linux-kernel - [PATCH] fs/gfs2: Use an IS_ERR test rather than a NULL test

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 1 Sep 2008 10:51:22 +0200
From:	Julien Brunel <brunel@...u.dk>
To:	swhiteho@...hat.com, cluster-devel@...hat.com,
	linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: [PATCH] fs/gfs2: Use an IS_ERR test rather than a NULL test

From: Julien Brunel <brunel@...u.dk>

In case of error, the function gfs2_inode_lookup returns an
ERR pointer, but never returns a NULL pointer. So a NULL test that
necessarily comes after an IS_ERR test should be deleted, and a NULL
test that may come after a call to this function should be
strengthened by an IS_ERR test.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@match_bad_null_test@
expression x, E;
statement S1,S2;
@@
x = gfs2_inode_lookup(...)
... when != x = E
* if (x != NULL) 
S1 else S2
// </smpl>

Signed-off-by:  Julien Brunel <brunel@...u.dk>
Signed-off-by:  Julia Lawall <julia@...u.dk>

---
 fs/gfs2/inode.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff -u -p a/fs/gfs2/inode.c b/fs/gfs2/inode.c
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1033,13 +1033,11 @@ struct inode *gfs2_createi(struct gfs2_h
 
 	if (bh)
 		brelse(bh);
-	if (!inode)
-		return ERR_PTR(-ENOMEM);
 	return inode;
 
 fail_gunlock2:
 	gfs2_glock_dq_uninit(ghs + 1);
-	if (inode)
+	if (inode && !IS_ERR(inode))
 		iput(inode);
 fail_gunlock:
 	gfs2_glock_dq(ghs);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/