From: Mike Snitzer <snitzer@redhat.com>
Date: Tue, 2 Aug 2011 11:32:00 +0000 (+0100)
Subject: dm mpath: fix potential NULL pointer in feature arg processing
X-Git-Tag: v2.6.33.17~3
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1120616a78cceff1b4a417c61b94da35edf09bdf;p=karo-tx-linux.git

dm mpath: fix potential NULL pointer in feature arg processing

commit 286f367dad40beb3234a18c17391d03ba939a7f3 upstream.

Avoid dereferencing a NULL pointer if the number of feature arguments
supplied is fewer than indicated.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index d43e18611431..a1f088b917fe 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -782,6 +782,11 @@ static int parse_features(struct arg_set *as, struct multipath *m)
 	if (!argc)
 		return 0;
 
+	if (argc > as->argc) {
+		ti->error = "not enough arguments for features";
+		return -EINVAL;
+	}
+
 	do {
 		param_name = shift(as);
 		argc--;