From 29ffe1a5c52dae13b6efead97aab9b058f38fce4 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 28 Jan 2008 20:45:20 -0800 Subject: [INET]: Prevent out-of-sync truesize on ip_fragment slow path When ip_fragment has to hit the slow path the value of skb->truesize may go out of sync because we would have updated it without changing the packet length. This violates the constraints on truesize. This patch postpones the update of skb->truesize to prevent this. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/ip6_output.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net/ipv6/ip6_output.c') diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 15c4f6c..cfe9e70 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -636,6 +636,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) if (skb_shinfo(skb)->frag_list) { int first_len = skb_pagelen(skb); + int truesizes = 0; if (first_len - hlen > mtu || ((first_len - hlen) & 7) || @@ -658,7 +659,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) sock_hold(skb->sk); frag->sk = skb->sk; frag->destructor = sock_wfree; - skb->truesize -= frag->truesize; + truesizes += frag->truesize; } } @@ -689,6 +690,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) first_len = skb_pagelen(skb); skb->data_len = first_len - skb_headlen(skb); + skb->truesize -= truesizes; skb->len = first_len; ipv6_hdr(skb)->payload_len = htons(first_len - sizeof(struct ipv6hdr)); -- cgit v1.1