summaryrefslogtreecommitdiff
path: root/net
AgeCommit message (Collapse)AuthorFilesLines
7 daysinet: frags: strip GSO state from fragments before reassemblyXinyang Ge1-0/+7
commit d5dc1e69fd7258ea605c9952e5d5947539159ae3 upstream. A virtio_net_hdr (tun/tap, or AF_PACKET with PACKET_VNET_HDR) can mark an IPv4 or IPv6 fragment as GSO; nothing relates gso_type to frag_off. inet_frag_reasm_prepare()/inet_frag_reasm_finish() keep the first fragment's skb as the head of the reassembled datagram, including its shinfo->gso_size/gso_type/gso_segs, and chain the remaining fragments on frag_list with whatever linear/paged layout they arrived with. After ip_defrag() (ip_local_deliver(), nf_defrag_ipv4, ...) the reassembled skb therefore still claims to be GSO (SKB_GSO_DODGY), and the next software segmentation point - udp_rcv_segment() on local delivery, validate_xmit_skb(), or the ip_finish_output_gso() slow path - hands it to skb_segment(). skb_segment()'s frag_list walk assumes GRO-shaped input and hits one of its BUG_ON()s. Two writes to a tap by an unprivileged user in its own userns are enough: kernel BUG at net/core/skbuff.c:4899! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 1000 PID: 82 Comm: poc Not tainted 7.2.0-pentest+ #2 RIP: 0010:skb_segment+0x20ca/0x48b0 Call Trace: <TASK> __udp_gso_segment+0x29a/0x27d0 udp4_ufo_fragment+0x458/0x6c0 inet_gso_segment+0x429/0x1340 skb_mac_gso_segment+0x233/0x4f0 __skb_gso_segment+0x308/0x660 udp_queue_rcv_skb+0x440/0xad0 udp_unicast_rcv_skb+0xc7/0x2c0 udp_rcv+0x16ce/0x2260 ip_protocol_deliver_rcu+0x197/0x2d0 ip_local_deliver+0x430/0x690 ip_rcv+0x16f/0x1f0 __netif_receive_skb_one_core+0x15e/0x1c0 __netif_receive_skb+0x1e/0x110 netif_receive_skb+0xf6/0x5c0 tun_rx_batched.isra.0+0x3ab/0x790 tun_get_user+0x17c3/0x3550 tun_chr_write_iter+0xba/0x1b0 vfs_write+0x646/0x1130 </TASK> Kernel panic - not syncing: Fatal exception in interrupt This runs with BH disabled, so it is a panic rather than an oops. The same is reachable with CAP_NET_RAW in a netns where a defrag point precedes a GSO point, and from a guest whose VMM forwards virtio_net_hdr to a tap. The SKB_GSO_DODGY frag_list checks added by commit 3dcbdb134f32 ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list") and by commit 9e4b7a99a03a ("net: gso: fix panic on frag_list with mixed head alloc types") do not cover it: page-backed heads skip them, and kmalloc heads skip them when gso_size == skb_headlen(head), which the sender controls. An skb entering a frag queue is an IP fragment by definition and cannot legitimately carry GSO state: GRO does not merge fragments and the stack segments before it fragments, so only untrusted sources are affected. This has been reachable since commit f43798c27684 ("tun: Allow GSO using virtio_net_hdr"), the first path that let userspace attach GSO metadata to an IP fragment. Reset the GSO fields of every fragment as it is queued, in inet_frag_queue_insert(), which IPv4, IPv6, nf_conntrack_reasm and 6lowpan reassembly share; then neither the head nor the frag_list members of the reassembled skb carry them (the members matter too: the ip_do_fragment()/ip6_fragment() fast paths send them out as they are). The head may remain CHECKSUM_PARTIAL; that is already accepted on receive and resolved by skb_checksum_help() in ip_do_fragment()/ip6_fragment() on forward. Tested on top of net.git (dc4b95b8fee9), x86_64: the tap reproducer above, two further IPv4 frag_list geometries that reach BUG_ON(i >= nfrags) and BUG_ON(!list_skb->head_frag), and an IPv6 fragment-header variant (udp6_ufo_fragment()) each panic the unpatched kernel; with this patch all four datagrams are delivered intact and nothing is logged. Fixes: f43798c27684 ("tun: Allow GSO using virtio_net_hdr") Cc: stable@kernel.org Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Xinyang Ge <xinyang@anthropic.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/937926e509f2acd8e0e66520dc2b30fd6b4d1687.1787839506.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255Ali Ahmet Memis1-0/+8
commit 5d95286b6d6e8f1d304da7522bfa6860fc017e48 upstream. mgmt_hci_cmd_sync() checks that the message length agrees with params_len but puts no upper bound on it. params_len is __le16 while the parameter length in the HCI command header is a u8: struct hci_command_hdr { __le16 opcode; __u8 plen; } __packed; hci_cmd_sync_alloc() assigns one to the other: hdr->plen = plen; if (plen) skb_put_data(skb, param, plen); so a params_len of 256 leaves plen at 0 while all 256 bytes are still appended. The frame handed to the driver then declares no parameters and carries 256 of them. On a length framed transport such as H:4 the controller takes the trailing bytes as the start of the next packet. The mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about 1KB this way. Commit 03f1700b9b4d ("Bluetooth: MGMT: reject malformed HCI_CMD_SYNC commands") only made params_len agree with the message length, a value that fits the message but not the header field is still accepted. Reject params_len that does not fit the header field. Fixes: 827af4787e74 ("Bluetooth: MGMT: Add initial implementation of MGMT_OP_HCI_CMD_SYNC") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: ISO: zero the sockaddr before returning it in getnameAli Ahmet Memis1-0/+2
commit 884cf2cc957da7ac178a0e6c6c69ddfec0481cc8 upstream. iso_sock_getname() fills a struct sockaddr_iso in place and returns its size without clearing it first, so bytes it does not write are copied to user space from the kernel stack. The getsockname(2) and getpeername(2) paths both run through do_getsockname(), which hands getname() an uninitialized sockaddr_storage on the stack and copies back up to the number of bytes getname() returns, so the driver has to initialize every byte it accounts for. Two ranges are left uninitialized: - struct sockaddr_iso is 10 bytes but only 9 are written (family, iso_bdaddr, iso_bdaddr_type), leaking the trailing pad byte on every call. - for a broadcast peer (BIS_LINK or PA_LINK) the returned length grows by sizeof(struct sockaddr_iso_bc), but only bc_sid, bc_num_bis and bc_bis are filled; bc_bdaddr and bc_bdaddr_type, the first 7 bytes of that structure, are never written. An unprivileged process can open a BTPROTO_ISO socket and reach the pad leak with getsockname(); the broadcast leak needs an established BIS/PA connection. l2cap and rfcomm already memset their sockaddr in getname for the same reason; do the same here. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Fixes: 0a766a0affb5 ("Bluetooth: ISO: Fix getpeername not returning sockaddr_iso_bc fields") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: ISO: do not force BT_LISTEN after a failed BIG syncAli Ahmet Memis1-8/+22
commit 9838a80096ba472d5e03057136a112631aabae6e upstream. iso_sock_recvmsg() handles the deferred setup of a broadcast sink by dropping the socket lock, calling iso_conn_big_sync() and taking the lock again: release_sock(sk); iso_conn_big_sync(sk); lock_sock(sk); sk->sk_state = BT_LISTEN; The state is written unconditionally, but iso_conn_big_sync() returns void and has paths that do nothing at all: hci_get_route() may fail, and after re-acquiring the socket lock the connection may already be gone, in which case it bails out without ever issuing an LE BIG Create Sync. While the lock is dropped the connection can be torn down, for example when the controller reports HCI_EV_LE_PA_SYNC_LOST: hci_le_pa_sync_lost_evt() hci_disconn_cfm() -> iso_disconn_cfm() -> iso_conn_del() iso_chan_del() iso_pi(sk)->conn = NULL sk->sk_state = BT_CLOSED sock_set_flag(sk, SOCK_ZAPPED) iso_conn_big_sync() then finds conn == NULL and returns, but the caller still overwrites the BT_CLOSED that iso_chan_del() has just set. The socket ends up marked BT_LISTEN with no connection, so recvmsg() reports success for a setup that never happened and a later accept() waits for BIS connections that can never arrive instead of failing. A concurrent shutdown() reaches the same write by another route: __iso_sock_close() takes the BT_CONNECT2 PA sync path to iso_sock_disconn(), which sets BT_DISCONN but leaves conn and conn->hcon in place, so iso_conn_big_sync() succeeds and BT_LISTEN is written over BT_DISCONN. Both the BT_CONNECT2 and the BT_CONNECTED case write the state the same way. Let iso_conn_big_sync() report whether the BIG sync was started, and only move the socket to BT_LISTEN when it was and when the state has not changed while the lock was dropped, mirroring what the BT_CONNECT case of the same switch already does with iso_connect_cis(). Both conditions are needed, the error alone does not cover the shutdown() race. This corrupts the socket state machine only, it is not a memory safety issue. KASAN and lockdep stayed quiet in all of the runs below. Reproduced with an emulated controller over /dev/vhci on a KASAN + PROVE_LOCKING kernel. A PA sync broadcast sink socket is driven to BT_CONNECT2 and recvmsg() on it is raced against teardown, with a debug delay inside the lock-dropped section to widen the window: - HCI_EV_LE_PA_SYNC_LOST injected: 64 of 64 rounds left the socket in BT_LISTEN with the connection gone, recvmsg() returned 0 and accept() on that fd returned EAGAIN, which iso_sock_accept() can only do while the socket is BT_LISTEN. With this patch, 0 of 64, recvmsg() returns an error and accept() returns EBADFD. - shutdown() instead of a controller event: 24 of 32 rounds wedged in BT_LISTEN, 0 of 32 with this patch. With only the error check in place and a short window, one round still wedged while recvmsg() returned 0, which is the case the state re-check covers. An unraced control round behaves the same before and after: recvmsg() returns 0, the socket reaches BT_LISTEN and an LE BIG Create Sync is issued. Fixes: 7a17308c1788 ("Bluetooth: iso: Fix circular lock in iso_conn_big_sync") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: hci_sync: Fix accept list UAF during suspendChengfeng Ye1-9/+37
commit f57b399c4fa1501b2d5451f52d861ece86bcf3db upstream. hci_update_event_filter_sync() walks hdev->accept_list while sending a synchronous HCI command for each remote-wakeup device. The suspend path holds hdev->req_lock, but accept-list updates are serialized by hdev->lock. Consequently, remove_device() can free the current list entry during the controller wait. The following interleaving causes the use-after-free: hci_update_event_filter_sync() remove_device() fetch accept-list entry hci_set_event_filter_sync() wait for controller response hci_dev_lock() list_del() kfree() hci_dev_unlock() read the freed list.next KASAN reported: BUG: KASAN: slab-use-after-free in hci_suspend_sync+0x835/0x910 Read of size 8 at addr ffff88810bec8440 by task kworker/0:1/10 Workqueue: events vhci_suspend_work Call Trace: hci_suspend_sync+0x835/0x910 hci_suspend_dev+0x182/0x450 process_one_work+0x661/0x1090 worker_thread+0x45b/0xd10 Allocated by task 86: hci_bdaddr_list_add_with_flags+0x1a8/0x400 add_device+0x381/0x820 hci_sock_sendmsg+0x1033/0x1ea0 Freed by task 91: kfree+0x131/0x3c0 remove_device+0x429/0xb70 hci_sock_sendmsg+0x1033/0x1ea0 Snapshot the remote-wakeup addresses under hdev->lock. Release the lock before sending HCI commands. Clear the controller event filter before building the snapshot, and skip allocation and the second list traversal when there are no matching entries. This preserves the original filter and scan-state updates without retaining an accept-list node across a controller wait. Fixes: 182ee45da083 ("Bluetooth: hci_sync: Rework hci_suspend_notifier") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/linux-bluetooth/20260730092331.2069741-1-nicoyip.dev@gmail.com/ Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: hci_event: validate LE Set CIG Parameters responseLaxman Acharya Padhya1-2/+4
commit 0acd4eeb4b225b9bebbf9ef96cc10cdd79b94899 upstream. The Command Complete dispatch validates only the fixed part of the LE Set CIG Parameters response. After that part is pulled from the skb, hci_cc_le_set_cig_params() trusts num_handles and reads each entry in the trailing handle array. Matching num_handles against the command's num_cis does not guarantee that the response contains the advertised handles. A truncated response from a malfunctioning controller can therefore make the handler read beyond the skb data. Validate that the remaining skb data contains all advertised handles. Include this in the existing response validation so malformed responses also follow the established CIG failure handling. Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections") Cc: stable@vger.kernel.org Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: hci_event: fix LE list UAF on resetChengfeng Ye1-0/+2
commit 33af47e847fe4a28b109673affb5874015d54f5a upstream. hci_cc_reset() clears the LE accept and resolving lists without taking hdev->lock. Other command-complete handlers serialize updates to these lists with that lock, and the debugfs readers hold it while walking them. This permits the reset completion and a debugfs read to interleave as follows: hci_rx_work debugfs reader ----------- -------------- lock hdev->lock fetch current entry list_del(entry) kfree(entry) read entry fields The reader then dereferences a freed list entry and may follow its stale next pointer. KASAN reported: BUG: KASAN: slab-use-after-free in white_list_show+0x15f/0x180 Read of size 1 at addr ffff8881015dab16 by task poc/95 Call Trace: white_list_show+0x15f/0x180 seq_read_iter+0x3ff/0x1190 seq_read+0x267/0x3d0 vfs_read+0x177/0xa20 ksys_read+0xf7/0x1c0 Allocated by task 91: hci_bdaddr_list_add+0x1a6/0x3a0 hci_cc_le_add_to_accept_list+0xab/0x140 hci_cmd_complete_evt+0x26c/0x9a0 hci_event_packet+0x454/0xb20 hci_rx_work+0x293/0x730 Freed by task 90: kfree+0x131/0x3c0 hci_bdaddr_list_clear+0xd8/0x160 hci_cc_reset+0x28a/0x370 hci_cmd_complete_evt+0x26c/0x9a0 hci_event_packet+0x454/0xb20 hci_rx_work+0x293/0x730 Take hdev->lock around both list clears. This matches the existing mutation and traversal locking convention. Fixes: a4d5504d5c39 ("Bluetooth: Clear LE white list when resetting controller") Fixes: cfdb0c2d095a ("Bluetooth: Store Resolv list size") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysipv6: fix use-after-free in ip6_finish_output2()Luxiao Xu1-0/+2
commit d0d48d999b0eee6bb176ef4e39d9be868fa80f7e upstream. ip6_finish_output2() caches a pointer to the IPv6 destination address (daddr) before invoking lwtunnel_xmit(). The LWT-BPF transmit path or other encapsulation operations within lwtunnel_xmit() can reallocate the skb head, freeing the memory that daddr points to. When lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, the function continues to use the stale daddr pointer to compute the nexthop and to look up or create the neighbour entry. This results in a use-after-free read, which can leak sensitive kernel data, pollute the neighbour table with arbitrary values, misdirect traffic, or crash the system. Fix this by re-fetching the IPv6 header and the destination address pointer after lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop computation and neighbour lookup operate on valid memory. Fixes: e415ed3a4b8b ("ipv6: use skb_expand_head in ip6_finish_output2") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Luxiao Xu <rakukuip@gmail.com> Signed-off-by: Ren Wei <weir@nebusec.ai> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/4aa3f53bc44e79572c6dd2340ec7b68ef1a3d87d.1786516730.git.rakukuip@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysipv4: reject undersized MTUs in ip_do_fragment()Yong Wang1-0/+4
commit c0726f0caf8c6b3208552949e17d23634a2f3129 upstream. ip_do_fragment() subtracts the IPv4 header length from the effective MTU and passes the resulting payload MTU to ip_frag_next(). If the effective MTU is smaller than hlen + 8, ip_frag_next() rounds the fragment payload length down to zero. The fragmentation state then never makes forward progress: state->left, state->ptr and state->offset stay unchanged while ip_do_fragment() keeps allocating and transmitting header-only fragments until the softlockup detector fires. This is reproducible with a route installed using "mtu lock 20", but it is also reproducible without route MTU lock, for example by forwarding a packet to a device whose MTU is 20. Fix it in ip_do_fragment() by rejecting mtu < hlen + 8 with -EMSGSIZE, matching the existing IPv6 fragmentation check. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Yong Wang <edragain@163.com> Signed-off-by: Ren Wei <weir@nebusec.ai> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/8809ef6314b98913681b0b370a05a85c2b6cd579.1786599079.git.edragain@163.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: nci: free destination parameters when closing a connectionLinmao Li1-0/+1
commit 2e65bafdfd3a8bba972b3d17b6a57816557530fc upstream. When a connection is closed, nci_core_conn_close_rsp_packet() frees conn_info but not conn_info->dest_params, which is a separate devm allocation. Each connect/close cycle leaks one dest_params until the NFC device is removed. Free dest_params along with conn_info. Fixes: 9b8d1a4cf2aa ("nfc: nci: Add an additional parameter to identify a connection id") Cc: stable@vger.kernel.org Signed-off-by: Linmao Li <lilinmao@kylinos.cn> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://patch.msgid.link/20260721023518.1697625-1-lilinmao@kylinos.cn Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: nci: fix uninit-value in the RF discover/activated NTF handlersSamuel Page1-2/+2
commit 8cbe06c1e699c0a165dae5093a2550e65f914818 upstream. nci_rf_discover_ntf_packet() and nci_rf_intf_activated_ntf_packet() each parse a notification into an on-stack struct (nci_rf_discover_ntf / nci_rf_intf_activated_ntf) that is not initialised. The RF technology-specific parameters are only extracted when rf_tech_specific_params_len is non-zero, so a notification that reports a zero length leaves the rf_tech_specific_params union uninitialised - and both handlers then pass it to nci_add_new_protocol(), which reads it: - discover: nci_add_new_target() -> nci_add_new_protocol(); - activated: nci_target_auto_activated() -> nci_add_new_protocol(). nci_add_new_protocol() uses nfca_poll->nfcid1_len as both a branch condition and a memcpy() length and copies nfcid1/sens_res/sel_res into ndev->targets, which is later exposed to user space via NFC_CMD_GET_TARGET. BUG: KMSAN: uninit-value in nci_add_new_protocol+0x624/0x6c0 nci_add_new_protocol+0x624/0x6c0 nci_ntf_packet+0x25b2/0x3c30 nci_rx_work+0x318/0x5d0 process_scheduled_works+0x84b/0x17a0 worker_thread+0xc10/0x11b0 kthread+0x376/0x500 Local variable ntf.i created at: nci_ntf_packet+0xbc2/0x3c30 Zero-initialise both on-stack notifications so the union reads back as zero when no technology-specific parameters are present. Fixes: 019c4fbaa790 ("NFC: Add NCI multiple targets support") Fixes: e8c0dacd9836 ("NFC: Update names and structs to NCI spec 1.0 d18") Link: https://lore.kernel.org/netdev/20260623172109.1105965-2-horms@kernel.org/ Cc: stable@vger.kernel.org Assisted-by: Bynario AI Signed-off-by: Samuel Page <sam@bynar.io> Link: https://patch.msgid.link/20260626090301.2139500-1-sam@bynar.io Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: nci: fix out-of-bounds write in nci_target_auto_activated()Samuel Page1-0/+6
commit ac200079db50af81e6b04d058b33ec92901d8edd upstream. nci_target_auto_activated() appends a target to the fixed-size array ndev->targets[NCI_MAX_DISCOVERED_TARGETS] and increments ndev->n_targets without first checking the array is full; unlike its sibling nci_add_new_target(), which bails out when n_targets already equals NCI_MAX_DISCOVERED_TARGETS. ndev->n_targets is only cleared by nci_clear_target_list(), so an NFCC that repeatedly re-runs discovery (RF_DISCOVER_RSP, which re-enters NCI_DISCOVERY without clearing the target list) and reports an auto-activated target (RF_INTF_ACTIVATED_NTF) drives n_targets past the limit. The append then writes a struct nfc_target past the end of the array (a slab out-of-bounds write), and nfc_targets_found() goes on to walk the array with the inflated count: BUG: KASAN: slab-out-of-bounds in nci_add_new_protocol+0x94/0x2ac [nci] Write of size 2 at addr ffff0000c7299a18 by task kworker/u8:0/12 Workqueue: nfc0_nci_rx_wq nci_rx_work [nci] Call trace: nci_add_new_protocol+0x94/0x2ac [nci] nci_ntf_packet+0xddc/0x11a0 [nci] nci_rx_work+0x15c/0x1e0 [nci] process_one_work+0x2dc/0x500 worker_thread+0x240/0x460 kthread+0x1c0/0x1d0 ret_from_fork+0x10/0x20 The buggy address belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1024 bytes to the right of allocated 1560-byte region [ffff0000c7299000, ffff0000c7299618) Guard nci_target_auto_activated() with the same check used by nci_add_new_target(). Fixes: 019c4fbaa790 ("NFC: Add NCI multiple targets support") Cc: stable@vger.kernel.org Assisted-by: Bynario AI Signed-off-by: Samuel Page <sam@bynar.io> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260622145243.3167276-1-sam@bynar.io Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: nci: add data_len bound checks to activation parameter extractorsBryam Vargas1-4/+22
commit 0428fa2c22e2ba0cff766d3b80d461e149102045 upstream. nci_extract_activation_params_iso_dep() and nci_extract_activation_params_nfc_dep() read an inner length byte from the NCI RF_INTF_ACTIVATED_NTF payload and use it to memcpy() into fixed kernel buffers, but neither function receives the caller-validated activation_params_len. A crafted NCI notification with activation_params_len=1 and an inner length byte of up to 20 (NFC-A) or 50 (NFC-B) causes memcpy() to read that many bytes past the one valid byte in the activation params region -- a slab out-of-bounds read of kernel memory adjacent to the NCI skb. The sibling nci_extract_rf_params_*() family was given equivalent protection by commit 571dcbeb8e63 ("net: nfc: nci: Fix parameter validation for packet data"), but the two activation parameter extractors were not updated at that time. Add a data_len parameter to both functions, guard against an empty region before consuming the inner length byte, decrement the remaining count after consuming it, and clamp the copy length to what is actually available. Update both call sites to pass ntf.activation_params_len, which is already validated against the skb at ntf.c:801. Fixes: e8c0dacd9836 ("NFC: Update names and structs to NCI spec 1.0 d18") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me> Link: https://patch.msgid.link/20260612-b4-disp-6d52d8b0-v3-1-e26221f8826d@proton.me Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: llcp: reject PDUs shorter than the LLCP headerDoruk Tan Ozturk1-0/+5
commit 95674f506c6376d6722a23144c9acd26609771ed upstream. Every LLCP PDU begins with a two-byte header (DSAP/SSAP + PTYPE), but the receive path never checked that a frame is at least LLCP_HEADER_SIZE bytes before parsing it. nfc_llcp_rx_skb() reads the header via nfc_llcp_ptype()/nfc_llcp_dsap()/ nfc_llcp_ssap(), which dereference pdu->data[0] and pdu->data[1], and a CONNECT or CC PDU then computes tlv_array_len = skb->len - LLCP_HEADER_SIZE; as a size_t and hands it to the TLV walk. When the frame is shorter than the header the subtraction wraps to a huge value and the walk runs far past the buffer, an out-of-bounds read. A nearby NFC device can reach this without authentication; LLCP link activation happens automatically after NFC-DEP. Guard the common receive choke point __nfc_llcp_recv(), shared by both the target (nfc_llcp_data_received()) and initiator (nfc_llcp_recv()) paths, so a short skb is dropped before the rx_work worker parses it. Use pskb_may_pull() rather than a skb->len test so the two header bytes are guaranteed to sit in the skb linear area even for a non-linear skb, matching how the sibling NCI and HCI receive paths validate their headers. Reproduced with a KFENCE out-of-bounds read via /dev/virtual_nci on linux-next. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: d646960f7986 ("NFC: Initial LLCP support") Cc: stable@vger.kernel.org Suggested-by: David Laight <david.laight.linux@gmail.com> Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://patch.msgid.link/20260714164631.75068-1-doruk@0sec.ai Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: llcp: fix OOB read and u8 offset wrap in TLV parsersMuhammad Bilal1-2/+16
commit 78b20c8eeacd2e44a2d8a4cb5316d3c521d90911 upstream. nfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv() contain three related bugs in their TLV parsing loops: 1. 'offset' is declared u8 but tlv_array_len is u16. When TLV data advances offset past 255 it silently wraps to zero, causing infinite loops or double-processing of buffer data. 2. Before reading tlv[0] (type) and tlv[1] (length) there is no check that offset+2 <= tlv_array_len. A truncated TLV causes an OOB read of one byte past the buffer end. 3. After reading the length field, the value bytes are accessed without checking offset+2+length <= tlv_array_len. A crafted length=0xFF on a short buffer causes up to 255 bytes of OOB read past the buffer end. Both functions are reachable without authentication via nfc_llcp_set_remote_gb() which feeds remote LLCP general bytes directly into nfc_llcp_parse_gb_tlv() with no additional validation. Fix all three issues by widening offset from u8 to u16 and adding bounds checks for both the TLV header and value field before each access. Fixes: 3df40eb3a2ea ("nfc: constify several pointers to u8, char and sk_buff") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal <meatuni001@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260622131802.239035-1-meatuni001@gmail.com Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: llcp: bound the connect_sn TLV walk to the skbDoruk Tan Ozturk1-4/+6
commit 55c68ac93e7dacc0f5f608b9c39dd4ff48cf28e8 upstream. Commit 27256cdb290e ("nfc: llcp: bound SNL TLV parsing to the skb and add length checks") fixed the unbounded TLV walk in nfc_llcp_recv_snl(), and commit d8bd2dedbde5 ("nfc: llcp: fix OOB read and u8 offset wrap in TLV parsers") subsequently bounded nfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv(). One sibling parser sharing the same pattern remains unbounded: nfc_llcp_connect_sn(). nfc_llcp_connect_sn() walks a TLV list, reading a two-byte header (type, length) followed by length bytes of value, without checking that the two header bytes or the declared length stay within the buffer. It returns a pointer to a service name of up to 255 bytes that may point past the end of the skb; it is subsequently consumed by memcmp() in nfc_llcp_sock_from_sn(). In addition tlv_array_len was computed as "skb->len - LLCP_HEADER_SIZE" in size_t, so a CONNECT/CC frame shorter than the LLCP header underflows to a huge length and the walk runs far past the buffer. nfc_llcp_connect_sn() is reachable from nfc_llcp_recv_connect() and nfc_llcp_recv_cc(), i.e. from received CONNECT and CC PDUs. A nearby NFC device can reach this without authentication; LLCP link activation happens automatically after NFC-DEP, and the nfc_llcp_rx_skb() dispatcher applies no minimum-length guard. Walk the TLV list by pointer, bounded by skb_tail_pointer(skb), and validate each declared length before use, matching the approach already used for nfc_llcp_recv_snl(). Starting the walk at &skb->data[LLCP_HEADER_SIZE] against the tail pointer also removes the size_t underflow for short frames. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: d646960f7986 ("NFC: Initial LLCP support") Cc: stable@vger.kernel.org Assisted-by: 0sec:claude-opus-4-8 Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260709131229.44477-1-doruk@0sec.ai Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysnfc: digital: clamp SENSF_RES length to the destination bufferDoruk Tan Ozturk1-0/+2
commit 344a56d7c8e0f3cbaff0bcb1bcd95a1a1db24b16 upstream. digital_in_recv_sensf_res() memcpy()s resp->len bytes from a remote NFC-F device response into the NFC_SENSF_RES_MAXSIZE-byte target.sensf_res field without an upper-bound check. A nearby malicious NFC-F device can send an oversized SENSF_RES response to overflow the stack-local struct nfc_target. Clamp resp->len to NFC_SENSF_RES_MAXSIZE before the copy. Found by 0sec automated security-research tooling (https://0sec.ai). Fixes: 8c0695e4998d ("NFC Digital: Add NFC-F technology support") Cc: stable@vger.kernel.org Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://patch.msgid.link/20260603141355.68156-1-doruk@0sec.ai Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 daysBluetooth: RFCOMM: take rfcomm_mutex for the deferred setup acceptAli Ahmet Memis1-3/+21
commit 43a556b2fd43f2df6dded59c2e26560a27874c24 upstream. rfcomm_sock_recvmsg() completes a deferred setup by calling rfcomm_dlc_accept() without holding any RFCOMM lock: if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) { rfcomm_dlc_accept(d); return 0; } and rfcomm_dlc_accept() dereferences the session on its first line: struct sock *sk = d->session->sock->sk; Every other path that touches d->session runs under rfcomm_mutex: rfcomm_dlc_open(), rfcomm_dlc_close(), rfcomm_dlc_exists(), rfcomm_dlc_send_rpn(), and the RFCOMM thread through rfcomm_process_sessions(). rfcomm_connect_ind() is even documented as "called under rfcomm_lock()". This call site is the only one that skips it. The RFCOMM_DEFER_SETUP bit looks like it serialises the accept against teardown, since __rfcomm_dlc_close() returns early when it wins the test_and_clear. But rfcomm_recv_disc() forces the state first: d->state = BT_CLOSED; __rfcomm_dlc_close(d, err); and the early return only covers BT_CONNECT, BT_CONFIG, BT_OPEN and BT_CONNECT2. With the state already BT_CLOSED that switch does not match, the bit is never consulted, and __rfcomm_dlc_close() falls through to rfcomm_dlc_unlink(), which sets d->session = NULL. So a remote DISC on a deferred dlc clears the session while leaving RFCOMM_DEFER_SETUP set. The next recvmsg() then passes the test_and_clear and dereferences a NULL session. No timing window is needed: once the DISC has been processed, the dereference is unconditional. Give rfcomm_dlc_accept() the same shape as rfcomm_dlc_open() and rfcomm_dlc_close(): an exported wrapper that takes rfcomm_mutex and re-checks the session, around a __rfcomm_dlc_accept() that the two in-core callers, which already hold the mutex, keep using. Reproduced on a KASAN + PROVE_LOCKING kernel with a BR/EDR peer emulated over /dev/vhci: the peer brings up an ACL link, opens L2CAP on the RFCOMM PSM, starts a session, opens a dlc on a channel bound with BT_DEFER_SETUP, and sends DISC after the socket is accepted. recv() on the accepted socket then hits: Oops: general protection fault KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:rfcomm_dlc_accept+0x54/0x350 Call Trace: rfcomm_sock_recvmsg+0x1cd/0x230 sock_recvmsg+0x166/0x1c0 __sys_recvfrom+0x20d/0x300 0x10 is the offset of sock in struct rfcomm_session. With this patch the same run completes with recv() returning 0 and no report, and lockdep stays quiet, confirming rfcomm_mutex is still taken before lock_sock on this path as it is on the thread side. Fixes: bb23c0ab8246 ("Bluetooth: Add support for deferring RFCOMM connection setup") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14Merge tag 'ceph-for-7.2-rc8' of https://github.com/ceph/ceph-clientLinus Torvalds4-16/+25
Pull ceph fixes from Ilya Dryomov: "A handful of tiny fixes, with the main ones being a follow-up for CEPH_IOC_SET_LAYOUT{,_POLICY} ioctl permissions check that went into rc5 and a userspace compatibility fixup. The rest mostly harden against malformed network input. All marked for stable" * tag 'ceph-for-7.2-rc8' of https://github.com/ceph/ceph-client: ceph: use the mount idmap for the owner checks in the SET_LAYOUT ioctls ceph: fix MDS random selection readiness predicate libceph: Avoid using invalid osd indices from primary_temp libceph: fix OOB read in decode_watchers() via missing bounds check libceph: fix multiple unsafe decodes in decode_locker() libceph: tolerate addrvecs with multiple entries of the same type
2026-08-13Merge tag 'net-7.2-rc8' of ↵Linus Torvalds44-195/+528
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from netfilter. There is a known WiFi/mt76 regression, waiting for a complete fix that should land soonish. Previous releases - regressions: - tcp: fix icsk_ack.ato bitfield overflow - af_unix: Unlink scc_entry in unix_del_edge() - ipv4: fix use-after-free in fib_nhc_update_mtu() - netfilter: - ipset: fix refcount race between list:set GC and swap - nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path - sched: act_ct: fix sk_buff leak when the header checks reject a packet - sctp: clear new_transport when removing a peer - dibs: correct freeing of dmb_clientid_arr - ovpn: fix NULL dereference when killing missing key - eth: - veth: fix queue index used to wake the peer txq in veth_poll - ngbe: fix NULL pointer dereference in non-MSI-X interrupt enabling - gve: fix zero-length skb frag with header-split Previous releases - always broken: - core: fix skb length accounting after generic XDP frag adjustment - af_packet: don't send zero-byte data in tpacket_snd(). - eth: - bnxt: avoid deadlock when canceling IRQ affinity notifier - ipvlan: inherit needed_headroom and needed_tailroom from phy_dev" * tag 'net-7.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (55 commits) l2tp: fix tunnel and session refcount leak on seq_file release net/sched: cls_bpf: reject dev-bound programs bound to a different device sctp: fix use-after-free of cached ASCONF chunk net: ethernet: ti: am65-cpsw-nuss: Fix port_id extraction from SRC TAG sctp: clear new_transport when removing a peer net/dibs: Correct freeing of dmb_clientid_arr net/sched: cls_u32: skip hash tables in u32_bind_class() gve: fix NULL dereference due to missing ptp adjfine gve: fix zero-length skb frag with header-split net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain af_packet: Don't send zero-byte data in tpacket_snd(). tipc: read le->link under the node lock in tipc_node_link_down() selftests: tls: cover splice after a failed decrypt net/tls: Fail tls_sw_splice_read() after a failed async decrypt net: ngbe: fix NULL pointer dereference in non-MSI-X interrupt enabling net: tap: fix wrong transport_header when sending VLAN-tagged frame net: packet: fix wrong transport_header when sending VLAN-tagged frame vxlan: do not arm the ageing timer on a device that is down ipv4: fix use-after-free in fib_nhc_update_mtu() NTB: ntb_netdev: Preserve RX queue depth on allocation failure ...
2026-08-13l2tp: fix tunnel and session refcount leak on seq_file releaseEric Dumazet2-3/+57
In pppol2tp_proc_open() and l2tp_dfs_seq_open(), iteration state (pd->tunnel and pd->session) is kept in seq_file private data to allow iteration across multiple read() system calls. However, if userspace closes /proc/net/pppol2tp or /sys/kernel/debug/l2tp/tunnels before reading to end-of-file (EOF), any tunnel or session reference stored in pd->tunnel / pd->session is left un-dropped when seq_file private data is freed. Fix this by dropping any remaining pd->tunnel and pd->session references in pppol2tp_proc_release() and l2tp_dfs_seq_release() when closing the file. Fixes: 0e0c3fee3a59 ("l2tp: hold reference on tunnels printed in pppol2tp proc file") Fixes: f726214d9b23 ("l2tp: hold reference on tunnels printed in l2tp/tunnels debugfs file") Reported-by: syzbot+d6fa74e3f19d6ee01e3a@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a760f32.01d0871a.3a0d52.004f.GAE@google.com/T/#u Assisted-by: Jetski:Gemini-3.1-Pro Cc: James Chapman <jchapman@katalix.com> Cc: Guillaume Nault <gnault@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260811144651.2733424-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-13net/sched: cls_bpf: reject dev-bound programs bound to a different deviceJamal Hadi Salim1-2/+16
cls_bpf_prog_from_efd() obtained a SCHED_CLS program via bpf_prog_get_type_dev() but never verified that a device-bound (offloaded) program's bound netdev matches the TC netdev the classifier is being attached to. This let a program loaded with prog_ifindex for device A be attached via cls_bpf + skip_sw to device B; deleting device A then destroyed the program's offload state while it was still attached to device B, triggering a netdevsim WARN (panic with panic_on_warn=1). Mirror the XDP attach path (net/core/dev.c) and reject the attach with -EINVAL when a dev-bound program's bound device does not match the target device. Fixes: 2b3486bc2d23 ("bpf: Introduce device-bound XDP programs") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260809094418.901607-1-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-13sctp: fix use-after-free of cached ASCONF chunkYuxiang Yang2-2/+8
addip_last_asconf caches the outstanding outbound ASCONF chunk. The normal ASCONF-ACK completion path releases the chunk and clears the pointer. However, sctp_asconf_queue_teardown() releases the cached chunk without clearing addip_last_asconf. During peer restart handling, sctp_sf_do_dupcook_a() queues SCTP_CMD_PURGE_ASCONF_QUEUE, which invokes sctp_asconf_queue_teardown() while the association remains alive and leaves the pointer dangling. A delayed authenticated ASCONF-ACK can then reach sctp_sf_do_asconf_ack(), which accesses the stale chunk and passes it to sctp_process_asconf_ack(), causing a use-after-free and a second release. Clearing the pointer exposes a race with T4 expiry. Peer restart handling queues the timer stop before the purge, but SCTP_CMD_TIMER_STOP uses timer_delete(), which does not wait for a callback already running on another CPU. Such a callback can reach sctp_sf_t4_timer_expire() after the purge and dereference NULL. Clear addip_last_asconf after releasing the cached chunk, and make sctp_sf_t4_timer_expire() consume a stale T4 expiry if no outstanding ASCONF remains. Fixes: a000c01e60e4 ("sctp: stop pending timers and purge queues when peer restart asoc") Cc: stable@vger.kernel.org Suggested-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/20260809043806.2768302-1-yangyx22@mails.tsinghua.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-13sctp: clear new_transport when removing a peerQing Ming1-0/+3
sctp_process_asconf_param() stores a newly added peer transport in asoc->new_transport. After all parameters in the ASCONF chunk have been processed, sctp_sf_do_asconf() uses this pointer to send a HEARTBEAT to the new transport. An authenticated ASCONF from a remote SCTP peer can add a transport and remove it again with a wildcard DEL-IP parameter in the same chunk. The wildcard deletion preserves the transport on which the ASCONF arrived, but removes the newly added transport through sctp_assoc_del_nonprimary_peers(). The removal does not clear asoc->new_transport, leaving it pointing to the removed transport. sctp_sf_do_asconf() then creates a HEARTBEAT whose chunk->transport points to the removed transport without holding a transport reference. During local address replacement, src_out_of_asoc_ok keeps this HEARTBEAT on control_chunk_list. After the transport is freed by RCU, a successful ASCONF_ACK for the replacement address releases the queued HEARTBEAT and sctp_outq_select_transport() reads the freed transport's state. The issue was found during a static audit of SCTP objects. With an authenticated peer, the reproducer triggered the same KASAN report in 2 of 2 unpatched runs on a KASAN-enabled netdev/main kernel: BUG: KASAN: slab-use-after-free in sctp_outq_select_transport Read of size 4 at addr ffff88800b9bd95c by task python3/197 Call Trace: sctp_outq_select_transport+0x549/0x8b0 [sctp] sctp_outq_flush+0x306/0x2c60 [sctp] sctp_transport_immediate_rtx+0xaf/0x260 [sctp] sctp_process_asconf_ack+0xa48/0xf70 [sctp] Allocated by task 197: sctp_transport_new+0x68/0x650 [sctp] sctp_assoc_add_peer+0x258/0x12a0 [sctp] sctp_process_asconf+0x5e9/0x1090 [sctp] Last potentially related work creation: __call_rcu_common.constprop.0+0x77/0xb70 sctp_assoc_del_nonprimary_peers+0x7c/0xd0 [sctp] sctp_process_asconf+0xd9c/0x1090 [sctp] The first invalid access was a four-byte read of transport->state at net/sctp/outqueue.c:833. The same reproducer completed the full authenticated ASCONF and local-address replacement sequence with this change without a KASAN report or oops. Clear new_transport when its peer is removed, before it can be used to create the HEARTBEAT. Fixes: 6af29ccc223b ("sctp: Bundle HEAERTBEAT into ASCONF_ACK") Cc: stable@vger.kernel.org Signed-off-by: Qing Ming <a0yami@mailbox.org> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/20260811152803.5629-1-a0yami@mailbox.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-12libceph: Avoid using invalid osd indices from primary_tempRaphael Zimmer1-2/+3
A corrupted osdmap received from a Ceph monitor or OSD may contain osd indices in its pg_temp, primary_temp, pg_upmap, and pg_upmap_items parts that don't exist, i.e., that are greater than max_osd or smaller than CEPH_HOMELESS_OSD (-1). These indices are used to create the up and acting set in ceph_pg_to_up_acting_osds(), called from calc_target(). While most of these osd indices are checked, the one from primary_temp is not. Subsequently, this may lead to calc_target() returning this (potentially invalid) index as target osd for a (linger) request. Because the osd_state, osd_weight, and osd_addr arrays only contain max_osd entries (with indices 0 to max_osd -1), this leads to out-of-bounds accesses when trying to read values from these arrays. This patch fixes the issue by adding a check to get_temp_osds(), so that only valid osd indices from primary_temp are used, and it falls back to using the primary from pg_temp or the up set if it is invalid. [ idryomov: changelog ] Cc: stable@vger.kernel.org Fixes: 5e8d4d36bf23 ("libceph: add support for primary_temp mappings") Signed-off-by: Raphael Zimmer <raphael.zimmer@tu-ilmenau.de> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-08-12libceph: fix OOB read in decode_watchers() via missing bounds checkPavitra Jha1-1/+4
ceph_start_decoding() validates that struct_len bytes remain in the buffer after the encoding header, but accepts struct_len=0 as valid: ceph_decode_need(p, end, 0, bad) always passes. When a malicious or compromised OSD sends an obj_list_watch_response_t reply with struct_len=0, ceph_start_decoding() returns success with p == end, leaving zero bytes guaranteed for subsequent reads. The immediately following ceph_decode_32(p) in decode_watchers() has no preceding bounds check. With p == end this is a 4-byte read past the validated buffer boundary. The garbage value is then passed directly to kzalloc_objs() as the watcher count. The sibling function decode_watcher() already uses the safe variants (ceph_decode_copy_safe, ceph_decode_64_safe, ceph_decode_skip_32) after its own ceph_start_decoding() call. decode_watchers() is the only site that uses the bare variant, confirming an oversight. Fix by replacing ceph_decode_32(p) with ceph_decode_32_safe(p, end, *num_watchers, bad), consistent with the established pattern. Attacker model: a malicious or compromised OSD in a multi-tenant Ceph deployment (e.g. cloud) can trigger this against any kernel client that calls CEPH_OSD_OP_LIST_WATCHERS, without any further privileges beyond OSD session establishment. [ idryomov: trim changelog ] Cc: stable@vger.kernel.org Fixes: a4ed38d7a180 ("libceph: support for CEPH_OSD_OP_LIST_WATCHERS") Signed-off-by: Pavitra Jha <jhapavitra98@gmail.com> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-08-12libceph: fix multiple unsafe decodes in decode_locker()Pavitra Jha1-4/+9
decode_locker() in cls_lock_client.c contains three unsafe decode operations that allow a malicious or compromised OSD to trigger slab-out-of-bounds reads: 1. ceph_decode_copy() at the locker_id_t name field has no preceding bounds check. With p == end after ceph_start_decoding() accepts struct_len=0, this reads sizeof(ceph_entity_name) = 9 bytes past the validated buffer boundary. 2. *p += sizeof(struct ceph_timespec) after the locker_info_t header is an unchecked pointer advance. A malicious OSD can position p past end, causing all subsequent _safe checks to pass against a bogus boundary. 3. len = ceph_decode_32(p) has no preceding bounds check, and the immediately following *p += len is uncapped. A malicious OSD can send len=0xffffffff, advancing p gigabytes past end and escaping the decode window entirely. Fix all three by replacing bare operations with their safe variants: ceph_decode_copy -> ceph_decode_copy_safe *p += sizeof(...) -> ceph_decode_skip_n ceph_decode_32(p) -> ceph_decode_32_safe *p += len -> ceph_decode_skip_n A new label is added to return -EINVAL on any bounds violation. -EINVAL is appropriate here: the data received from the OSD is structurally malformed, which is an invalid argument to the decode contract regardless of whether the caller or the wire is at fault. Attacker model: a malicious or compromised OSD in a multi-tenant Ceph deployment can trigger this against any kernel client that issues the lock.get_info class method (e.g. during RBD exclusive lock acquisition) without any further privileges beyond OSD session establishment. [ idryomov: use ceph_decode_skip_string() to skip description, trim changelog ] Cc: stable@vger.kernel.org Fixes: d4ed4a530562 ("libceph: support for lock.lock_info") Signed-off-by: Pavitra Jha <jhapavitra98@gmail.com> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-08-12libceph: tolerate addrvecs with multiple entries of the same typeKefu Chai1-9/+9
ceph_decode_entity_addrvec() rejects any addrvec containing more than one entry that matches the requested msgr type (LEGACY or MSGR2), logging "another match of type N in addrvec" and returning -EINVAL. Some admin tooling (e.g. pveceph mon create from Proxmox VE) generates addrvecs with multiple same-type entries when public_network lists more than one CIDR: it picks one local IP per subnet and emits both a v2 and a v1 entry for each IP. Monmaps shaped this way cause: libceph: mon0 (1)10.10.10.15:6789 session established libceph: another match of type 1 in addrvec libceph: problem decoding monmap, -22 No Ceph code uses the extra entries: since Nautilus, the userspace messenger (AsyncMessenger) unconditionally picks the first address of the requested type and ignores any subsequent matches. Match that behavior: use the first matching entry and silently skip any subsequent ones. This is a compatibility fix for existing deployments and does not enable dual-stack or multi-subnet address selection. [ idryomov: tweak ceph_decode_entity_addrvec() comment ] Cc: stable@vger.kernel.org Fixes: a5cbd5fc22d5 ("libceph, ceph: get and handle cluster maps with addrvecs") Link: https://bugzilla.proxmox.com/show_bug.cgi?id=7518 Signed-off-by: Kefu Chai <k.chai@proxmox.com> Reviewed-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-08-12Merge tag 'nf-26-08-10' of ↵Jakub Kicinski22-141/+247
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following patchset contains Netfilter/IPVS fixes for net. Still large batch for this late -rc cycle but at least half of these fixes in this batch have been cooking for several weeks before: 1) Fix race between ipset list:set GC and swap, use write_lock instead of rcu read lock section when accessing the index to ensure interference with ip_set_swap(), from Xiang Mei. 2) Release template conntrack in bridge conntrack when packet is neither IPv4 nor IPv6 before setting skb as untracked. From Zhiling Zou. 3) A series of 3 patches for IPVS to address sashiko reports: Schedulers read destination overload state while connection accounting and destination configuration can update it concurrently. The first patch adds a single total connection counter. The second patch uses it to identify threshold crossings precisely, and updates OVERLOAD at the crossings and on a threshold edit under dst_lock. The third patch moves configuration-controlled AVAILABLE to a separate cflags word, so it cannot clobber OVERLOAD through an unrelated read-modify-write update. 4) Log invalid packets in TCP and SCTP connection tracking to address a deadlock when nfnetlink_log is used as logging backend and the nfnetlink_log conntrack glue support is used. From Zihan Xi. 5) Wait for rcu grace period before releasing pernet state in nfnetlink_log, otherwise packets can end up access already released memory, triggering UaF. From Florian Westphal. 6) IPVS needs to reset IP information in control buffer in skbuff when encapsulating IP packets in ICMP, from Kyle Zeng. 7) IPVS needs to validate ihl field of inner headers in when handling ICMP response, from Julian Anastasov. 8) Remove a WARN_ON_ONCE reachable from the nf_tables hardware offload when triggering ENOMEM on GFP_KERNEL allocation, from Alexey Velichayshiy. 9) Publish reply tuple into the flowtable hashtable first, otherwise GC might walk over a released tuple when insertion of the original tuple fail. From Jeremy Jean. 10) Elide counter increment when replacing an ipset element, from Florian Westphal. 11) Remove unneeded ipset accounting resets on destruction/flush, from Florian Westphal. * tag 'nf-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: ipset: let destroy callbacks adjust ext mem size netfilter: ipset: fix list type element drift bug netfilter: flowtable: publish GC-visible tuple last netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path ipvs: revalidate ihl to prevent out-of-bounds access ipvs: clear IPv4 options after rebasing tunnel ICMP errors netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state netfilter: nf_conntrack: defer invalid log until after unlock ipvs: separate destination availability state ipvs: properly update the overload flag on dest edit ipvs: add totalconns for dest netfilter: bridge: release template ct on non-IP path netfilter: ipset: fix refcount race between list:set GC and swap ==================== Link: https://patch.msgid.link/20260810190621.894119-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-12net/sched: cls_u32: skip hash tables in u32_bind_class()Zhang Changzhong1-0/+3
u32_walk() enumerates both struct tc_u_hnode and struct tc_u_knode through the walker callback. u32_bind_class() unconditionally casts the passed fh to tc_u_knode and accesses &n->res, so when fh is actually a tc_u_hnode, which has no tcf_result member, this results in a slab-out-of-bounds read of res->classid in tc_cls_bind_class(). The issue can be reproduced with the following commands: tc qdisc add dev lo root handle 1: hfsc tc class add dev lo parent 1: classid 1:1 hfsc sc rate 1000kbit tc filter add dev lo parent 1:1 protocol ip prio 1 u32 match u32 0 0 flowid 1:1 tc class add dev lo parent 1: classid 1:2 hfsc sc rate 2000kbit Fix this by skipping hash tables via the TC_U32_KEY(handle) check. Fixes: 07d79fc7d94e ("net_sched: add reverse binding for tc class") Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/1786089038-36366-1-git-send-email-zhangchangzhong@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-12net/sched: act_api: fix TOCTOU NULL deref on a->goto_chainJamal Hadi Salim1-5/+5
tcf_action_exec() handles TC_ACT_GOTO_CHAIN by first checking rcu_access_pointer(a->goto_chain) and then calling tcf_action_goto_chain_exec(), which does a second, independent rcu_dereference_bh(a->goto_chain) read and immediately dereferences chain->filter_chain. A concurrent tcf_action_set_ctrlact() (e.g. the gact replace path) can clear a->goto_chain between the two reads, so the second read returns NULL and tcf_action_goto_chain_exec() dereferences NULL. Fix the race by doing a single rcu_dereference_bh() read of a->goto_chain in tcf_action_exec(), checking it once for NULL, and passing the resulting chain pointer into tcf_action_goto_chain_exec(). This turns the split check/use into a single check/use on one value. Fixes: ee3bbfe806cd ("net/sched: let actions use RCU to access 'goto_chain'") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Davide Caratti <dcaratti@redhat.com> Link: https://patch.msgid.link/20260809090928.868186-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-12af_packet: Don't send zero-byte data in tpacket_snd().Eric Dumazet1-0/+3
syzbot reported a WARNING in __dev_queue_xmit() triggered via tpacket_snd(): skb_assert_len WARNING: at include/linux/skbuff.h:2753 skb_assert_len WARNING: at __dev_queue_xmit+0x21bc/0x4970 net/core/dev.c:4781 Call Trace: <TASK> dev_queue_xmit include/linux/netdevice.h:3448 [inline] packet_xmit+0x243/0x310 net/packet/af_packet.c:276 tpacket_snd net/packet/af_packet.c:2907 [inline] packet_sendmsg+0x28d6/0x4eb0 net/packet/af_packet.c:3134 When sending 0-byte packets via TPACKET ring buffer on devices with no hard header (e.g. dev->hard_header_len == 0), tpacket_fill_skb() populates an skb with skb->len == 0 and returns 0. tpacket_snd() then forwards this empty skb to packet_xmit(), causing __dev_queue_xmit() to hit skb_assert_len(skb). Similar checks exist in packet_snd() via commit dc633700f00f ("net/af_packet: check len when min_header_len equals to 0") and in packet_sendmsg_spkt() via commit 6a341729fb31 ("af_packet: Don't send zero-byte data in packet_sendmsg_spkt()."). Return -EINVAL in tpacket_fill_skb() when skb->len is zero to reject zero-length packets in tpacket_snd(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+30b93b6845b19cc38581@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a79e807.01d0871a.3a0d52.00ac.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260810150447.1220864-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-11tipc: read le->link under the node lock in tipc_node_link_down()Jun Yang1-5/+10
tipc_node_link_down() caches the link pointer before taking n->lock: struct tipc_link *l = le->link; /* unlocked */ if (!l) return; tipc_node_write_lock(n); if (!tipc_link_is_establishing(l)) { /* deref l */ ... tipc_link_reset(l); /* write into l */ if (delete) { kfree(l); le->link = NULL; The delete=true caller frees that very object under n->lock, so the lock does not protect the cached pointer against it: - CPU A, delete=false: tipc_rcv() on TIPC_LINK_DOWN_EVT, or the link supervision timer via tipc_node_timeout(), reads l unlocked and then dereferences it under n->lock; - CPU B, delete=true: netlink TIPC_NL_BEARER_DISABLE -> bearer_disable() -> tipc_node_delete_links() -> tipc_node_link_down(n, bearer_id, true) -> kfree(l). The link is freed with plain kfree(), not kfree_rcu(), and for UDP bearers disable_media() only schedules the asynchronous cleanup_bearer() work, so its synchronize_net() runs after the links are already gone. An in-flight CPU A that has read l therefore dereferences freed memory once B frees it: a use-after-free read in tipc_link_is_establishing(), and a use-after-free write via tipc_link_reset() on the establishing branch. The following trace was captured on 7.2.0-rc5-00284-gaf39eb111ce6: BUG: KASAN: slab-use-after-free in tipc_link_is_establishing (net/tipc/link.c:285) Read of size 4 at addr ffff88802e2aa068 by task swapper/2/0 tipc_link_is_establishing (net/tipc/link.c:285) tipc_node_link_down (net/tipc/node.c:1076) tipc_node_timeout (net/tipc/node.c:843) Allocated by task 9549: tipc_link_create (net/tipc/link.c:490) tipc_node_check_dest (net/tipc/node.c:1279) tipc_disc_rcv (net/tipc/discover.c:252) tipc_udp_recv (net/tipc/udp_media.c:389) Freed by task 9549: tipc_node_link_down (net/tipc/node.c:1084) tipc_node_delete_links (net/tipc/node.c:1320) bearer_disable (net/tipc/bearer.c:414) __tipc_nl_bearer_disable (net/tipc/bearer.c:992) Move the le->link read inside tipc_node_write_lock(), so it is serialised against the kfree() in the delete path. A racing teardown now either has not run yet, and we see a valid link, or has already run, and we see NULL. Fixes: 73f646cec354 ("tipc: delay ESTABLISH state event when link is established") Cc: stable@kernel.org Reported-by: TencentOS Corvus AI <corvus@tencent.com> Assisted-by: tencentos-corvus-ai:kimi-k3 Signed-off-by: Jun Yang <junvyyang@tencent.com> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20260810102147.48191-1-juny24602@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-11net/tls: Fail tls_sw_splice_read() after a failed async decryptChuck Lever1-0/+5
When an async decrypt fails, tls_decrypt_done() records the error in ctx->async_wait.err and calls tls_err_abort(), which stores it in sk_err. tls_sw_recvmsg() and tls_sw_read_sock() each read async_wait.err once they hold the reader lock and fail the call: a record that did not authenticate breaks the connection. tls_sw_splice_read() has no such check, and sk_err does not stand in for one. tls_rx_rec_wait() tests sk_err only inside the loop it skips whenever a record is already parsed, and the first reader to reach sock_error() clears it, while async_wait.err persists. A splice therefore keeps delivering records on a connection that recvmsg() and read_sock() refuse to read. Read async_wait.err in tls_sw_splice_read() as the other two readers do. Fixes: f314bfee81b1 ("tls: rx: return the already-copied data on crypto error") Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Chuck Lever <cel@kernel.org> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/20260806-tls-splice-crypto-fix-v1-1-a2624005a286@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-11net: packet: fix wrong transport_header when sending VLAN-tagged frameWei Fang1-2/+2
In packet_parse_headers(), when processing a VLAN-tagged frame, skb_set_network_header() is called to advance network_header past the VLAN tag to the inner protocol header. skb_probe_transport_header() is then called with skb->protocol still set to the outer VLAN EtherType (e.g. ETH_P_8021Q), while nhoff (derived from skb_network_offset()) already points past the VLAN tag to the inner protocol header. In __skb_flow_dissect(), proto is initialized to ETH_P_8021Q and nhoff points past the VLAN tag. When the dissector hits case ETH_P_8021Q, it reads a struct vlan_hdr at nhoff via __skb_header_pointer(), but that offset contains the inner protocol header (e.g. an IP header). The bytes are misinterpreted as a VLAN header, yielding a garbage encapsulated EtherType that matches no known protocol. The dissector returns false, so skb_probe_transport_header() never calls skb_set_transport_header(), leaving transport_header at its uninitialized sentinel value (~0U). Move skb_probe_transport_header() to before skb_set_network_header(). At the time skb_probe_transport_header() is called, network_header still points to the VLAN header, so nhoff correctly points to the VLAN header. The flow dissector can then parse the VLAN header, extract the inner EtherType, and advance nhoff to the inner protocol header, allowing transport_header to be set correctly. Fixes: dfed913e8b55 ("net/af_packet: add VLAN support for AF_PACKET SOCK_RAW GSO") Assisted-by: WChat:claude-opus-4-8 Signed-off-by: Wei Fang <wei.fang@nxp.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260807063405.688780-2-wei.fang@oss.nxp.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-11ipv4: fix use-after-free in fib_nhc_update_mtu()Chengfeng Ye2-23/+40
fib_nhc_update_mtu() walks the nexthop exception table under RTNL, but RTNL does not serialize this walk with PMTU exception updates. The walk uses rcu_dereference_protected() with a constant true condition without holding fnhe_lock. The following interleaving can therefore occur: CPU 0 CPU 1 fib_nhc_update_mtu() update_or_create_fnhe() load fnhe spin_lock_bh(&fnhe_lock) fnhe_remove_oldest() unlink fnhe kfree_rcu(fnhe, rcu) <quiescent state> access fnhe after grace period KASAN reported: BUG: KASAN: slab-use-after-free in fib_nhc_update_mtu+0x3df/0x410 Read of size 8 at addr ffff888107d49000 by task poc/90 Call Trace: fib_nhc_update_mtu+0x3df/0x410 fib_sync_mtu+0x7a/0xd0 fib_netdev_event+0x229/0x3f0 netif_set_mtu_ext+0x33a/0x570 dev_set_mtu+0x88/0x120 The same walk updates fnhe_pmtu and fnhe_mtu_locked. These fields form a pair and other writers serialize them with fnhe_lock. RCU alone prevents reclamation, but would still allow concurrent writers to leave a mixed pair. Walk the table under RCU and acquire fnhe_lock only while updating each exception. RCU keeps the current entry alive while the short critical section serializes its paired PMTU fields. This avoids holding the global lock while scanning all 2048 buckets for every nexthop. Fixes: af7d6cce5369 ("net: ipv4: update fnhe_pmtu when first hop's MTU changes") Cc: stable@vger.kernel.org Suggested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260807181710.1178747-1-nicoyip.dev@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-11net/sched: act_ct: fix sk_buff leak when the header checks reject a packetHyunjung Ko1-4/+25
tcf_ct_handle_fragments() runs its header sanity checks before handing anything to the defragmentation engine: if (family == NFPROTO_IPV4) err = tcf_ct_ipv4_is_fragment(skb, &frag); else err = tcf_ct_ipv6_is_fragment(skb, &frag); if (err || !frag) return err; tcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM; tcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of them frees or queues the skb, so on that path the caller still owns it. tcf_ct_act() however funnels every non-zero return into the ownership-transfer exit: err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); if (err) goto out_frag; ... out_frag: if (err != -EINPROGRESS) tcf_action_inc_drop_qstats(&c->common); return TC_ACT_CONSUMED; TC_ACT_CONSUMED means the action took ownership of the skb, so no caller frees it - sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for that verdict. The skb is therefore orphaned: one sk_buff plus its data buffer is leaked per malformed packet, unbounded. Note the drop counter is already incremented for these errors, so the statistics claim a drop that never happens. Three different ownership states reach out_frag: today - the skb may be queued by the defrag engine (-EINPROGRESS), already freed by nf_ct_handle_fragments(), or still owned by us. Tell the caller which of those it is, and free the packet ourselves in the last case, which restores the TC_ACT_SHOT behaviour that predated the Fixes: commit. Reproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6 header with nexthdr = 0 (hop-by-hop) and nothing after it, on a clsact ingress chain with "action ct". kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet; with this patch it reports none. Fixes: 3f14b377d01d ("net/sched: act_ct: fix skb leak and crash on ooo frags") Cc: stable@vger.kernel.org # v6.8+ Signed-off-by: Hyunjung Ko <hj351016@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260806101235.809370-1-hj351016@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-11tcp: fix icsk_ack.ato bitfield overflowJiayuan Chen2-4/+6
On cross-region connections we observed delayed ACKs suddenly turning into immediate ACKs plus a TCP_MAX_QUICKACKS burst, as if the connection had just received its first data segment. Commit 95b9a87c6a6b ("tcp: record last received ipv6 flowlabel") squeezed icsk_ack.ato into 8 bits, sized for TCP_DELACK_MAX. But both writers still bound ato by icsk_rto, which can be well above 255 jiffies, so the bitfield assignment silently wraps mod 256: repeated delack timer misses double ato up to icsk_rto, storing 320 as 64 and 256 as 0, and ato == 0 is the "first data packet" sentinel in tcp_event_data_recv(). Clamp both writers to TCP_DELACK_MAX, which the static_assert already guarantees to fit and tcp_send_delayed_ack() effectively caps ato at anyway. Fixes: 95b9a87c6a6b ("tcp: record last received ipv6 flowlabel") Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20260807014437.36687-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-11net/sched: act_gact, act_police: range check the fallback control actionHyunjung Ko2-0/+11
tcf_action_check_ctrlact() range checks the primary control action: if (!opcode) ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0; TC_ACT_VALUE_MAX is TC_ACT_TRAP, so kernel-internal verdicts above it cannot be set that way. But act_gact and act_police each carry a second, independent control action supplied by user space that never reaches that helper - TCA_GACT_PROB.paction and TCA_POLICE_RESULT. Both only reject TC_ACT_GOTO_CHAIN, so any other value is stored verbatim and returned verbatim from the action. In particular user space can store TC_ACT_CONSUMED, which is TC_ACT_VALUE_MAX + 1 and is deliberately not part of the UAPI value range. That verdict tells every caller the action took ownership of the skb, so nobody frees it: sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for it. The result is one leaked sk_buff plus its data buffer per packet traversing the filter, unbounded, for all traffic on the chain including kernel-generated packets. Both are trivially deterministic. act_gact clamps tcfg_pval to >= 1, so with pval = 1 gact_determ() returns the fallback for every packet. act_police has no mandatory rate, so rate = 0 leaves tcfp_mtu = ~0 and tcf_police_mtu_check() always passes. TC_ACT_CONSUMED was added by commit 720f22fed81b ("net: sched: refactor reinsert action"), after both goto-chain guards were written: commit 9469f375ab09 ("net/sched: act_gact: disallow 'goto chain' on fallback control action") and commit c08f5ed5d625 ("net/sched: act_police: disallow 'goto chain' on fallback control action"). Neither guard was widened when the new verdict appeared. Factor the existing range test out of tcf_action_check_ctrlact() as tcf_action_valid() and apply it to both fallbacks. The helper cannot call tcf_action_check_ctrlact() directly because that also allocates a goto_chain, which is exactly what these two sites must not do. Reproduced on v7.2-rc6: kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet. With this patch both configurations are rejected with -EINVAL and kmemleak reports none. Fixes: 720f22fed81b ("net: sched: refactor reinsert action") Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Hyunjung Ko <hj351016@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Tested-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260806101252.809593-1-hj351016@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-11net: expect instance lock in netdev_queue_get_dma_dev()Jakub Kicinski1-1/+1
netdev_queue_get_dma_dev() uses "compat" locking assert which wants either the rtnl_lock or netdev instance lock. This is not right, the callers are taking the instance lock unconditionally. All entry points for queue config are purely instance locked. In other words the callers use netdev_get_by_index_lock(), not netdev_get_by_index_lock_ops_compat(). All the state we will access is effectively instance lock protected (it's const for devices which are not ops-locked). Update the assert to avoid false positive warnings. Cc: stable@vger.kernel.org Fixes: b6c5f9454ef34 ("io_uring/zcrx: call netdev_queue_get_dma_dev() under instance lock") Reported-by: syzbot+a78926bdac2adb52dc0e@syzkaller.appspotmail.com Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260806225627.3998672-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10netfilter: ipset: let destroy callbacks adjust ext mem sizeFlorian Westphal2-3/+2
For bitmap this change makes no difference, because destructors are called synchronously. List type however calls them via call_rcu() so accounting decrement can happen after list_set_flush() set ext_size to 0. 'set->elements = 0' can be removed for the same reason in the list type case, it calls 'set->elements--' for each element. Fixes: 9e41f26a505c ("netfilter: ipset: Count non-static extension memory for userspace") Suggested-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: ipset: fix list type element drift bugFlorian Westphal1-2/+5
If list_set_uadd() calls list_set_replace() to swap an expired entry, the element count remains the same, therefore the increment must be elided. Fixes: 702b71e7c666 ("netfilter: ipset: Add element count to all set types header") Link: https://sashiko.dev/#/patchset/20260806101947.2802-1-fw%40strlen.de Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: flowtable: publish GC-visible tuple lastJérémy Jean1-3/+4
nf_flow_table_iterate() only treats original-direction tuple nodes as owning entries. Publishing the original node first lets GC observe and free a flow while flow_offload_add() is still inserting the reply node. Publish the reply node first and the original node last so GC never sees a partially installed flow. KASAN can trigger slab-use-after-free read and write reports in the flowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del, flow_offload_lookup, etc.). Fixes: ac2a66665e23 ("netfilter: add generic flow table infrastructure") Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Assisted-by: Codex:gpt-5 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort pathAlexey Velichayshiy1-1/+1
In nft_flow_rule_offload_abort(), WARN_ON_ONCE(err) is triggered on every error during rollback, including -ENOMEM. Memory allocation failures are expected under low-memory conditions and do not indicate a kernel bug. Trace for example: nft_flow_offload_chain() // FLOW_BLOCK_BIND nft_flow_block_chain() nft_chain_offload_cmd() nft_block_offload_cmd() ->ndo_setup_tc() nsim_setup_tc() flow_block_cb_setup_simple() flow_block_cb_alloc() // fails to -ENOMEM The warning was reproduced on the 5.10 stable kernel under memory pressure via fault injection, but the underlying bug exists in mainline as well, as demonstrated by the ENOMEM trace above. The following splat was triggered during nf_tables transaction processing: WARNING: CPU: 0 PID: 8567 at net/netfilter/nf_tables_offload.c:532 nft_flow_rule_offload_abort net/netfilter/nf_tables_offload.c:532 [inline] WARNING: CPU: 0 PID: 8567 at net/netfilter/nf_tables_offload.c:532 nft_flow_rule_offload_commit+0x971/0xcd0 net/netfilter/nf_tables_offload.c:591 Modules linked in: CPU: 0 PID: 8567 Comm: syz-executor.0 Not tainted 5.10.260-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:nft_flow_rule_offload_abort net/netfilter/nf_tables_offload.c:532 [inline] RIP: 0010:nft_flow_rule_offload_commit+0x971/0xcd0 net/netfilter/nf_tables_offload.c:591 Call Trace: nf_tables_commit+0x3bd/0x4bd0 net/netfilter/nf_tables_api.c:8604 nfnetlink_rcv_batch+0xb1e/0x1f20 net/netfilter/nfnetlink.c:509 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:579 [inline] nfnetlink_rcv+0x3b3/0x420 net/netfilter/nfnetlink.c:597 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x6cd/0xa00 net/netfilter/af_netlink.c:1340 netlink_sendmsg+0x906/0xe10 net/netfilter/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] __sock_sendmsg+0x155/0x190 net/socket.c:663 ____sys_sendmsg+0x705/0x870 net/socket.c:2379 ___sys_sendmsg+0x100/0x170 net/socket.c:2433 __sys_sendmsg+0xe9/0x1c0 net/socket.c:2462 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Change the condition to WARN_ON_ONCE(err && err != -ENOMEM) so that warnings are only emitted for unexpected errors. This aligns with the common kernel practice of not warning on -ENOMEM. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 63b48c73ff56 ("netfilter: nf_tables_offload: undo updates if transaction fails") Signed-off-by: Alexey Velichayshiy <a.velichayshiy@ispras.ru> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: revalidate ihl to prevent out-of-bounds accessJulian Anastasov2-3/+11
While the outer IP header is already pulled into the skb head, we must be careful and revalidate the embedded headers after reading them from the skb frags to prevent out-of-bounds access. One such place reported by Sashiko is ip_vs_nat_icmp() where local process can change the ihl field and after skb_ensure_writable() we can see larger value which is a problem for the ip_send_check(cih) calls. Add check to drop the packet if the ihl field is changed. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Link: https://sashiko.dev/#/patchset/20260730183506.87473-1-ja%40ssi.bg Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: clear IPv4 options after rebasing tunnel ICMP errorsKyle Zeng1-0/+1
ip_vs_in_icmp() rebases an skb from the outer ICMP packet to the quoted original request before passing it to icmp_send(). However, IPCB(skb)->opt still describes the outer IPv4 header. A timestamp option in the outer header can therefore leave an offset that points into the quoted transport header after the rebase. __ip_options_echo() treats a byte at that stale location as the option length and copies it into the fixed-size option storage on the __icmp_send() stack, causing a stack out-of-bounds write. Clear the stale option metadata after resetting the network header. Keep the remaining control block fields, including the ingress interface used by the ICMP response path. Fixes: f2edb9f7706d ("ipvs: implement passive PMTUD for IPIP packets") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5.6-sol Codex:gpt-5.5-cyber Signed-off-by: Kyle Zeng <kylebot@openai.com> Co-developed-by: David Lee <david.lee@trailofbits.com> Signed-off-by: David Lee <david.lee@trailofbits.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet stateFlorian Westphal2-6/+11
sashiko reports: "nfnl_log_net_exit() calls nf_log_unset(), which clears the logger pointer without an RCU grace period. Immediately after, ops_free_list() frees the per-net state while concurrent packets might still be executing nf_log_packet() under rcu_read_lock()." Clear the pointer via .pre_exit to make sure rcu readers have completed before pernet storage is free'd. The change in nf_log_syslog.c is only done for consistency: it doesn't use pernet data. Link: https://sashiko.dev/#/patchset/20260731151806.849724-1-pablo%40netfilter.org Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nf_conntrack: defer invalid log until after unlockZihan Xi3-48/+102
TCP and SCTP conntrack paths can emit invalid-packet logs while ct->lock is still held. When invalid logging is routed to nfnetlink_log and conntrack export is enabled, the log path can re-enter conntrack netlink glue and dump the same conntrack again. Protocol attribute dumping may take ct->lock, so logging while holding that lock can deadlock. Defer the TCP invalid logs by storing only the minimal log context while ct->lock is held and emitting the log after unlocking. Also make the TCP timeout-lowering invalid path return whether a log is needed, then emit that log after unlocking. Do the same for the SCTP invalid state-transition log that can be reached while ct->lock is held. Add a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers that log invalid conntracks while holding ct->lock are caught outside TCP and SCTP as well. Fixes: 628d694344a0 ("netfilter: conntrack: reduce timeout when receiving out-of-window fin or rst") Fixes: d9a6f0d0df18 ("netfilter: conntrack: prepare tcp_in_window for ternary return value") Fixes: f71cb8f45d09 ("netfilter: conntrack: sctp: use nf log infrastructure for invalid packets") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Assisted-by: Codex:gpt-5.4 Signed-off-by: Zihan Xi <zihanx@nebusec.ai> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: separate destination availability stateYizhou Zhao7-16/+16
IPVS configuration paths update destination availability while connection accounting updates destination overload state. The two independent states share dest->flags, so their read-modify-write updates can race and lose one another. Keep OVERLOAD in flags, where the preceding patch serializes its updates with dst_lock, and move AVAILABLE to cflags. This keeps configuration- controlled availability out of the scheduler hot cacheline until a scheduler needs to check it. It also prevents availability updates from clobbering overload state. The destination status bits are not exposed through the IPVS sockopt or netlink interfaces, so keep their definitions in the internal IPVS header. Readers can still observe stale destination state; this does not provide a cross-field snapshot. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Reported-by: Ao Wang <wangao@seu.edu.cn> Reported-by: Xuewei Feng <fengxw06@126.com> Reported-by: Qi Li <qli01@tsinghua.edu.cn> Reported-by: Ke Xu <xuke@tsinghua.edu.cn> Link: https://lore.kernel.org/all/8913381c-1e02-35c7-0ec4-61de5a12fd35@ssi.bg/ Assisted-by: Claude-Code:GLM-5.2 Suggested-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: properly update the overload flag on dest editJulian Anastasov2-25/+69
The upper/lower connection thresholds for dest can be changed, so use ip_vs_dest_update_overload() to properly update the dest overload flag. The thresholds were not limited, fit them in the 0 .. INT_MAX range as already done in ipvsadm. As the thresholds are also read when connections are created and expired, use WRITE_ONCE/READ_ONCE to access them. As the lower threshold is optional, use (u - (u >> 2)) to calculate the 75% default value based on the upper threshold by preserving the integer rounding, as suggested by Yizhou Zhao. Trigger flag update when totalconns reaches one of the thresholds and use dst_lock to serialize the updating. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>