Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 09c033b6 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
Browse files

media: v4l2-compat-ioctl32: simplify casts 

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/



Reviewed-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 6dd0394f

drivers/media/v4l2-core/v4l2-compat-ioctl32.c

+25 −11
Original line number Diff line number Diff line
@@ -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--) {
@@ -683,7 +700,7 @@ 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)))
@@ -832,8 +849,7 @@ 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++) {
@@ -899,10 +915,9 @@ 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)))
@@ -971,10 +986,9 @@ 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)))

		return -EFAULT;

	return 0;