@@ -900,7 +900,6 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input)
struct uvc_fh *handle = fh;
struct uvc_video_chain *chain = handle->chain;
int ret;
- u8 i;
if (chain->selector == NULL ||
(chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
@@ -910,11 +909,11 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input)
ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, chain->selector->id,
chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL,
- &i, 1);
+ &chain->input, 1);
if (ret < 0)
return ret;
- *input = i - 1;
+ *input = chain->input - 1;
return 0;
}
@@ -923,7 +922,6 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input)
struct uvc_fh *handle = fh;
struct uvc_video_chain *chain = handle->chain;
int ret;
- u32 i;
ret = uvc_acquire_privileges(handle);
if (ret < 0)
@@ -939,10 +937,10 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input)
if (input >= chain->selector->bNrInPins)
return -EINVAL;
- i = input + 1;
+ chain->input = input + 1;
return uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id,
chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL,
- &i, 1);
+ &chain->input, 1);
}
static int uvc_ioctl_queryctrl(struct file *file, void *fh,
@@ -475,6 +475,9 @@ struct uvc_video_chain {
struct mutex ctrl_mutex; /* Protects ctrl.info */
struct v4l2_prio_state prio; /* V4L2 priority state */
+
+ u8 input; /* buffer for set/get input */
+
u32 caps; /* V4L2 chain-wide caps */
};
As warned by smatch: drivers/media/usb/uvc/uvc_v4l2.c:911 uvc_ioctl_g_input() error: doing dma on the stack (&i) drivers/media/usb/uvc/uvc_v4l2.c:943 uvc_ioctl_s_input() error: doing dma on the stack (&i) those two functions call uvc_query_ctrl passing a pointer to a data at the DMA stack. those are used to send URBs via usb_control_msg(). Using DMA stack is not supported and should not work anymore on modern Linux versions. So, use a temporary buffer, allocated together with struct uvc_video_chain. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> --- drivers/media/usb/uvc/uvc_v4l2.c | 10 ++++------ drivers/media/usb/uvc/uvcvideo.h | 3 +++ 2 files changed, 7 insertions(+), 6 deletions(-)