On 04/12, Jaegeuk Kim wrote:

From: Jaegeuk Kim jaegeuk@google.com

commit df7b59ba9245 ("dm verity: fix FEC for RS roots unaligned to block size") made dm_bufio->block_size 1024, if f->roots is 2. But, that gives the below EIO if the logical block size of the device is 4096, given v->data_dev_block_bits=12.

E sd 0 : 0:0:0: [sda] tag#30 request not aligned to the logical block size E blk_update_request: I/O error, dev sda, sector 10368424 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0 E device-mapper: verity-fec: 254:8: FEC 9244672: parity read failed (block 18056): -5

Let's use f->roots for dm_bufio iff it's aligned to v->data_dev_block_bits.

Fixes: df7b59ba9245 ("dm verity: fix FEC for RS roots unaligned to block size") Cc: stable@vger.kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@google.com

---

drivers/md/dm-verity-fec.c | 11 ++++++++--- drivers/md/dm-verity-fec.h | 1 + 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c index 66f4c6398f67..cea2b3789736 100644 --- a/drivers/md/dm-verity-fec.c +++ b/drivers/md/dm-verity-fec.c @@ -65,7 +65,7 @@ static u8 *fec_read_parity(struct dm_verity *v, u64 rsb, int index, u8 *res; position = (index + rsb) * v->fec->roots;

• block = div64_u64_rem(position, v->fec->roots << SECTOR_SHIFT, &rem);

• block = div64_u64_rem(position, v->fec->io_size, &rem); *offset = (unsigned)rem;

res = dm_bufio_read(v->fec->bufio, block, buf); @@ -154,7 +154,7 @@ static int fec_decode_bufs(struct dm_verity *v, struct dm_verity_fec_io *fio, /* read the next block when we run out of parity bytes */ offset += v->fec->roots;

• if (offset >= v->fec->roots << SECTOR_SHIFT) {
  

• if (offset >= v->fec->io_size) {
  dm_bufio_release(buf);
  

par = fec_read_parity(v, rsb, block_offset, &offset, &buf); @@ -742,8 +742,13 @@ int verity_fec_ctr(struct dm_verity *v) return -E2BIG; }

• if ((f->roots << SECTOR_SHIFT) & ((1 << v->data_dev_block_bits) - 1))

• f->io_size = 1 << v->data_dev_block_bits;
  

• else

• f->io_size = v->fec->roots << SECTOR_SHIFT;
  

• f->bufio = dm_bufio_client_create(f->dev->bdev,

• 			  f->roots << SECTOR_SHIFT,
  

• 			  f->io_size,
  		  1, 0, NULL, NULL);
  

  if (IS_ERR(f->bufio)) { ti->error = "Cannot initialize FEC bufio client";

diff --git a/drivers/md/dm-verity-fec.h b/drivers/md/dm-verity-fec.h index 42fbd3a7fc9f..3c46c8d61883 100644 --- a/drivers/md/dm-verity-fec.h +++ b/drivers/md/dm-verity-fec.h @@ -36,6 +36,7 @@ struct dm_verity_fec { struct dm_dev *dev; /* parity data device */ struct dm_bufio_client *data_bufio; /* for data dev access */ struct dm_bufio_client *bufio; /* for parity data access */

• size_t io_size; /* IO size for roots */ sector_t start; /* parity data start in blocks */ sector_t blocks; /* number of blocks covered */ sector_t rounds; /* number of interleaving rounds */

-- 2.31.1.295.g9ea45b61b8-goog