On Fri, Jan 26, 2018 at 01:43:21PM +0100, Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>
> 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@xxxxxxxxx>
Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 77 ++++++++++++---------------
> 1 file changed, 35 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> index 2dd9b42d5859..809448d1b7db 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->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) ||
> --
> 2.15.1
>
--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx
