netdev - [PATCH net-next 2/5] inet: ip_skb_dst_mtu() should use sk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1444018091-21987-3-git-send-email-edumazet@google.com>
Date:	Sun,  4 Oct 2015 21:08:08 -0700
From:	Eric Dumazet <edumazet@...gle.com>
To:	"David S . Miller" <davem@...emloft.net>
Cc:	netdev <netdev@...r.kernel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Eric Dumazet <eric.dumazet@...il.com>
Subject: [PATCH net-next 2/5] inet: ip_skb_dst_mtu() should use sk_fullsock()

SYN_RECV & TIMEWAIT sockets are not full blown,
do not even try to call ip_sk_use_pmtu() on them.

Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 include/net/ip.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/net/ip.h b/include/net/ip.h
index 91a6b2c88341..aa7811993276 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -323,12 +323,15 @@ static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
 
 static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
 {
-	if (!skb->sk || ip_sk_use_pmtu(skb->sk)) {
+	struct sock *sk = skb->sk;
+
+	if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) {
 		bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
+
 		return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
-	} else {
-		return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
 	}
+
+	return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
 }
 
 u32 ip_idents_reserve(u32 hash, int segs);
-- 
2.6.0.rc2.230.g3dd15c0

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html