Patch "dm verity: skip redundant verity_handle_err() on I/O errors" has been added to the 4.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    dm verity: skip redundant verity_handle_err() on I/O errors

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dm-verity-skip-redundant-verity_handle_err-on-i-o-er.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit a1f9c2619550df502a352b6381051bf6d76774b6
Author: Akilesh Kailash <akailash@xxxxxxxxxx>
Date:   Mon Sep 13 09:26:42 2021 +0000

    dm verity: skip redundant verity_handle_err() on I/O errors
    
    [ Upstream commit 2c0468e054c0adb660ac055fc396622ec7235df9 ]
    
    Without FEC, dm-verity won't call verity_handle_err() when I/O fails,
    but with FEC enabled, it currently does even if an I/O error has
    occurred.
    
    If there is an I/O error and FEC correction fails, return the error
    instead of calling verity_handle_err() again.
    
    Suggested-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
    Signed-off-by: Akilesh Kailash <akailash@xxxxxxxxxx>
    Reviewed-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
    Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
    Stable-dep-of: e8c5d45f82ce ("dm verity: fix error handling for check_at_most_once on FEC")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 36945030520a9..08a135f7ef431 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -471,6 +471,7 @@ static int verity_verify_io(struct dm_verity_io *io)
 	struct bvec_iter start;
 	unsigned b;
 	struct crypto_wait wait;
+	struct bio *bio = dm_bio_from_per_bio_data(io, v->ti->per_io_data_size);
 
 	for (b = 0; b < io->n_blocks; b++) {
 		int r;
@@ -525,9 +526,17 @@ static int verity_verify_io(struct dm_verity_io *io)
 		else if (verity_fec_decode(v, io, DM_VERITY_BLOCK_TYPE_DATA,
 					   cur_block, NULL, &start) == 0)
 			continue;
-		else if (verity_handle_err(v, DM_VERITY_BLOCK_TYPE_DATA,
-					   cur_block))
-			return -EIO;
+		else {
+			if (bio->bi_status) {
+				/*
+				 * Error correction failed; Just return error
+				 */
+				return -EIO;
+			}
+			if (verity_handle_err(v, DM_VERITY_BLOCK_TYPE_DATA,
+					      cur_block))
+				return -EIO;
+		}
 	}
 
 	return 0;