From: Hangbin Liu <liuhangbin@gmail.com> stable inclusion from stable-v5.10.113 commit 8fb76adb89f0d576c107e05fd922bf3d04c470d9 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 29e8e659f984be00d75ec5fef4e37c88def72712 ] packet_sock xmit could be dev_queue_xmit, which also returns negative errors. So only checking positive errors is not enough, or userspace sendmsg may return success while packet is not send out. Move the net_xmit_errno() assignment in the braces as checkpatch.pl said do not use assignment in if condition. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- net/packet/af_packet.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index d0c95d7dd292..5ee600d108a0 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2817,8 +2817,9 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) status = TP_STATUS_SEND_REQUEST; err = po->xmit(skb); - if (unlikely(err > 0)) { - err = net_xmit_errno(err); + if (unlikely(err != 0)) { + if (err > 0) + err = net_xmit_errno(err); if (err && __packet_get_status(po, ph) == TP_STATUS_AVAILABLE) { /* skb was destructed already */ @@ -3019,8 +3020,12 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) skb->no_fcs = 1; err = po->xmit(skb); - if (err > 0 && (err = net_xmit_errno(err)) != 0) - goto out_unlock; + if (unlikely(err != 0)) { + if (err > 0) + err = net_xmit_errno(err); + if (err) + goto out_unlock; + } dev_put(dev); -- 2.20.1