2015-09-17 23:15 GMT+03:00 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>: > On Thu, 17 Sep 2015 23:02:14 +0300 Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> wrote: > >> 2015-09-17 22:37 GMT+03:00 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>: >> > On Thu, 17 Sep 2015 09:17:56 +0800 kbuild test robot <fengguang.wu@xxxxxxxxx> wrote: >> > >> >> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master >> >> head: 72714841b705a5b9bccf37ee85a62352bee3a3ef >> >> commit: 393f203f5fd54421fddb1e2a263f64d3876eeadb x86_64: kasan: add interceptors for memset/memmove/memcpy functions >> >> date: 7 months ago >> >> config: i386-randconfig-i0-201537 (attached as .config) >> >> reproduce: >> >> git checkout 393f203f5fd54421fddb1e2a263f64d3876eeadb >> >> # save the attached .config to linux build tree >> >> make ARCH=i386 >> >> >> >> All warnings (new ones prefixed by >>): >> >> >> >> drivers/firmware/efi/libstub/efi-stub-helper.c: In function 'efi_relocate_kernel': >> >> >> drivers/firmware/efi/libstub/efi-stub-helper.c:599:2: warning: implicit declaration of function 'memcpy' [-Wimplicit-function-declaration] >> >> memcpy((void *)new_addr, (void *)cur_image_addr, image_size); >> > >> > I can't reproduce this. >> > >> > But whatever. I'll do this: >> > >> > --- a/drivers/firmware/efi/libstub/efi-stub-helper.c~drivers-firmware-efi-libstub-efi-stub-helperc-needs-stringh >> > +++ a/drivers/firmware/efi/libstub/efi-stub-helper.c >> > @@ -11,6 +11,7 @@ >> > */ >> > >> > #include <linux/efi.h> >> > +#include <linux/string.h> >> >> This won't help. >> arch/x86/include/asm/string_32.h has several variants of #define memcpy() >> But it doesn't have declaration of memcpy function like: >> void memcpy(const void *to, const void *from, size_t len); >> Thus '#undef memcpy' causes this warning, and including >> <linux/string.h> won't help (It probably already included) > > Well, I can't tell either way because that warning doesn't come out for > me with the provided config. > That's strange, but I could reproduce this and warning didn't go away after adding include. >> Patch from KASAN for arm64 series: >> http://marc.info/?l=linux-mm&m=144248270719929&w=2 ([PATCH v6 3/6] >> x86, efi, kasan: #undef memset/memcpy/memmove per arch.) >> should fix this warning, as it moves '#undef memcpy' under #ifdef >> X86_64 in arch/x86/include/asm/efi.h > > hm, that patch was misfiled. We want this for for 4.3-rc. I'll queue > it up. Good. > I hope it's independent of the rest of that patch series? > Yes, this patch doesn't depend on the rest of patches, although the rest of patches depends on it. > > From: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> > Subject: x86, efi, kasan: #undef memset/memcpy/memmove per arch > > In not-instrumented code KASAN replaces instrumented memset/memcpy/memmove > with not-instrumented analogues __memset/__memcpy/__memove. > > However, on x86 the EFI stub is not linked with the kernel. It uses > not-instrumented mem*() functions from arch/x86/boot/compressed/string.c > > So we don't replace them with __mem*() variants in EFI stub. > > On ARM64 the EFI stub is linked with the kernel, so we should replace > mem*() functions with __mem*(), because the EFI stub runs before KASAN > sets up early shadow. > > So let's move these #undef mem* into arch's asm/efi.h which is also > included by the EFI stub. > > Also, this will fix the warning in 32-bit build reported by kbuild test > robot: > > efi-stub-helper.c:599:2: warning: implicit declaration of function 'memcpy' > > Signed-off-by: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> > Reported-by: Fengguang Wu <fengguang.wu@xxxxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Matt Fleming <matt.fleming@xxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxxxxx> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > arch/x86/include/asm/efi.h | 12 ++++++++++++ > drivers/firmware/efi/libstub/efistub.h | 4 ---- > 2 files changed, 12 insertions(+), 4 deletions(-) > > diff -puN arch/x86/include/asm/efi.h~x86-efi-kasan-undef-memset-memcpy-memmove-per-arch arch/x86/include/asm/efi.h > --- a/arch/x86/include/asm/efi.h~x86-efi-kasan-undef-memset-memcpy-memmove-per-arch > +++ a/arch/x86/include/asm/efi.h > @@ -86,6 +86,18 @@ extern u64 asmlinkage efi_call(void *fp, > extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size, > u32 type, u64 attribute); > > +/* > + * CONFIG_KASAN may redefine memset to __memset. > + * __memset function is present only in kernel binary. > + * Since the EFI stub linked into a separate binary it > + * doesn't have __memset(). So we should use standard > + * memset from arch/x86/boot/compressed/string.c > + * The same applies to memcpy and memmove. > + */ > +#undef memcpy > +#undef memset > +#undef memmove > + > #endif /* CONFIG_X86_32 */ > > extern struct efi_scratch efi_scratch; > diff -puN drivers/firmware/efi/libstub/efistub.h~x86-efi-kasan-undef-memset-memcpy-memmove-per-arch drivers/firmware/efi/libstub/efistub.h > --- a/drivers/firmware/efi/libstub/efistub.h~x86-efi-kasan-undef-memset-memcpy-memmove-per-arch > +++ a/drivers/firmware/efi/libstub/efistub.h > @@ -5,10 +5,6 @@ > /* error code which can't be mistaken for valid address */ > #define EFI_ERROR (~0UL) > > -#undef memcpy > -#undef memset > -#undef memmove > - > void efi_char16_printk(efi_system_table_t *, efi_char16_t *); > > efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image, > _ > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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