block/bio: Do not zero user pages

We don't need to zero fill the bio if not using kernel allocated pages. Fixes: f3587d7 ("block: Clear kernel memory before copying to user") # v4.20-rc2 Reported-by: Todd Aiken <[email protected]> Cc: Laurence Oberman <[email protected]> Cc: [email protected] Cc: Bart Van Assche <[email protected]> Tested-by: Laurence Oberman <[email protected]> Signed-off-by: Keith Busch <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
modi0012 · Dec 10, 2018 · f55adad · f55adad
1 parent 8b878ee
commit f55adad
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/block/bio.c b/block/bio.c
@@ -1261,7 +1261,8 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 		if (ret)
 			goto cleanup;
 	} else {
-		zero_fill_bio(bio);
+		if (bmd->is_our_pages)
+			zero_fill_bio(bio);
 		iov_iter_advance(iter, bio->bi_iter.bi_size);
 	}