diff options
| author | Ranganath V N <vnranganath.20@gmail.com> | 2025-10-26 22:03:12 +0530 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2025-10-30 11:21:05 +0100 |
| commit | 51e5ad549c43b557c7da1e4d1a1dcf061b4a5f6c (patch) | |
| tree | e62cff853ad04428f9f97a771096038d8eca1c3a | |
| parent | 6a2108c78069fda000729b88c97b1eba0405e6d7 (diff) | |
net: sctp: fix KMSAN uninit-value in sctp_inq_pop
Fix an issue detected by syzbot:
KMSAN reported an uninitialized-value access in sctp_inq_pop
BUG: KMSAN: uninit-value in sctp_inq_pop
The issue is actually caused by skb trimming via sk_filter() in sctp_rcv().
In the reproducer, skb->len becomes 1 after sk_filter(), which bypassed the
original check:
if (skb->len < sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr) +
skb_transport_offset(skb))
To handle this safely, a new check should be performed after sk_filter().
Reported-by: syzbot+d101e12bccd4095460e7@syzkaller.appspotmail.com
Tested-by: syzbot+d101e12bccd4095460e7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d101e12bccd4095460e7
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Suggested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Ranganath V N <vnranganath.20@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251026-kmsan_fix-v3-1-2634a409fa5f@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | net/sctp/input.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/sctp/input.c b/net/sctp/input.c index 7e99894778d4..e119e460ccde 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -190,7 +190,7 @@ int sctp_rcv(struct sk_buff *skb) goto discard_release; nf_reset_ct(skb); - if (sk_filter(sk, skb)) + if (sk_filter(sk, skb) || skb->len < sizeof(struct sctp_chunkhdr)) goto discard_release; /* Create an SCTP packet structure. */ |