Commit 0d1e0bea authored Jul 11, 2017 by Liu Bo Committed by David Sterba Aug 16, 2017

Btrfs: report errors when checksum is not found



When btrfs fails the checksum check, it'll fill the whole page with
"1".

However, if %csum_expected is 0 (which means there is no checksum), then
for some unknown reason, we just pretend that the read is correct, so
userspace would be confused about the dilemma that read is successful but
getting a page with all content being "1".

This can happen due to a bug in btrfs-convert.

This fixes it by always returning errors if checksum doesn't match.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

parent 69f03f13

fs/btrfs/inode.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -3159,8 +3159,6 @@ zeroit:
		memset(kaddr + pgoff, 1, len);
		flush_dcache_page(page);
		kunmap_atomic(kaddr);
		if (csum_expected == 0)
		return 0;
		return -EIO;
		}

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