From: xu xin <xu.xin16@xxxxxxxxxx> [ Upstream commit c67180efc507e04a87f22aa68bd7dd832db006b7 ] For now, No matter what error pointer ip_neigh_for_gw() returns, ip_finish_output2() always return -EINVAL, which may mislead the upper users. For exemple, an application uses sendto to send an UDP packet, but when the neighbor table overflows, sendto() will get a value of -EINVAL, and it will cause users to waste a lot of time checking parameters for errors. Return the real errno instead of -EINVAL. Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx> Reviewed-by: Yang Yang <yang.yang29@xxxxxxxxxx> Cc: Si Hao <si.hao@xxxxxxxxxx> Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@xxxxxxxxx> Link: https://lore.kernel.org/r/20230807015408.248237-1-xu.xin16@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ipv4/ip_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 6f6f63cf9224f..f649a65bfefa7 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -236,7 +236,7 @@ static int ip_finish_output2(struct net *net, struct sock *sk, struct sk_buff *s net_dbg_ratelimited("%s: No header cache and no neighbour!\n", __func__); kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_CREATEFAIL); - return -EINVAL; + return PTR_ERR(neigh); } static int ip_finish_output_gso(struct net *net, struct sock *sk, -- 2.40.1
