[PATCH] block: Clear kernel memory before copying to user

[Keith Busch <keith.busch@xxxxxxxxx>]

If the kernel allocates a bounce buffer for user read data, this memory
needs to be cleared before copying it to the user, otherwise it may leak
kernel memory to user space.

Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
---
 block/bio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/block/bio.c b/block/bio.c
index d5368a445561..a50d59236b19 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1260,6 +1260,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 		if (ret)
 			goto cleanup;
 	} else {
+		zero_fill_bio(bio);
 		iov_iter_advance(iter, bio->bi_iter.bi_size);
 	}
 
-- 
2.14.4