[PATCH 4.15 119/202] media: v4l2-compat-ioctl32.c: avoid sizeof(type)

From: Greg Kroah-Hartman
Date: Thu Feb 15 2018 - 11:17:51 EST

4.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Hans Verkuil <hans.verkuil@xxxxxxxxx>

commit 333b1e9f96ce05f7498b581509bb30cde03018bf upstream.

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>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 79 +++++++++++---------------
1 file changed, 36 insertions(+), 43 deletions(-)

--- 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
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 v4

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 v4

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 v4

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_

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_
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_
{
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
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
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

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
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
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
{
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
{
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(struc
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(struc
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(struc
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(struc
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_
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_e
{
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_e
{
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) ||