gro: Fix illegal merging of trailer trash
commitffa495ef3bad15580cfa8c119d15fe0227ee629c
authorHerbert Xu <herbert@gondor.apana.org.au>
Tue, 17 Nov 2009 13:18:18 +0000 (17 05:18 -0800)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 18 Dec 2009 21:43:53 +0000 (18 13:43 -0800)
tree03c9b7067a2f3e966f5abeab7cbbf6ab541911c9
parent88f921f674f5cca15fb550003d2d6cb83450e262
gro: Fix illegal merging of trailer trash

[ Upstream commit 69c0cab120a85471054614418b447349caba22d7 ]

When we've merged skb's with page frags, and subsequently receive
a trailer skb (< MSS) that is not completely non-linear (this can
occur on Intel NICs if the packet size falls below the threshold),
GRO ends up producing an illegal GSO skb with a frag_list.

This is harmless unless the skb is then forwarded through an
interface that requires software GSO, whereupon the GSO code
will BUG.

This patch detects this case in GRO and avoids merging the
trailer skb.

Reported-by: Mark Wagner <mwagner@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
net/core/skbuff.c