md: check for failure when adding pages in alloc_behind_master_bio

alloc_behind_master_bio() can possibly add multiple pages to a bio, but it
is not checking for the return value of bio_add_page() if adding really
succeeded.

Check if the page adding succeeded and if not bail out.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/827aa12d44ebf3f50b41b47f5cedc0f80179f2c1.1685532726.git.johannes.thumshirn@wdc.com
[axboe: fold in s/free_page/put_page fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 68a9e2d..9cfb259 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1147,7 +1147,10 @@ static void alloc_behind_master_bio(struct r1bio *r1_bio,
                if (unlikely(!page))
                        goto free_pages;
 
-               bio_add_page(behind_bio, page, len, 0);
+               if (!bio_add_page(behind_bio, page, len, 0)) {
+                       put_page(page);
+                       goto free_pages;
+               }
 
                size -= len;
                i++;