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") Signed-off-by: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxxxx> --- block/fops.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/block/fops.c b/block/fops.c index d2e6be4e3d1c..d359254c645d 100644 --- a/block/fops.c +++ b/block/fops.c @@ -648,26 +648,37 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, filemap_invalidate_lock(inode->i_mapping); - /* Invalidate the page cache, including dirty pages. */ - error = truncate_bdev_range(bdev, file->f_mode, start, end); - if (error) - goto fail; - + /* + * Invalidate the page cache, including dirty pages, for valid + * de-allocate mode calls to fallocate(). + */ switch (mode) { case FALLOC_FL_ZERO_RANGE: case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> SECTOR_SHIFT, - len >> SECTOR_SHIFT, GFP_KERNEL, - BLKDEV_ZERO_NOUNMAP); + error = truncate_bdev_range(bdev, file->f_mode, start, end); + if (!error) + error = blkdev_issue_zeroout(bdev, + start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, + GFP_KERNEL, + BLKDEV_ZERO_NOUNMAP); break; case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: - error = blkdev_issue_zeroout(bdev, start >> SECTOR_SHIFT, - len >> SECTOR_SHIFT, GFP_KERNEL, - BLKDEV_ZERO_NOFALLBACK); + error = truncate_bdev_range(bdev, file->f_mode, start, end); + if (!error) + error = blkdev_issue_zeroout(bdev, + start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, + GFP_KERNEL, + BLKDEV_ZERO_NOFALLBACK); break; case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE: - error = blkdev_issue_discard(bdev, start >> SECTOR_SHIFT, - len >> SECTOR_SHIFT, GFP_KERNEL); + error = truncate_bdev_range(bdev, file->f_mode, start, end); + if (!error) + error = blkdev_issue_discard(bdev, + start >> SECTOR_SHIFT, + len >> SECTOR_SHIFT, + GFP_KERNEL); break; default: error = -EOPNOTSUPP; -- 2.40.0.634.g4ca3ef3211-goog -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel