[PATCH for v3.18 06/18] media: v4l2-compat-ioctl32.c: avoid sizeof(type)

From: Mauro Carvalho Chehab
Date: Wed Mar 28 2018 - 14:13:50 EST

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: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 80 +++++++++++++--------------
1 file changed, 38 insertions(+), 42 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index 702757012dc7..b7dd98168a68 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -47,7 +47,7 @@ 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) ||
@@ -64,7 +64,7 @@ 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)))
@@ -152,14 +152,14 @@ 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);
@@ -196,17 +196,17 @@ 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)) ||
- put_user(kp->type, &up->type))
+ 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)) ||
- copy_to_user(up, kp, offsetof(struct v4l2_create_buffers32, format.fmt)))
- return -EFAULT;
+ 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;
return __put_v4l2_format32(&kp->format, &up->format);
}

@@ -222,7 +222,7 @@ 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;
@@ -230,13 +230,13 @@ 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) ||
copy_to_user(up->id, &kp->id, sizeof(__u64)) ||
- 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;
}
@@ -284,7 +284,7 @@ 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) {
@@ -294,11 +294,11 @@ 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;
}

@@ -310,19 +310,19 @@ 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;
@@ -336,7 +336,7 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user
int num_planes;
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) ||
@@ -348,8 +348,7 @@ 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)) {
@@ -366,13 +365,12 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user

uplane32 = compat_ptr(p);
if (!access_ok(VERIFY_READ, uplane32,
- num_planes * sizeof(struct v4l2_plane32)))
+ num_planes * 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(num_planes *
- sizeof(struct v4l2_plane));
+ uplane = compat_alloc_user_space(num_planes * sizeof(*uplane));
kp->m.planes = (__force struct v4l2_plane *)uplane;

while (--num_planes >= 0) {
@@ -420,7 +418,7 @@ 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) ||
@@ -431,7 +429,7 @@ 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) ||
@@ -499,7 +497,7 @@ 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) ||
@@ -513,7 +511,7 @@ 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) ||
@@ -537,14 +535,14 @@ 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;
}
@@ -592,7 +590,7 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
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->ctrl_class, &up->ctrl_class) ||
get_user(kp->count, &up->count) ||
get_user(kp->error_idx, &up->error_idx) ||
@@ -606,10 +604,9 @@ 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,
- n * sizeof(struct v4l2_ext_control32)))
+ if (!access_ok(VERIFY_READ, ucontrols, n * sizeof(*ucontrols)))
return -EFAULT;
- kcontrols = compat_alloc_user_space(n * sizeof(struct v4l2_ext_control));
+ kcontrols = compat_alloc_user_space(n * sizeof(*kcontrols));
kp->controls = (__force struct v4l2_ext_control *)kcontrols;
while (--n >= 0) {
u32 id;
@@ -641,7 +638,7 @@ 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->ctrl_class, &up->ctrl_class) ||
put_user(kp->count, &up->count) ||
put_user(kp->error_idx, &up->error_idx) ||
@@ -653,8 +650,7 @@ 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) {
@@ -690,7 +686,7 @@ 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) ||
@@ -698,7 +694,7 @@ 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;
}
@@ -715,7 +711,7 @@ 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) ||
@@ -730,7 +726,7 @@ 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) ||
--
2.14.3