On Wed, 6 May 2026 16:09:16 +0200 Jens Remus <[email protected]> wrote:
> On 5/5/2026 2:17 PM, Jens Remus wrote: > > From: Josh Poimboeuf <[email protected]> > > > > Add an x86 implementation of unsafe_copy_from_user() similar to the > > existing unsafe_copy_to_user(). > > > diff --git a/arch/x86/include/asm/uaccess.h > > b/arch/x86/include/asm/uaccess.h > > > -#define unsafe_copy_to_user(_dst,_src,_len,label) \ > > -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); \ > > +#define unsafe_copy_to_user(_dst, _src, _len, label) > > \ > > +do { > > \ > > + void __user *__dst = (_dst); > > \ > > + const void *__src = (_src); > > \ > > + size_t __len = (_len); > > \ > > + unsafe_copy_to_user_loop(__dst, __src, __len, u64, label); > > \ > > + unsafe_copy_to_user_loop(__dst, __src, __len, u32, label); > > \ > > + unsafe_copy_to_user_loop(__dst, __src, __len, u16, label); > > \ > > + unsafe_copy_to_user_loop(__dst, __src, __len, u8, label); > > \ > > +} while (0) > > + > > +#define unsafe_copy_from_user_loop(dst, src, len, type, label) > > \ > > + while (len >= sizeof(type)) { > > \ > > + unsafe_get_user(*(type *)(dst), (type __user *)(src), label); > > \ > > + dst += sizeof(type); > > \ > > + src += sizeof(type); > > \ > > + len -= sizeof(type); > > \ > > + } > > + > > +#define unsafe_copy_from_user(_dst, _src, _len, label) > > \ > > +do { > > \ > > + void *__dst = (_dst); > > \ > > + void __user *__src = (_src); > > \ > > const void __user *__src = (_src); > \ > > This was suggested by Sashiko AI review. Any objections? Try compiling it :-) -- David > > > + size_t __len = (_len); > > \ > > + unsafe_copy_from_user_loop(__dst, __src, __len, u64, label); > > \ > > + unsafe_copy_from_user_loop(__dst, __src, __len, u32, label); > > \ > > + unsafe_copy_from_user_loop(__dst, __src, __len, u16, label); > > \ > > + unsafe_copy_from_user_loop(__dst, __src, __len, u8, label); > > \ > > } while (0) > > > > #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT > > Thanks and regards, > Jens
