struct scm_fp_list *fpl) +{ + static DEFINE_SPINLOCK(unix_peek_lock); + + if (!fpl || !fpl->count_unix) + return; + + if (!READ_ONCE(gc_in_progress)) + return; + + /* Invalidate the final refcnt check in unix_vertex_dead(). */ + spin_lock(&unix_peek_lock); + raw_write_seqcount_barrier(&unix_peek_seq); + spin_unlock(&unix_peek_lock); +} + static bool unix_vertex_dead(struct unix_vertex *vertex) { struct unix_edge *edge; @@ -351,6 +370,36 @@ static bool unix_vertex_dead(struct unix_vertex *vertex) return true; } +static LIST_HEAD(unix_visited_vertices); +static unsigned long unix_vertex_grouped_index = UNIX_VERTEX_INDEX_MARK2; + +static bool unix_scc_dead(struct list_head *scc, bool fast) +{ + struct unix_vertex *vertex; + bool scc_dead = true; + unsigned int seq; + + seq = read_seqcount_begin(&unix_peek_seq); + + list_for_each_entry_reverse(vertex, scc, scc_entry) { + /* Don't restart DFS from this vertex. */ + list_move_tail(&vertex->entry, &unix_visited_vertices); + + /* Mark vertex as off-stack for __unix_walk_scc(). */ + if (!fast) + vertex->index = unix_vertex_grouped_index; + + if (scc_dead) + scc_dead = unix_vertex_dead(vertex); + } + + /* If MSG_PEEK intervened, defer this SCC to the next round. */ + if (read_seqcount_retry(&unix_peek_seq, seq)) + return false; + + return scc_dead; +} + static void unix_collect_skb(struct list_head *scc, struct sk_buff_head *hitlist) { struct unix_vertex *vertex; @@ -404,9 +453,6 @@ static bool unix_scc_cyclic(struct list_head *scc) return false; } -static LIST_HEAD(unix_visited_vertices); -static unsigned long unix_vertex_grouped_index = UNIX_VERTEX_INDEX_MARK2; - static unsigned long __unix_walk_scc(struct unix_vertex *vertex, unsigned long *last_index, struct sk_buff_head *hitlist) @@ -474,9 +520,7 @@ prev_vertex: } if (vertex->index == vertex->scc_index) { - struct unix_vertex *v; struct list_head scc; - bool scc_dead = true; /* SCC finalised. * @@ -485,18 +529,7 @@ prev_vertex: */ __list_cut_position(&scc, &vertex_stack, &vertex->scc_entry); - list_for_each_entry_reverse(v, &scc, scc_entry) { - /* Don't restart DFS from this vertex in unix_walk_scc(). */ - list_move_tail(&v->entry, &unix_visited_vertices); - - /* Mark vertex as off-stack. */ - v->index = unix_vertex_grouped_index; - - if (scc_dead) - scc_dead = unix_vertex_dead(v); - } - - if (scc_dead) { + if (unix_scc_dead(&scc, false)) { unix_collect_skb(&scc, hitlist); } else { if (unix_vertex_max_scc_index < vertex->scc_index) @@ -550,19 +583,11 @@ static void unix_walk_scc_fast(struct sk_buff_head *hitlist) while (!list_empty(&unix_unvisited_vertices)) { struct unix_vertex *vertex; struct list_head scc; - bool scc_dead = true; vertex = list_first_entry(&unix_unvisited_vertices, typeof(*vertex), entry); list_add(&scc, &vertex->scc_entry); - list_for_each_entry_reverse(vertex, &scc, scc_entry) { - list_move_tail(&vertex->entry, &unix_visited_vertices); - - if (scc_dead) - scc_dead = unix_vertex_dead(vertex); - } - - if (scc_dead) { + if (unix_scc_dead(&scc, true)) { cyclic_sccs--; unix_collect_skb(&scc, hitlist); } @@ -577,8 +602,6 @@ static void unix_walk_scc_fast(struct sk_buff_head *hitlist) cyclic_sccs ? UNIX_GRAPH_CYCLIC : UNIX_GRAPH_NOT_CYCLIC); } -static bool gc_in_progress; - static void unix_gc(struct work_struct *work) { struct sk_buff_head hitlist; -- cgit v1.2.3 From 3715a00855316066cdda69d43648336367422127 Mon Sep 17 00:00:00 2001 From: Hyunwoo Kim Date: Wed, 11 Mar 2026 03:18:09 +0900 Subject: bridge: cfm: Fix race condition in peer_mep deletion When a peer MEP is being deleted, cancel_delayed_work_sync() is called on ccm_rx_dwork before freeing. However, br_cfm_frame_rx() runs in softirq context under rcu_read_lock (without RTNL) and can re-schedule ccm_rx_dwork via ccm_rx_timer_start() between cancel_delayed_work_sync() returning and kfree_rcu() being called. The following is a simple race scenario: cpu0 cpu1 mep_delete_implementation() cancel_delayed_work_sync(ccm_rx_dwork); br_cfm_frame_rx() // peer_mep still in hlist if (peer_mep->ccm_defect) ccm_rx_timer_start() queue_delayed_work(ccm_rx_dwork) hlist_del_rcu(&peer_mep->head); kfree_rcu(peer_mep, rcu); ccm_rx_work_expired() // on freed peer_mep To prevent this, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync() in both peer MEP deletion paths, so that subsequent queue_delayed_work() calls from br_cfm_frame_rx() are silently rejected. The cc_peer_disable() helper retains cancel_delayed_work_sync() because it is also used for the CC enable/disable toggle path where the work must remain re-schedulable. Fixes: dc32cbb3dbd7 ("bridge: cfm: Kernel space implementation of CFM. CCM frame RX added.") Signed-off-by: Hyunwoo Kim Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/abBgYT5K_FI9rD1a@v4bel Signed-off-by: Jakub Kicinski --- net/bridge/br_cfm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/bridge/br_cfm.c b/net/bridge/br_cfm.c index 2c70fe47de38..118c7ea48c35 100644 --- a/net/bridge/br_cfm.c +++ b/net/bridge/br_cfm.c @@ -576,7 +576,7 @@ static void mep_delete_implementation(struct net_bridge *br, /* Empty and free peer MEP list */ hlist_for_each_entry_safe(peer_mep, n_store, &mep->peer_mep_list, head) { - cancel_delayed_work_sync(&peer_mep->ccm_rx_dwork); + disable_delayed_work_sync(&peer_mep->ccm_rx_dwork); hlist_del_rcu(&peer_mep->head); kfree_rcu(peer_mep, rcu); } @@ -732,7 +732,7 @@ int br_cfm_cc_peer_mep_remove(struct net_bridge *br, const u32 instance, return -ENOENT; } - cc_peer_disable(peer_mep); + disable_delayed_work_sync(&peer_mep->ccm_rx_dwork); hlist_del_rcu(&peer_mep->head); kfree_rcu(peer_mep, rcu); -- cgit v1.2.3 From e1f0a18c9564cdb16523c802e2c6fe5874e3d944 Mon Sep 17 00:00:00 2001 From: Jiayuan Chen Date: Wed, 11 Mar 2026 15:06:02 +0800 Subject: net/rose: fix NULL pointer dereference in rose_transmit_link on reconnect syzkaller reported a bug [1], and the reproducer is available at [2]. ROSE sockets use four sk->sk_state values: TCP_CLOSE, TCP_LISTEN, TCP_SYN_SENT, and TCP_ESTABLISHED. rose_connect() already rejects calls for TCP_ESTABLISHED (-EISCONN) and TCP_CLOSE with SS_CONNECTING (-ECONNREFUSED), but lacks a check for TCP_SYN_SENT. When rose_connect() is called a second time while the first connection attempt is still in progress (TCP_SYN_SENT), it overwrites rose->neighbour via rose_get_neigh(). If that returns NULL, the socket is left with rose->state == ROSE_STATE_1 but rose->neighbour == NULL. When the socket is subsequently closed, rose_release() sees ROSE_STATE_1 and calls rose_write_internal() -> rose_transmit_link(skb, NULL), causing a NULL pointer dereference. Per connect(2), a second connect() while a connection is already in progress should return -EALREADY. Add this missing check for TCP_SYN_SENT to complete the state validation in rose_connect(). [1] https://syzkaller.appspot.com/bug?extid=d00f90e0af54102fb271 [2] https://gist.github.com/mrpre/9e6779e0d13e2c66779b1653fef80516 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+d00f90e0af54102fb271@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69694d6f.050a0220.58bed.0027.GAE@google.com/T/ Suggested-by: Eric Dumazet Signed-off-by: Jiayuan Chen Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260311070611.76913-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski --- net/rose/af_rose.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net') diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c index 841d62481048..ba56213e0a2a 100644 --- a/net/rose/af_rose.c +++ b/net/rose/af_rose.c @@ -811,6 +811,11 @@ static int rose_connect(struct socket *sock, struct sockaddr_unsized *uaddr, int goto out_release; } + if (sk->sk_state == TCP_SYN_SENT) { + err = -EALREADY; + goto out_release; + } + sk->sk_state = TCP_CLOSE; sock->state = SS_UNCONNECTED; -- cgit v1.2.3 From 99600f79b28c83c68bae199a3d8e95049a758308 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Wed, 11 Mar 2026 23:35:09 +0100 Subject: mpls: add missing unregister_netdevice_notifier to mpls_init If mpls_init() fails after registering mpls_dev_notifier, it never gets removed. Add the missing unregister_netdevice_notifier() call to the error handling path. Fixes: 5be2062e3080 ("mpls: Handle error of rtnl_register_module().") Signed-off-by: Sabrina Dubroca Link: https://patch.msgid.link/7c55363c4f743d19e2306204a134407c90a69bbb.1773228081.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski --- net/mpls/af_mpls.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index ef9e749d5e08..d5417688f69e 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -2854,6 +2854,7 @@ out_unregister_rtnl_af: rtnl_af_unregister(&mpls_af_ops); out_unregister_dev_type: dev_remove_pack(&mpls_packet_type); + unregister_netdevice_notifier(&mpls_dev_notifier); out_unregister_pernet: unregister_pernet_subsys(&mpls_net_ops); goto out; -- cgit v1.2.3 From 7d73872d949c488a1d7c308031d6a9d89b5e0a8b Mon Sep 17 00:00:00 2001 From: Deepanshu Kartikey Date: Fri, 13 Mar 2026 14:54:17 +0530 Subject: wifi: mac80211: check tdls flag in ieee80211_tdls_oper When NL80211_TDLS_ENABLE_LINK is called, the code only checks if the station exists but not whether it is actually a TDLS station. This allows the operation to proceed for non-TDLS stations, causing unintended side effects like modifying channel context and HT protection before failing. Add a check for sta->sta.tdls early in the ENABLE_LINK case, before any side effects occur, to ensure the operation is only allowed for actual TDLS peers. Reported-by: syzbot+56b6a844a4ea74487b7b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=56b6a844a4ea74487b7b Tested-by: syzbot+56b6a844a4ea74487b7b@syzkaller.appspotmail.com Suggested-by: Johannes Berg Signed-off-by: Deepanshu Kartikey Link: https://patch.msgid.link/20260313092417.520807-1-kartikey406@gmail.com Signed-off-by: Johannes Berg --- net/mac80211/tdls.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c index dbbfe2d6842f..1dca2fae05a5 100644 --- a/net/mac80211/tdls.c +++ b/net/mac80211/tdls.c @@ -1449,7 +1449,7 @@ int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev, } sta = sta_info_get(sdata, peer); - if (!sta) + if (!sta || !sta->sta.tdls) return -ENOLINK; iee80211_tdls_recalc_chanctx(sdata, sta); -- cgit v1.2.3 From 5cb81eeda909dbb2def209dd10636b51549a3f8a Mon Sep 17 00:00:00 2001 From: Hyunwoo Kim Date: Sun, 8 Mar 2026 02:21:37 +0900 Subject: netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct() ctnetlink_dump_exp_ct() stores a conntrack pointer in cb->data for the netlink dump callback ctnetlink_exp_ct_dump_table(), but drops the conntrack reference immediately after netlink_dump_start(). When the dump spans multiple rounds, the second recvmsg() triggers the dump callback which dereferences the now-freed conntrack via nfct_help(ct), leading to a use-after-free on ct->ext. The bug is that the netlink_dump_control has no .start or .done callbacks to manage the conntrack reference across dump rounds. Other dump functions in the same file (e.g. ctnetlink_get_conntrack) properly use .start/.done callbacks for this purpose. Fix this by adding .start and .done callbacks that hold and release the conntrack reference for the duration of the dump, and move the nfct_help() call after the cb->args[0] early-return check in the dump callback to avoid dereferencing ct->ext unnecessarily. BUG: KASAN: slab-use-after-free in ctnetlink_exp_ct_dump_table+0x4f/0x2e0 Read of size 8 at addr ffff88810597ebf0 by task ctnetlink_poc/133 CPU: 1 UID: 0 PID: 133 Comm: ctnetlink_poc Not tainted 7.0.0-rc2+ #3 PREEMPTLAZY Call Trace: ctnetlink_exp_ct_dump_table+0x4f/0x2e0 netlink_dump+0x333/0x880 netlink_recvmsg+0x3e2/0x4b0 ? aa_sk_perm+0x184/0x450 sock_recvmsg+0xde/0xf0 Allocated by task 133: kmem_cache_alloc_noprof+0x134/0x440 __nf_conntrack_alloc+0xa8/0x2b0 ctnetlink_create_conntrack+0xa1/0x900 ctnetlink_new_conntrack+0x3cf/0x7d0 nfnetlink_rcv_msg+0x48e/0x510 netlink_rcv_skb+0xc9/0x1f0 nfnetlink_rcv+0xdb/0x220 netlink_unicast+0x3ec/0x590 netlink_sendmsg+0x397/0x690 __sys_sendmsg+0xf4/0x180 Freed by task 0: slab_free_after_rcu_debug+0xad/0x1e0 rcu_core+0x5c3/0x9c0 Fixes: e844a928431f ("netfilter: ctnetlink: allow to dump expectation per master conntrack") Signed-off-by: Hyunwoo Kim Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_netlink.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index c9d725fc2d71..65aa44a12d01 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -3212,7 +3212,7 @@ ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb) { struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh); struct nf_conn *ct = cb->data; - struct nf_conn_help *help = nfct_help(ct); + struct nf_conn_help *help; u_int8_t l3proto = nfmsg->nfgen_family; unsigned long last_id = cb->args[1]; struct nf_conntrack_expect *exp; @@ -3220,6 +3220,10 @@ ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb) if (cb->args[0]) return 0; + help = nfct_help(ct); + if (!help) + return 0; + rcu_read_lock(); restart: @@ -3249,6 +3253,24 @@ out: return skb->len; } +static int ctnetlink_dump_exp_ct_start(struct netlink_callback *cb) +{ + struct nf_conn *ct = cb->data; + + if (!refcount_inc_not_zero(&ct->ct_general.use)) + return -ENOENT; + return 0; +} + +static int ctnetlink_dump_exp_ct_done(struct netlink_callback *cb) +{ + struct nf_conn *ct = cb->data; + + if (ct) + nf_ct_put(ct); + return 0; +} + static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl, struct sk_buff *skb, const struct nlmsghdr *nlh, @@ -3264,6 +3286,8 @@ static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl, struct nf_conntrack_zone zone; struct netlink_dump_control c = { .dump = ctnetlink_exp_ct_dump_table, + .start = ctnetlink_dump_exp_ct_start, + .done = ctnetlink_dump_exp_ct_done, }; err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, -- cgit v1.2.3 From f900e1d77ee0ef87bfb5ab3fe60f0b3d8ad5ba05 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 10 Mar 2026 00:28:29 +0100 Subject: netfilter: conntrack: add missing netlink policy validations Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink. These attributes are used by the kernel without any validation. Extend the netlink policies accordingly. Quoting the reporter: nlattr_to_sctp() assigns the user-supplied CTA_PROTOINFO_SCTP_STATE value directly to ct->proto.sctp.state without checking that it is within the valid range. [..] and: ... with exp->dir = 100, the access at ct->master->tuplehash[100] reads 5600 bytes past the start of a 320-byte nf_conn object, causing a slab-out-of-bounds read confirmed by UBSAN. Fixes: 076a0ca02644 ("netfilter: ctnetlink: add NAT support for expectations") Fixes: a258860e01b8 ("netfilter: ctnetlink: add full support for SCTP to ctnetlink") Reported-by: Hyunwoo Kim Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_netlink.c | 2 +- net/netfilter/nf_conntrack_proto_sctp.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 65aa44a12d01..c156574e1273 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -3489,7 +3489,7 @@ ctnetlink_change_expect(struct nf_conntrack_expect *x, #if IS_ENABLED(CONFIG_NF_NAT) static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = { - [CTA_EXPECT_NAT_DIR] = { .type = NLA_U32 }, + [CTA_EXPECT_NAT_DIR] = NLA_POLICY_MAX(NLA_BE32, IP_CT_DIR_REPLY), [CTA_EXPECT_NAT_TUPLE] = { .type = NLA_NESTED }, }; #endif diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 7c6f7c9f7332..645d2c43ebf7 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -582,7 +582,8 @@ nla_put_failure: } static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = { - [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 }, + [CTA_PROTOINFO_SCTP_STATE] = NLA_POLICY_MAX(NLA_U8, + SCTP_CONNTRACK_HEARTBEAT_SENT), [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 }, [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 }, }; -- cgit v1.2.3 From fbce58e719a17aa215c724473fd5baaa4a8dc57c Mon Sep 17 00:00:00 2001 From: Lukas Johannes Möller Date: Tue, 10 Mar 2026 21:49:01 +0000 Subject: netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sip_help_tcp() parses the SIP Content-Length header with simple_strtoul(), which returns unsigned long, but stores the result in unsigned int clen. On 64-bit systems, values exceeding UINT_MAX are silently truncated before computing the SIP message boundary. For example, Content-Length 4294967328 (2^32 + 32) is truncated to 32, causing the parser to miscalculate where the current message ends. The loop then treats trailing data in the TCP segment as a second SIP message and processes it through the SDP parser. Fix this by changing clen to unsigned long to match the return type of simple_strtoul(), and reject Content-Length values that exceed the remaining TCP payload length. Fixes: f5b321bd37fb ("netfilter: nf_conntrack_sip: add TCP support") Signed-off-by: Lukas Johannes Möller Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_sip.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index ca748f8dbff1..4ab5ef71d96d 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -1534,11 +1534,12 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, { struct tcphdr *th, _tcph; unsigned int dataoff, datalen; - unsigned int matchoff, matchlen, clen; + unsigned int matchoff, matchlen; unsigned int msglen, origlen; const char *dptr, *end; s16 diff, tdiff = 0; int ret = NF_ACCEPT; + unsigned long clen; bool term; if (ctinfo != IP_CT_ESTABLISHED && @@ -1573,6 +1574,9 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, if (dptr + matchoff == end) break; + if (clen > datalen) + break; + term = false; for (; end + strlen("\r\n\r\n") <= dptr + datalen; end++) { if (end[0] == '\r' && end[1] == '\n' && -- cgit v1.2.3 From 598adea720b97572c7028635cb1c59b3684e128c Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 11 Mar 2026 16:24:02 +0100 Subject: netfilter: revert nft_set_rbtree: validate open interval overlap This reverts commit 648946966a08 ("netfilter: nft_set_rbtree: validate open interval overlap"). There have been reports of nft failing to laod valid rulesets after this patch was merged into -stable. I can reproduce several such problem with recent nft versions, including nft 1.1.6 which is widely shipped by distributions. We currently have little choice here. This commit can be resurrected at some point once the nftables fix that triggers the false overlap positive has appeared in common distros (see e83e32c8d1cd ("mnl: restore create element command with large batches" in nftables.git). Fixes: 648946966a08 ("netfilter: nft_set_rbtree: validate open interval overlap") Acked-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- include/net/netfilter/nf_tables.h | 4 --- net/netfilter/nf_tables_api.c | 21 +++--------- net/netfilter/nft_set_rbtree.c | 71 ++++++--------------------------------- 3 files changed, 14 insertions(+), 82 deletions(-) (limited to 'net') diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index e2d2bfc1f989..6299af4ef423 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -277,8 +277,6 @@ struct nft_userdata { unsigned char data[]; }; -#define NFT_SET_ELEM_INTERNAL_LAST 0x1 - /* placeholder structure for opaque set element backend representation. */ struct nft_elem_priv { }; @@ -288,7 +286,6 @@ struct nft_elem_priv { }; * @key: element key * @key_end: closing element key * @data: element data - * @flags: flags * @priv: element private data and extensions */ struct nft_set_elem { @@ -304,7 +301,6 @@ struct nft_set_elem { u32 buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)]; struct nft_data val; } data; - u32 flags; struct nft_elem_priv *priv; }; diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index dacec5f8a11c..4ccdd33cf133 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7156,8 +7156,7 @@ static u32 nft_set_maxsize(const struct nft_set *set) } static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, - const struct nlattr *attr, u32 nlmsg_flags, - bool last) + const struct nlattr *attr, u32 nlmsg_flags) { struct nft_expr *expr_array[NFT_SET_EXPR_MAX] = {}; struct nlattr *nla[NFTA_SET_ELEM_MAX + 1]; @@ -7444,11 +7443,6 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, if (flags) *nft_set_ext_flags(ext) = flags; - if (last) - elem.flags = NFT_SET_ELEM_INTERNAL_LAST; - else - elem.flags = 0; - if (obj) *nft_set_ext_obj(ext) = obj; @@ -7613,8 +7607,7 @@ static int nf_tables_newsetelem(struct sk_buff *skb, nft_ctx_init(&ctx, net, skb, info->nlh, family, table, NULL, nla); nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) { - err = nft_add_set_elem(&ctx, set, attr, info->nlh->nlmsg_flags, - nla_is_last(attr, rem)); + err = nft_add_set_elem(&ctx, set, attr, info->nlh->nlmsg_flags); if (err < 0) { NL_SET_BAD_ATTR(extack, attr); return err; @@ -7738,7 +7731,7 @@ static void nft_trans_elems_destroy_abort(const struct nft_ctx *ctx, } static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set, - const struct nlattr *attr, bool last) + const struct nlattr *attr) { struct nlattr *nla[NFTA_SET_ELEM_MAX + 1]; struct nft_set_ext_tmpl tmpl; @@ -7806,11 +7799,6 @@ static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set, if (flags) *nft_set_ext_flags(ext) = flags; - if (last) - elem.flags = NFT_SET_ELEM_INTERNAL_LAST; - else - elem.flags = 0; - trans = nft_trans_elem_alloc(ctx, NFT_MSG_DELSETELEM, set); if (trans == NULL) goto fail_trans; @@ -7961,8 +7949,7 @@ static int nf_tables_delsetelem(struct sk_buff *skb, return nft_set_flush(&ctx, set, genmask); nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) { - err = nft_del_setelem(&ctx, set, attr, - nla_is_last(attr, rem)); + err = nft_del_setelem(&ctx, set, attr); if (err == -ENOENT && NFNL_MSG_TYPE(info->nlh->nlmsg_type) == NFT_MSG_DESTROYSETELEM) continue; diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c index ee3d4f5b9ff7..fe8bd497d74a 100644 --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -304,19 +304,10 @@ static void nft_rbtree_set_start_cookie(struct nft_rbtree *priv, priv->start_rbe_cookie = (unsigned long)rbe; } -static void nft_rbtree_set_start_cookie_open(struct nft_rbtree *priv, - const struct nft_rbtree_elem *rbe, - unsigned long open_interval) -{ - priv->start_rbe_cookie = (unsigned long)rbe | open_interval; -} - -#define NFT_RBTREE_OPEN_INTERVAL 1UL - static bool nft_rbtree_cmp_start_cookie(struct nft_rbtree *priv, const struct nft_rbtree_elem *rbe) { - return (priv->start_rbe_cookie & ~NFT_RBTREE_OPEN_INTERVAL) == (unsigned long)rbe; + return priv->start_rbe_cookie == (unsigned long)rbe; } static bool nft_rbtree_insert_same_interval(const struct net *net, @@ -346,14 +337,13 @@ static bool nft_rbtree_insert_same_interval(const struct net *net, static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set, struct nft_rbtree_elem *new, - struct nft_elem_priv **elem_priv, u64 tstamp, bool last) + struct nft_elem_priv **elem_priv, u64 tstamp) { struct nft_rbtree_elem *rbe, *rbe_le = NULL, *rbe_ge = NULL, *rbe_prev; struct rb_node *node, *next, *parent, **p, *first = NULL; struct nft_rbtree *priv = nft_set_priv(set); u8 cur_genmask = nft_genmask_cur(net); u8 genmask = nft_genmask_next(net); - unsigned long open_interval = 0; int d; /* Descend the tree to search for an existing element greater than the @@ -459,18 +449,10 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set, } } - if (nft_rbtree_interval_null(set, new)) { + if (nft_rbtree_interval_null(set, new)) + priv->start_rbe_cookie = 0; + else if (nft_rbtree_interval_start(new) && priv->start_rbe_cookie) priv->start_rbe_cookie = 0; - } else if (nft_rbtree_interval_start(new) && priv->start_rbe_cookie) { - if (nft_set_is_anonymous(set)) { - priv->start_rbe_cookie = 0; - } else if (priv->start_rbe_cookie & NFT_RBTREE_OPEN_INTERVAL) { - /* Previous element is an open interval that partially - * overlaps with an existing non-open interval. - */ - return -ENOTEMPTY; - } - } /* - new start element matching existing start element: full overlap * reported as -EEXIST, cleared by caller if NLM_F_EXCL is not given. @@ -478,27 +460,7 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set, if (rbe_ge && !nft_rbtree_cmp(set, new, rbe_ge) && nft_rbtree_interval_start(rbe_ge) == nft_rbtree_interval_start(new)) { *elem_priv = &rbe_ge->priv; - - /* - Corner case: new start element of open interval (which - * comes as last element in the batch) overlaps the start of - * an existing interval with an end element: partial overlap. - */ - node = rb_first(&priv->root); - rbe = __nft_rbtree_next_active(node, genmask); - if (rbe && nft_rbtree_interval_end(rbe)) { - rbe = nft_rbtree_next_active(rbe, genmask); - if (rbe && - nft_rbtree_interval_start(rbe) && - !nft_rbtree_cmp(set, new, rbe)) { - if (last) - return -ENOTEMPTY; - - /* Maybe open interval? */ - open_interval = NFT_RBTREE_OPEN_INTERVAL; - } - } - nft_rbtree_set_start_cookie_open(priv, rbe_ge, open_interval); - + nft_rbtree_set_start_cookie(priv, rbe_ge); return -EEXIST; } @@ -553,12 +515,6 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set, nft_rbtree_interval_end(rbe_ge) && nft_rbtree_interval_end(new)) return -ENOTEMPTY; - /* - start element overlaps an open interval but end element is new: - * partial overlap, reported as -ENOEMPTY. - */ - if (!rbe_ge && priv->start_rbe_cookie && nft_rbtree_interval_end(new)) - return -ENOTEMPTY; - /* Accepted element: pick insertion point depending on key value */ parent = NULL; p = &priv->root.rb_node; @@ -668,7 +624,6 @@ static int nft_rbtree_insert(const struct net *net, const struct nft_set *set, struct nft_elem_priv **elem_priv) { struct nft_rbtree_elem *rbe = nft_elem_priv_cast(elem->priv); - bool last = !!(elem->flags & NFT_SET_ELEM_INTERNAL_LAST); struct nft_rbtree *priv = nft_set_priv(set); u64 tstamp = nft_net_tstamp(net); int err; @@ -685,12 +640,8 @@ static int nft_rbtree_insert(const struct net *net, const struct nft_set *set, cond_resched(); write_lock_bh(&priv->lock); - err = __nft_rbtree_insert(net, set, rbe, elem_priv, tstamp, last); + err = __nft_rbtree_insert(net, set, rbe, elem_priv, tstamp); write_unlock_bh(&priv->lock); - - if (nft_rbtree_interval_end(rbe)) - priv->start_rbe_cookie = 0; - } while (err == -EAGAIN); return err; @@ -778,7 +729,6 @@ nft_rbtree_deactivate(const struct net *net, const struct nft_set *set, const struct nft_set_elem *elem) { struct nft_rbtree_elem *rbe, *this = nft_elem_priv_cast(elem->priv); - bool last = !!(elem->flags & NFT_SET_ELEM_INTERNAL_LAST); struct nft_rbtree *priv = nft_set_priv(set); const struct rb_node *parent = priv->root.rb_node; u8 genmask = nft_genmask_next(net); @@ -819,10 +769,9 @@ nft_rbtree_deactivate(const struct net *net, const struct nft_set *set, continue; } - if (nft_rbtree_interval_start(rbe)) { - if (!last) - nft_rbtree_set_start_cookie(priv, rbe); - } else if (!nft_rbtree_deactivate_same_interval(net, priv, rbe)) + if (nft_rbtree_interval_start(rbe)) + nft_rbtree_set_start_cookie(priv, rbe); + else if (!nft_rbtree_deactivate_same_interval(net, priv, rbe)) return NULL; nft_rbtree_flush(net, set, &rbe->priv); -- cgit v1.2.3 From a3aca98aec9a278ee56da4f8013bfa1dd1a1c298 Mon Sep 17 00:00:00 2001 From: Eric Woudstra Date: Tue, 10 Mar 2026 15:39:33 +0100 Subject: netfilter: nf_flow_table_ip: reset mac header before vlan push With double vlan tagged packets in the fastpath, getting the error: skb_vlan_push got skb with skb->data not at mac header (offset 18) Call skb_reset_mac_header() before calling skb_vlan_push(). Fixes: c653d5a78f34 ("netfilter: flowtable: inline vlan encapsulation in xmit path") Signed-off-by: Eric Woudstra Acked-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/nf_flow_table_ip.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c index 3fdb10d9bf7f..fd56d663cb5b 100644 --- a/net/netfilter/nf_flow_table_ip.c +++ b/net/netfilter/nf_flow_table_ip.c @@ -738,6 +738,7 @@ static int nf_flow_encap_push(struct sk_buff *skb, switch (tuple->encap[i].proto) { case htons(ETH_P_8021Q): case htons(ETH_P_8021AD): + skb_reset_mac_header(skb); if (skb_vlan_push(skb, tuple->encap[i].proto, tuple->encap[i].id) < 0) return -1; -- cgit v1.2.3 From 1e3a3593162c96e8a8de48b1e14f60c3b57fca8a Mon Sep 17 00:00:00 2001 From: Jenny Guanni Qu Date: Thu, 12 Mar 2026 02:29:32 +0000 Subject: netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In decode_int(), the CONS case calls get_bits(bs, 2) to read a length value, then calls get_uint(bs, len) without checking that len bytes remain in the buffer. The existing boundary check only validates the 2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint() reads. This allows a malformed H.323/RAS packet to cause a 1-4 byte slab-out-of-bounds read. Add a boundary check for len bytes after get_bits() and before get_uint(). Fixes: 5e35941d9901 ("[NETFILTER]: Add H.323 conntrack/NAT helper") Reported-by: Klaudia Kloc Reported-by: Dawid Moczadło Signed-off-by: Jenny Guanni Qu Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_h323_asn1.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_h323_asn1.c b/net/netfilter/nf_conntrack_h323_asn1.c index 62aa22a07876..c972e9488e16 100644 --- a/net/netfilter/nf_conntrack_h323_asn1.c +++ b/net/netfilter/nf_conntrack_h323_asn1.c @@ -331,6 +331,8 @@ static int decode_int(struct bitstr *bs, const struct field_t *f, if (nf_h323_error_boundary(bs, 0, 2)) return H323_ERROR_BOUND; len = get_bits(bs, 2) + 1; + if (nf_h323_error_boundary(bs, len, 0)) + return H323_ERROR_BOUND; BYTE_ALIGN(bs); if (base && (f->attr & DECODE)) { /* timeToLive */ unsigned int v = get_uint(bs, len) + f->lb; -- cgit v1.2.3 From 0548a13b5a145b16e4da0628b5936baf35f51b43 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 12 Mar 2026 12:38:59 +0100 Subject: nf_tables: nft_dynset: fix possible stateful expression memleak in error path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If cloning the second stateful expression in the element via GFP_ATOMIC fails, then the first stateful expression remains in place without being released.   unreferenced object (percpu) 0x607b97e9cab8 (size 16):     comm "softirq", pid 0, jiffies 4294931867     hex dump (first 16 bytes on cpu 3):       00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     backtrace (crc 0):       pcpu_alloc_noprof+0x453/0xd80       nft_counter_clone+0x9c/0x190 [nf_tables]       nft_expr_clone+0x8f/0x1b0 [nf_tables]       nft_dynset_new+0x2cb/0x5f0 [nf_tables]       nft_rhash_update+0x236/0x11c0 [nf_tables]       nft_dynset_eval+0x11f/0x670 [nf_tables]       nft_do_chain+0x253/0x1700 [nf_tables]       nft_do_chain_ipv4+0x18d/0x270 [nf_tables]       nf_hook_slow+0xaa/0x1e0       ip_local_deliver+0x209/0x330 Fixes: 563125a73ac3 ("netfilter: nftables: generalize set extension to support for several expressions") Reported-by: Gurpreet Shergill Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- include/net/netfilter/nf_tables.h | 2 ++ net/netfilter/nf_tables_api.c | 4 ++-- net/netfilter/nft_dynset.c | 10 +++++++++- 3 files changed, 13 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 6299af4ef423..ec8a8ec9c0aa 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -874,6 +874,8 @@ struct nft_elem_priv *nft_set_elem_init(const struct nft_set *set, u64 timeout, u64 expiration, gfp_t gfp); int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set, struct nft_expr *expr_array[]); +void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, + struct nft_set_elem_expr *elem_expr); void nft_set_elem_destroy(const struct nft_set *set, const struct nft_elem_priv *elem_priv, bool destroy_expr); diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 4ccdd33cf133..9b1c8d0a35fb 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -6744,8 +6744,8 @@ static void __nft_set_elem_expr_destroy(const struct nft_ctx *ctx, } } -static void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, - struct nft_set_elem_expr *elem_expr) +void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, + struct nft_set_elem_expr *elem_expr) { struct nft_expr *expr; u32 size; diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index 7807d8129664..9123277be03c 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -30,18 +30,26 @@ static int nft_dynset_expr_setup(const struct nft_dynset *priv, const struct nft_set_ext *ext) { struct nft_set_elem_expr *elem_expr = nft_set_ext_expr(ext); + struct nft_ctx ctx = { + .net = read_pnet(&priv->set->net), + .family = priv->set->table->family, + }; struct nft_expr *expr; int i; for (i = 0; i < priv->num_exprs; i++) { expr = nft_setelem_expr_at(elem_expr, elem_expr->size); if (nft_expr_clone(expr, priv->expr_array[i], GFP_ATOMIC) < 0) - return -1; + goto err_out; elem_expr->size += priv->expr_array[i]->ops->size; } return 0; +err_out: + nft_set_elem_expr_destroy(&ctx, elem_expr); + + return -1; } struct nft_elem_priv *nft_dynset_new(struct nft_set *set, -- cgit v1.2.3 From 36eae0956f659e48d5366d9b083d9417f3263ddc Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 12 Mar 2026 13:48:47 +0100 Subject: netfilter: nft_ct: drop pending enqueued packets on removal Packets sitting in nfqueue might hold a reference to: - templates that specify the conntrack zone, because a percpu area is used and module removal is possible. - conntrack timeout policies and helper, where object removal leave a stale reference. Since these objects can just go away, drop enqueued packets to avoid stale reference to them. If there is a need for finer grain removal, this logic can be revisited to make selective packet drop upon dependencies. Fixes: 7e0b2b57f01d ("netfilter: nft_ct: add ct timeout support") Reported-by: Yiming Qian Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/nft_ct.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 47d3ef109a99..128ff8155b5d 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -23,6 +23,7 @@ #include #include #include +#include "nf_internals.h" struct nft_ct_helper_obj { struct nf_conntrack_helper *helper4; @@ -543,6 +544,7 @@ static void __nft_ct_set_destroy(const struct nft_ctx *ctx, struct nft_ct *priv) #endif #ifdef CONFIG_NF_CONNTRACK_ZONES case NFT_CT_ZONE: + nf_queue_nf_hook_drop(ctx->net); mutex_lock(&nft_ct_pcpu_mutex); if (--nft_ct_pcpu_template_refcnt == 0) nft_ct_tmpl_put_pcpu(); @@ -1015,6 +1017,7 @@ static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx, struct nft_ct_timeout_obj *priv = nft_obj_data(obj); struct nf_ct_timeout *timeout = priv->timeout; + nf_queue_nf_hook_drop(ctx->net); nf_ct_untimeout(ctx->net, timeout); nf_ct_netns_put(ctx->net, ctx->family); kfree(priv->timeout); @@ -1147,6 +1150,7 @@ static void nft_ct_helper_obj_destroy(const struct nft_ctx *ctx, { struct nft_ct_helper_obj *priv = nft_obj_data(obj); + nf_queue_nf_hook_drop(ctx->net); if (priv->helper4) nf_conntrack_helper_put(priv->helper4); if (priv->helper6) -- cgit v1.2.3 From f62a218a946b19bb59abdd5361da85fa4606b96b Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 12 Mar 2026 13:48:48 +0100 Subject: netfilter: xt_CT: drop pending enqueued packets on template removal Templates refer to objects that can go away while packets are sitting in nfqueue refer to: - helper, this can be an issue on module removal. - timeout policy, nfnetlink_cttimeout might remove it. The use of templates with zone and event cache filter are safe, since this just copies values. Flush these enqueued packets in case the template rule gets removed. Fixes: 24de58f46516 ("netfilter: xt_CT: allow to attach timeout policy + glue code") Reported-by: Yiming Qian Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/xt_CT.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/netfilter/xt_CT.c b/net/netfilter/xt_CT.c index 3ba94c34297c..498f5871c84a 100644 --- a/net/netfilter/xt_CT.c +++ b/net/netfilter/xt_CT.c @@ -16,6 +16,7 @@ #include #include #include +#include "nf_internals.h" static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct) { @@ -283,6 +284,9 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par, struct nf_conn_help *help; if (ct) { + if (info->helper[0] || info->timeout[0]) + nf_queue_nf_hook_drop(par->net); + help = nfct_help(ct); xt_ct_put_helper(help); -- cgit v1.2.3 From 00050ec08cecfda447e1209b388086d76addda3a Mon Sep 17 00:00:00 2001 From: Jenny Guanni Qu Date: Thu, 12 Mar 2026 14:59:49 +0000 Subject: netfilter: xt_time: use unsigned int for monthday bit shift MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The monthday field can be up to 31, and shifting a signed integer 1 by 31 positions (1 << 31) is undefined behavior in C, as the result overflows a 32-bit signed int. Use 1U to ensure well-defined behavior for all valid monthday values. Change the weekday shift to 1U as well for consistency. Fixes: ee4411a1b1e0 ("[NETFILTER]: x_tables: add xt_time match") Reported-by: Klaudia Kloc Reported-by: Dawid Moczadło Tested-by: Jenny Guanni Qu Signed-off-by: Jenny Guanni Qu Signed-off-by: Florian Westphal --- net/netfilter/xt_time.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/netfilter/xt_time.c b/net/netfilter/xt_time.c index 00319d2a54da..d9d74011bb64 100644 --- a/net/netfilter/xt_time.c +++ b/net/netfilter/xt_time.c @@ -223,13 +223,13 @@ time_mt(const struct sk_buff *skb, struct xt_action_param *par) localtime_2(¤t_time, stamp); - if (!(info->weekdays_match & (1 << current_time.weekday))) + if (!(info->weekdays_match & (1U << current_time.weekday))) return false; /* Do not spend time computing monthday if all days match anyway */ if (info->monthdays_match != XT_TIME_ALL_MONTHDAYS) { localtime_3(¤t_time, stamp); - if (!(info->monthdays_match & (1 << current_time.monthday))) + if (!(info->monthdays_match & (1U << current_time.monthday))) return false; } -- cgit v1.2.3 From f173d0f4c0f689173f8cdac79991043a4a89bf66 Mon Sep 17 00:00:00 2001 From: Jenny Guanni Qu Date: Thu, 12 Mar 2026 14:49:50 +0000 Subject: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In DecodeQ931(), the UserUserIE code path reads a 16-bit length from the packet, then decrements it by 1 to skip the protocol discriminator byte before passing it to DecodeH323_UserInformation(). If the encoded length is 0, the decrement wraps to -1, which is then passed as a large value to the decoder, leading to an out-of-bounds read. Add a check to ensure len is positive after the decrement. Fixes: 5e35941d9901 ("[NETFILTER]: Add H.323 conntrack/NAT helper") Reported-by: Klaudia Kloc Reported-by: Dawid Moczadło Tested-by: Jenny Guanni Qu Signed-off-by: Jenny Guanni Qu Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_h323_asn1.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_h323_asn1.c b/net/netfilter/nf_conntrack_h323_asn1.c index c972e9488e16..7b1497ed97d2 100644 --- a/net/netfilter/nf_conntrack_h323_asn1.c +++ b/net/netfilter/nf_conntrack_h323_asn1.c @@ -924,6 +924,8 @@ int DecodeQ931(unsigned char *buf, size_t sz, Q931 *q931) break; p++; len--; + if (len <= 0) + break; return DecodeH323_UserInformation(buf, p, len, &q931->UUIE); } -- cgit v1.2.3 From 0d4aef630be9d5f9c1227d07669c26c4383b5ad0 Mon Sep 17 00:00:00 2001 From: Yang Yang Date: Sat, 14 Mar 2026 07:11:27 +0000 Subject: batman-adv: avoid OGM aggregation when skb tailroom is insufficient When OGM aggregation state is toggled at runtime, an existing forwarded packet may have been allocated with only packet_len bytes, while a later packet can still be selected for aggregation. Appending in this case can hit skb_put overflow conditions. Reject aggregation when the target skb tailroom cannot accommodate the new packet. The caller then falls back to creating a new forward packet instead of appending. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Cc: stable@vger.kernel.org Reported-by: Yifan Wu Reported-by: Juefei Pu Signed-off-by: Yuan Tan Signed-off-by: Xin Liu Signed-off-by: Ao Zhou Signed-off-by: Yang Yang Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich --- net/batman-adv/bat_iv_ogm.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net') diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index b75c2228e69a..f28e9cbf8ad5 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -473,6 +473,9 @@ batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet, if (aggregated_bytes > max_bytes) return false; + if (skb_tailroom(forw_packet->skb) < packet_len) + return false; + if (packet_num >= BATADV_MAX_AGGREGATION_PACKETS) return false; -- cgit v1.2.3 From 922814879542c2e397b0e9641fd36b8202a8e555 Mon Sep 17 00:00:00 2001 From: Deepanshu Kartikey Date: Mon, 9 Mar 2026 21:29:08 +0530 Subject: atm: lec: fix use-after-free in sock_def_readable() A race condition exists between lec_atm_close() setting priv->lecd to NULL and concurrent access to priv->lecd in send_to_lecd(), lec_handle_bridge(), and lec_atm_send(). When the socket is freed via RCU while another thread is still using it, a use-after-free occurs in sock_def_readable() when accessing the socket's wait queue. The root cause is that lec_atm_close() clears priv->lecd without any synchronization, while callers dereference priv->lecd without any protection against concurrent teardown. Fix this by converting priv->lecd to an RCU-protected pointer: - Mark priv->lecd as __rcu in lec.h - Use rcu_assign_pointer() in lec_atm_close() and lecd_attach() for safe pointer assignment - Use rcu_access_pointer() for NULL checks that do not dereference the pointer in lec_start_xmit(), lec_push(), send_to_lecd() and lecd_attach() - Use rcu_read_lock/rcu_dereference/rcu_read_unlock in send_to_lecd(), lec_handle_bridge() and lec_atm_send() to safely access lecd - Use rcu_assign_pointer() followed by synchronize_rcu() in lec_atm_close() to ensure all readers have completed before proceeding. This is safe since lec_atm_close() is called from vcc_release() which holds lock_sock(), a sleeping lock. - Remove the manual sk_receive_queue drain from lec_atm_close() since vcc_destroy_socket() already drains it after lec_atm_close() returns. v2: Switch from spinlock + sock_hold/put approach to RCU to properly fix the race. The v1 spinlock approach had two issues pointed out by Eric Dumazet: 1. priv->lecd was still accessed directly after releasing the lock instead of using a local copy. 2. The spinlock did not prevent packets being queued after lec_atm_close() drains sk_receive_queue since timer and workqueue paths bypass netif_stop_queue(). Note: Syzbot patch testing was attempted but the test VM terminated unexpectedly with "Connection to localhost closed by remote host", likely due to a QEMU AHCI emulation issue unrelated to this fix. Compile testing with "make W=1 net/atm/lec.o" passes cleanly. Reported-by: syzbot+f50072212ab792c86925@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=f50072212ab792c86925 Link: https://lore.kernel.org/all/20260309093614.502094-1-kartikey406@gmail.com/T/ [v1] Signed-off-by: Deepanshu Kartikey Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260309155908.508768-1-kartikey406@gmail.com Signed-off-by: Jakub Kicinski --- net/atm/lec.c | 72 ++++++++++++++++++++++++++++++++++++++--------------------- net/atm/lec.h | 2 +- 2 files changed, 48 insertions(+), 26 deletions(-) (limited to 'net') diff --git a/net/atm/lec.c b/net/atm/lec.c index fb93c6e1c329..10e260acf602 100644 --- a/net/atm/lec.c +++ b/net/atm/lec.c @@ -154,10 +154,19 @@ static void lec_handle_bridge(struct sk_buff *skb, struct net_device *dev) /* 0x01 is topology change */ priv = netdev_priv(dev); - atm_force_charge(priv->lecd, skb2->truesize); - sk = sk_atm(priv->lecd); - skb_queue_tail(&sk->sk_receive_queue, skb2); - sk->sk_data_ready(sk); + struct atm_vcc *vcc; + + rcu_read_lock(); + vcc = rcu_dereference(priv->lecd); + if (vcc) { + atm_force_charge(vcc, skb2->truesize); + sk = sk_atm(vcc); + skb_queue_tail(&sk->sk_receive_queue, skb2); + sk->sk_data_ready(sk); + } else { + dev_kfree_skb(skb2); + } + rcu_read_unlock(); } } #endif /* IS_ENABLED(CONFIG_BRIDGE) */ @@ -216,7 +225,7 @@ static netdev_tx_t lec_start_xmit(struct sk_buff *skb, int is_rdesc; pr_debug("called\n"); - if (!priv->lecd) { + if (!rcu_access_pointer(priv->lecd)) { pr_info("%s:No lecd attached\n", dev->name); dev->stats.tx_errors++; netif_stop_queue(dev); @@ -449,10 +458,19 @@ static int lec_atm_send(struct atm_vcc *vcc, struct sk_buff *skb) break; skb2->len = sizeof(struct atmlec_msg); skb_copy_to_linear_data(skb2, mesg, sizeof(*mesg)); - atm_force_charge(priv->lecd, skb2->truesize); - sk = sk_atm(priv->lecd); - skb_queue_tail(&sk->sk_receive_queue, skb2); - sk->sk_data_ready(sk); + struct atm_vcc *vcc; + + rcu_read_lock(); + vcc = rcu_dereference(priv->lecd); + if (vcc) { + atm_force_charge(vcc, skb2->truesize); + sk = sk_atm(vcc); + skb_queue_tail(&sk->sk_receive_queue, skb2); + sk->sk_data_ready(sk); + } else { + dev_kfree_skb(skb2); + } + rcu_read_unlock(); } } #endif /* IS_ENABLED(CONFIG_BRIDGE) */ @@ -468,23 +486,16 @@ static int lec_atm_send(struct atm_vcc *vcc, struct sk_buff *skb) static void lec_atm_close(struct atm_vcc *vcc) { - struct sk_buff *skb; struct net_device *dev = (struct net_device *)vcc->proto_data; struct lec_priv *priv = netdev_priv(dev); - priv->lecd = NULL; + rcu_assign_pointer(priv->lecd, NULL); + synchronize_rcu(); /* Do something needful? */ netif_stop_queue(dev); lec_arp_destroy(priv); - if (skb_peek(&sk_atm(vcc)->sk_receive_queue)) - pr_info("%s closing with messages pending\n", dev->name); - while ((skb = skb_dequeue(&sk_atm(vcc)->sk_receive_queue))) { - atm_return(vcc, skb->truesize); - dev_kfree_skb(skb); - } - pr_info("%s: Shut down!\n", dev->name); module_put(THIS_MODULE); } @@ -510,12 +521,14 @@ send_to_lecd(struct lec_priv *priv, atmlec_msg_type type, const unsigned char *mac_addr, const unsigned char *atm_addr, struct sk_buff *data) { + struct atm_vcc *vcc; struct sock *sk; struct sk_buff *skb; struct atmlec_msg *mesg; - if (!priv || !priv->lecd) + if (!priv || !rcu_access_pointer(priv->lecd)) return -1; + skb = alloc_skb(sizeof(struct atmlec_msg), GFP_ATOMIC); if (!skb) return -1; @@ -532,18 +545,27 @@ send_to_lecd(struct lec_priv *priv, atmlec_msg_type type, if (atm_addr) memcpy(&mesg->content.normal.atm_addr, atm_addr, ATM_ESA_LEN); - atm_force_charge(priv->lecd, skb->truesize); - sk = sk_atm(priv->lecd); + rcu_read_lock(); + vcc = rcu_dereference(priv->lecd); + if (!vcc) { + rcu_read_unlock(); + kfree_skb(skb); + return -1; + } + + atm_force_charge(vcc, skb->truesize); + sk = sk_atm(vcc); skb_queue_tail(&sk->sk_receive_queue, skb); sk->sk_data_ready(sk); if (data != NULL) { pr_debug("about to send %d bytes of data\n", data->len); - atm_force_charge(priv->lecd, data->truesize); + atm_force_charge(vcc, data->truesize); skb_queue_tail(&sk->sk_receive_queue, data); sk->sk_data_ready(sk); } + rcu_read_unlock(); return 0; } @@ -618,7 +640,7 @@ static void lec_push(struct atm_vcc *vcc, struct sk_buff *skb) atm_return(vcc, skb->truesize); if (*(__be16 *) skb->data == htons(priv->lecid) || - !priv->lecd || !(dev->flags & IFF_UP)) { + !rcu_access_pointer(priv->lecd) || !(dev->flags & IFF_UP)) { /* * Probably looping back, or if lecd is missing, * lecd has gone down @@ -753,12 +775,12 @@ static int lecd_attach(struct atm_vcc *vcc, int arg) priv = netdev_priv(dev_lec[i]); } else { priv = netdev_priv(dev_lec[i]); - if (priv->lecd) + if (rcu_access_pointer(priv->lecd)) return -EADDRINUSE; } lec_arp_init(priv); priv->itfnum = i; /* LANE2 addition */ - priv->lecd = vcc; + rcu_assign_pointer(priv->lecd, vcc); vcc->dev = &lecatm_dev; vcc_insert_socket(sk_atm(vcc)); diff --git a/net/atm/lec.h b/net/atm/lec.h index be0e2667bd8c..ec85709bf818 100644 --- a/net/atm/lec.h +++ b/net/atm/lec.h @@ -91,7 +91,7 @@ struct lec_priv { */ spinlock_t lec_arp_lock; struct atm_vcc *mcast_vcc; /* Default Multicast Send VCC */ - struct atm_vcc *lecd; + struct atm_vcc __rcu *lecd; struct delayed_work lec_arp_work; /* C10 */ unsigned int maximum_unknown_frame_count; /* -- cgit v1.2.3 From 17ad31b3a43b72aec3a3d83605891e1397d0d065 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Mon, 23 Feb 2026 12:09:58 -0500 Subject: sunrpc: fix cache_request leak in cache_release When a reader's file descriptor is closed while in the middle of reading a cache_request (rp->offset != 0), cache_release() decrements the request's readers count but never checks whether it should free the request. In cache_read(), when readers drops to 0 and CACHE_PENDING is clear, the cache_request is removed from the queue and freed along with its buffer and cache_head reference. cache_release() lacks this cleanup. The only other path that frees requests with readers == 0 is cache_dequeue(), but it runs only when CACHE_PENDING transitions from set to clear. If that transition already happened while readers was still non-zero, cache_dequeue() will have skipped the request, and no subsequent call will clean it up. Add the same cleanup logic from cache_read() to cache_release(): after decrementing readers, check if it reached 0 with CACHE_PENDING clear, and if so, dequeue and free the cache_request. Reported-by: NeilBrown Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@kernel.org Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever --- net/sunrpc/cache.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 131090f31e6a..6f6e0d4928af 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -1061,14 +1061,25 @@ static int cache_release(struct inode *inode, struct file *filp, struct cache_reader *rp = filp->private_data; if (rp) { + struct cache_request *rq = NULL; + spin_lock(&queue_lock); if (rp->offset) { struct cache_queue *cq; - for (cq= &rp->q; &cq->list != &cd->queue; - cq = list_entry(cq->list.next, struct cache_queue, list)) + for (cq = &rp->q; &cq->list != &cd->queue; + cq = list_entry(cq->list.next, + struct cache_queue, list)) if (!cq->reader) { - container_of(cq, struct cache_request, q) - ->readers--; + struct cache_request *cr = + container_of(cq, + struct cache_request, q); + cr->readers--; + if (cr->readers == 0 && + !test_bit(CACHE_PENDING, + &cr->item->flags)) { + list_del(&cr->q.list); + rq = cr; + } break; } rp->offset = 0; @@ -1076,9 +1087,14 @@ static int cache_release(struct inode *inode, struct file *filp, list_del(&rp->q.list); spin_unlock(&queue_lock); + if (rq) { + cache_put(rq->item, cd); + kfree(rq->buf); + kfree(rq); + } + filp->private_data = NULL; kfree(rp); - } if (filp->f_mode & FMODE_WRITE) { atomic_dec(&cd->writers); -- cgit v1.2.3 From b7405dcf7385445e10821777143f18c3ce20fa04 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 15 Mar 2026 10:41:52 +0000 Subject: bonding: prevent potential infinite loop in bond_header_parse() bond_header_parse() can loop if a stack of two bonding devices is setup, because skb->dev always points to the hierarchy top. Add new "const struct net_device *dev" parameter to (struct header_ops)->parse() method to make sure the recursion is bounded, and that the final leaf parse method is called. Fixes: 950803f72547 ("bonding: fix type confusion in bond_setup_by_slave()") Signed-off-by: Eric Dumazet Reviewed-by: Jiayuan Chen Tested-by: Jiayuan Chen Cc: Jay Vosburgh Cc: Andrew Lunn Link: https://patch.msgid.link/20260315104152.1436867-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- drivers/firewire/net.c | 5 +++-- drivers/net/bonding/bond_main.c | 8 +++++--- include/linux/etherdevice.h | 3 ++- include/linux/if_ether.h | 3 ++- include/linux/netdevice.h | 6 ++++-- net/ethernet/eth.c | 9 +++------ net/ipv4/ip_gre.c | 3 ++- net/mac802154/iface.c | 4 +++- net/phonet/af_phonet.c | 5 ++++- 9 files changed, 28 insertions(+), 18 deletions(-) (limited to 'net') diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c index f1a2bee39bf1..82b3b6d9ed2d 100644 --- a/drivers/firewire/net.c +++ b/drivers/firewire/net.c @@ -257,9 +257,10 @@ static void fwnet_header_cache_update(struct hh_cache *hh, memcpy((u8 *)hh->hh_data + HH_DATA_OFF(FWNET_HLEN), haddr, net->addr_len); } -static int fwnet_header_parse(const struct sk_buff *skb, unsigned char *haddr) +static int fwnet_header_parse(const struct sk_buff *skb, const struct net_device *dev, + unsigned char *haddr) { - memcpy(haddr, skb->dev->dev_addr, FWNET_ALEN); + memcpy(haddr, dev->dev_addr, FWNET_ALEN); return FWNET_ALEN; } diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 707419270ebf..33f414d03ab9 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1530,9 +1530,11 @@ static int bond_header_create(struct sk_buff *skb, struct net_device *bond_dev, return ret; } -static int bond_header_parse(const struct sk_buff *skb, unsigned char *haddr) +static int bond_header_parse(const struct sk_buff *skb, + const struct net_device *dev, + unsigned char *haddr) { - struct bonding *bond = netdev_priv(skb->dev); + struct bonding *bond = netdev_priv(dev); const struct header_ops *slave_ops; struct slave *slave; int ret = 0; @@ -1542,7 +1544,7 @@ static int bond_header_parse(const struct sk_buff *skb, unsigned char *haddr) if (slave) { slave_ops = READ_ONCE(slave->dev->header_ops); if (slave_ops && slave_ops->parse) - ret = slave_ops->parse(skb, haddr); + ret = slave_ops->parse(skb, slave->dev, haddr); } rcu_read_unlock(); return ret; diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 9a1eacf35d37..df8f88f63a70 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -42,7 +42,8 @@ extern const struct header_ops eth_header_ops; int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned len); -int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr); +int eth_header_parse(const struct sk_buff *skb, const struct net_device *dev, + unsigned char *haddr); int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type); void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev, diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h index 61b7335aa037..ca9afa824aa4 100644 --- a/include/linux/if_ether.h +++ b/include/linux/if_ether.h @@ -40,7 +40,8 @@ static inline struct ethhdr *inner_eth_hdr(const struct sk_buff *skb) return (struct ethhdr *)skb_inner_mac_header(skb); } -int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr); +int eth_header_parse(const struct sk_buff *skb, const struct net_device *dev, + unsigned char *haddr); extern ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len); diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d7aac6f185bc..7ca01eb3f7d2 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -311,7 +311,9 @@ struct header_ops { int (*create) (struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len); - int (*parse)(const struct sk_buff *skb, unsigned char *haddr); + int (*parse)(const struct sk_buff *skb, + const struct net_device *dev, + unsigned char *haddr); int (*cache)(const struct neighbour *neigh, struct hh_cache *hh, __be16 type); void (*cache_update)(struct hh_cache *hh, const struct net_device *dev, @@ -3445,7 +3447,7 @@ static inline int dev_parse_header(const struct sk_buff *skb, if (!dev->header_ops || !dev->header_ops->parse) return 0; - return dev->header_ops->parse(skb, haddr); + return dev->header_ops->parse(skb, dev, haddr); } static inline __be16 dev_parse_header_protocol(const struct sk_buff *skb) diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 13a63b48b7ee..d9faadbe9b6c 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -193,14 +193,11 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) } EXPORT_SYMBOL(eth_type_trans); -/** - * eth_header_parse - extract hardware address from packet - * @skb: packet to extract header from - * @haddr: destination buffer - */ -int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr) +int eth_header_parse(const struct sk_buff *skb, const struct net_device *dev, + unsigned char *haddr) { const struct ethhdr *eth = eth_hdr(skb); + memcpy(haddr, eth->h_source, ETH_ALEN); return ETH_ALEN; } diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index e13244729ad8..35f0baa99d40 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -919,7 +919,8 @@ static int ipgre_header(struct sk_buff *skb, struct net_device *dev, return -(t->hlen + sizeof(*iph)); } -static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) +static int ipgre_header_parse(const struct sk_buff *skb, const struct net_device *dev, + unsigned char *haddr) { const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); memcpy(haddr, &iph->saddr, 4); diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c index 9e4631fade90..000be60d9580 100644 --- a/net/mac802154/iface.c +++ b/net/mac802154/iface.c @@ -469,7 +469,9 @@ static int mac802154_header_create(struct sk_buff *skb, } static int -mac802154_header_parse(const struct sk_buff *skb, unsigned char *haddr) +mac802154_header_parse(const struct sk_buff *skb, + const struct net_device *dev, + unsigned char *haddr) { struct ieee802154_hdr hdr; diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c index 238a9638d2b0..d89225d6bfd3 100644 --- a/net/phonet/af_phonet.c +++ b/net/phonet/af_phonet.c @@ -129,9 +129,12 @@ static int pn_header_create(struct sk_buff *skb, struct net_device *dev, return 1; } -static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr) +static int pn_header_parse(const struct sk_buff *skb, + const struct net_device *dev, + unsigned char *haddr) { const u8 *media = skb_mac_header(skb); + *haddr = *media; return 1; } -- cgit v1.2.3 From 6d5e4538364b9ceb1ac2941a4deb86650afb3538 Mon Sep 17 00:00:00 2001 From: Jiayuan Chen Date: Thu, 12 Mar 2026 17:29:07 +0800 Subject: net/smc: fix NULL dereference and UAF in smc_tcp_syn_recv_sock() Syzkaller reported a panic in smc_tcp_syn_recv_sock() [1]. smc_tcp_syn_recv_sock() is called in the TCP receive path (softirq) via icsk_af_ops->syn_recv_sock on the clcsock (TCP listening socket). It reads sk_user_data to get the smc_sock pointer. However, when the SMC listen socket is being closed concurrently, smc_close_active() sets clcsock->sk_user_data to NULL under sk_callback_lock, and then the smc_sock itself can be freed via sock_put() in smc_release(). This leads to two issues: 1) NULL pointer dereference: sk_user_data is NULL when accessed. 2) Use-after-free: sk_user_data is read as non-NULL, but the smc_sock is freed before its fields (e.g., queued_smc_hs, ori_af_ops) are accessed. The race window looks like this (the syzkaller crash [1] triggers via the SYN cookie path: tcp_get_cookie_sock() -> smc_tcp_syn_recv_sock(), but the normal tcp_check_req() path has the same race): CPU A (softirq) CPU B (process ctx) tcp_v4_rcv() TCP_NEW_SYN_RECV: sk = req->rsk_listener sock_hold(sk) /* No lock on listener */ smc_close_active(): write_lock_bh(cb_lock) sk_user_data = NULL write_unlock_bh(cb_lock) ... smc_clcsock_release() sock_put(smc->sk) x2 -> smc_sock freed! tcp_check_req() smc_tcp_syn_recv_sock(): smc = user_data(sk) -> NULL or dangling smc->queued_smc_hs -> crash! Note that the clcsock and smc_sock are two independent objects with separate refcounts. TCP stack holds a reference on the clcsock, which keeps it alive, but this does NOT prevent the smc_sock from being freed. Fix this by using RCU and refcount_inc_not_zero() to safely access smc_sock. Since smc_tcp_syn_recv_sock() is called in the TCP three-way handshake path, taking read_lock_bh on sk_callback_lock is too heavy and would not survive a SYN flood attack. Using rcu_read_lock() is much more lightweight. - Set SOCK_RCU_FREE on the SMC listen socket so that smc_sock freeing is deferred until after the RCU grace period. This guarantees the memory is still valid when accessed inside rcu_read_lock(). - Use rcu_read_lock() to protect reading sk_user_data. - Use refcount_inc_not_zero(&smc->sk.sk_refcnt) to pin the smc_sock. If the refcount has already reached zero (close path completed), it returns false and we bail out safely. Note: smc_hs_congested() has a similar lockless read of sk_user_data without rcu_read_lock(), but it only checks for NULL and accesses the global smc_hs_wq, never dereferencing any smc_sock field, so it is not affected. Reproducer was verified with mdelay injection and smc_run, the issue no longer occurs with this patch applied. [1] https://syzkaller.appspot.com/bug?extid=827ae2bfb3a3529333e9 Fixes: 8270d9c21041 ("net/smc: Limit backlog connections") Reported-by: syzbot+827ae2bfb3a3529333e9@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/67eaf9b8.050a0220.3c3d88.004a.GAE@google.com/T/ Suggested-by: Eric Dumazet Reviewed-by: Eric Dumazet Signed-off-by: Jiayuan Chen Link: https://patch.msgid.link/20260312092909.48325-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski --- net/smc/af_smc.c | 23 +++++++++++++++++------ net/smc/smc.h | 5 +++++ net/smc/smc_close.c | 2 +- 3 files changed, 23 insertions(+), 7 deletions(-) (limited to 'net') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index d0119afcc6a1..1a565095376a 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -131,7 +131,14 @@ static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk, struct smc_sock *smc; struct sock *child; - smc = smc_clcsock_user_data(sk); + rcu_read_lock(); + smc = smc_clcsock_user_data_rcu(sk); + if (!smc || !refcount_inc_not_zero(&smc->sk.sk_refcnt)) { + rcu_read_unlock(); + smc = NULL; + goto drop; + } + rcu_read_unlock(); if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) > sk->sk_max_ack_backlog) @@ -153,11 +160,14 @@ static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk, if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops) inet_csk(child)->icsk_af_ops = smc->ori_af_ops; } + sock_put(&smc->sk); return child; drop: dst_release(dst); tcp_listendrop(sk); + if (smc) + sock_put(&smc->sk); return NULL; } @@ -254,7 +264,7 @@ static void smc_fback_restore_callbacks(struct smc_sock *smc) struct sock *clcsk = smc->clcsock->sk; write_lock_bh(&clcsk->sk_callback_lock); - clcsk->sk_user_data = NULL; + rcu_assign_sk_user_data(clcsk, NULL); smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change); smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready); @@ -902,7 +912,7 @@ static void smc_fback_replace_callbacks(struct smc_sock *smc) struct sock *clcsk = smc->clcsock->sk; write_lock_bh(&clcsk->sk_callback_lock); - clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY); + __rcu_assign_sk_user_data_with_flags(clcsk, smc, SK_USER_DATA_NOCOPY); smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change, &smc->clcsk_state_change); @@ -2665,8 +2675,8 @@ int smc_listen(struct socket *sock, int backlog) * smc-specific sk_data_ready function */ write_lock_bh(&smc->clcsock->sk->sk_callback_lock); - smc->clcsock->sk->sk_user_data = - (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY); + __rcu_assign_sk_user_data_with_flags(smc->clcsock->sk, smc, + SK_USER_DATA_NOCOPY); smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready, smc_clcsock_data_ready, &smc->clcsk_data_ready); write_unlock_bh(&smc->clcsock->sk->sk_callback_lock); @@ -2687,10 +2697,11 @@ int smc_listen(struct socket *sock, int backlog) write_lock_bh(&smc->clcsock->sk->sk_callback_lock); smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready, &smc->clcsk_data_ready); - smc->clcsock->sk->sk_user_data = NULL; + rcu_assign_sk_user_data(smc->clcsock->sk, NULL); write_unlock_bh(&smc->clcsock->sk->sk_callback_lock); goto out; } + sock_set_flag(sk, SOCK_RCU_FREE); sk->sk_max_ack_backlog = backlog; sk->sk_ack_backlog = 0; sk->sk_state = SMC_LISTEN; diff --git a/net/smc/smc.h b/net/smc/smc.h index 9e6af72784ba..52145df83f6e 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -346,6 +346,11 @@ static inline struct smc_sock *smc_clcsock_user_data(const struct sock *clcsk) ((uintptr_t)clcsk->sk_user_data & ~SK_USER_DATA_NOCOPY); } +static inline struct smc_sock *smc_clcsock_user_data_rcu(const struct sock *clcsk) +{ + return (struct smc_sock *)rcu_dereference_sk_user_data(clcsk); +} + /* save target_cb in saved_cb, and replace target_cb with new_cb */ static inline void smc_clcsock_replace_cb(void (**target_cb)(struct sock *), void (*new_cb)(struct sock *), diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c index 10219f55aad1..bb0313ef5f7c 100644 --- a/net/smc/smc_close.c +++ b/net/smc/smc_close.c @@ -218,7 +218,7 @@ again: write_lock_bh(&smc->clcsock->sk->sk_callback_lock); smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready, &smc->clcsk_data_ready); - smc->clcsock->sk->sk_user_data = NULL; + rcu_assign_sk_user_data(smc->clcsock->sk, NULL); write_unlock_bh(&smc->clcsock->sk->sk_callback_lock); rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR); } -- cgit v1.2.3 From 66360460cab63c248ca5b1070a01c0c29133b960 Mon Sep 17 00:00:00 2001 From: Jamal Hadi Salim Date: Sun, 15 Mar 2026 11:54:22 -0400 Subject: net/sched: teql: Fix double-free in teql_master_xmit Whenever a TEQL devices has a lockless Qdisc as root, qdisc_reset should be called using the seq_lock to avoid racing with the datapath. Failure to do so may cause crashes like the following: [ 238.028993][ T318] BUG: KASAN: double-free in skb_release_data (net/core/skbuff.c:1139) [ 238.029328][ T318] Free of addr ffff88810c67ec00 by task poc_teql_uaf_ke/318 [ 238.029749][ T318] [ 238.029900][ T318] CPU: 3 UID: 0 PID: 318 Comm: poc_teql_ke Not tainted 7.0.0-rc3-00149-ge5b31d988a41 #704 PREEMPT(full) [ 238.029906][ T318] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 238.029910][ T318] Call Trace: [ 238.029913][ T318] [ 238.029916][ T318] dump_stack_lvl (lib/dump_stack.c:122) [ 238.029928][ T318] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) [ 238.029940][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029944][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) ... [ 238.029957][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029969][ T318] kasan_report_invalid_free (mm/kasan/report.c:221 mm/kasan/report.c:563) [ 238.029979][ T318] ? skb_release_data (net/core/skbuff.c:1139) [ 238.029989][ T318] check_slab_allocation (mm/kasan/common.c:231) [ 238.029995][ T318] kmem_cache_free (mm/slub.c:2637 (discriminator 1) mm/slub.c:6168 (discriminator 1) mm/slub.c:6298 (discriminator 1)) [ 238.030004][ T318] skb_release_data (net/core/skbuff.c:1139) ... [ 238.030025][ T318] sk_skb_reason_drop (net/core/skbuff.c:1256) [ 238.030032][ T318] pfifo_fast_reset (./include/linux/ptr_ring.h:171 ./include/linux/ptr_ring.h:309 ./include/linux/skb_array.h:98 net/sched/sch_generic.c:827) [ 238.030039][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) ... [ 238.030054][ T318] qdisc_reset (net/sched/sch_generic.c:1034) [ 238.030062][ T318] teql_destroy (./include/linux/spinlock.h:395 net/sched/sch_teql.c:157) [ 238.030071][ T318] __qdisc_destroy (./include/net/pkt_sched.h:328 net/sched/sch_generic.c:1077) [ 238.030077][ T318] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 238.030089][ T318] ? __pfx_qdisc_graft (net/sched/sch_api.c:1091) [ 238.030095][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030102][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030106][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 238.030114][ T318] tc_get_qdisc (net/sched/sch_api.c:1529 net/sched/sch_api.c:1556) ... [ 238.072958][ T318] Allocated by task 303 on cpu 5 at 238.026275s: [ 238.073392][ T318] kasan_save_stack (mm/kasan/common.c:58) [ 238.073884][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5)) [ 238.074230][ T318] __kasan_slab_alloc (mm/kasan/common.c:369) [ 238.074578][ T318] kmem_cache_alloc_node_noprof (./include/linux/kasan.h:253 mm/slub.c:4542 mm/slub.c:4869 mm/slub.c:4921) [ 238.076091][ T318] kmalloc_reserve (net/core/skbuff.c:616 (discriminator 107)) [ 238.076450][ T318] __alloc_skb (net/core/skbuff.c:713) [ 238.076834][ T318] alloc_skb_with_frags (./include/linux/skbuff.h:1383 net/core/skbuff.c:6763) [ 238.077178][ T318] sock_alloc_send_pskb (net/core/sock.c:2997) [ 238.077520][ T318] packet_sendmsg (net/packet/af_packet.c:2926 net/packet/af_packet.c:3019 net/packet/af_packet.c:3108) [ 238.081469][ T318] [ 238.081870][ T318] Freed by task 299 on cpu 1 at 238.028496s: [ 238.082761][ T318] kasan_save_stack (mm/kasan/common.c:58) [ 238.083481][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5)) [ 238.085348][ T318] kasan_save_free_info (mm/kasan/generic.c:587 (discriminator 1)) [ 238.085900][ T318] __kasan_slab_free (mm/kasan/common.c:287) [ 238.086439][ T318] kmem_cache_free (mm/slub.c:6168 (discriminator 3) mm/slub.c:6298 (discriminator 3)) [ 238.087007][ T318] skb_release_data (net/core/skbuff.c:1139) [ 238.087491][ T318] consume_skb (net/core/skbuff.c:1451) [ 238.087757][ T318] teql_master_xmit (net/sched/sch_teql.c:358) [ 238.088116][ T318] dev_hard_start_xmit (./include/linux/netdevice.h:5324 ./include/linux/netdevice.h:5333 net/core/dev.c:3871 net/core/dev.c:3887) [ 238.088468][ T318] sch_direct_xmit (net/sched/sch_generic.c:347) [ 238.088820][ T318] __qdisc_run (net/sched/sch_generic.c:420 (discriminator 1)) [ 238.089166][ T318] __dev_queue_xmit (./include/net/sch_generic.h:229 ./include/net/pkt_sched.h:121 ./include/net/pkt_sched.h:117 net/core/dev.c:4196 net/core/dev.c:4802) Workflow to reproduce: 1. Initialize a TEQL topology (dummy0 and ifb0 as slaves, teql0 up). 2. Start multiple sender workers continuously transmitting packets through teql0 to drive teql_master_xmit(). 3. In parallel, repeatedly delete and re-add the root qdisc on dummy0 and ifb0 via RTNETLINK, forcing frequent teardown and reset activity (teql_destroy() / qdisc_reset()). 4. After running both workloads concurrently for several iterations, KASAN reports slab-use-after-free or double-free in the skb free path. Fix this by moving dev_reset_queue to sch_generic.h and calling it, instead of qdisc_reset, in teql_destroy since it handles both the lock and lockless cases correctly for root qdiscs. Fixes: 96009c7d500e ("sched: replace __QDISC_STATE_RUNNING bit with a spin lock") Reported-by: Xianrui Dong Tested-by: Xianrui Dong Co-developed-by: Victor Nogueira Signed-off-by: Victor Nogueira Signed-off-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260315155422.147256-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski --- include/net/sch_generic.h | 28 ++++++++++++++++++++++++++++ net/sched/sch_generic.c | 27 --------------------------- net/sched/sch_teql.c | 7 ++----- 3 files changed, 30 insertions(+), 32 deletions(-) (limited to 'net') diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index d5d55cb21686..cafb266a0b80 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -716,6 +716,34 @@ void qdisc_destroy(struct Qdisc *qdisc); void qdisc_put(struct Qdisc *qdisc); void qdisc_put_unlocked(struct Qdisc *qdisc); void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, int n, int len); + +static inline void dev_reset_queue(struct net_device *dev, + struct netdev_queue *dev_queue, + void *_unused) +{ + struct Qdisc *qdisc; + bool nolock; + + qdisc = rtnl_dereference(dev_queue->qdisc_sleeping); + if (!qdisc) + return; + + nolock = qdisc->flags & TCQ_F_NOLOCK; + + if (nolock) + spin_lock_bh(&qdisc->seqlock); + spin_lock_bh(qdisc_lock(qdisc)); + + qdisc_reset(qdisc); + + spin_unlock_bh(qdisc_lock(qdisc)); + if (nolock) { + clear_bit(__QDISC_STATE_MISSED, &qdisc->state); + clear_bit(__QDISC_STATE_DRAINING, &qdisc->state); + spin_unlock_bh(&qdisc->seqlock); + } +} + #ifdef CONFIG_NET_SCHED int qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type, void *type_data); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 98ffe64de51f..9e726c3bd86b 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1288,33 +1288,6 @@ static void dev_deactivate_queue(struct net_device *dev, } } -static void dev_reset_queue(struct net_device *dev, - struct netdev_queue *dev_queue, - void *_unused) -{ - struct Qdisc *qdisc; - bool nolock; - - qdisc = rtnl_dereference(dev_queue->qdisc_sleeping); - if (!qdisc) - return; - - nolock = qdisc->flags & TCQ_F_NOLOCK; - - if (nolock) - spin_lock_bh(&qdisc->seqlock); - spin_lock_bh(qdisc_lock(qdisc)); - - qdisc_reset(qdisc); - - spin_unlock_bh(qdisc_lock(qdisc)); - if (nolock) { - clear_bit(__QDISC_STATE_MISSED, &qdisc->state); - clear_bit(__QDISC_STATE_DRAINING, &qdisc->state); - spin_unlock_bh(&qdisc->seqlock); - } -} - static bool some_qdisc_is_busy(struct net_device *dev) { unsigned int i; diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c index 783300d8b019..ec4039a201a2 100644 --- a/net/sched/sch_teql.c +++ b/net/sched/sch_teql.c @@ -146,15 +146,12 @@ teql_destroy(struct Qdisc *sch) master->slaves = NEXT_SLAVE(q); if (q == master->slaves) { struct netdev_queue *txq; - spinlock_t *root_lock; txq = netdev_get_tx_queue(master->dev, 0); master->slaves = NULL; - root_lock = qdisc_root_sleeping_lock(rtnl_dereference(txq->qdisc)); - spin_lock_bh(root_lock); - qdisc_reset(rtnl_dereference(txq->qdisc)); - spin_unlock_bh(root_lock); + dev_reset_queue(master->dev, + txq, NULL); } } skb_queue_purge(&dat->q); -- cgit v1.2.3 From a0671125d4f55e1e98d9bde8a0b671941987e208 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 13 Mar 2026 07:55:31 +0100 Subject: clsact: Fix use-after-free in init/destroy rollback asymmetry Fix a use-after-free in the clsact qdisc upon init/destroy rollback asymmetry. The latter is achieved by first fully initializing a clsact instance, and then in a second step having a replacement failure for the new clsact qdisc instance. clsact_init() initializes ingress first and then takes care of the egress part. This can fail midway, for example, via tcf_block_get_ext(). Upon failure, the kernel will trigger the clsact_destroy() callback. Commit 1cb6f0bae504 ("bpf: Fix too early release of tcx_entry") details the way how the transition is happening. If tcf_block_get_ext on the q->ingress_block ends up failing, we took the tcx_miniq_inc reference count on the ingress side, but not yet on the egress side. clsact_destroy() tests whether the {ingress,egress}_entry was non-NULL. However, even in midway failure on the replacement, both are in fact non-NULL with a valid egress_entry from the previous clsact instance. What we really need to test for is whether the qdisc instance-specific ingress or egress side previously got initialized. This adds a small helper for checking the miniq initialization called mini_qdisc_pair_inited, and utilizes that upon clsact_destroy() in order to fix the use-after-free scenario. Convert the ingress_destroy() side as well so both are consistent to each other. Fixes: 1cb6f0bae504 ("bpf: Fix too early release of tcx_entry") Reported-by: Keenan Dong Signed-off-by: Daniel Borkmann Cc: Martin KaFai Lau Acked-by: Martin KaFai Lau Link: https://patch.msgid.link/20260313065531.98639-1-daniel@iogearbox.net Signed-off-by: Paolo Abeni --- include/net/sch_generic.h | 5 +++++ net/sched/sch_ingress.c | 14 ++++++++------ 2 files changed, 13 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index cafb266a0b80..c3d657359a3d 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -1457,6 +1457,11 @@ void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc, void mini_qdisc_pair_block_init(struct mini_Qdisc_pair *miniqp, struct tcf_block *block); +static inline bool mini_qdisc_pair_inited(struct mini_Qdisc_pair *miniqp) +{ + return !!miniqp->p_miniq; +} + void mq_change_real_num_tx(struct Qdisc *sch, unsigned int new_real_tx); int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb)); diff --git a/net/sched/sch_ingress.c b/net/sched/sch_ingress.c index cc6051d4f2ef..c3e18bae8fbf 100644 --- a/net/sched/sch_ingress.c +++ b/net/sched/sch_ingress.c @@ -113,14 +113,15 @@ static void ingress_destroy(struct Qdisc *sch) { struct ingress_sched_data *q = qdisc_priv(sch); struct net_device *dev = qdisc_dev(sch); - struct bpf_mprog_entry *entry = rtnl_dereference(dev->tcx_ingress); + struct bpf_mprog_entry *entry; if (sch->parent != TC_H_INGRESS) return; tcf_block_put_ext(q->block, sch, &q->block_info); - if (entry) { + if (mini_qdisc_pair_inited(&q->miniqp)) { + entry = rtnl_dereference(dev->tcx_ingress); tcx_miniq_dec(entry); if (!tcx_entry_is_active(entry)) { tcx_entry_update(dev, NULL, true); @@ -290,10 +291,9 @@ static int clsact_init(struct Qdisc *sch, struct nlattr *opt, static void clsact_destroy(struct Qdisc *sch) { + struct bpf_mprog_entry *ingress_entry, *egress_entry; struct clsact_sched_data *q = qdisc_priv(sch); struct net_device *dev = qdisc_dev(sch); - struct bpf_mprog_entry *ingress_entry = rtnl_dereference(dev->tcx_ingress); - struct bpf_mprog_entry *egress_entry = rtnl_dereference(dev->tcx_egress); if (sch->parent != TC_H_CLSACT) return; @@ -301,7 +301,8 @@ static void clsact_destroy(struct Qdisc *sch) tcf_block_put_ext(q->ingress_block, sch, &q->ingress_block_info); tcf_block_put_ext(q->egress_block, sch, &q->egress_block_info); - if (ingress_entry) { + if (mini_qdisc_pair_inited(&q->miniqp_ingress)) { + ingress_entry = rtnl_dereference(dev->tcx_ingress); tcx_miniq_dec(ingress_entry); if (!tcx_entry_is_active(ingress_entry)) { tcx_entry_update(dev, NULL, true); @@ -309,7 +310,8 @@ static void clsact_destroy(struct Qdisc *sch) } } - if (egress_entry) { + if (mini_qdisc_pair_inited(&q->miniqp_egress)) { + egress_entry = rtnl_dereference(dev->tcx_egress); tcx_miniq_dec(egress_entry); if (!tcx_entry_is_active(egress_entry)) { tcx_entry_update(dev, NULL, false); -- cgit v1.2.3 From c73bb9a2d33bf81f6eecaa0f474b6c6dbe9855bd Mon Sep 17 00:00:00 2001 From: Xiang Mei Date: Tue, 17 Mar 2026 20:42:44 -0700 Subject: wifi: mac80211: fix NULL deref in mesh_matches_local() mesh_matches_local() unconditionally dereferences ie->mesh_config to compare mesh configuration parameters. When called from mesh_rx_csa_frame(), the parsed action-frame elements may not contain a Mesh Configuration IE, leaving ie->mesh_config NULL and triggering a kernel NULL pointer dereference. The other two callers are already safe: - ieee80211_mesh_rx_bcn_presp() checks !elems->mesh_config before calling mesh_matches_local() - mesh_plink_get_event() is only reached through mesh_process_plink_frame(), which checks !elems->mesh_config, too mesh_rx_csa_frame() is the only caller that passes raw parsed elements to mesh_matches_local() without guarding mesh_config. An adjacent attacker can exploit this by sending a crafted CSA action frame that includes a valid Mesh ID IE but omits the Mesh Configuration IE, crashing the kernel. The captured crash log: Oops: general protection fault, probably for non-canonical address ... KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Workqueue: events_unbound cfg80211_wiphy_work [...] Call Trace: ? __pfx_mesh_matches_local (net/mac80211/mesh.c:65) ieee80211_mesh_rx_queued_mgmt (net/mac80211/mesh.c:1686) [...] ieee80211_iface_work (net/mac80211/iface.c:1754 net/mac80211/iface.c:1802) [...] cfg80211_wiphy_work (net/wireless/core.c:426) process_one_work (net/kernel/workqueue.c:3280) ? assign_work (net/kernel/workqueue.c:1219) worker_thread (net/kernel/workqueue.c:3352) ? __pfx_worker_thread (net/kernel/workqueue.c:3385) kthread (net/kernel/kthread.c:436) [...] ret_from_fork_asm (net/arch/x86/entry/entry_64.S:255) This patch adds a NULL check for ie->mesh_config at the top of mesh_matches_local() to return false early when the Mesh Configuration IE is absent. Fixes: 2e3c8736820b ("mac80211: support functions for mesh") Reported-by: Weiming Shi Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260318034244.2595020-1-xmei5@asu.edu Signed-off-by: Johannes Berg --- net/mac80211/mesh.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net') diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index 28624e57aa49..8fdbdf9ba2a9 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -79,6 +79,9 @@ bool mesh_matches_local(struct ieee80211_sub_if_data *sdata, * - MDA enabled * - Power management control on fc */ + if (!ie->mesh_config) + return false; + if (!(ifmsh->mesh_id_len == ie->mesh_id_len && memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 && (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) && -- cgit v1.2.3 From d5ad6ab61cbd89afdb60881f6274f74328af3ee9 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 14 Mar 2026 06:54:55 +0000 Subject: wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure ieee80211_tx_prepare_skb() has three error paths, but only two of them free the skb. The first error path (ieee80211_tx_prepare() returning TX_DROP) does not free it, while invoke_tx_handlers() failure and the fragmentation check both do. Add kfree_skb() to the first error path so all three are consistent, and remove the now-redundant frees in callers (ath9k, mt76, mac80211_hwsim) to avoid double-free. Document the skb ownership guarantee in the function's kdoc. Signed-off-by: Felix Fietkau Link: https://patch.msgid.link/20260314065455.2462900-1-nbd@nbd.name Fixes: 06be6b149f7e ("mac80211: add ieee80211_tx_prepare_skb() helper function") Signed-off-by: Johannes Berg --- drivers/net/wireless/ath/ath9k/channel.c | 6 ++---- drivers/net/wireless/mediatek/mt76/scan.c | 4 +--- drivers/net/wireless/virtual/mac80211_hwsim.c | 1 - include/net/mac80211.h | 4 +++- net/mac80211/tx.c | 4 +++- 5 files changed, 9 insertions(+), 10 deletions(-) (limited to 'net') diff --git a/drivers/net/wireless/ath/ath9k/channel.c b/drivers/net/wireless/ath/ath9k/channel.c index 121e51ce1bc0..8b27d8cc086a 100644 --- a/drivers/net/wireless/ath/ath9k/channel.c +++ b/drivers/net/wireless/ath/ath9k/channel.c @@ -1006,7 +1006,7 @@ static void ath_scan_send_probe(struct ath_softc *sc, skb_set_queue_mapping(skb, IEEE80211_AC_VO); if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, NULL)) - goto error; + return; txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO]; if (ath_tx_start(sc->hw, skb, &txctl)) @@ -1119,10 +1119,8 @@ ath_chanctx_send_vif_ps_frame(struct ath_softc *sc, struct ath_vif *avp, skb->priority = 7; skb_set_queue_mapping(skb, IEEE80211_AC_VO); - if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, &sta)) { - dev_kfree_skb_any(skb); + if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, &sta)) return false; - } break; default: return false; diff --git a/drivers/net/wireless/mediatek/mt76/scan.c b/drivers/net/wireless/mediatek/mt76/scan.c index ff9176cdee3d..63b0447e55c1 100644 --- a/drivers/net/wireless/mediatek/mt76/scan.c +++ b/drivers/net/wireless/mediatek/mt76/scan.c @@ -63,10 +63,8 @@ mt76_scan_send_probe(struct mt76_dev *dev, struct cfg80211_ssid *ssid) rcu_read_lock(); - if (!ieee80211_tx_prepare_skb(phy->hw, vif, skb, band, NULL)) { - ieee80211_free_txskb(phy->hw, skb); + if (!ieee80211_tx_prepare_skb(phy->hw, vif, skb, band, NULL)) goto out; - } info = IEEE80211_SKB_CB(skb); if (req->no_cck) diff --git a/drivers/net/wireless/virtual/mac80211_hwsim.c b/drivers/net/wireless/virtual/mac80211_hwsim.c index f6b890dea7e0..1b6e55eb81a2 100644 --- a/drivers/net/wireless/virtual/mac80211_hwsim.c +++ b/drivers/net/wireless/virtual/mac80211_hwsim.c @@ -3021,7 +3021,6 @@ static void hw_scan_work(struct work_struct *work) hwsim->tmp_chan->band, NULL)) { rcu_read_unlock(); - kfree_skb(probe); continue; } diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 7f9d96939a4e..adce2144a678 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -7407,7 +7407,9 @@ void ieee80211_report_wowlan_wakeup(struct ieee80211_vif *vif, * @band: the band to transmit on * @sta: optional pointer to get the station to send the frame to * - * Return: %true if the skb was prepared, %false otherwise + * Return: %true if the skb was prepared, %false otherwise. + * On failure, the skb is freed by this function; callers must not + * free it again. * * Note: must be called under RCU lock */ diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 8cdbd417d7be..b7aedaab8483 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1899,8 +1899,10 @@ bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw, struct ieee80211_tx_data tx; struct sk_buff *skb2; - if (ieee80211_tx_prepare(sdata, &tx, NULL, skb) == TX_DROP) + if (ieee80211_tx_prepare(sdata, &tx, NULL, skb) == TX_DROP) { + kfree_skb(skb); return false; + } info->band = band; info->control.vif = vif; -- cgit v1.2.3 From 06413793526251870e20402c39930804f14d59c0 Mon Sep 17 00:00:00 2001 From: Minhong He Date: Mon, 16 Mar 2026 15:33:01 +0800 Subject: ipv6: add NULL checks for idev in SRv6 paths __in6_dev_get() can return NULL when the device has no IPv6 configuration (e.g. MTU < IPV6_MIN_MTU or after NETDEV_UNREGISTER). Add NULL checks for idev returned by __in6_dev_get() in both seg6_hmac_validate_skb() and ipv6_srh_rcv() to prevent potential NULL pointer dereferences. Fixes: 1ababeba4a21 ("ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header)") Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support") Signed-off-by: Minhong He Reviewed-by: Andrea Mayer Link: https://patch.msgid.link/20260316073301.106643-1-heminhong@kylinos.cn Signed-off-by: Jakub Kicinski --- net/ipv6/exthdrs.c | 4 ++++ net/ipv6/seg6_hmac.c | 2 ++ 2 files changed, 6 insertions(+) (limited to 'net') diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index 5e3610a926cf..95558fd6f447 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -379,6 +379,10 @@ static int ipv6_srh_rcv(struct sk_buff *skb) hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); idev = __in6_dev_get(skb->dev); + if (!idev) { + kfree_skb(skb); + return -1; + } accept_seg6 = min(READ_ONCE(net->ipv6.devconf_all->seg6_enabled), READ_ONCE(idev->cnf.seg6_enabled)); diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c index ee6bac0160ac..e6964c6b0d38 100644 --- a/net/ipv6/seg6_hmac.c +++ b/net/ipv6/seg6_hmac.c @@ -184,6 +184,8 @@ bool seg6_hmac_validate_skb(struct sk_buff *skb) int require_hmac; idev = __in6_dev_get(skb->dev); + if (!idev) + return false; srh = (struct ipv6_sr_hdr *)skb_transport_header(skb); -- cgit v1.2.3 From 24f90fa3994b992d1a09003a3db2599330a5232a Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 17 Mar 2026 12:23:08 +0100 Subject: netfilter: bpf: defer hook memory release until rcu readers are done Yiming Qian reports UaF when concurrent process is dumping hooks via nfnetlink_hooks: BUG: KASAN: slab-use-after-free in nfnl_hook_dump_one.isra.0+0xe71/0x10f0 Read of size 8 at addr ffff888003edbf88 by task poc/79 Call Trace: nfnl_hook_dump_one.isra.0+0xe71/0x10f0 netlink_dump+0x554/0x12b0 nfnl_hook_get+0x176/0x230 [..] Defer release until after concurrent readers have completed. Reported-by: Yiming Qian Fixes: 84601d6ee68a ("bpf: add bpf_link support for BPF_NETFILTER programs") Signed-off-by: Florian Westphal --- net/netfilter/nf_bpf_link.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/netfilter/nf_bpf_link.c b/net/netfilter/nf_bpf_link.c index 6f3a6411f4af..c20031891b86 100644 --- a/net/netfilter/nf_bpf_link.c +++ b/net/netfilter/nf_bpf_link.c @@ -170,7 +170,7 @@ static int bpf_nf_link_update(struct bpf_link *link, struct bpf_prog *new_prog, static const struct bpf_link_ops bpf_nf_link_lops = { .release = bpf_nf_link_release, - .dealloc = bpf_nf_link_dealloc, + .dealloc_deferred = bpf_nf_link_dealloc, .detach = bpf_nf_link_detach, .show_fdinfo = bpf_nf_link_show_info, .fill_link_info = bpf_nf_link_fill_link_info, -- cgit v1.2.3 From d73f4b53aaaea4c95f245e491aa5eeb8a21874ce Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 17 Mar 2026 20:00:26 +0100 Subject: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtable can be already registered, exposing this flowtable to packet path and nfnetlink_hook control plane. This error path is rare, it should only happen by reaching the maximum number hooks or by failing to set up to hardware offload, just call synchronize_rcu(). There is a check for already used device hooks by different flowtable that could result in EEXIST at this late stage. The hook parser can be updated to perform this check earlier to this error path really becomes rarely exercised. Uncovered by KASAN reported as use-after-free from nfnetlink_hook path when dumping hooks. Fixes: 3b49e2e94e6e ("netfilter: nf_tables: add flow table netlink frontend") Reported-by: Yiming Qian Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 9b1c8d0a35fb..3922cff1bb3d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -9203,6 +9203,7 @@ static int nf_tables_newflowtable(struct sk_buff *skb, return 0; err_flowtable_hooks: + synchronize_rcu(); nft_trans_destroy(trans); err_flowtable_trans: nft_hooks_destroy(&flowtable->hook_list); -- cgit v1.2.3 From dbdfaae9609629a9569362e3b8f33d0a20fd783c Mon Sep 17 00:00:00 2001 From: Weiming Shi Date: Thu, 19 Mar 2026 15:32:44 +0800 Subject: nfnetlink_osf: validate individual option lengths in fingerprints nfnl_osf_add_callback() validates opt_num bounds and string NUL-termination but does not check individual option length fields. A zero-length option causes nf_osf_match_one() to enter the option matching loop even when foptsize sums to zero, which matches packets with no TCP options where ctx->optp is NULL: Oops: general protection fault KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: nf_osf_match (net/netfilter/nfnetlink_osf.c:227) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:293) nf_hook_slow (net/netfilter/core.c:623) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) Additionally, an MSS option (kind=2) with length < 4 causes out-of-bounds reads when nf_osf_match_one() unconditionally accesses optp[2] and optp[3] for MSS value extraction. While RFC 9293 section 3.2 specifies that the MSS option is always exactly 4 bytes (Kind=2, Length=4), the check uses "< 4" rather than "!= 4" because lengths greater than 4 do not cause memory safety issues -- the buffer is guaranteed to be at least foptsize bytes by the ctx->optsize == foptsize check. Reject fingerprints where any option has zero length, or where an MSS option has length less than 4, at add time rather than trusting these values in the packet matching hot path. Fixes: 11eeef41d5f6 ("netfilter: passive OS fingerprint xtables match") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Signed-off-by: Florian Westphal --- net/netfilter/nfnetlink_osf.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'net') diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c index 94e3eac5743a..45d9ad231a92 100644 --- a/net/netfilter/nfnetlink_osf.c +++ b/net/netfilter/nfnetlink_osf.c @@ -302,7 +302,9 @@ static int nfnl_osf_add_callback(struct sk_buff *skb, { struct nf_osf_user_finger *f; struct nf_osf_finger *kf = NULL, *sf; + unsigned int tot_opt_len = 0; int err = 0; + int i; if (!capable(CAP_NET_ADMIN)) return -EPERM; @@ -318,6 +320,17 @@ static int nfnl_osf_add_callback(struct sk_buff *skb, if (f->opt_num > ARRAY_SIZE(f->opt)) return -EINVAL; + for (i = 0; i < f->opt_num; i++) { + if (!f->opt[i].length || f->opt[i].length > MAX_IPOPTLEN) + return -EINVAL; + if (f->opt[i].kind == OSFOPT_MSS && f->opt[i].length < 4) + return -EINVAL; + + tot_opt_len += f->opt[i].length; + if (tot_opt_len > MAX_IPOPTLEN) + return -EINVAL; + } + if (!memchr(f->genre, 0, MAXGENRELEN) || !memchr(f->subtype, 0, MAXGENRELEN) || !memchr(f->version, 0, MAXGENRELEN)) -- cgit v1.2.3 From 0f9ea7141f365b4f27226898e62220fb98ef8dc6 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 17 Mar 2026 09:10:13 -0700 Subject: net: shaper: protect late read accesses to the hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run. Fixes: 4b623f9f0f59 ("net-shapers: implement NL get operation") Reported-by: Paul Moses Link: https://lore.kernel.org/20260309173450.538026-1-p@1g4.org Signed-off-by: Jakub Kicinski Link: https://patch.msgid.link/20260317161014.779569-1-kuba@kernel.org Signed-off-by: Paolo Abeni --- net/shaper/shaper.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/shaper/shaper.c b/net/shaper/shaper.c index 3fd6629cb999..6b4c87e12f1f 100644 --- a/net/shaper/shaper.c +++ b/net/shaper/shaper.c @@ -65,6 +65,21 @@ net_shaper_hierarchy(struct net_shaper_binding *binding) return NULL; } +static struct net_shaper_hierarchy * +net_shaper_hierarchy_rcu(struct net_shaper_binding *binding) +{ + /* Readers look up the device and take a ref, then take RCU lock + * later at which point netdev may have been unregistered and flushed. + * READ_ONCE() pairs with WRITE_ONCE() in net_shaper_hierarchy_setup. + */ + if (binding->type == NET_SHAPER_BINDING_TYPE_NETDEV && + READ_ONCE(binding->netdev->reg_state) <= NETREG_REGISTERED) + return READ_ONCE(binding->netdev->net_shaper_hierarchy); + + /* No other type supported yet. */ + return NULL; +} + static const struct net_shaper_ops * net_shaper_ops(struct net_shaper_binding *binding) { @@ -251,9 +266,10 @@ static struct net_shaper * net_shaper_lookup(struct net_shaper_binding *binding, const struct net_shaper_handle *handle) { - struct net_shaper_hierarchy *hierarchy = net_shaper_hierarchy(binding); u32 index = net_shaper_handle_to_index(handle); + struct net_shaper_hierarchy *hierarchy; + hierarchy = net_shaper_hierarchy_rcu(binding); if (!hierarchy || xa_get_mark(&hierarchy->shapers, index, NET_SHAPER_NOT_VALID)) return NULL; @@ -778,17 +794,19 @@ int net_shaper_nl_get_dumpit(struct sk_buff *skb, /* Don't error out dumps performed before any set operation. */ binding = net_shaper_binding_from_ctx(ctx); - hierarchy = net_shaper_hierarchy(binding); - if (!hierarchy) - return 0; rcu_read_lock(); + hierarchy = net_shaper_hierarchy_rcu(binding); + if (!hierarchy) + goto out_unlock; + for (; (shaper = xa_find(&hierarchy->shapers, &ctx->start_index, U32_MAX, XA_PRESENT)); ctx->start_index++) { ret = net_shaper_fill_one(skb, binding, shaper, info); if (ret) break; } +out_unlock: rcu_read_unlock(); return ret; -- cgit v1.2.3 From d75ec7e8ba1979a1eb0b9211d94d749cdce849c8 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 17 Mar 2026 09:10:14 -0700 Subject: net: shaper: protect from late creation of hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak. Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy. We may take the lock for devices which don't support shapers but we're only dealing with SET operations here, not taking the lock would be optimizing for an error case. Fixes: 93954b40f6a4 ("net-shapers: implement NL set and delete operations") Link: https://lore.kernel.org/20260309173450.538026-1-p@1g4.org Signed-off-by: Jakub Kicinski Link: https://patch.msgid.link/20260317161014.779569-2-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/netlink/specs/net_shaper.yaml | 12 +-- net/shaper/shaper.c | 134 +++++++++++++++------------- net/shaper/shaper_nl_gen.c | 12 +-- net/shaper/shaper_nl_gen.h | 5 ++ 4 files changed, 89 insertions(+), 74 deletions(-) (limited to 'net') diff --git a/Documentation/netlink/specs/net_shaper.yaml b/Documentation/netlink/specs/net_shaper.yaml index 0b1b54be48f9..3f2ad772b64b 100644 --- a/Documentation/netlink/specs/net_shaper.yaml +++ b/Documentation/netlink/specs/net_shaper.yaml @@ -247,8 +247,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: - ifindex @@ -278,8 +278,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: *ns-binding @@ -309,8 +309,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: - ifindex diff --git a/net/shaper/shaper.c b/net/shaper/shaper.c index 6b4c87e12f1f..94bc9c7382ea 100644 --- a/net/shaper/shaper.c +++ b/net/shaper/shaper.c @@ -36,24 +36,6 @@ static struct net_shaper_binding *net_shaper_binding_from_ctx(void *ctx) return &((struct net_shaper_nl_ctx *)ctx)->binding; } -static void net_shaper_lock(struct net_shaper_binding *binding) -{ - switch (binding->type) { - case NET_SHAPER_BINDING_TYPE_NETDEV: - netdev_lock(binding->netdev); - break; - } -} - -static void net_shaper_unlock(struct net_shaper_binding *binding) -{ - switch (binding->type) { - case NET_SHAPER_BINDING_TYPE_NETDEV: - netdev_unlock(binding->netdev); - break; - } -} - static struct net_shaper_hierarchy * net_shaper_hierarchy(struct net_shaper_binding *binding) { @@ -219,12 +201,49 @@ static int net_shaper_ctx_setup(const struct genl_info *info, int type, return 0; } +/* Like net_shaper_ctx_setup(), but for "write" handlers (never for dumps!) + * Acquires the lock protecting the hierarchy (instance lock for netdev). + */ +static int net_shaper_ctx_setup_lock(const struct genl_info *info, int type, + struct net_shaper_nl_ctx *ctx) +{ + struct net *ns = genl_info_net(info); + struct net_device *dev; + int ifindex; + + if (GENL_REQ_ATTR_CHECK(info, type)) + return -EINVAL; + + ifindex = nla_get_u32(info->attrs[type]); + dev = netdev_get_by_index_lock(ns, ifindex); + if (!dev) { + NL_SET_BAD_ATTR(info->extack, info->attrs[type]); + return -ENOENT; + } + + if (!dev->netdev_ops->net_shaper_ops) { + NL_SET_BAD_ATTR(info->extack, info->attrs[type]); + netdev_unlock(dev); + return -EOPNOTSUPP; + } + + ctx->binding.type = NET_SHAPER_BINDING_TYPE_NETDEV; + ctx->binding.netdev = dev; + return 0; +} + static void net_shaper_ctx_cleanup(struct net_shaper_nl_ctx *ctx) { if (ctx->binding.type == NET_SHAPER_BINDING_TYPE_NETDEV) netdev_put(ctx->binding.netdev, &ctx->dev_tracker); } +static void net_shaper_ctx_cleanup_unlock(struct net_shaper_nl_ctx *ctx) +{ + if (ctx->binding.type == NET_SHAPER_BINDING_TYPE_NETDEV) + netdev_unlock(ctx->binding.netdev); +} + static u32 net_shaper_handle_to_index(const struct net_shaper_handle *handle) { return FIELD_PREP(NET_SHAPER_SCOPE_MASK, handle->scope) | @@ -278,7 +297,7 @@ net_shaper_lookup(struct net_shaper_binding *binding, } /* Allocate on demand the per device shaper's hierarchy container. - * Called under the net shaper lock + * Called under the lock protecting the hierarchy (instance lock for netdev) */ static struct net_shaper_hierarchy * net_shaper_hierarchy_setup(struct net_shaper_binding *binding) @@ -697,6 +716,22 @@ void net_shaper_nl_post_doit(const struct genl_split_ops *ops, net_shaper_generic_post(info); } +int net_shaper_nl_pre_doit_write(const struct genl_split_ops *ops, + struct sk_buff *skb, struct genl_info *info) +{ + struct net_shaper_nl_ctx *ctx = (struct net_shaper_nl_ctx *)info->ctx; + + BUILD_BUG_ON(sizeof(*ctx) > sizeof(info->ctx)); + + return net_shaper_ctx_setup_lock(info, NET_SHAPER_A_IFINDEX, ctx); +} + +void net_shaper_nl_post_doit_write(const struct genl_split_ops *ops, + struct sk_buff *skb, struct genl_info *info) +{ + net_shaper_ctx_cleanup_unlock((struct net_shaper_nl_ctx *)info->ctx); +} + int net_shaper_nl_pre_dumpit(struct netlink_callback *cb) { struct net_shaper_nl_ctx *ctx = (struct net_shaper_nl_ctx *)cb->ctx; @@ -824,45 +859,38 @@ int net_shaper_nl_set_doit(struct sk_buff *skb, struct genl_info *info) binding = net_shaper_binding_from_ctx(info->ctx); - net_shaper_lock(binding); ret = net_shaper_parse_info(binding, info->attrs, info, &shaper, &exists); if (ret) - goto unlock; + return ret; if (!exists) net_shaper_default_parent(&shaper.handle, &shaper.parent); hierarchy = net_shaper_hierarchy_setup(binding); - if (!hierarchy) { - ret = -ENOMEM; - goto unlock; - } + if (!hierarchy) + return -ENOMEM; /* The 'set' operation can't create node-scope shapers. */ handle = shaper.handle; if (handle.scope == NET_SHAPER_SCOPE_NODE && - !net_shaper_lookup(binding, &handle)) { - ret = -ENOENT; - goto unlock; - } + !net_shaper_lookup(binding, &handle)) + return -ENOENT; ret = net_shaper_pre_insert(binding, &handle, info->extack); if (ret) - goto unlock; + return ret; ops = net_shaper_ops(binding); ret = ops->set(binding, &shaper, info->extack); if (ret) { net_shaper_rollback(binding); - goto unlock; + return ret; } net_shaper_commit(binding, 1, &shaper); -unlock: - net_shaper_unlock(binding); - return ret; + return 0; } static int __net_shaper_delete(struct net_shaper_binding *binding, @@ -1090,35 +1118,26 @@ int net_shaper_nl_delete_doit(struct sk_buff *skb, struct genl_info *info) binding = net_shaper_binding_from_ctx(info->ctx); - net_shaper_lock(binding); ret = net_shaper_parse_handle(info->attrs[NET_SHAPER_A_HANDLE], info, &handle); if (ret) - goto unlock; + return ret; hierarchy = net_shaper_hierarchy(binding); - if (!hierarchy) { - ret = -ENOENT; - goto unlock; - } + if (!hierarchy) + return -ENOENT; shaper = net_shaper_lookup(binding, &handle); - if (!shaper) { - ret = -ENOENT; - goto unlock; - } + if (!shaper) + return -ENOENT; if (handle.scope == NET_SHAPER_SCOPE_NODE) { ret = net_shaper_pre_del_node(binding, shaper, info->extack); if (ret) - goto unlock; + return ret; } - ret = __net_shaper_delete(binding, shaper, info->extack); - -unlock: - net_shaper_unlock(binding); - return ret; + return __net_shaper_delete(binding, shaper, info->extack); } static int net_shaper_group_send_reply(struct net_shaper_binding *binding, @@ -1167,21 +1186,17 @@ int net_shaper_nl_group_doit(struct sk_buff *skb, struct genl_info *info) if (!net_shaper_ops(binding)->group) return -EOPNOTSUPP; - net_shaper_lock(binding); leaves_count = net_shaper_list_len(info, NET_SHAPER_A_LEAVES); if (!leaves_count) { NL_SET_BAD_ATTR(info->extack, info->attrs[NET_SHAPER_A_LEAVES]); - ret = -EINVAL; - goto unlock; + return -EINVAL; } leaves = kcalloc(leaves_count, sizeof(struct net_shaper) + sizeof(struct net_shaper *), GFP_KERNEL); - if (!leaves) { - ret = -ENOMEM; - goto unlock; - } + if (!leaves) + return -ENOMEM; old_nodes = (void *)&leaves[leaves_count]; ret = net_shaper_parse_node(binding, info->attrs, info, &node); @@ -1258,9 +1273,6 @@ int net_shaper_nl_group_doit(struct sk_buff *skb, struct genl_info *info) free_leaves: kfree(leaves); - -unlock: - net_shaper_unlock(binding); return ret; free_msg: @@ -1370,14 +1382,12 @@ static void net_shaper_flush(struct net_shaper_binding *binding) if (!hierarchy) return; - net_shaper_lock(binding); xa_lock(&hierarchy->shapers); xa_for_each(&hierarchy->shapers, index, cur) { __xa_erase(&hierarchy->shapers, index); kfree(cur); } xa_unlock(&hierarchy->shapers); - net_shaper_unlock(binding); kfree(hierarchy); } diff --git a/net/shaper/shaper_nl_gen.c b/net/shaper/shaper_nl_gen.c index e8cccc4c1180..9b29be3ef19a 100644 --- a/net/shaper/shaper_nl_gen.c +++ b/net/shaper/shaper_nl_gen.c @@ -99,27 +99,27 @@ static const struct genl_split_ops net_shaper_nl_ops[] = { }, { .cmd = NET_SHAPER_CMD_SET, - .pre_doit = net_shaper_nl_pre_doit, + .pre_doit = net_shaper_nl_pre_doit_write, .doit = net_shaper_nl_set_doit, - .post_doit = net_shaper_nl_post_doit, + .post_doit = net_shaper_nl_post_doit_write, .policy = net_shaper_set_nl_policy, .maxattr = NET_SHAPER_A_IFINDEX, .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, }, { .cmd = NET_SHAPER_CMD_DELETE, - .pre_doit = net_shaper_nl_pre_doit, + .pre_doit = net_shaper_nl_pre_doit_write, .doit = net_shaper_nl_delete_doit, - .post_doit = net_shaper_nl_post_doit, + .post_doit = net_shaper_nl_post_doit_write, .policy = net_shaper_delete_nl_policy, .maxattr = NET_SHAPER_A_IFINDEX, .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, }, { .cmd = NET_SHAPER_CMD_GROUP, - .pre_doit = net_shaper_nl_pre_doit, + .pre_doit = net_shaper_nl_pre_doit_write, .doit = net_shaper_nl_group_doit, - .post_doit = net_shaper_nl_post_doit, + .post_doit = net_shaper_nl_post_doit_write, .policy = net_shaper_group_nl_policy, .maxattr = NET_SHAPER_A_LEAVES, .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, diff --git a/net/shaper/shaper_nl_gen.h b/net/shaper/shaper_nl_gen.h index ec41c90431a4..42c46c52c775 100644 --- a/net/shaper/shaper_nl_gen.h +++ b/net/shaper/shaper_nl_gen.h @@ -18,12 +18,17 @@ extern const struct nla_policy net_shaper_leaf_info_nl_policy[NET_SHAPER_A_WEIGH int net_shaper_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, struct genl_info *info); +int net_shaper_nl_pre_doit_write(const struct genl_split_ops *ops, + struct sk_buff *skb, struct genl_info *info); int net_shaper_nl_cap_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, struct genl_info *info); void net_shaper_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb, struct genl_info *info); void +net_shaper_nl_post_doit_write(const struct genl_split_ops *ops, + struct sk_buff *skb, struct genl_info *info); +void net_shaper_nl_cap_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb, struct genl_info *info); int net_shaper_nl_pre_dumpit(struct netlink_callback *cb); -- cgit v1.2.3 From 614aefe56af8e13331e50220c936fc0689cf5675 Mon Sep 17 00:00:00 2001 From: Weiming Shi Date: Wed, 18 Mar 2026 21:06:01 +0800 Subject: icmp: fix NULL pointer dereference in icmp_tag_validation() icmp_tag_validation() unconditionally dereferences the result of rcu_dereference(inet_protos[proto]) without checking for NULL. The inet_protos[] array is sparse -- only about 15 of 256 protocol numbers have registered handlers. When ip_no_pmtu_disc is set to 3 (hardened PMTU mode) and the kernel receives an ICMP Fragmentation Needed error with a quoted inner IP header containing an unregistered protocol number, the NULL dereference causes a kernel panic in softirq context. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:icmp_unreach (net/ipv4/icmp.c:1085 net/ipv4/icmp.c:1143) Call Trace: icmp_rcv (net/ipv4/icmp.c:1527) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207) ip_local_deliver_finish (net/ipv4/ip_input.c:242) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) __netif_receive_skb_one_core (net/core/dev.c:6164) process_backlog (net/core/dev.c:6628) handle_softirqs (kernel/softirq.c:561) Add a NULL check before accessing icmp_strict_tag_validation. If the protocol has no registered handler, return false since it cannot perform strict tag validation. Fixes: 8ed1dc44d3e9 ("ipv4: introduce hardened ip_no_pmtu_disc mode") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Link: https://patch.msgid.link/20260318130558.1050247-4-bestswngs@gmail.com Signed-off-by: Jakub Kicinski --- net/ipv4/icmp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index a62b4c4033cc..568bd1e95d44 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -1079,10 +1079,12 @@ out: static bool icmp_tag_validation(int proto) { + const struct net_protocol *ipprot; bool ok; rcu_read_lock(); - ok = rcu_dereference(inet_protos[proto])->icmp_strict_tag_validation; + ipprot = rcu_dereference(inet_protos[proto]); + ok = ipprot ? ipprot->icmp_strict_tag_validation : false; rcu_read_unlock(); return ok; } -- cgit v1.2.3 From 7ab4a7c5d969642782b8a5b608da0dd02aa9f229 Mon Sep 17 00:00:00 2001 From: Li Xiasong Date: Thu, 19 Mar 2026 19:21:59 +0800 Subject: MPTCP: fix lock class name family in pm_nl_create_listen_socket In mptcp_pm_nl_create_listen_socket(), use entry->addr.family instead of sk->sk_family for lock class setup. The 'sk' parameter is a netlink socket, not the MPTCP subflow socket being created. Fixes: cee4034a3db1 ("mptcp: fix lockdep false positive in mptcp_pm_nl_create_listen_socket()") Signed-off-by: Li Xiasong Reviewed-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260319112159.3118874-1-lixiasong1@huawei.com Signed-off-by: Jakub Kicinski --- net/mptcp/pm_kernel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c index b2b9df43960e..82e59f9c6dd9 100644 --- a/net/mptcp/pm_kernel.c +++ b/net/mptcp/pm_kernel.c @@ -838,7 +838,7 @@ static struct lock_class_key mptcp_keys[2]; static int mptcp_pm_nl_create_listen_socket(struct sock *sk, struct mptcp_pm_addr_entry *entry) { - bool is_ipv6 = sk->sk_family == AF_INET6; + bool is_ipv6 = entry->addr.family == AF_INET6; int addrlen = sizeof(struct sockaddr_in); struct sockaddr_storage addr; struct sock *newsk, *ssk; -- cgit v1.2.3