From: Xi Wang <xi.wang@gmail.com>
Date: Fri, 4 Jan 2013 08:22:57 +0000 (-0500)
Subject: nfs: fix null checking in nfs_get_option_str()
X-Git-Tag: v3.4.25~38
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=042cf2fb1d2ac4b4b27b2ccc4ac317a2f53df3c3;p=platform%2Fkernel%2Flinux-stable.git

nfs: fix null checking in nfs_get_option_str()

commit e25fbe380c4e3c09afa98bcdcd9d3921443adab8 upstream.

The following null pointer check is broken.

	*option = match_strdup(args);
	return !option;

The pointer `option' must be non-null, and thus `!option' is always false.
Use `!*option' instead.

The bug was introduced in commit c5cb09b6f8 ("Cleanup: Factor out some
cut-and-paste code.").

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index feabe7a394c3..c252161e7b1d 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1138,7 +1138,7 @@ static int nfs_get_option_str(substring_t args[], char **option)
 {
 	kfree(*option);
 	*option = match_strdup(args);
-	return !option;
+	return !*option;
 }
 
 static int nfs_get_option_ul(substring_t args[], unsigned long *option)