dm cache metadata: verify cache has blocks in blocks_are_clean_separate_dirty()

Otherwise dm_bitset_cursor_begin() return -ENODATA.  Other calls to
dm_bitset_cursor_begin() have similar negative checks.

Fixes inability to create a cache in passthrough mode (even though doing
so makes no sense).

Fixes: 0d963b6e65 ("dm cache metadata: fix metadata2 format's blocks_are_clean_separate_dirty")
Cc: stable@vger.kernel.org
Reported-by: David Teigland <teigland@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Mike Snitzer 2018-11-09 11:56:03 -05:00
parent 2595646791
commit 687cf4412a

View File

@ -930,6 +930,10 @@ static int blocks_are_clean_separate_dirty(struct dm_cache_metadata *cmd,
bool dirty_flag;
*result = true;
if (from_cblock(cmd->cache_blocks) == 0)
/* Nothing to do */
return 0;
r = dm_bitset_cursor_begin(&cmd->dirty_info, cmd->dirty_root,
from_cblock(cmd->cache_blocks), &cmd->dirty_cursor);
if (r) {