kernel/linux.git/include/net/tc_act, branch v6.18.48

net/sched: act_pedit: fix TOCTOU heap OOB write in tc offload

2026-07-24T14:16:47+00:00

[ Upstream commit 8b519cbcabe836a441369fbec1a8a6518a709251 ] There is a TOCTOU race condition in flower lockless approach between sizing a flow_rule buffer and filling it. zdi-disclosures@trendmicro.com reports: The cls_flower classifier operates with TCF_PROTO_OPS_DOIT_UNLOCKED (fl_change runs without RTNL), while RTM_NEWACTION holds RTNL, so the independent locking domains make the race reachable in practice. KASAN confirms: BUG: KASAN: slab-out-of-bounds in tcf_pedit_offload_act_setup+0x81b/0x930 Write of size 4 at addr ffff888001f27520 by task poc-toctou/312 The buggy address is located 0 bytes to the right of allocated 288-byte region [ffff888001f27400, ffff888001f27520) (cache kmalloc-512) Note: The result is a heap OOB write attacker-controlled content into the adjacent slab object (requires CAP_NET_ADMIN). The fix introduces reading tcfp_nkeys under act->tcfa_lock in all places using a new tcf_pedit_nkeys_locked() which replaces the old tcf_pedit_nkeys(). Additionally we close the remaining TOCTOU window between the sizing read and the fill reads by more careful accounting. Rather than silently truncating the key count, which leads to incorrect action semantics offloaded to hardware and secondary OOB writes if the remaining capacity is zero or consumed by prior actions, we enforce remaining capacity checks and return -ENOSPC if the required space exceeds the remaining capacity. Fixes: 71d0ed7079df ("net/act_pedit: Support using offset relative to the conventional network headers") Reported-by: zdi-disclosures@trendmicro.com Tested-by: Victor Nogueira Signed-off-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260701161912.125355-1-jhs@mojatatu.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net/sched: fix pedit partial COW leading to page cache corruption

2026-06-19T11:43:55+00:00

[ Upstream commit 899ee91156e57784090c5565e4f31bd7dbffbc5a ] tcf_pedit_act() computes the COW range for skb_ensure_writable() once before the key loop using tcfp_off_max_hint, but the hint does not account for the runtime header offset added by typed keys. This can leave part of the write region un-COW'd. Fix by moving skb_ensure_writable() inside the per-key loop where the actual write offset is known, and add overflow checking on the offset arithmetic. For negative offsets (e.g. Ethernet header edits at ingress), use skb_cow() to COW the headroom instead. Guard offset_valid() against INT_MIN, where negation is undefined. Fixes: 8b796475fd78 ("net/sched: act_pedit: really ensure the skb is writable") Reported-by: Yiming Qian Reported-by: Keenan Dong Reported-by: Han Guidong <2045gemini@gmail.com> Reported-by: Zhang Cen Reviewed-by: Han Guidong <2045gemini@gmail.com> Tested-by: Han Guidong <2045gemini@gmail.com> Reviewed-by: Davide Caratti Tested-by: Davide Caratti Reviewed-by: Toke Høiland-Jørgensen Tested-by: Toke Høiland-Jørgensen Reviewed-by: Victor Nogueira Tested-by: Victor Nogueira Acked-by: Jamal Hadi Salim Signed-off-by: Rajat Gupta Link: https://patch.msgid.link/20260531123221.48732-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: act_gate: snapshot parameters with RCU on replace

2026-03-13T16:23:28+00:00

commit 62413a9c3cb183afb9bb6e94dd68caf4e4145f4c upstream. The gate action can be replaced while the hrtimer callback or dump path is walking the schedule list. Convert the parameters to an RCU-protected snapshot and swap updates under tcf_lock, freeing the previous snapshot via call_rcu(). When REPLACE omits the entry list, preserve the existing schedule so the effective state is unchanged. Fixes: a51c328df310 ("net: qos: introduce a gate control flow action") Cc: stable@vger.kernel.org Signed-off-by: Paul Moses Tested-by: Vladimir Oltean Acked-by: Jamal Hadi Salim Reviewed-by: Victor Nogueira Link: https://patch.msgid.link/20260223150512.2251594-2-p@1g4.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net/sched: act_ife: Fix metalist update behavior

2026-03-12T11:10:01+00:00

[ Upstream commit e2cedd400c3ec0302ffca2490e8751772906ac23 ] Whenever an ife action replace changes the metalist, instead of replacing the old data on the metalist, the current ife code is appending the new metadata. Aside from being innapropriate behavior, this may lead to an unbounded addition of metadata to the metalist which might cause an out of bounds error when running the encode op: [ 138.423369][ C1] ================================================================== [ 138.424317][ C1] BUG: KASAN: slab-out-of-bounds in ife_tlv_meta_encode (net/ife/ife.c:168) [ 138.424906][ C1] Write of size 4 at addr ffff8880077f4ffe by task ife_out_out_bou/255 [ 138.425778][ C1] CPU: 1 UID: 0 PID: 255 Comm: ife_out_out_bou Not tainted 7.0.0-rc1-00169-gfbdfa8da05b6 #624 PREEMPT(full) [ 138.425795][ C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 138.425800][ C1] Call Trace: [ 138.425804][ C1] [ 138.425808][ C1] dump_stack_lvl (lib/dump_stack.c:122) [ 138.425828][ C1] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) [ 138.425839][ C1] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 138.425844][ C1] ? __virt_addr_valid (./arch/x86/include/asm/preempt.h:95 (discriminator 1) ./include/linux/rcupdate.h:975 (discriminator 1) ./include/linux/mmzone.h:2207 (discriminator 1) arch/x86/mm/physaddr.c:54 (discriminator 1)) [ 138.425853][ C1] ? ife_tlv_meta_encode (net/ife/ife.c:168) [ 138.425859][ C1] kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:597) [ 138.425868][ C1] ? ife_tlv_meta_encode (net/ife/ife.c:168) [ 138.425878][ C1] kasan_check_range (mm/kasan/generic.c:186 (discriminator 1) mm/kasan/generic.c:200 (discriminator 1)) [ 138.425884][ C1] __asan_memset (mm/kasan/shadow.c:84 (discriminator 2)) [ 138.425889][ C1] ife_tlv_meta_encode (net/ife/ife.c:168) [ 138.425893][ C1] ? ife_tlv_meta_encode (net/ife/ife.c:171) [ 138.425898][ C1] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 138.425903][ C1] ife_encode_meta_u16 (net/sched/act_ife.c:57) [ 138.425910][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) [ 138.425916][ C1] ? __asan_memcpy (mm/kasan/shadow.c:105 (discriminator 3)) [ 138.425921][ C1] ? __pfx_ife_encode_meta_u16 (net/sched/act_ife.c:45) [ 138.425927][ C1] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221) [ 138.425931][ C1] tcf_ife_act (net/sched/act_ife.c:847 net/sched/act_ife.c:879) To solve this issue, fix the replace behavior by adding the metalist to the ife rcu data structure. Fixes: aa9fd9a325d51 ("sched: act: ife: update parameters via rcu handling") Reported-by: Ruitong Liu Tested-by: Ruitong Liu Co-developed-by: Victor Nogueira Signed-off-by: Victor Nogueira Signed-off-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260304140603.76500-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net_sched: act_skbmod: use RCU in tcf_skbmod_dump()

2025-08-28T23:46:23+00:00

Also storing tcf_action into struct tcf_skbmod_params makes sure there is no discrepancy in tcf_skbmod_act(). No longer block BH in tcf_skbmod_init() when acquiring tcf_lock. Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250827125349.3505302-5-edumazet@google.com Signed-off-by: Jakub Kicinski

net_sched: act_tunnel_key: use RCU in tunnel_key_dump()

2025-08-28T23:46:23+00:00

Also storing tcf_action into struct tcf_tunnel_key_params makes sure there is no discrepancy in tunnel_key_act(). No longer block BH in tunnel_key_init() when acquiring tcf_lock. Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250827125349.3505302-4-edumazet@google.com Signed-off-by: Jakub Kicinski

net_sched: act_vlan: use RCU in tcf_vlan_dump()

2025-08-28T23:46:23+00:00

Also storing tcf_action into struct tcf_vlan_params makes sure there is no discrepancy in tcf_vlan_act(). No longer block BH in tcf_vlan_init() when acquiring tcf_lock. Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250827125349.3505302-3-edumazet@google.com Signed-off-by: Jakub Kicinski

net_sched: act_skbedit: use RCU in tcf_skbedit_dump()

2025-07-11T23:01:17+00:00

Also storing tcf_action into struct tcf_skbedit_params makes sure there is no discrepancy in tcf_skbedit_act(). Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20250709090204.797558-12-edumazet@google.com Signed-off-by: Jakub Kicinski

net_sched: act_police: use RCU in tcf_police_dump()

2025-07-11T23:01:17+00:00

Also storing tcf_action into struct tcf_police_params makes sure there is no discrepancy in tcf_police_act(). Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20250709090204.797558-11-edumazet@google.com Signed-off-by: Jakub Kicinski

net_sched: act_pedit: use RCU in tcf_pedit_dump()

2025-07-11T23:01:17+00:00

Also storing tcf_action into struct tcf_pedit_params makes sure there is no discrepancy in tcf_pedit_act(). Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20250709090204.797558-10-edumazet@google.com Signed-off-by: Jakub Kicinski