[PATCH 3.16.y-ckt 111/168] net/ping: handle protocol mismatching scenario

From: Luis Henriques
Date: Mon Dec 15 2014 - 09:42:42 EST


3.16.7-ckt3 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Jane Zhou <a17711@xxxxxxxxxxxx>

commit 91a0b603469069cdcce4d572b7525ffc9fd352a6 upstream.

ping_lookup() may return a wrong sock if sk_buff's and sock's protocols
dont' match. For example, sk_buff's protocol is ETH_P_IPV6, but sock's
sk_family is AF_INET, in that case, if sk->sk_bound_dev_if is zero, a wrong
sock will be returned.
the fix is to "continue" the searching, if no matching, return NULL.

Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Alexey Kuznetsov <kuznet@xxxxxxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: Hideaki YOSHIFUJI <yoshfuji@xxxxxxxxxxxxxx>
Cc: Patrick McHardy <kaber@xxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Jane Zhou <a17711@xxxxxxxxxxxx>
Signed-off-by: Yiwei Zhao <gbjc64@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
net/ipv4/ping.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 044a0ddf6a79..620e8ffa62e8 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -217,6 +217,8 @@ static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
&ipv6_hdr(skb)->daddr))
continue;
#endif
+ } else {
+ continue;
}

if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
--
2.1.3

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