From: Greg KH on
2.6.32-stable review patch. If anyone has any objections, please let us know.

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

From: Christian Lamparter <chunkeey(a)googlemail.com>

commit f5300e04df78feae8107c1846dd3a9e27c071b2f upstream.

A long time ago, a user reported several crashes due to
data corruptions which are likely the result of a
not-100%-supported, or faulty? PCI bridge.
( http://patchwork.kernel.org/patch/53004/ )

This patch fixes entry #1.
"1. p54p_check_rx_ring - skb_over_panic: Under a ping flood
or just left running for a bit would panic with a skb_over_panic."
As described in the mail: The invalid frame length causes
skb_put to bailout and trigger a crash.

Note:
Simply dropping the frame is problematic, because if its content
contains a tx feedback we would lose some portion of the device
memory space.... And the driver/mac80211 should handle all other
invalid data.

Reported-by: Quintin Pitts <geek4linux(a)gmail.com>
Signed-off-by: Christian Lamparter <chunkeey(a)googlemail.com>
Signed-off-by: John W. Linville <linville(a)tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>

---
drivers/net/wireless/p54/p54pci.c | 8 ++++++++
1 file changed, 8 insertions(+)

--- a/drivers/net/wireless/p54/p54pci.c
+++ b/drivers/net/wireless/p54/p54pci.c
@@ -205,6 +205,14 @@ static void p54p_check_rx_ring(struct ie
i %= ring_limit;
continue;
}
+
+ if (unlikely(len > priv->common.rx_mtu)) {
+ if (net_ratelimit())
+ dev_err(&priv->pdev->dev, "rx'd frame size "
+ "exceeds length threshold.\n");
+
+ len = priv->common.rx_mtu;
+ }
skb_put(skb, len);

if (p54_rx(dev, skb)) {


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