From: Sunwook Eom Date: Fri, 10 Apr 2020 03:54:19 +0000 (+0900) Subject: dm verity fec: fix hash block number in verity_fec_decode X-Git-Tag: v4.14.179~12 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=74381a0cf22edda38dbb8cb492ce4d097868b195;p=thirdparty%2Fkernel%2Fstable.git dm verity fec: fix hash block number in verity_fec_decode 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 Reviewed-by: Sami Tolvanen Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c index 285148100cdec..0fe6cc3007f58 100644 --- a/drivers/md/dm-verity-fec.c +++ b/drivers/md/dm-verity-fec.c @@ -436,7 +436,7 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io, 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