Eric Dumazet f9f85ebad5 af_key: validate families in pfkey_send_migrate() ...

[ Upstream commit eb2d16a7d599dc9d4df391b5e660df9949963786 ]

syzbot was able to trigger a crash in skb_put() [1]

Issue is that pfkey_send_migrate() does not check old/new families,
and that set_ipsecrequest() @family argument was truncated,
thus possibly overfilling the skb.

Validate families early, do not wait set_ipsecrequest().

[1]

skbuff: skb_over_panic: text:ffffffff8a752120 len:392 put:16 head:ffff88802a4ad040 data:ffff88802a4ad040 tail:0x188 end:0x180 dev:<NULL>
 kernel BUG at net/core/skbuff.c:214 !
Call Trace:
 <TASK>
  skb_over_panic net/core/skbuff.c:219 [inline]
  skb_put+0x159/0x210 net/core/skbuff.c:2655
  skb_put_zero include/linux/skbuff.h:2788 [inline]
  set_ipsecrequest net/key/af_key.c:3532 [inline]
  pfkey_send_migrate+0x1270/0x2e50 net/key/af_key.c:3636
  km_migrate+0x155/0x260 net/xfrm/xfrm_state.c:2848
  xfrm_migrate+0x2140/0x2450 net/xfrm/xfrm_policy.c:4705
  xfrm_do_migrate+0x8ff/0xaa0 net/xfrm/xfrm_user.c:3150

Fixes: 08de61beab ("[PFKEYV2]: Extension for dynamic update of endpoint address(es)")
Reported-by: syzbot+b518dfc8e021988fbd55@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/69b5933c.050a0220.248e02.00f2.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>

2026-05-07 10:55:20 +02:00

..

af_key.c

af_key: validate families in pfkey_send_migrate()

2026-05-07 10:55:20 +02:00

Makefile

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