From: Geyslan G. Bem <geyslan@gmail.com>
Date: Wed, 30 Oct 2013 21:01:00 +0000 (-0500)
Subject: xfs: fix possible NULL dereference in xlog_verify_iclog
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=643f7c4e5656bd18c769211f933190f7bb738245;p=deliverable%2Flinux.git

xfs: fix possible NULL dereference in xlog_verify_iclog

In xlog_verify_iclog a debug check of the incore log buffers prints an
error if icptr is null and then goes on to dereference the pointer
regardless.  Convert this to an assert so that the intention is clear.
This was reported by Coverty.

Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
---

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index e523396753c5..49dd41e6a2dc 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -3710,11 +3710,9 @@ xlog_verify_iclog(
 	/* check validity of iclog pointers */
 	spin_lock(&log->l_icloglock);
 	icptr = log->l_iclog;
-	for (i=0; i < log->l_iclog_bufs; i++) {
-		if (icptr == NULL)
-			xfs_emerg(log->l_mp, "%s: invalid ptr", __func__);
-		icptr = icptr->ic_next;
-	}
+	for (i = 0; i < log->l_iclog_bufs; i++, icptr = icptr->ic_next)
+		ASSERT(icptr);
+
 	if (icptr != log->l_iclog)
 		xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__);
 	spin_unlock(&log->l_icloglock);