Hi Dan,
Thank you for the patch.
On Tue, Jul 19, 2022 at 04:45:29PM +0300, Dan Carpenter wrote:
> There is a path where "mapping" is NULL when we try to process the
> common mappings so it will crash.
>
> Fixes: 86f7ef773156 ("media: uvcvideo: Add support for per-device control mapping overrides")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
I've submitted [1] to fix this issue, and [2] to replace all the
error-prone loops in this function.
[1] https://lore.kernel.org/linux-media/20220718121219.16079-1-laurent.pinchart@xxxxxxxxxxxxxxxx/
[2] https://lore.kernel.org/linux-media/20220718222757.8203-1-laurent.pinchart@xxxxxxxxxxxxxxxx/T/#u
> ---
> This bug was previously reported by the kbuild bot and fixed in later
> versions of the patchset. The git log doesn't have a link to
> lore.kernel.org but I suspect an earlier version got merged?
>
> drivers/media/usb/uvc/uvc_ctrl.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index e4826a846861..00ea894e79fd 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -2413,9 +2413,9 @@ static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
> {
> const struct uvc_control_info *info = uvc_ctrls;
> const struct uvc_control_info *iend = info + ARRAY_SIZE(uvc_ctrls);
> - const struct uvc_control_mapping *mapping = uvc_ctrl_mappings;
> - const struct uvc_control_mapping *mend =
> - mapping + ARRAY_SIZE(uvc_ctrl_mappings);
> + const struct uvc_control_mapping *mapping;
> + const struct uvc_control_mapping *mend;
> + unsigned int i;
>
> /*
> * XU controls initialization requires querying the device for control
> @@ -2453,7 +2453,6 @@ static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
> */
> if (chain->dev->info->mappings) {
> bool custom = false;
> - unsigned int i;
>
> for (i = 0; (mapping = chain->dev->info->mappings[i]); ++i) {
> if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
> @@ -2468,7 +2467,8 @@ static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
> }
>
> /* Process common mappings next. */
> - for (; mapping < mend; ++mapping) {
> + for (i = 0; i < ARRAY_SIZE(uvc_ctrl_mappings); i++) {
> + mapping = &uvc_ctrl_mappings[i];
> if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
> ctrl->info.selector == mapping->selector)
> __uvc_ctrl_add_mapping(chain, ctrl, mapping);
> --
> 2.35.1
>
--
Regards,
Laurent Pinchart
