The 'lend' parameter of truncate_inode_pages_range is required to be
inclusive, so follow the rule.

This patch fixes one memory corruption triggered by discard.

Cc: <redacted>
Cc: Dmitry Monakhov <redacted>
Fixes: 351499a172c0 ("block: Invalidate cache on discard v2")
Signed-off-by: Ming Lei <redacted>
---
V2:
        - Cc stable list and Dmitry as suggested by Bart

 block/ioctl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/ioctl.c b/block/ioctl.c
index 1668506d8ed8..3884d810efd2 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c

@@ -225,7 +225,7 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,

        if (start + len > i_size_read(bdev->bd_inode))
                return -EINVAL;
-       truncate_inode_pages_range(mapping, start, start + len);
+       truncate_inode_pages_range(mapping, start, start + len - 1);
        return blkdev_issue_discard(bdev, start >> 9, len >> 9,
                                    GFP_KERNEL, flags);
 }
--

2.9.5