[PATCH] ext3 balloc: fix _with_rsv freeze

Port fix to the off-by-one in find_next_usable_block's memscan from ext2 to
ext3; but it didn't cause a serious problem for ext3 because the additional
ext3_test_allocatable check rescued it from the error.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index 5a2c198762f0..22161740ba29 100644
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -730,7 +730,7 @@ find_next_usable_block(ext3_grpblk_t start, struct buffer_head *bh,
                 here = 0;
 
         p = ((char *)bh->b_data) + (here >> 3);
-        r = memscan(p, 0, (maxblocks - here + 7) >> 3);
+        r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3));
         next = (r - ((char *)bh->b_data)) << 3;
 
         if (next < maxblocks && next >= start && ext3_test_allocatable(next, bh))