[dm-devel] Patch "dm verity: skip redundant verity_handle_err() on I/O errors" has been added to the 5.10-stable tree

[Sasha Levin]

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 5.10-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-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable at vger.kernel.org> know about it.



commit 7635f7aa2fa037de98c77a081dde4219e99edaf7
Author: Akilesh Kailash <akailash at google.com>
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 at google.com>
    Signed-off-by: Akilesh Kailash <akailash at google.com>
    Reviewed-by: Sami Tolvanen <samitolvanen at google.com>
    Signed-off-by: Mike Snitzer <snitzer at redhat.com>
    Stable-dep-of: e8c5d45f82ce ("dm verity: fix error handling for check_at_most_once on FEC")
    Signed-off-by: Sasha Levin <sashal at kernel.org>

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index c801f6b93b7b4..d9c388e6ce76c 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -475,6 +475,7 @@ 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;
@@ -529,9 +530,17 @@ 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;