[PATCH 3.2 135/140] media: v4l2-compat-ioctl32.c: copy clip list in put_v4l2_window32

Ben Hutchings
2018-02-28T17:44:43Z

From: Hans Verkuil <hans.verkuil@cisco.com>

commit a751be5b142ef6bcbbb96d9899516f4d9c8d0ef4 upstream.

put_v4l2_window32() didn't copy back the clip list to userspace.
Drivers can update the clip rectangles, so this should be done.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/media/video/v4l2-compat-ioctl32.c | 59 +++++++++++++++++++++----------
1 file changed, 40 insertions(+), 19 deletions(-)

--- a/drivers/media/video/v4l2-compat-ioctl32.c
+++ b/drivers/media/video/v4l2-compat-ioctl32.c
@@ -51,6 +51,11 @@ struct v4l2_window32 {

static int get_v4l2_window32(struct v4l2_window *kp, struct v4l2_window32 __user *up)
{
+ struct v4l2_clip32 __user *uclips;
+ struct v4l2_clip __user *kclips;
+ compat_caddr_t p;
+ u32 n;
+
if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
copy_from_user(&kp->w, &up->w, sizeof(up->w)) ||
get_user(kp->field, &up->field) ||
@@ -60,38 +65,54 @@ static int get_v4l2_window32(struct v4l2
return -EFAULT;
if (kp->clipcount > 2048)
return -EINVAL;
- if (kp->clipcount) {
- struct v4l2_clip32 __user *uclips;
- struct v4l2_clip __user *kclips;
- int n = kp->clipcount;
- compat_caddr_t p;
+ if (!kp->clipcount) {
+ kp->clips = NULL;
+ return 0;
+ }

- if (get_user(p, &up->clips))
+ n = kp->clipcount;
+ if (get_user(p, &up->clips))
+ return -EFAULT;
+ uclips = compat_ptr(p);
+ kclips = compat_alloc_user_space(n * sizeof(*kclips));
+ kp->clips = kclips;
+ while (n--) {
+ if (copy_in_user(&kclips->c, &uclips->c, sizeof(uclips->c)))
return -EFAULT;
- uclips = compat_ptr(p);
- kclips = compat_alloc_user_space(n * sizeof(*kclips));
- kp->clips = kclips;
- while (--n >= 0) {
- if (copy_in_user(&kclips->c, &uclips->c, sizeof(uclips->c)))
- return -EFAULT;
- if (put_user(n ? kclips + 1 : NULL, &kclips->next))
- return -EFAULT;
- uclips += 1;
- kclips += 1;
- }
- } else
- kp->clips = NULL;
+ if (put_user(n ? kclips + 1 : NULL, &kclips->next))
+ return -EFAULT;
+ uclips++;
+ kclips++;
+ }
return 0;
}

static int put_v4l2_window32(struct v4l2_window *kp, struct v4l2_window32 __user *up)
{
+ struct v4l2_clip __user *kclips = kp->clips;
+ struct v4l2_clip32 __user *uclips;
+ u32 n = kp->clipcount;
+ compat_caddr_t p;
+
if (copy_to_user(&up->w, &kp->w, sizeof(kp->w)) ||
put_user(kp->field, &up->field) ||
put_user(kp->chromakey, &up->chromakey) ||
put_user(kp->clipcount, &up->clipcount) ||
put_user(kp->global_alpha, &up->global_alpha))
return -EFAULT;
+
+ if (!kp->clipcount)
+ return 0;
+
+ if (get_user(p, &up->clips))
+ return -EFAULT;
+ uclips = compat_ptr(p);
+ while (n--) {
+ if (copy_in_user(&uclips->c, &kclips->c, sizeof(uclips->c)))
+ return -EFAULT;
+ uclips++;
+ kclips++;
+ }
return 0;
}