media: v4l2-compat-ioctl32: fix several __user annotations

Smatch report several issues with bad __user annotations:

  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:447:21: warning: incorrect type in argument 1 (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:447:21:    expected void [noderef] <asn:1>*uptr
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:447:21:    got void *<noident>
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:621:21: warning: incorrect type in argument 1 (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:621:21:    expected void const volatile [noderef] <asn:1>*<noident>
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:621:21:    got struct v4l2_plane [noderef] <asn:1>**<noident>
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:693:13: warning: incorrect type in argument 1 (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:693:13:    expected void [noderef] <asn:1>*uptr
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:693:13:    got void *[assigned] base
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:871:13: warning: incorrect type in assignment (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:871:13:    expected struct v4l2_ext_control [noderef] <asn:1>*kcontrols
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:871:13:    got struct v4l2_ext_control *<noident>
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:957:13: warning: incorrect type in assignment (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:957:13:    expected unsigned char [usertype] *__pu_val
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:957:13:    got void [noderef] <asn:1>*
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:973:13: warning: incorrect type in argument 1 (different address spaces)
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:973:13:    expected void [noderef] <asn:1>*uptr
  drivers/media/v4l2-core/v4l2-compat-ioctl32.c:973:13:    got void *[assigned] edid

Fix them.

Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index d03a44d896495953e2d914c67bca87284f640ada..aaf37af1612bec5584cdfbfb692afea5046b778a 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -444,7 +444,7 @@ static int put_v4l2_plane32(struct v4l2_plane __user *up,
                break;
        case V4L2_MEMORY_USERPTR:
                if (get_user(p, &up->m.userptr) ||
-                   put_user((compat_ulong_t)ptr_to_compat((__force void *)p),
+                   put_user((compat_ulong_t)ptr_to_compat((void __user *)p),
                             &up32->m.userptr))
                        return -EFAULT;
                break;
@@ -587,7 +587,7 @@ static int put_v4l2_buffer32(struct v4l2_buffer __user *kp,
        u32 length;
        enum v4l2_memory memory;
        struct v4l2_plane32 __user *uplane32;
-       struct v4l2_plane __user *uplane;
+       struct v4l2_plane *uplane;
        compat_caddr_t p;
        int ret;
 
@@ -617,15 +617,23 @@ static int put_v4l2_buffer32(struct v4l2_buffer __user *kp,
 
                if (num_planes == 0)
                        return 0;
-
-               if (get_user(uplane, ((__force struct v4l2_plane __user **)&kp->m.planes)))
+               /* We need to define uplane without __user, even though
+                * it does point to data in userspace here. The reason is
+                * that v4l2-ioctl.c copies it from userspace to kernelspace,
+                * so its definition in videodev2.h doesn't have a
+                * __user markup. Defining uplane with __user causes
+                * smatch warnings, so instead declare it without __user
+                * and cast it as a userspace pointer to put_v4l2_plane32().
+                */
+               if (get_user(uplane, &kp->m.planes))
                        return -EFAULT;
                if (get_user(p, &up->m.planes))
                        return -EFAULT;
                uplane32 = compat_ptr(p);
 
                while (num_planes--) {
-                       ret = put_v4l2_plane32(uplane, uplane32, memory);
+                       ret = put_v4l2_plane32((void __user *)uplane,
+                                              uplane32, memory);
                        if (ret)
                                return ret;
                        ++uplane;
@@ -675,7 +683,7 @@ static int get_v4l2_framebuffer32(struct v4l2_framebuffer __user *kp,
 
        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
            get_user(tmp, &up->base) ||
-           put_user((__force void *)compat_ptr(tmp), &kp->base) ||
+           put_user((void __force *)compat_ptr(tmp), &kp->base) ||
            assign_in_user(&kp->capability, &up->capability) ||
            assign_in_user(&kp->flags, &up->flags) ||
            copy_in_user(&kp->fmt, &up->fmt, sizeof(kp->fmt)))
@@ -690,7 +698,7 @@ static int put_v4l2_framebuffer32(struct v4l2_framebuffer __user *kp,
 
        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
            get_user(base, &kp->base) ||
-           put_user(ptr_to_compat(base), &up->base) ||
+           put_user(ptr_to_compat((void __user *)base), &up->base) ||
            assign_in_user(&up->capability, &kp->capability) ||
            assign_in_user(&up->flags, &kp->flags) ||
            copy_in_user(&up->fmt, &kp->fmt, sizeof(kp->fmt)))
@@ -857,11 +865,19 @@ static int put_v4l2_ext_controls32(struct file *file,
                                   struct v4l2_ext_controls32 __user *up)
 {
        struct v4l2_ext_control32 __user *ucontrols;
-       struct v4l2_ext_control __user *kcontrols;
+       struct v4l2_ext_control *kcontrols;
        u32 count;
        u32 n;
        compat_caddr_t p;
 
+       /*
+        * We need to define kcontrols without __user, even though it does
+        * point to data in userspace here. The reason is that v4l2-ioctl.c
+        * copies it from userspace to kernelspace, so its definition in
+        * videodev2.h doesn't have a __user markup. Defining kcontrols
+        * with __user causes smatch warnings, so instead declare it
+        * without __user and cast it as a userspace pointer where needed.
+        */
        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
            assign_in_user(&up->which, &kp->which) ||
            get_user(count, &kp->count) ||
@@ -883,10 +899,12 @@ static int put_v4l2_ext_controls32(struct file *file,
                unsigned int size = sizeof(*ucontrols);
                u32 id;
 
-               if (get_user(id, &kcontrols->id) ||
+               if (get_user(id, (unsigned int __user *)&kcontrols->id) ||
                    put_user(id, &ucontrols->id) ||
-                   assign_in_user(&ucontrols->size, &kcontrols->size) ||
-                   copy_in_user(&ucontrols->reserved2, &kcontrols->reserved2,
+                   assign_in_user(&ucontrols->size,
+                                  (unsigned int __user *)&kcontrols->size) ||
+                   copy_in_user(&ucontrols->reserved2,
+                                (void __user *)&kcontrols->reserved2,
                                 sizeof(ucontrols->reserved2)))
                        return -EFAULT;
 
@@ -898,7 +916,8 @@ static int put_v4l2_ext_controls32(struct file *file,
                if (ctrl_is_pointer(file, id))
                        size -= sizeof(ucontrols->value64);
 
-               if (copy_in_user(ucontrols, kcontrols, size))
+               if (copy_in_user(ucontrols,
+                                (void __user *)kcontrols, size))
                        return -EFAULT;
 
                ucontrols++;
@@ -952,9 +971,10 @@ static int get_v4l2_edid32(struct v4l2_edid __user *kp,
        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
            assign_in_user(&kp->pad, &up->pad) ||
            assign_in_user(&kp->start_block, &up->start_block) ||
-           assign_in_user(&kp->blocks, &up->blocks) ||
+           assign_in_user(&kp->blocks,
+                          (u32 __user *)&up->blocks) ||
            get_user(tmp, &up->edid) ||
-           put_user(compat_ptr(tmp), &kp->edid) ||
+           put_user((void __force *)compat_ptr(tmp), &kp->edid) ||
            copy_in_user(kp->reserved, up->reserved, sizeof(kp->reserved)))
                return -EFAULT;
        return 0;
@@ -970,7 +990,7 @@ static int put_v4l2_edid32(struct v4l2_edid __user *kp,
            assign_in_user(&up->start_block, &kp->start_block) ||
            assign_in_user(&up->blocks, &kp->blocks) ||
            get_user(edid, &kp->edid) ||
-           put_user(ptr_to_compat(edid), &up->edid) ||
+           put_user(ptr_to_compat((void __user *)edid), &up->edid) ||
            copy_in_user(up->reserved, kp->reserved, sizeof(up->reserved)))
                return -EFAULT;
        return 0;