[PATCH v2 3/4] media: v4l2-compat-ioctl32: simplify casts

2018-04-19 Thread Mauro Carvalho Chehab
Making the cast right for get_user/put_user is not trivial, as
it needs to ensure that the types are the correct ones.

Improve it by using macros.

Tested with vivid with:
$ sudo modprobe vivid no_error_inj=1
$ v4l2-compliance-32bits -a -s10 >32bits && v4l2-compliance-64bits -a 
-s10 > 64bits && diff -U0 32bits 64bits
--- 32bits  2018-04-17 11:18:29.141240772 -0300
+++ 64bits  2018-04-17 11:18:40.635282341 -0300
@@ -1 +1 @@
-v4l2-compliance SHA   : bc71e4a67c6fbc5940062843bc41e7c8679634ce, 32 
bits
+v4l2-compliance SHA   : bc71e4a67c6fbc5940062843bc41e7c8679634ce, 64 
bits

Using the latest version of v4l-utils with this patch applied:
https://patchwork.linuxtv.org/patch/48746/

Signed-off-by: Mauro Carvalho Chehab 
---
 drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 36 +++
 1 file changed, 25 insertions(+), 11 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c 
b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index 680b64c1d69a..d2f0268427c2 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -30,6 +30,24 @@
get_user(__assign_tmp, from) || put_user(__assign_tmp, to); \
 })
 
+#define get_user_cast(__x, __ptr)  \
+({ \
+   get_user(__x, (typeof(*__ptr) __user *)(__ptr));\
+})
+
+#define put_user_force(__x, __ptr) \
+({ \
+   put_user((typeof(*__x) __force *)(__x), __ptr); \
+})
+
+#define assign_in_user_cast(to, from)  \
+({ \
+   typeof(*from) __assign_tmp; \
+   \
+   get_user_cast(__assign_tmp, from) || put_user(__assign_tmp, to);\
+})
+
+
 static long native_ioctl(struct file *file, unsigned int cmd, unsigned long 
arg)
 {
long ret = -ENOIOCTLCMD;
@@ -543,8 +561,7 @@ static int get_v4l2_buffer32(struct v4l2_buffer __user *p64,
return -EFAULT;
 
uplane = aux_buf;
-   if (put_user((__force struct v4l2_plane *)uplane,
-&p64->m.planes))
+   if (put_user_force(uplane, &p64->m.planes))
return -EFAULT;
 
while (num_planes--) {
@@ -682,7 +699,7 @@ static int get_v4l2_framebuffer32(struct v4l2_framebuffer 
__user *p64,
 
if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
get_user(tmp, &p32->base) ||
-   put_user((void __force *)compat_ptr(tmp), &p64->base) ||
+   put_user_force(compat_ptr(tmp), &p64->base) ||
assign_in_user(&p64->capability, &p32->capability) ||
assign_in_user(&p64->flags, &p32->flags) ||
copy_in_user(&p64->fmt, &p32->fmt, sizeof(p64->fmt)))
@@ -831,8 +848,7 @@ static int get_v4l2_ext_controls32(struct file *file,
if (aux_space < count * sizeof(*kcontrols))
return -EFAULT;
kcontrols = aux_buf;
-   if (put_user((__force struct v4l2_ext_control *)kcontrols,
-&p64->controls))
+   if (put_user_force(kcontrols, &p64->controls))
return -EFAULT;
 
for (n = 0; n < count; n++) {
@@ -898,10 +914,9 @@ static int put_v4l2_ext_controls32(struct file *file,
unsigned int size = sizeof(*ucontrols);
u32 id;
 
-   if (get_user(id, (unsigned int __user *)&kcontrols->id) ||
+   if (get_user_cast(id, &kcontrols->id) ||
put_user(id, &ucontrols->id) ||
-   assign_in_user(&ucontrols->size,
-  (unsigned int __user *)&kcontrols->size) ||
+   assign_in_user_cast(&ucontrols->size, &kcontrols->size) ||
copy_in_user(&ucontrols->reserved2,
 (void __user *)&kcontrols->reserved2,
 sizeof(ucontrols->reserved2)))
@@ -970,10 +985,9 @@ static int get_v4l2_edid32(struct v4l2_edid __user *p64,
if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
assign_in_user(&p64->pad, &p32->pad) ||
assign_in_user(&p64->start_block, &p32->start_block) ||
-   assign_in_user(&p64->blocks,
-  (u32 __user *)&p32->blocks) ||
+   assign_in_user_cast(&p64->blocks, &p32->blocks) ||
get_user(tmp, &p32->edid) ||
-   put_user((void __force *)compat_ptr(tmp), &p64->edid) ||
+   put_user_force(compat_ptr(tmp), &p64->edid) ||
copy_in_user(p64->reserved, p32->reserved, sizeof(p64->reserved)))
 

Re: [PATCH v2 3/4] media: v4l2-compat-ioctl32: simplify casts

2018-04-20 Thread Hans Verkuil
On 04/19/18 18:33, Mauro Carvalho Chehab wrote:
> Making the cast right for get_user/put_user is not trivial, as
> it needs to ensure that the types are the correct ones.
> 
> Improve it by using macros.
> 
> Tested with vivid with:
>   $ sudo modprobe vivid no_error_inj=1
>   $ v4l2-compliance-32bits -a -s10 >32bits && v4l2-compliance-64bits -a 
> -s10 > 64bits && diff -U0 32bits 64bits
>   --- 32bits  2018-04-17 11:18:29.141240772 -0300
>   +++ 64bits  2018-04-17 11:18:40.635282341 -0300
>   @@ -1 +1 @@
>   -v4l2-compliance SHA   : bc71e4a67c6fbc5940062843bc41e7c8679634ce, 32 
> bits
>   +v4l2-compliance SHA   : bc71e4a67c6fbc5940062843bc41e7c8679634ce, 64 
> bits
> 
> Using the latest version of v4l-utils with this patch applied:
>   https://patchwork.linuxtv.org/patch/48746/
> 
> Signed-off-by: Mauro Carvalho Chehab 

Reviewed-by: Hans Verkuil 

Regards,

Hans

> ---
>  drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 36 
> +++
>  1 file changed, 25 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c 
> b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> index 680b64c1d69a..d2f0268427c2 100644
> --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> @@ -30,6 +30,24 @@
>   get_user(__assign_tmp, from) || put_user(__assign_tmp, to); \
>  })
>  
> +#define get_user_cast(__x, __ptr)\
> +({   \
> + get_user(__x, (typeof(*__ptr) __user *)(__ptr));\
> +})
> +
> +#define put_user_force(__x, __ptr)   \
> +({   \
> + put_user((typeof(*__x) __force *)(__x), __ptr); \
> +})
> +
> +#define assign_in_user_cast(to, from)
> \
> +({   \
> + typeof(*from) __assign_tmp; \
> + \
> + get_user_cast(__assign_tmp, from) || put_user(__assign_tmp, to);\
> +})
> +
> +
>  static long native_ioctl(struct file *file, unsigned int cmd, unsigned long 
> arg)
>  {
>   long ret = -ENOIOCTLCMD;
> @@ -543,8 +561,7 @@ static int get_v4l2_buffer32(struct v4l2_buffer __user 
> *p64,
>   return -EFAULT;
>  
>   uplane = aux_buf;
> - if (put_user((__force struct v4l2_plane *)uplane,
> -  &p64->m.planes))
> + if (put_user_force(uplane, &p64->m.planes))
>   return -EFAULT;
>  
>   while (num_planes--) {
> @@ -682,7 +699,7 @@ static int get_v4l2_framebuffer32(struct v4l2_framebuffer 
> __user *p64,
>  
>   if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
>   get_user(tmp, &p32->base) ||
> - put_user((void __force *)compat_ptr(tmp), &p64->base) ||
> + put_user_force(compat_ptr(tmp), &p64->base) ||
>   assign_in_user(&p64->capability, &p32->capability) ||
>   assign_in_user(&p64->flags, &p32->flags) ||
>   copy_in_user(&p64->fmt, &p32->fmt, sizeof(p64->fmt)))
> @@ -831,8 +848,7 @@ static int get_v4l2_ext_controls32(struct file *file,
>   if (aux_space < count * sizeof(*kcontrols))
>   return -EFAULT;
>   kcontrols = aux_buf;
> - if (put_user((__force struct v4l2_ext_control *)kcontrols,
> -  &p64->controls))
> + if (put_user_force(kcontrols, &p64->controls))
>   return -EFAULT;
>  
>   for (n = 0; n < count; n++) {
> @@ -898,10 +914,9 @@ static int put_v4l2_ext_controls32(struct file *file,
>   unsigned int size = sizeof(*ucontrols);
>   u32 id;
>  
> - if (get_user(id, (unsigned int __user *)&kcontrols->id) ||
> + if (get_user_cast(id, &kcontrols->id) ||
>   put_user(id, &ucontrols->id) ||
> - assign_in_user(&ucontrols->size,
> -(unsigned int __user *)&kcontrols->size) ||
> + assign_in_user_cast(&ucontrols->size, &kcontrols->size) ||
>   copy_in_user(&ucontrols->reserved2,
>(void __user *)&kcontrols->reserved2,
>sizeof(ucontrols->reserved2)))
> @@ -970,10 +985,9 @@ static int get_v4l2_edid32(struct v4l2_edid __user *p64,
>   if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
>   assign_in_user(&p64->pad, &p32->pad) ||
>   assign_in_user(&p64->start_block, &p32->start_block) ||
> - assign_in_user(&p64->blocks,
> -(u32 __user *)&p32->blocks) ||
> + assign_in_user_cast(&p64->blocks, &p32->blocks) ||
>   get_user(tmp, &p32->edid) ||
> -