[v2] media: allegro: add the missed check for v4l2_m2m_ctx_init
Commit Message
allegro_open() misses a check for v4l2_m2m_ctx_init().
Add a check and error handling code to fix it.
Fixes: f20387dfd065 ("media: allegro: add Allegro DVT video IP core driver")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
---
Changes in v2:
- Fix the use-after-free in v1.
drivers/staging/media/allegro-dvt/allegro-core.c | 9 +++++++++
1 file changed, 9 insertions(+)
Comments
On 12/10/19 4:15 AM, Chuhong Yuan wrote:
> allegro_open() misses a check for v4l2_m2m_ctx_init().
> Add a check and error handling code to fix it.
>
> Fixes: f20387dfd065 ("media: allegro: add Allegro DVT video IP core driver")
> Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
> ---
> Changes in v2:
> - Fix the use-after-free in v1.
>
> drivers/staging/media/allegro-dvt/allegro-core.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
> index 6f0cd0784786..66736beb67af 100644
> --- a/drivers/staging/media/allegro-dvt/allegro-core.c
> +++ b/drivers/staging/media/allegro-dvt/allegro-core.c
> @@ -2270,6 +2270,7 @@ static int allegro_open(struct file *file)
> struct allegro_channel *channel = NULL;
> struct v4l2_ctrl_handler *handler;
> u64 mask;
> + int ret;
>
> channel = kzalloc(sizeof(*channel), GFP_KERNEL);
> if (!channel)
> @@ -2341,6 +2342,14 @@ static int allegro_open(struct file *file)
> channel->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, channel,
> allegro_queue_init);
>
> + if (IS_ERR(channel->fh.m2m_ctx)) {
> + ret = PTR_ERR(channel->fh.m2m_ctx);
> + v4l2_fh_del(&channel->fh);
> + v4l2_fh_exit(&channel->fh);
Just move the v4l2_fh_init/add calls to just before the return 0, i.e. when everything
is right. Then you don't need to call del/exit on error.
Also, I see that the result of all the v4l2_ctrl_new* calls isn't checked.
Just after the last v4l2_ctrl_new_std() call you need to check handler->error:
if not 0, then there was an error and you need to call v4l2_ctrl_handler_free
to clean it up.
Regards,
Hans
> + kfree(channel);
> + return ret;
> + }
> +
> return 0;
> }
>
>
@@ -2270,6 +2270,7 @@ static int allegro_open(struct file *file)
struct allegro_channel *channel = NULL;
struct v4l2_ctrl_handler *handler;
u64 mask;
+ int ret;
channel = kzalloc(sizeof(*channel), GFP_KERNEL);
if (!channel)
@@ -2341,6 +2342,14 @@ static int allegro_open(struct file *file)
channel->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, channel,
allegro_queue_init);
+ if (IS_ERR(channel->fh.m2m_ctx)) {
+ ret = PTR_ERR(channel->fh.m2m_ctx);
+ v4l2_fh_del(&channel->fh);
+ v4l2_fh_exit(&channel->fh);
+ kfree(channel);
+ return ret;
+ }
+
return 0;
}