diff options
| author | Eric Dumazet <edumazet@google.com> | 2026-01-21 16:37:24 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-01-30 12:27:38 +0300 |
| commit | 03710cebfc0bcfe247a9e04381e79ea33896e278 (patch) | |
| tree | e05cd3c031b8ae451e0d80c9e3b2c49605c2a7c1 | |
| parent | d9d5f222558b42f6277eafaaa6080966faf37676 (diff) | |
| download | linux-03710cebfc0bcfe247a9e04381e79ea33896e278.tar.xz | |
net/sched: act_ife: avoid possible NULL deref
[ Upstream commit 27880b0b0d35ad1c98863d09788254e36f874968 ]
tcf_ife_encode() must make sure ife_encode() does not return NULL.
syzbot reported:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:ife_tlv_meta_encode+0x41/0xa0 net/ife/ife.c:166
CPU: 3 UID: 0 PID: 8990 Comm: syz.0.696 Not tainted syzkaller #0 PREEMPT(full)
Call Trace:
<TASK>
ife_encode_meta_u32+0x153/0x180 net/sched/act_ife.c:101
tcf_ife_encode net/sched/act_ife.c:841 [inline]
tcf_ife_act+0x1022/0x1de0 net/sched/act_ife.c:877
tc_act include/net/tc_wrapper.h:130 [inline]
tcf_action_exec+0x1c0/0xa20 net/sched/act_api.c:1152
tcf_exts_exec include/net/pkt_cls.h:349 [inline]
mall_classify+0x1a0/0x2a0 net/sched/cls_matchall.c:42
tc_classify include/net/tc_wrapper.h:197 [inline]
__tcf_classify net/sched/cls_api.c:1764 [inline]
tcf_classify+0x7f2/0x1380 net/sched/cls_api.c:1860
multiq_classify net/sched/sch_multiq.c:39 [inline]
multiq_enqueue+0xe0/0x510 net/sched/sch_multiq.c:66
dev_qdisc_enqueue+0x45/0x250 net/core/dev.c:4147
__dev_xmit_skb net/core/dev.c:4262 [inline]
__dev_queue_xmit+0x2998/0x46c0 net/core/dev.c:4798
Fixes: 295a6e06d21e ("net/sched: act_ife: Change to use ife module")
Reported-by: syzbot+5cf914f193dffde3bd3c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6970d61d.050a0220.706b.0010.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yotam Gigi <yotam.gi@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260121133724.3400020-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/sched/act_ife.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c index 431921204f66..567a58d30df8 100644 --- a/net/sched/act_ife.c +++ b/net/sched/act_ife.c @@ -821,6 +821,7 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, /* could be stupid policy setup or mtu config * so lets be conservative.. */ if ((action == TC_ACT_SHOT) || exceed_mtu) { +drop: qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); return TC_ACT_SHOT; } @@ -829,6 +830,8 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, skb_push(skb, skb->dev->hard_header_len); ife_meta = ife_encode(skb, metalen); + if (!ife_meta) + goto drop; spin_lock(&ife->tcf_lock); @@ -844,8 +847,7 @@ static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, if (err < 0) { /* too corrupt to keep around if overwritten */ spin_unlock(&ife->tcf_lock); - qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); - return TC_ACT_SHOT; + goto drop; } skboff += err; } |