From 56035022d86fff45299288cb372a42f752ba23fa Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 5 Feb 2009 21:26:52 -0800 Subject: [PATCH] gro: Fix frag_list merging on imprecisely split packets The previous fix ad0f9904444de1309dedd2b9e365cae8af77d9b1 (gro: Fix handling of imprecisely split packets) only fixed the case of frags merging, frag_list merging in the same circumstances were still broken. In particular, the packet headers end up in the data stream. This patch fixes this plus another issue where an imprecisely split packet header may be read incorrectly (this is mostly harmless since it'll simply cause the packet to not match and be rejected for GRO). Thanks to Emil Tantilov and Jeff Kirsher for helping to track this down. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/core/dev.c | 3 ++- net/core/skbuff.c | 11 +++++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 3337cf9..247f161 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2391,7 +2391,8 @@ void *skb_gro_header(struct sk_buff *skb, unsigned int hlen) return pskb_may_pull(skb, hlen) ? skb->data + offset : NULL; return page_address(skb_shinfo(skb)->frags[0].page) + - skb_shinfo(skb)->frags[0].page_offset + offset; + skb_shinfo(skb)->frags[0].page_offset + + offset - skb_headlen(skb); } EXPORT_SYMBOL(skb_gro_header); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index e55d1ef..67f2a2f 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2678,6 +2678,17 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) p = nskb; merge: + if (skb_gro_offset(skb) > skb_headlen(skb)) { + skb_shinfo(skb)->frags[0].page_offset += + skb_gro_offset(skb) - skb_headlen(skb); + skb_shinfo(skb)->frags[0].size -= + skb_gro_offset(skb) - skb_headlen(skb); + skb_gro_reset_offset(skb); + skb_gro_pull(skb, skb_headlen(skb)); + } + + __skb_pull(skb, skb_gro_offset(skb)); + p->prev->next = skb; p->prev = skb; skb_header_release(skb); -- 1.8.2.3