Em Wed, 18 Apr 2018 11:57:13 +0300 Sakari Ailus <sakari.ai...@linux.intel.com> escreveu:
> Hi Mauro, > > On Tue, Apr 17, 2018 at 10:25:37AM -0400, 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 <mche...@s-opensource.com> > > --- > > drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 40 > > ++++++++++++++++++--------- > > 1 file changed, 27 insertions(+), 13 deletions(-) > > > > diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > > b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c > > index 8c05dd9660d3..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);\ > > +}) > > I must say I like the approach. This makes it harder to get things wrong as > the compiler still does type checking. > > About the naming --- I understand the postfix comes from the modifier used > in the put_user case but in the others the same approach would lead to > names such as get_user_user() which would look a bit confusing. Yes. That's why I used _cast for the version that does the __user cast. > > I presume the patch depends on another patch from you. Yes, it comes after the p32/p64 rename. > Hans had comments on > that one that I think affect this one as well; This patch was added to address Hans comments on patch 4/5. Due to the renaming, folding it with patch 4/5 is not possible without big efforts. > could you add this one to > the same patchset? My plan is to apply all those 3 patches together after being reviewed. The 3 omap3 patches + the 3 ioctl32 patches are altogether here: https://git.linuxtv.org/mchehab/experimental.git/log/?h=compile_test_v6b > > > + > > + > > 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++) { > > @@ -898,12 +914,11 @@ 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, > > - (unsigned int __user *)&kcontrols->reserved2, > > + (void __user *)&kcontrols->reserved2, > > sizeof(ucontrols->reserved2))) > > return -EFAULT; > > > > @@ -916,7 +931,7 @@ static int put_v4l2_ext_controls32(struct file *file, > > size -= sizeof(ucontrols->value64); > > > > if (copy_in_user(ucontrols, > > - (unsigned int __user *)kcontrols, size)) > > + (void __user *)kcontrols, size)) > > return -EFAULT; > > > > ucontrols++; > > @@ -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, > > - (unsigned char __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; > > -- > > 2.14.3 > > > Thanks, Mauro
