net: Fix a memmove bug in dev_gro_receive()
authorJarek Poplawski <jarkao2@gmail.com>
Wed, 11 Aug 2010 02:02:10 +0000 (02:02 +0000)
committerDavid S. Miller <davem@davemloft.net>
Wed, 18 Aug 2010 00:37:28 +0000 (17:37 -0700)
>Xin Xiaohui wrote:
> I looked into the code dev_gro_receive(), found the code here:
> if the frags[0] is pulled to 0, then the page will be released,
> and memmove() frags left.
> Is that right? I'm not sure if memmove do right or not, but
> frags[0].size is never set after memove at least. what I think
> a simple way is not to do anything if we found frags[0].size == 0.
> The patch is as followed.
...

This version of the patch fixes the bug directly in memmove.

Reported-by: "Xin, Xiaohui" <xiaohui.xin@intel.com>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/dev.c

index 1ae6543..3721fbb 100644 (file)
@@ -3143,7 +3143,7 @@ pull:
                        put_page(skb_shinfo(skb)->frags[0].page);
                        memmove(skb_shinfo(skb)->frags,
                                skb_shinfo(skb)->frags + 1,
-                               --skb_shinfo(skb)->nr_frags);
+                               --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
                }
        }