From: Alexey Khoroshilov <khoroshilov@ispras.ru>
Date: Wed, 8 Aug 2012 00:33:25 +0000 (+0000)
Subject: net/core: Fix potential memory leak in dev_set_alias()
X-Git-Tag: v3.4.12~211
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=caf2630c41a183b72e5d6211e5efd1457ac0c463;p=platform%2Fkernel%2Flinux-stable.git

net/core: Fix potential memory leak in dev_set_alias()

[ Upstream commit 7364e445f62825758fa61195d237a5b8ecdd06ec ]

Do not leak memory by updating pointer with potentially NULL realloc return value.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/core/dev.c b/net/core/dev.c
index 665730f..a1e0355 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1056,6 +1056,8 @@ rollback:
  */
 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
 {
+	char *new_ifalias;
+
 	ASSERT_RTNL();
 
 	if (len >= IFALIASZ)
@@ -1069,9 +1071,10 @@ int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
 		return 0;
 	}
 
-	dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
-	if (!dev->ifalias)
+	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
+	if (!new_ifalias)
 		return -ENOMEM;
+	dev->ifalias = new_ifalias;
 
 	strlcpy(dev->ifalias, alias, len+1);
 	return len;