[PATCH AUTOSEL 6.6 11/19] ext4: treat end of range as exclusive in ext4_zero_range()

[Sasha Levin <sashal@kernel.org>]

From: Ojaswin Mujoo <ojaswin@linux.ibm.com>

[ Upstream commit 92573369144f40397e8514440afdf59f24905b40 ]

The call to filemap_write_and_wait_range() assumes the range passed to be
inclusive, so fix the call to make sure we follow that.

Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/e503107a7c73a2b68dec645c5ad798c437717c45.1698856309.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/ext4/extents.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 4d8496d1a8ac..4c3e2f38349d 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4522,7 +4522,8 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 	 * Round up offset. This is not fallocate, we need to zero out
 	 * blocks, so convert interior block aligned part of the range to
 	 * unwritten and possibly manually zero out unaligned parts of the
-	 * range.
+	 * range. Here, start and partial_begin are inclusive, end and
+	 * partial_end are exclusive.
 	 */
 	start = round_up(offset, 1 << blkbits);
 	end = round_down((offset + len), 1 << blkbits);
@@ -4608,7 +4609,8 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 		 * disk in case of crash before zeroing trans is committed.
 		 */
 		if (ext4_should_journal_data(inode)) {
-			ret = filemap_write_and_wait_range(mapping, start, end);
+			ret = filemap_write_and_wait_range(mapping, start,
+							   end - 1);
 			if (ret) {
 				filemap_invalidate_unlock(mapping);
 				goto out_mutex;
-- 
2.43.0