From: Sunwook Eom speed.eom@samsung.com
commit ad4e80a639fc61d5ecebb03caa5cdbfb91fcebfc upstream.
The error correction data is computed as if data and hash blocks were concatenated. But hash block number starts from v->hash_start. So, we have to calculate hash block number based on that.
Fixes: a739ff3f543af ("dm verity: add support for forward error correction") Cc: stable@vger.kernel.org Signed-off-by: Sunwook Eom speed.eom@samsung.com Reviewed-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/md/dm-verity-fec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/dm-verity-fec.c +++ b/drivers/md/dm-verity-fec.c @@ -435,7 +435,7 @@ int verity_fec_decode(struct dm_verity * fio->level++;
if (type == DM_VERITY_BLOCK_TYPE_METADATA) - block += v->data_blocks; + block = block - v->hash_start + v->data_blocks;
/* * For RS(M, N), the continuous FEC data is divided into blocks of N