Only call truncate_bdev_range() if the fallocate mode is supported. This
fixes a bug where data in the pagecache could be invalidated if the
fallocate() was called on the block device with an invalid mode.
Fixes: 25f4c41415e5 ("block: implement (some of) fallocate for block devices")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Signed-off-by: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231011201230.750105-1-sarthakkukreti@xxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
(cherry picked from commit 1364a3c391aedfeb32aa025303ead3d7c91cdf9d)
Signed-off-by: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxxxx>
---
fs/block_dev.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index fa329c7eddf0..e528ad860143 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -2114,21 +2114,26 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start,
if ((start | len) & (bdev_logical_block_size(bdev) - 1))
return -EINVAL;
- /* Invalidate the page cache, including dirty pages. */
+ /*
+ * Invalidate the page cache, including dirty pages, for valid
+ * de-allocate mode calls to fallocate().
+ */
mapping = bdev->bd_inode->i_mapping;
- truncate_inode_pages_range(mapping, start, end);
switch (mode) {
case FALLOC_FL_ZERO_RANGE:
case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE:
+ truncate_inode_pages_range(mapping, start, end);
error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
break;
case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE:
+ truncate_inode_pages_range(mapping, start, end);
error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK);
break;
case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE:
+ truncate_inode_pages_range(mapping, start, end);
error = blkdev_issue_discard(bdev, start >> 9, len >> 9,
GFP_KERNEL, 0);
break;
--
2.43.0.472.g3155946c3a-goog
