[34/59] net: Fix a memmove bug in dev_gro_receive()

From: Greg KH
Date: Tue Aug 24 2010 - 19:42:30 EST


2.6.32-stable review patch. If anyone has any objections, please let us know.

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


From: Jarek Poplawski <jarkao2@xxxxxxxxx>

[ Upstream commit e5093aec2e6b60c3df2420057ffab9ed4a6d2792 ]

>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@xxxxxxxxx>
Signed-off-by: Jarek Poplawski <jarkao2@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2519,7 +2519,7 @@ 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));
}
}



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/