2022-02-25 11:25:37

by Jia-Ju Bai

Subject: [PATCH] md: bcache: check the return value of mempool_alloc() in bch_btree_node_read_done()

The function mempool_alloc() in bch_btree_node_read_done() can fail, so
its return value should be checked.

Fixes: d19936a26658 ("bcache: convert to bioset_init()/mempool_init()")
Reported-by: TOTE Robot <[email protected]>
Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/md/bcache/btree.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 88c573eeb598..fb8b7dd6bcc2 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -157,6 +157,8 @@ void bch_btree_node_read_done(struct btree *b)
* See the comment arount cache_set->fill_iter.
*/
iter = mempool_alloc(&b->c->fill_iter, GFP_NOIO);
+ if (!iter)
+ return;
iter->size = b->c->cache->sb.bucket_size / b->c->cache->sb.block_size;
iter->used = 0;

--
2.17.1

2022-03-02 23:45:05

by Coly Li

Subject: Re: [PATCH] md: bcache: check the return value of mempool_alloc() in bch_btree_node_read_done()

On 2/25/22 4:28 PM, Jia-Ju Bai wrote:
> The function mempool_alloc() in bch_btree_node_read_done() can fail, so
> its return value should be checked.
>
> Fixes: d19936a26658 ("bcache: convert to bioset_init()/mempool_init()")
> Reported-by: TOTE Robot <[email protected]>
> Signed-off-by: Jia-Ju Bai <[email protected]>
> ---
> drivers/md/bcache/btree.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
> index 88c573eeb598..fb8b7dd6bcc2 100644
> --- a/drivers/md/bcache/btree.c
> +++ b/drivers/md/bcache/btree.c
> @@ -157,6 +157,8 @@ void bch_btree_node_read_done(struct btree *b)
> * See the comment arount cache_set->fill_iter.
> */
> iter = mempool_alloc(&b->c->fill_iter, GFP_NOIO);
> + if (!iter)
> + return;


This is unnecessary, mempool_alloc() doesn't return NULL in this condition.


Coly Li



> iter->size = b->c->cache->sb.bucket_size / b->c->cache->sb.block_size;
> iter->used = 0;
>