From: Jan Kara <jack@suse.cz>
Date: Thu, 18 May 2017 23:36:23 +0000 (-0700)
Subject: xfs: Fix off-by-in in loop termination in xfs_find_get_desired_pgoff()
X-Git-Tag: MMI-PSA29.97-13-9~5386^2~4
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d7fd24257aa60316bf81093f7f909dc9475ae974;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git

xfs: Fix off-by-in in loop termination in xfs_find_get_desired_pgoff()

There is an off-by-one error in loop termination conditions in
xfs_find_get_desired_pgoff() since 'end' may index a page beyond end of
desired range if 'endoff' is page aligned. It doesn't have any visible
effects but still it is good to fix it.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f1517e9928c7..dc0e4cb7029b 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1043,7 +1043,7 @@ xfs_find_get_desired_pgoff(
 
 	index = startoff >> PAGE_SHIFT;
 	endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
-	end = endoff >> PAGE_SHIFT;
+	end = (endoff - 1) >> PAGE_SHIFT;
 	do {
 		int		want;
 		unsigned	nr_pages;