[PATCH 3.19 011/177] ipv4: ip_check_defrag should correctly check return value of skb_copy_bits

Greg Kroah-Hartman
2015-03-16T14:10:47Z

From: Alexander Drozdov <al.drozdov@gmail.com>

[ Upstream commit fba04a9e0c869498889b6445fd06cbe7da9bb834 ]

skb_copy_bits() returns zero on success and negative value on error,
so it is needed to invert the condition in ip_check_defrag().

Fixes: 1bf3751ec90c ("ipv4: ip_check_defrag must not modify skb before unsharing")
Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ipv4/ip_fragment.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -664,7 +664,7 @@ struct sk_buff *ip_check_defrag(struct s
if (skb->protocol != htons(ETH_P_IP))
return skb;

- if (!skb_copy_bits(skb, 0, &iph, sizeof(iph)))
+ if (skb_copy_bits(skb, 0, &iph, sizeof(iph)) < 0)
return skb;

if (iph.ihl < 5 || iph.version != 4)