6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> [ Upstream commit e400cfa38bb0419cf1313e5494ea2b7d114e86d7 ] Even if OOB data is recv()ed, ioctl(SIOCATMARK) must return 1 when the OOB skb is at the head of the receive queue and no new OOB data is queued. Without fix: # RUN msg_oob.no_peek.oob ... # msg_oob.c:305:oob:Expected answ[0] (0) == oob_head (1) # oob: Test terminated by assertion # FAIL msg_oob.no_peek.oob not ok 2 msg_oob.no_peek.oob With fix: # RUN msg_oob.no_peek.oob ... # OK msg_oob.no_peek.oob ok 2 msg_oob.no_peek.oob Fixes: 314001f0bf92 ("af_unix: Add OOB support") Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/unix/af_unix.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index e0fea73317de8..24286ce0ef3ee 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -3154,12 +3154,23 @@ static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) #if IS_ENABLED(CONFIG_AF_UNIX_OOB) case SIOCATMARK: { + struct unix_sock *u = unix_sk(sk); struct sk_buff *skb; int answ = 0; + mutex_lock(&u->iolock); + skb = skb_peek(&sk->sk_receive_queue); - if (skb && skb == READ_ONCE(unix_sk(sk)->oob_skb)) - answ = 1; + if (skb) { + struct sk_buff *oob_skb = READ_ONCE(u->oob_skb); + + if (skb == oob_skb || + (!oob_skb && !unix_skb_len(skb))) + answ = 1; + } + + mutex_unlock(&u->iolock); + err = put_user(answ, (int __user *)arg); } break; -- 2.43.0