media: v4l2-compat-ioctl32.c: avoid sizeof(type)

Instead of doing sizeof(struct foo) use sizeof(*up). There even were
cases where 4 * sizeof(__u32) was used instead of sizeof(kp->reserved),
which is very dangerous when the size of the reserved array changes.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 36 insertions, 43 deletions

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index c7e9d29d0e33..6c70705a48bc 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -48,7 +48,7 @@ struct v4l2_window32 {
 
 static int get_v4l2_window32(struct v4l2_window *kp, struct v4l2_window32 __user *up)
 {
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_window32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             copy_from_user(&kp->w, &up->w, sizeof(up->w)) ||
             get_user(kp->field, &up->field) ||
             get_user(kp->chromakey, &up->chromakey) ||
@@ -66,7 +66,7 @@ static int get_v4l2_window32(struct v4l2_window *kp, struct v4l2_window32 __user
                 if (get_user(p, &up->clips))
                         return -EFAULT;
                 uclips = compat_ptr(p);
-                kclips = compat_alloc_user_space(n * sizeof(struct v4l2_clip));
+                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)))
@@ -164,14 +164,14 @@ static int __get_v4l2_format32(struct v4l2_format *kp, struct v4l2_format32 __us
 
 static int get_v4l2_format32(struct v4l2_format *kp, struct v4l2_format32 __user *up)
 {
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_format32)))
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)))
                 return -EFAULT;
         return __get_v4l2_format32(kp, up);
 }
 
 static int get_v4l2_create32(struct v4l2_create_buffers *kp, struct v4l2_create_buffers32 __user *up)
 {
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_create_buffers32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             copy_from_user(kp, up, offsetof(struct v4l2_create_buffers32, format)))
                 return -EFAULT;
         return __get_v4l2_format32(&kp->format, &up->format);
@@ -218,14 +218,14 @@ static int __put_v4l2_format32(struct v4l2_format *kp, struct v4l2_format32 __us
 
 static int put_v4l2_format32(struct v4l2_format *kp, struct v4l2_format32 __user *up)
 {
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_format32)))
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
                 return -EFAULT;
         return __put_v4l2_format32(kp, up);
 }
 
 static int put_v4l2_create32(struct v4l2_create_buffers *kp, struct v4l2_create_buffers32 __user *up)
 {
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_create_buffers32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             copy_to_user(up, kp, offsetof(struct v4l2_create_buffers32, format)) ||
             copy_to_user(up->reserved, kp->reserved, sizeof(kp->reserved)))
                 return -EFAULT;
@@ -244,7 +244,7 @@ struct v4l2_standard32 {
 static int get_v4l2_standard32(struct v4l2_standard *kp, struct v4l2_standard32 __user *up)
 {
         /* other fields are not set by the user, nor used by the driver */
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_standard32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             get_user(kp->index, &up->index))
                 return -EFAULT;
         return 0;
@@ -252,14 +252,14 @@ static int get_v4l2_standard32(struct v4l2_standard *kp, struct v4l2_standard32
 
 static int put_v4l2_standard32(struct v4l2_standard *kp, struct v4l2_standard32 __user *up)
 {
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_standard32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(kp->index, &up->index) ||
             put_user(kp->id, &up->id) ||
-            copy_to_user(up->name, kp->name, 24) ||
+            copy_to_user(up->name, kp->name, sizeof(up->name)) ||
             copy_to_user(&up->frameperiod, &kp->frameperiod,
                          sizeof(kp->frameperiod)) ||
             put_user(kp->framelines, &up->framelines) ||
-            copy_to_user(up->reserved, kp->reserved, 4 * sizeof(__u32)))
+            copy_to_user(up->reserved, kp->reserved, sizeof(kp->reserved)))
                 return -EFAULT;
         return 0;
 }
@@ -307,7 +307,7 @@ static int get_v4l2_plane32(struct v4l2_plane __user *up, struct v4l2_plane32 __
 
         if (copy_in_user(up, up32, 2 * sizeof(__u32)) ||
             copy_in_user(&up->data_offset, &up32->data_offset,
-                         sizeof(__u32)))
+                         sizeof(up->data_offset)))
                 return -EFAULT;
 
         if (memory == V4L2_MEMORY_USERPTR) {
@@ -317,11 +317,11 @@ static int get_v4l2_plane32(struct v4l2_plane __user *up, struct v4l2_plane32 __
                 if (put_user((unsigned long)up_pln, &up->m.userptr))
                         return -EFAULT;
         } else if (memory == V4L2_MEMORY_DMABUF) {
-                if (copy_in_user(&up->m.fd, &up32->m.fd, sizeof(int)))
+                if (copy_in_user(&up->m.fd, &up32->m.fd, sizeof(up32->m.fd)))
                         return -EFAULT;
         } else {
                 if (copy_in_user(&up->m.mem_offset, &up32->m.mem_offset,
-                                 sizeof(__u32)))
+                                 sizeof(up32->m.mem_offset)))
                         return -EFAULT;
         }
 
@@ -333,19 +333,19 @@ static int put_v4l2_plane32(struct v4l2_plane __user *up, struct v4l2_plane32 __
 {
         if (copy_in_user(up32, up, 2 * sizeof(__u32)) ||
             copy_in_user(&up32->data_offset, &up->data_offset,
-                         sizeof(__u32)))
+                         sizeof(up->data_offset)))
                 return -EFAULT;
 
         /* For MMAP, driver might've set up the offset, so copy it back.
          * USERPTR stays the same (was userspace-provided), so no copying. */
         if (memory == V4L2_MEMORY_MMAP)
                 if (copy_in_user(&up32->m.mem_offset, &up->m.mem_offset,
-                                 sizeof(__u32)))
+                                 sizeof(up->m.mem_offset)))
                         return -EFAULT;
         /* For DMABUF, driver might've set up the fd, so copy it back. */
         if (memory == V4L2_MEMORY_DMABUF)
                 if (copy_in_user(&up32->m.fd, &up->m.fd,
-                                 sizeof(int)))
+                                 sizeof(up->m.fd)))
                         return -EFAULT;
 
         return 0;
@@ -358,7 +358,7 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
         compat_caddr_t p;
         int ret;
 
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_buffer32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             get_user(kp->index, &up->index) ||
             get_user(kp->type, &up->type) ||
             get_user(kp->flags, &up->flags) ||
@@ -370,8 +370,7 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
                 if (get_user(kp->bytesused, &up->bytesused) ||
                     get_user(kp->field, &up->field) ||
                     get_user(kp->timestamp.tv_sec, &up->timestamp.tv_sec) ||
-                    get_user(kp->timestamp.tv_usec,
-                             &up->timestamp.tv_usec))
+                    get_user(kp->timestamp.tv_usec, &up->timestamp.tv_usec))
                         return -EFAULT;
 
         if (V4L2_TYPE_IS_MULTIPLANAR(kp->type)) {
@@ -391,13 +390,12 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
 
                 uplane32 = compat_ptr(p);
                 if (!access_ok(VERIFY_READ, uplane32,
-                               kp->length * sizeof(struct v4l2_plane32)))
+                               kp->length * sizeof(*uplane32)))
                         return -EFAULT;
 
                 /* We don't really care if userspace decides to kill itself
                  * by passing a very big num_planes value */
-                uplane = compat_alloc_user_space(kp->length *
-                                                 sizeof(struct v4l2_plane));
+                uplane = compat_alloc_user_space(kp->length * sizeof(*uplane));
                 kp->m.planes = (__force struct v4l2_plane *)uplane;
 
                 for (num_planes = 0; num_planes < kp->length; num_planes++) {
@@ -445,7 +443,7 @@ static int put_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
         int num_planes;
         int ret;
 
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_buffer32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(kp->index, &up->index) ||
             put_user(kp->type, &up->type) ||
             put_user(kp->flags, &up->flags) ||
@@ -456,8 +454,7 @@ static int put_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
             put_user(kp->field, &up->field) ||
             put_user(kp->timestamp.tv_sec, &up->timestamp.tv_sec) ||
             put_user(kp->timestamp.tv_usec, &up->timestamp.tv_usec) ||
-            copy_to_user(&up->timecode, &kp->timecode,
-                         sizeof(struct v4l2_timecode)) ||
+            copy_to_user(&up->timecode, &kp->timecode, sizeof(kp->timecode)) ||
             put_user(kp->sequence, &up->sequence) ||
             put_user(kp->reserved2, &up->reserved2) ||
             put_user(kp->reserved, &up->reserved) ||
@@ -525,7 +522,7 @@ static int get_v4l2_framebuffer32(struct v4l2_framebuffer *kp, struct v4l2_frame
 {
         u32 tmp;
 
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_framebuffer32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             get_user(tmp, &up->base) ||
             get_user(kp->capability, &up->capability) ||
             get_user(kp->flags, &up->flags) ||
@@ -539,7 +536,7 @@ static int put_v4l2_framebuffer32(struct v4l2_framebuffer *kp, struct v4l2_frame
 {
         u32 tmp = (u32)((unsigned long)kp->base);
 
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_framebuffer32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(tmp, &up->base) ||
             put_user(kp->capability, &up->capability) ||
             put_user(kp->flags, &up->flags) ||
@@ -564,14 +561,14 @@ struct v4l2_input32 {
    Otherwise it is identical to the 32-bit version. */
 static inline int get_v4l2_input32(struct v4l2_input *kp, struct v4l2_input32 __user *up)
 {
-        if (copy_from_user(kp, up, sizeof(struct v4l2_input32)))
+        if (copy_from_user(kp, up, sizeof(*up)))
                 return -EFAULT;
         return 0;
 }
 
 static inline int put_v4l2_input32(struct v4l2_input *kp, struct v4l2_input32 __user *up)
 {
-        if (copy_to_user(up, kp, sizeof(struct v4l2_input32)))
+        if (copy_to_user(up, kp, sizeof(*up)))
                 return -EFAULT;
         return 0;
 }
@@ -619,12 +616,11 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
         unsigned int n;
         compat_caddr_t p;
 
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_ext_controls32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             get_user(kp->which, &up->which) ||
             get_user(kp->count, &up->count) ||
             get_user(kp->error_idx, &up->error_idx) ||
-            copy_from_user(kp->reserved, up->reserved,
-                           sizeof(kp->reserved)))
+            copy_from_user(kp->reserved, up->reserved, sizeof(kp->reserved)))
                 return -EFAULT;
         if (kp->count == 0) {
                 kp->controls = NULL;
@@ -635,11 +631,9 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
         if (get_user(p, &up->controls))
                 return -EFAULT;
         ucontrols = compat_ptr(p);
-        if (!access_ok(VERIFY_READ, ucontrols,
-                       kp->count * sizeof(struct v4l2_ext_control32)))
+        if (!access_ok(VERIFY_READ, ucontrols, kp->count * sizeof(*ucontrols)))
                 return -EFAULT;
-        kcontrols = compat_alloc_user_space(kp->count *
-                                            sizeof(struct v4l2_ext_control));
+        kcontrols = compat_alloc_user_space(kp->count * sizeof(*kcontrols));
         kp->controls = (__force struct v4l2_ext_control *)kcontrols;
         for (n = 0; n < kp->count; n++) {
                 u32 id;
@@ -671,7 +665,7 @@ static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
         int n = kp->count;
         compat_caddr_t p;
 
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_ext_controls32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(kp->which, &up->which) ||
             put_user(kp->count, &up->count) ||
             put_user(kp->error_idx, &up->error_idx) ||
@@ -683,8 +677,7 @@ static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
         if (get_user(p, &up->controls))
                 return -EFAULT;
         ucontrols = compat_ptr(p);
-        if (!access_ok(VERIFY_WRITE, ucontrols,
-                       n * sizeof(struct v4l2_ext_control32)))
+        if (!access_ok(VERIFY_WRITE, ucontrols, n * sizeof(*ucontrols)))
                 return -EFAULT;
 
         while (--n >= 0) {
@@ -721,7 +714,7 @@ struct v4l2_event32 {
 
 static int put_v4l2_event32(struct v4l2_event *kp, struct v4l2_event32 __user *up)
 {
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_event32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(kp->type, &up->type) ||
             copy_to_user(&up->u, &kp->u, sizeof(kp->u)) ||
             put_user(kp->pending, &up->pending) ||
@@ -729,7 +722,7 @@ static int put_v4l2_event32(struct v4l2_event *kp, struct v4l2_event32 __user *u
             put_user(kp->timestamp.tv_sec, &up->timestamp.tv_sec) ||
             put_user(kp->timestamp.tv_nsec, &up->timestamp.tv_nsec) ||
             put_user(kp->id, &up->id) ||
-            copy_to_user(up->reserved, kp->reserved, 8 * sizeof(__u32)))
+            copy_to_user(up->reserved, kp->reserved, sizeof(kp->reserved)))
                 return -EFAULT;
         return 0;
 }
@@ -746,7 +739,7 @@ static int get_v4l2_edid32(struct v4l2_edid *kp, struct v4l2_edid32 __user *up)
 {
         u32 tmp;
 
-        if (!access_ok(VERIFY_READ, up, sizeof(struct v4l2_edid32)) ||
+        if (!access_ok(VERIFY_READ, up, sizeof(*up)) ||
             get_user(kp->pad, &up->pad) ||
             get_user(kp->start_block, &up->start_block) ||
             get_user(kp->blocks, &up->blocks) ||
@@ -761,7 +754,7 @@ static int put_v4l2_edid32(struct v4l2_edid *kp, struct v4l2_edid32 __user *up)
 {
         u32 tmp = (u32)((unsigned long)kp->edid);
 
-        if (!access_ok(VERIFY_WRITE, up, sizeof(struct v4l2_edid32)) ||
+        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)) ||
             put_user(kp->pad, &up->pad) ||
             put_user(kp->start_block, &up->start_block) ||
             put_user(kp->blocks, &up->blocks) ||