Patchwork [lucid/fsl-imx51,CVE,1/2] gro: Reset dev pointer on reuse

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Submitter Andy Whitcroft
Date July 27, 2011, 3:20 p.m.
Message ID <1311780055-21853-2-git-send-email-apw@canonical.com>
Download mbox | patch
Permalink /patch/107109/
State New
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Comments

Andy Whitcroft - July 27, 2011, 3:20 p.m.
From: Herbert Xu <herbert@gondor.apana.org.au>

commit 66c46d741e2e60f0e8b625b80edb0ab820c46d7a upstream.

On older kernels the VLAN code may zero skb->dev before dropping
it and causing it to be reused by GRO.

Unfortunately we didn't reset skb->dev in that case which causes
the next GRO user to get a bogus skb->dev pointer.

This particular problem no longer happens with the current upstream
kernel due to changes in VLAN processing.

However, for correctness we should still reset the skb->dev pointer
in the GRO reuse function in case a future user does the same thing.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

CVE-2011-1478
BugLink: http://bugs.launchpad.net/bugs/816549
Signed-off-by: Andy Whitcroft <apw@canonical.com>
---
 net/core/dev.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

Patch

diff --git a/net/core/dev.c b/net/core/dev.c
index 4225097..bed9dc3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2557,6 +2557,7 @@  void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
 {
 	__skb_pull(skb, skb_headlen(skb));
 	skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb));
+	skb->dev = napi->dev;
 
 	napi->skb = skb;
 }