From c5833ac1da1d7b8a3b7fb56b51b72293efda072e Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 14 Feb 2018 13:03:18 +0100 Subject: [PATCH] media: v4l2-compat-ioctl32.c: fix ctrl_is_pointer commit b8c601e8af2d08f733d74defa8465303391bb930 upstream. ctrl_is_pointer just hardcoded two known string controls, but that caused problems when using e.g. custom controls that use a pointer for the payload. Reimplement this function: it now finds the v4l2_ctrl (if the driver uses the control framework) or it calls vidioc_query_ext_ctrl (if the driver implements that directly). In both cases it can now check if the control is a pointer control or not. Signed-off-by: Hans Verkuil Acked-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab [bwh: Rebased on top of some earlier fixes] Signed-off-by: Ben Hutchings --- drivers/media/video/v4l2-compat-ioctl32.c | 51 ++++++++++++++--------- 1 file changed, 32 insertions(+), 19 deletions(-) diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c index 1cde4c588d2b..714dfdc6302d 100644 --- a/drivers/media/video/v4l2-compat-ioctl32.c +++ b/drivers/media/video/v4l2-compat-ioctl32.c @@ -17,6 +17,9 @@ #include #include #include +#include +#include +#include #ifdef CONFIG_COMPAT @@ -572,24 +575,32 @@ struct v4l2_ext_control32 { }; } __attribute__ ((packed)); -/* The following function really belong in v4l2-common, but that causes - a circular dependency between modules. We need to think about this, but - for now this will do. */ - -/* Return non-zero if this control is a pointer type. Currently only - type STRING is a pointer type. */ -static inline int ctrl_is_pointer(u32 id) +/* Return true if this control is a pointer type. */ +static inline bool ctrl_is_pointer(struct file *file, u32 id) { - switch (id) { - case V4L2_CID_RDS_TX_PS_NAME: - case V4L2_CID_RDS_TX_RADIO_TEXT: - return 1; - default: - return 0; + struct video_device *vdev = video_devdata(file); + struct v4l2_fh *fh = NULL; + struct v4l2_ctrl_handler *hdl = NULL; + + if (test_bit(V4L2_FL_USES_V4L2_FH, &vdev->flags)) + fh = file->private_data; + + if (fh && fh->ctrl_handler) + hdl = fh->ctrl_handler; + else if (vdev->ctrl_handler) + hdl = vdev->ctrl_handler; + + if (hdl) { + struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, id); + + return ctrl && ctrl->type == V4L2_CTRL_TYPE_STRING; } + return false; } -static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext_controls32 __user *up) +static int get_v4l2_ext_controls32(struct file *file, + struct v4l2_ext_controls *kp, + struct v4l2_ext_controls32 __user *up) { struct v4l2_ext_control32 __user *ucontrols; struct v4l2_ext_control __user *kcontrols; @@ -621,7 +632,7 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext return -EFAULT; if (get_user(id, &kcontrols->id)) return -EFAULT; - if (ctrl_is_pointer(id)) { + if (ctrl_is_pointer(file, id)) { void __user *s; if (get_user(p, &ucontrols->string)) @@ -636,7 +647,9 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext return 0; } -static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext_controls32 __user *up) +static int put_v4l2_ext_controls32(struct file *file, + struct v4l2_ext_controls *kp, + struct v4l2_ext_controls32 __user *up) { struct v4l2_ext_control32 __user *ucontrols; struct v4l2_ext_control __user *kcontrols = @@ -668,7 +681,7 @@ static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext /* Do not modify the pointer when copying a pointer control. The contents of the pointer was changed, not the pointer itself. */ - if (ctrl_is_pointer(id)) + if (ctrl_is_pointer(file, id)) size -= sizeof(ucontrols->value64); if (copy_in_user(ucontrols, kcontrols, size)) return -EFAULT; @@ -832,7 +845,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar case VIDIOC_G_EXT_CTRLS: case VIDIOC_S_EXT_CTRLS: case VIDIOC_TRY_EXT_CTRLS: - err = get_v4l2_ext_controls32(&karg.v2ecs, up); + err = get_v4l2_ext_controls32(file, &karg.v2ecs, up); compatible_arg = 0; break; case VIDIOC_DQEVENT: @@ -859,7 +872,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar case VIDIOC_G_EXT_CTRLS: case VIDIOC_S_EXT_CTRLS: case VIDIOC_TRY_EXT_CTRLS: - if (put_v4l2_ext_controls32(&karg.v2ecs, up)) + if (put_v4l2_ext_controls32(file, &karg.v2ecs, up)) err = -EFAULT; break; } -- 2.30.2