From: Yan, Zheng <zheng.z.yan@linux.intel.com>
Date: Mon, 6 Dec 2010 07:02:36 +0000 (+0000)
Subject: Btrfs: Fix page leak in compressed writeback path
X-Git-Tag: upstream/snapshot3+hdmi~11282^2~67
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=24ae63656a165c870c0d69fcc8aac1dc35e25e34;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

Btrfs: Fix page leak in compressed writeback path

"start + num_bytes >= actual_end" can happen when compressed page writeback races
with file truncation. In that case we need unlock and release pages past the end
of file.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ae6c0d1..4875d69 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -495,7 +495,7 @@ again:
 		add_async_extent(async_cow, start, num_bytes,
 				 total_compressed, pages, nr_pages_ret);
 
-		if (start + num_bytes < end && start + num_bytes < actual_end) {
+		if (start + num_bytes < end) {
 			start += num_bytes;
 			pages = NULL;
 			cond_resched();