From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Brivio Subject: [PATCH net] ipv4: Don't override return code from ip_route_input_noref() Date: Thu, 31 Aug 2017 18:11:41 +0200 Message-ID: Cc: Sabrina Dubroca , Wei Wang To: "David S . Miller" , netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:58380 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662AbdHaQMa (ORCPT ); Thu, 31 Aug 2017 12:12:30 -0400 Sender: netdev-owner@vger.kernel.org List-ID: After ip_route_input() calls ip_route_input_noref(), another check on skb_dst() is done, but if this fails, we shouldn't override the return code from ip_route_input_noref(), as it could have been more specific (i.e. -EHOSTUNREACH). This also saves one call to skb_dst_force_safe() and one to skb_dst() in case the ip_route_input_noref() check fails. Reported-by: Sabrina Dubroca Fixes: ad65a2f05695 ("ipv4: call dst_hold_safe() properly") Signed-off-by: Stefano Brivio --- include/net/route.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/include/net/route.h b/include/net/route.h index cb0a76d9dde1..1b09a9368c68 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -189,10 +189,11 @@ static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, rcu_read_lock(); err = ip_route_input_noref(skb, dst, src, tos, devin); - if (!err) + if (!err) { skb_dst_force_safe(skb); - if (!skb_dst(skb)) - err = -EINVAL; + if (!skb_dst(skb)) + err = -EINVAL; + } rcu_read_unlock(); return err; -- 2.9.4