dm flakey: fix logic when corrupting a bio

commit aa56b9b75996ff4c76a0a4181c2fa0206c3d91cc upstream.

If "corrupt_bio_byte" is set to corrupt reads and corrupt_bio_flags is
used, dm-flakey would erroneously return all writes as errors. Likewise,
if "corrupt_bio_byte" is set to corrupt writes, dm-flakey would return
errors for all reads.

Fix the logic so that if fc->corrupt_bio_byte is non-zero, dm-flakey
will not abort reads on writes with an error.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 89fa7a6..220bbf3 100644 (file)
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -361,9 +361,11 @@ static int flakey_map(struct dm_target *ti, struct bio *bio)
                /*
                 * Corrupt matching writes.
                 */
-               if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == WRITE)) {
-                       if (all_corrupt_bio_flags_match(bio, fc))
-                               corrupt_bio_data(bio, fc);
+               if (fc->corrupt_bio_byte) {
+                       if (fc->corrupt_bio_rw == WRITE) {
+                               if (all_corrupt_bio_flags_match(bio, fc))
+                                       corrupt_bio_data(bio, fc);
+                       }
                        goto map_bio;
                }
 
@@ -389,13 +391,14 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio,
                return DM_ENDIO_DONE;
 
        if (!*error && pb->bio_submitted && (bio_data_dir(bio) == READ)) {
-               if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) &&
-                   all_corrupt_bio_flags_match(bio, fc)) {
-                       /*
-                        * Corrupt successful matching READs while in down state.
-                        */
-                       corrupt_bio_data(bio, fc);
-
+               if (fc->corrupt_bio_byte) {
+                       if ((fc->corrupt_bio_rw == READ) &&
+                           all_corrupt_bio_flags_match(bio, fc)) {
+                               /*
+                                * Corrupt successful matching READs while in down state.
+                                */
+                               corrupt_bio_data(bio, fc);
+                       }
                } else if (!test_bit(DROP_WRITES, &fc->flags) &&
                           !test_bit(ERROR_WRITES, &fc->flags)) {
                        /*