Re: [RFC PATCH v1 7/9] x86: Add unsafe_copy_from_user()
Usama Arif <[email protected]> Wed, 29 Apr 2026 03:25:19 -0700
| Newsgroups | gmane.linux.x25,gmane.linux.ports.alpha,gmane.linux.kernel,gmane.linux.kernel.arc,gmane.linux.ports.arm.kernel,gmane.linux.ports.mips,gmane.linux.ports.ppc64.devel,gmane.comp.emulators.kvm.devel,gmane.linux.ports.riscv,gmane.linux.ports.sparc,gmane.linux.uml.devel,gmane.linux.kernel.efi,gmane.comp.freedesktop.amd-gfx,gmane.comp.video.dri.devel,gmane.comp.freedesktop.xorg.drivers.intel,gmane.linux.network,gmane.linux.kernel.wireless.general,gmane.linux.kernel.spi.devel,gmane.linux.drivers.video-input-infrastructure,gmane.linux.serial,gmane.linux.usb.general,gmane.comp.emulators.xen.devel,gmane.linux.file-systems,gmane.linux.kernel.bpf,gmane.linux.kernel.mm,gmane.linux.kernel.rust,gmane.linux.sound,gmane.linux.ports.hexagon,gmane.linux.ports.parisc,gmane.linux.ports.sh.devel,gmane.linux.kernel.cross-arch |
|---|---|
| Message-ID | <[email protected]> |
On Mon, 27 Apr 2026 19:13:48 +0200 "Christophe Leroy (CS GROUP)" <[email protected]> wrote: > At the time being, x86 and arm64 are missing unsafe_copy_from_user(). > > Add it. > > Signed-off-by: Christophe Leroy (CS GROUP) <[email protected]> > --- > arch/x86/include/asm/uaccess.h | 29 ++++++++++++++++++++++++----- > 1 file changed, 24 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h > index 3a0dd3c2b233..10c458ffa399 100644 > --- a/arch/x86/include/asm/uaccess.h > +++ b/arch/x86/include/asm/uaccess.h > @@ -598,7 +598,7 @@ _label: \ > * We want the unsafe accessors to always be inlined and use > * the error labels - thus the macro games. > */ > -#define unsafe_copy_loop(dst, src, len, type, label) \ > +#define unsafe_put_loop(dst, src, len, type, label) \ > while (len >= sizeof(type)) { \ > unsafe_put_user(*(type *)(src),(type __user *)(dst),label); \ > dst += sizeof(type); \ > @@ -611,10 +611,29 @@ do { \ > char __user *__ucu_dst = (_dst); \ > const char *__ucu_src = (_src); \ > size_t __ucu_len = (_len); \ > - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ > - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ > - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ > - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ > + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ > + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ > + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ > + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ > +} while (0) > + > +#define unsafe_get_loop(dst, src, len, type, label) \ > + while (len >= sizeof(type)) { \ > + unsafe_get_user(*(type __user *)(src),(type *)(dst),label); \ Hi, Just wanted to check if src and dst need to be swapped? Same for arm64 patch. > + dst += sizeof(type); \ > + src += sizeof(type); \ > + len -= sizeof(type); \ > + } > + > +#define unsafe_copy_from_user(_dst,_src,_len,label) \ > +do { \ > + char *__ucu_dst = (_dst); \ > + const char __user *__ucu_src = (_src); \ > + size_t __ucu_len = (_len); \ > + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ > + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ > + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ > + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ > } while (0) > > #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT > -- > 2.49.0 > >