From mboxrd@z Thu Jan  1 00:00:00 1970
From: Abraham Arce <abraham.arce.moreno@gmail.com>
Subject: KS8851: Possible NULL dereferenced in ks8851_rx_pkts
Date: Thu, 8 Apr 2010 02:03:57 -0500
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Hi,

These changes avoid a possible dereference in skb_reserve when skb is
NULL. I am increasing rx dropped packet count but not sure about how
to handle the dump of frames. Any advice is appreciated.

diff --git a/drivers/net/ks8851.c b/drivers/net/ks8851.c
index d6dc29b..a1aa757 100644
--- a/drivers/net/ks8851.c
+++ b/drivers/net/ks8851.c
@@ -534,8 +534,11 @@ static void ks8851_rx_pkts(struct ks8851_net *ks)

 		if (rxlen > 0) {
 			skb = netdev_alloc_skb(ks->netdev, rxlen + 2 + 8);
-			if (!skb) {
+			if (unlikely(!skb)) {
 				/* todo - dump frame and move on */
+				ks_dbg(ks, "No free memory, packet dropped\n");
+				ks->netdev->stats.rx_dropped++;
+				return;
 			}

 			/* two bytes to ensure ip is aligned, and four bytes

Best Regards
Abraham