2020-06-20 04:57:01

by Gustavo A. R. Silva

Subject: [PATCH][next] blk-iocost: Use struct_size() in kzalloc_node()

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Addresses-KSPP-ID: https://github.com/KSPP/linux/issues/83
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
block/blk-iocost.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 8ac4aad66ebc..cea5ee9be639 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -2045,8 +2045,7 @@ static struct blkg_policy_data *ioc_pd_alloc(gfp_t gfp, struct request_queue *q,
int levels = blkcg->css.cgroup->level + 1;
struct ioc_gq *iocg;

- iocg = kzalloc_node(sizeof(*iocg) + levels * sizeof(iocg->ancestors[0]),
- gfp, q->node);
+ iocg = kzalloc_node(struct_size(iocg, ancestors, levels), gfp, q->node);
if (!iocg)
return NULL;

--
2.27.0

2020-06-20 21:30:20

by Jens Axboe

Subject: Re: [PATCH][next] blk-iocost: Use struct_size() in kzalloc_node()

On 6/19/20 5:08 PM, Gustavo A. R. Silva wrote:
> Make use of the struct_size() helper instead of an open-coded version
> in order to avoid any potential type mistakes.
>
> This code was detected with the help of Coccinelle and, audited and
> fixed manually.

Applied, thanks.

--
Jens Axboe