allegro_open() misses checks for v4l2_m2m_ctx_init() and results of
v4l2_ctrl_new* calls.
Add checks and error handlers to fix the problems.
Signed-off-by: Chuhong Yuan <[email protected]>
---
Changes in v3:
- Make code cleaner.
- Add a check for handler->error.
.../staging/media/allegro-dvt/allegro-core.c | 24 +++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
index 6f0cd0784786..e86001e42963 100644
--- a/drivers/staging/media/allegro-dvt/allegro-core.c
+++ b/drivers/staging/media/allegro-dvt/allegro-core.c
@@ -2270,15 +2270,12 @@ 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)
return -ENOMEM;
- v4l2_fh_init(&channel->fh, vdev);
- file->private_data = &channel->fh;
- v4l2_fh_add(&channel->fh);
-
init_completion(&channel->completion);
channel->dev = dev;
@@ -2328,6 +2325,11 @@ static int allegro_open(struct file *file)
V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,
1, 32,
1, 1);
+ if (handler->error != 0) {
+ ret = handler->error;
+ goto error;
+ }
+
channel->fh.ctrl_handler = handler;
channel->mcu_channel_id = -1;
@@ -2341,7 +2343,21 @@ 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);
+ goto error;
+ }
+
+ v4l2_fh_init(&channel->fh, vdev);
+ file->private_data = &channel->fh;
+ v4l2_fh_add(&channel->fh);
+
return 0;
+
+error:
+ v4l2_ctrl_handler_free(handler);
+ kfree(channel);
+ return ret;
}
static int allegro_release(struct file *file)
--
2.24.1
On Mon, 13 Jan 2020 13:59:51 +0800, Chuhong Yuan wrote:
> allegro_open() misses checks for v4l2_m2m_ctx_init() and results of
> v4l2_ctrl_new* calls.
> Add checks and error handlers to fix the problems.
>
> Signed-off-by: Chuhong Yuan <[email protected]>
> ---
> Changes in v3:
> - Make code cleaner.
> - Add a check for handler->error.
>
> .../staging/media/allegro-dvt/allegro-core.c | 24 +++++++++++++++----
> 1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
> index 6f0cd0784786..e86001e42963 100644
> --- a/drivers/staging/media/allegro-dvt/allegro-core.c
> +++ b/drivers/staging/media/allegro-dvt/allegro-core.c
> @@ -2270,15 +2270,12 @@ 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)
> return -ENOMEM;
>
> - v4l2_fh_init(&channel->fh, vdev);
> - file->private_data = &channel->fh;
> - v4l2_fh_add(&channel->fh);
> -
> init_completion(&channel->completion);
>
> channel->dev = dev;
> @@ -2328,6 +2325,11 @@ static int allegro_open(struct file *file)
> V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,
> 1, 32,
> 1, 1);
> + if (handler->error != 0) {
> + ret = handler->error;
> + goto error;
> + }
> +
> channel->fh.ctrl_handler = handler;
>
> channel->mcu_channel_id = -1;
> @@ -2341,7 +2343,21 @@ 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);
> + goto error;
> + }
> +
> + v4l2_fh_init(&channel->fh, vdev);
This call sets channel->fh.ctrl_handler to vdev->ctrl_handler, which
has previously been overriden by the driver to handler. Therefore, this
patch breaks all controls. I think we should initialize channel->fh
before setting any fields of this struct.
Michael
> + file->private_data = &channel->fh;
> + v4l2_fh_add(&channel->fh);
> +
> return 0;
> +
> +error:
> + v4l2_ctrl_handler_free(handler);
> + kfree(channel);
> + return ret;
> }
>
> static int allegro_release(struct file *file)
On Tue, Jan 21, 2020 at 4:23 PM Michael Tretter
<[email protected]> wrote:
>
> On Mon, 13 Jan 2020 13:59:51 +0800, Chuhong Yuan wrote:
> > allegro_open() misses checks for v4l2_m2m_ctx_init() and results of
> > v4l2_ctrl_new* calls.
> > Add checks and error handlers to fix the problems.
> >
> > Signed-off-by: Chuhong Yuan <[email protected]>
> > ---
> > Changes in v3:
> > - Make code cleaner.
> > - Add a check for handler->error.
> >
> > .../staging/media/allegro-dvt/allegro-core.c | 24 +++++++++++++++----
> > 1 file changed, 20 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
> > index 6f0cd0784786..e86001e42963 100644
> > --- a/drivers/staging/media/allegro-dvt/allegro-core.c
> > +++ b/drivers/staging/media/allegro-dvt/allegro-core.c
> > @@ -2270,15 +2270,12 @@ 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)
> > return -ENOMEM;
> >
> > - v4l2_fh_init(&channel->fh, vdev);
> > - file->private_data = &channel->fh;
> > - v4l2_fh_add(&channel->fh);
> > -
> > init_completion(&channel->completion);
> >
> > channel->dev = dev;
> > @@ -2328,6 +2325,11 @@ static int allegro_open(struct file *file)
> > V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,
> > 1, 32,
> > 1, 1);
> > + if (handler->error != 0) {
> > + ret = handler->error;
> > + goto error;
> > + }
> > +
> > channel->fh.ctrl_handler = handler;
> >
> > channel->mcu_channel_id = -1;
> > @@ -2341,7 +2343,21 @@ 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);
> > + goto error;
> > + }
> > +
> > + v4l2_fh_init(&channel->fh, vdev);
>
> This call sets channel->fh.ctrl_handler to vdev->ctrl_handler, which
> has previously been overriden by the driver to handler. Therefore, this
> patch breaks all controls. I think we should initialize channel->fh
> before setting any fields of this struct.
>
I'm not very clear about this issue.
In my second version, Hans replied that init could be moved before return 0.
I have sent this mail to him.
> Michael
>
> > + file->private_data = &channel->fh;
> > + v4l2_fh_add(&channel->fh);
> > +
> > return 0;
> > +
> > +error:
> > + v4l2_ctrl_handler_free(handler);
> > + kfree(channel);
> > + return ret;
> > }
> >
> > static int allegro_release(struct file *file)
On Tue, 21 Jan 2020 19:59:46 +0800, Chuhong Yuan wrote:
> On Tue, Jan 21, 2020 at 4:23 PM Michael Tretter
> <[email protected]> wrote:
> >
> > On Mon, 13 Jan 2020 13:59:51 +0800, Chuhong Yuan wrote:
> > > allegro_open() misses checks for v4l2_m2m_ctx_init() and results of
> > > v4l2_ctrl_new* calls.
> > > Add checks and error handlers to fix the problems.
> > >
> > > Signed-off-by: Chuhong Yuan <[email protected]>
> > > ---
> > > Changes in v3:
> > > - Make code cleaner.
> > > - Add a check for handler->error.
> > >
> > > .../staging/media/allegro-dvt/allegro-core.c | 24 +++++++++++++++----
> > > 1 file changed, 20 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
> > > index 6f0cd0784786..e86001e42963 100644
> > > --- a/drivers/staging/media/allegro-dvt/allegro-core.c
> > > +++ b/drivers/staging/media/allegro-dvt/allegro-core.c
> > > @@ -2270,15 +2270,12 @@ 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)
> > > return -ENOMEM;
> > >
> > > - v4l2_fh_init(&channel->fh, vdev);
> > > - file->private_data = &channel->fh;
> > > - v4l2_fh_add(&channel->fh);
> > > -
> > > init_completion(&channel->completion);
> > >
> > > channel->dev = dev;
> > > @@ -2328,6 +2325,11 @@ static int allegro_open(struct file *file)
> > > V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,
> > > 1, 32,
> > > 1, 1);
> > > + if (handler->error != 0) {
> > > + ret = handler->error;
> > > + goto error;
> > > + }
> > > +
> > > channel->fh.ctrl_handler = handler;
> > >
> > > channel->mcu_channel_id = -1;
> > > @@ -2341,7 +2343,21 @@ 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);
> > > + goto error;
> > > + }
> > > +
> > > + v4l2_fh_init(&channel->fh, vdev);
> >
> > This call sets channel->fh.ctrl_handler to vdev->ctrl_handler, which
> > has previously been overriden by the driver to handler. Therefore, this
> > patch breaks all controls. I think we should initialize channel->fh
> > before setting any fields of this struct.
> >
>
> I'm not very clear about this issue.
> In my second version, Hans replied that init could be moved before return 0.
> I have sent this mail to him.
This driver uses its own v4l2_ctrl_handler, which is initialized in this
function (see the "handler" variable). After the initialization, the
handler is added to the fh as
channel->fh.ctrl_handler = handler;
to override the ctrl_handler of the fh.
However, the v4l2_fh_init() function re-initializes the ctrl_handler of
the fh
/* Inherit from video_device. May be overridden by the driver. */
fh->ctrl_handler = vdev->ctrl_handler;
which reverts the ctrl_handler override by the driver.
Therefore, the ctrl_handler must be overridden after the call to
v4l2_fh_init().
Michael
>
> > Michael
> >
> > > + file->private_data = &channel->fh;
> > > + v4l2_fh_add(&channel->fh);
> > > +
> > > return 0;
> > > +
> > > +error:
> > > + v4l2_ctrl_handler_free(handler);
> > > + kfree(channel);
> > > + return ret;
> > > }
> > >
> > > static int allegro_release(struct file *file)
>