From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from albert.telenet-ops.be ([2a02:1800:110:4::f00:1a]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dtchO-0005KN-Tk for linux-mtd@lists.infradead.org; Sun, 17 Sep 2017 16:45:43 +0000 From: Geert Uytterhoeven To: Richard Weinberger , Artem Bityutskiy , Adrian Hunter Cc: Hyunchul Lee , Colin Ian King , Dan Carpenter , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] ubifs: Fix uninitialized variable in search_dh_cookie() Date: Sun, 17 Sep 2017 10:32:20 +0200 Message-Id: <1505637141-4700-1-git-send-email-geert@linux-m68k.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , fs/ubifs/tnc.c: In function ‘search_dh_cookie’: fs/ubifs/tnc.c:1893: warning: ‘err’ is used uninitialized in this function Indeed, err is always used uninitialized. According to an original review comment from Hyunchul, acknowledged by Richard, err should be initialized to -ENOENT to avoid the first call to tnc_next(). But we can achieve the same by reordering the code. Reported-by: Hyunchul Lee Signed-off-by: Geert Uytterhoeven --- Compile-tested only. Still needed in v4.14-rc1, so I'm sending out the patch I wrote in July. This avoids initializing err at the top, so we don't loose the ability to catch future uninitialized use. --- fs/ubifs/tnc.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c index 0a213dcba2a1f0f5..ba3d0e0f86151e53 100644 --- a/fs/ubifs/tnc.c +++ b/fs/ubifs/tnc.c @@ -1890,35 +1890,28 @@ static int search_dh_cookie(struct ubifs_info *c, const union ubifs_key *key, union ubifs_key *dkey; for (;;) { - if (!err) { - err = tnc_next(c, &znode, n); - if (err) - goto out; - } - zbr = &znode->zbranch[*n]; dkey = &zbr->key; if (key_inum(c, dkey) != key_inum(c, key) || key_type(c, dkey) != key_type(c, key)) { - err = -ENOENT; - goto out; + return -ENOENT; } err = tnc_read_hashed_node(c, zbr, dent); if (err) - goto out; + return err; if (key_hash(c, key) == key_hash(c, dkey) && le32_to_cpu(dent->cookie) == cookie) { *zn = znode; - goto out; + return 0; } - } - -out: - return err; + err = tnc_next(c, &znode, n); + if (err) + return err; + } } static int do_lookup_dh(struct ubifs_info *c, const union ubifs_key *key, -- 2.7.4