2018-01-02 12:35:57

by Xiongwei Song

Subject: [PATCH v2] drm/ttm: check the return value of kzalloc

In the function ttm_page_alloc_init, kzalloc call is made for variable
_manager, we need to check its return value, it may return NULL.

Signed-off-by: Xiongwei Song <[email protected]>
---
v1->v2: delete kfree _manager
---
drivers/gpu/drm/ttm/ttm_page_alloc.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
index b5ba6441489f..583d73edb7df 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
@@ -1007,6 +1007,10 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
pr_info("Initializing pool allocator\n");

_manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
+ if (!_manager) {
+ ret = -ENOMEM;
+ goto out;
+ }

ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc", 0);

@@ -1041,6 +1045,8 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
ttm_pool_mm_shrink_init(_manager);

return 0;
+out:
+ return ret;
}

void ttm_page_alloc_fini(void)
--
2.15.1

2018-01-02 12:37:09

by Christian König

Subject: Re: [PATCH v2] drm/ttm: check the return value of kzalloc

Am 02.01.2018 um 13:35 schrieb Xiongwei Song:
> In the function ttm_page_alloc_init, kzalloc call is made for variable
> _manager, we need to check its return value, it may return NULL.
>
> Signed-off-by: Xiongwei Song <[email protected]>
> ---
> v1->v2: delete kfree _manager
> ---
> drivers/gpu/drm/ttm/ttm_page_alloc.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> index b5ba6441489f..583d73edb7df 100644
> --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> @@ -1007,6 +1007,10 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
> pr_info("Initializing pool allocator\n");
>
> _manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
> + if (!_manager) {
> + ret = -ENOMEM;
> + goto out;
> + }

A simpler "return -ENOMEM" should do here as well.

Regards,
Christian.

>
> ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc", 0);
>
> @@ -1041,6 +1045,8 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
> ttm_pool_mm_shrink_init(_manager);
>
> return 0;
> +out:
> + return ret;
> }
>
> void ttm_page_alloc_fini(void)