From 8431c602f551549f082bbfa67f3003f2d8e3e132 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 11 Mar 2026 12:31:10 +0000 Subject: ip_tunnel: adapt iptunnel_xmit_stats() to NETDEV_PCPU_STAT_DSTATS Blamed commits forgot that vxlan/geneve use udp_tunnel[6]_xmit_skb() which call iptunnel_xmit_stats(). iptunnel_xmit_stats() was assuming tunnels were only using NETDEV_PCPU_STAT_TSTATS. @syncp offset in pcpu_sw_netstats and pcpu_dstats is different. 32bit kernels would either have corruptions or freezes if the syncp sequence was overwritten. This patch also moves pcpu_stat_type closer to dev->{t,d}stats to avoid a potential cache line miss since iptunnel_xmit_stats() needs to read it. Fixes: 6fa6de302246 ("geneve: Handle stats using NETDEV_PCPU_STAT_DSTATS.") Fixes: be226352e8dc ("vxlan: Handle stats using NETDEV_PCPU_STAT_DSTATS.") Signed-off-by: Eric Dumazet Reviewed-by: Guillaume Nault Link: https://patch.msgid.link/20260311123110.1471930-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/ip_tunnels.h | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) (limited to 'include/net') diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index 80662f812080..1f577a4f8ce9 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -665,13 +665,29 @@ static inline int iptunnel_pull_offloads(struct sk_buff *skb) static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len) { if (pkt_len > 0) { - struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats); - - u64_stats_update_begin(&tstats->syncp); - u64_stats_add(&tstats->tx_bytes, pkt_len); - u64_stats_inc(&tstats->tx_packets); - u64_stats_update_end(&tstats->syncp); - put_cpu_ptr(tstats); + if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) { + struct pcpu_dstats *dstats = get_cpu_ptr(dev->dstats); + + u64_stats_update_begin(&dstats->syncp); + u64_stats_add(&dstats->tx_bytes, pkt_len); + u64_stats_inc(&dstats->tx_packets); + u64_stats_update_end(&dstats->syncp); + put_cpu_ptr(dstats); + return; + } + if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) { + struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats); + + u64_stats_update_begin(&tstats->syncp); + u64_stats_add(&tstats->tx_bytes, pkt_len); + u64_stats_inc(&tstats->tx_packets); + u64_stats_update_end(&tstats->syncp); + put_cpu_ptr(tstats); + return; + } + pr_err_once("iptunnel_xmit_stats pcpu_stat_type=%d\n", + dev->pcpu_stat_type); + WARN_ON_ONCE(1); return; } -- 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 'include/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 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 'include/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 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 'include/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 'include/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 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 'include/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 b3a6df291fecf5f8a308953b65ca72b7fc9e015d Mon Sep 17 00:00:00 2001 From: Xiang Mei Date: Mon, 16 Mar 2026 18:02:41 -0700 Subject: udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n When CONFIG_IPV6 is disabled, the udp_sock_create6() function returns 0 (success) without actually creating a socket. Callers such as fou_create() then proceed to dereference the uninitialized socket pointer, resulting in a NULL pointer dereference. The captured NULL deref crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 RIP: 0010:fou_nl_add_doit (net/ipv4/fou_core.c:590 net/ipv4/fou_core.c:764) [...] Call Trace: genl_family_rcv_msg_doit.constprop.0 (net/netlink/genetlink.c:1114) genl_rcv_msg (net/netlink/genetlink.c:1194 net/netlink/genetlink.c:1209) [...] netlink_rcv_skb (net/netlink/af_netlink.c:2550) genl_rcv (net/netlink/genetlink.c:1219) netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1894) __sock_sendmsg (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1)) __sys_sendto (./include/linux/file.h:62 (discriminator 1) ./include/linux/file.h:83 (discriminator 1) net/socket.c:2183 (discriminator 1)) __x64_sys_sendto (net/socket.c:2213 (discriminator 1) net/socket.c:2209 (discriminator 1) net/socket.c:2209 (discriminator 1)) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (net/arch/x86/entry/entry_64.S:130) This patch makes udp_sock_create6 return -EPFNOSUPPORT instead, so callers correctly take their error paths. There is only one caller of the vulnerable function and only privileged users can trigger it. Fixes: fd384412e199b ("udp_tunnel: Seperate ipv6 functions into its own file.") Reported-by: Weiming Shi Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260317010241.1893893-1-xmei5@asu.edu Signed-off-by: Jakub Kicinski --- include/net/udp_tunnel.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h index d9c6d04bb3b5..fc1fc43345b5 100644 --- a/include/net/udp_tunnel.h +++ b/include/net/udp_tunnel.h @@ -52,7 +52,7 @@ int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg, static inline int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg, struct socket **sockp) { - return 0; + return -EPFNOSUPPORT; } #endif -- cgit v1.2.3