4.7-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sami Tolvanen <[email protected]> commit 602d1657c603eedd7379a8bcde1ad3a2972ecc5f upstream. do_div was replaced with div64_u64 at some point, causing a bug with block calculation due to incompatible semantics of the two functions. Signed-off-by: Sami Tolvanen <[email protected]> Fixes: a739ff3f543a ("dm verity: add support for forward error correction") Signed-off-by: Mike Snitzer <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/md/dm-verity-fec.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/md/dm-verity-fec.c +++ b/drivers/md/dm-verity-fec.c @@ -453,9 +453,7 @@ int verity_fec_decode(struct dm_verity * */ offset = block << v->data_dev_block_bits; - - res = offset; - div64_u64(res, v->fec->rounds << v->data_dev_block_bits); + res = div64_u64(offset, v->fec->rounds << v->data_dev_block_bits); /* * The base RS block we can feed to the interleaver to find out all
