[PATCH 5.10 104/105] block: fix memory leak of bvec

[Greg Kroah-Hartman]

From: Ming Lei <ming.lei@xxxxxxxxxx>

commit 8358c28a5d44bf0223a55a2334086c3707bb4185 upstream.

bio_init() clears bio instance, so the bvec index has to be set after
bio_init(), otherwise bio->bi_io_vec may be leaked.

Fixes: 3175199ab0ac ("block: split bio_kmalloc from bio_alloc_bioset")
Cc: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Cc: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
Cc: Damien Le Moal <damien.lemoal@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 block/bio.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/block/bio.c
+++ b/block/bio.c
@@ -491,8 +491,8 @@ struct bio *bio_alloc_bioset(gfp_t gfp_m
 		if (unlikely(!bvl))
 			goto err_free;
 
-		bio->bi_flags |= idx << BVEC_POOL_OFFSET;
 		bio_init(bio, bvl, bvec_nr_vecs(idx));
+		bio->bi_flags |= idx << BVEC_POOL_OFFSET;
 	} else if (nr_iovecs) {
 		bio_init(bio, bio->bi_inline_vecs, BIO_INLINE_VECS);
 	} else {