The following commit has been merged into the x86/urgent branch of tip: Commit-ID: 4d6ffa27b8e5116c0abb318790fd01d4e12d75e6 Gitweb: https://git.kernel.org/tip/4d6ffa27b8e5116c0abb318790fd01d4e12d75e6 Author: Fangrui Song <maskray@xxxxxxxxxx> AuthorDate: Mon, 02 Nov 2020 17:23:58 -08:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Wed, 04 Nov 2020 12:30:20 +01:00 x86/lib: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S Commit 393f203f5fd5 ("x86_64: kasan: add interceptors for memset/memmove/memcpy functions") added .weak directives to arch/x86/lib/mem*_64.S instead of changing the existing ENTRY macros to WEAK. This can lead to the assembly snippet .weak memcpy ... .globl memcpy which will produce a STB_WEAK memcpy with GNU as but STB_GLOBAL memcpy with LLVM's integrated assembler before LLVM 12. LLVM 12 (since https://reviews.llvm.org/D90108) will error on such an overridden symbol binding. Commit ef1e03152cb0 ("x86/asm: Make some functions local") changed ENTRY in arch/x86/lib/memcpy_64.S to SYM_FUNC_START_LOCAL, which was ineffective due to the preceding .weak directive. Use the appropriate SYM_FUNC_START_WEAK instead. Fixes: 393f203f5fd5 ("x86_64: kasan: add interceptors for memset/memmove/memcpy functions") Fixes: ef1e03152cb0 ("x86/asm: Make some functions local") Reported-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> Signed-off-by: Fangrui Song <maskray@xxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20201103012358.168682-1-maskray@xxxxxxxxxx --- arch/x86/lib/memcpy_64.S | 4 +--- arch/x86/lib/memmove_64.S | 4 +--- arch/x86/lib/memset_64.S | 4 +--- 3 files changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index 037faac..1e299ac 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -16,8 +16,6 @@ * to a jmp to memcpy_erms which does the REP; MOVSB mem copy. */ -.weak memcpy - /* * memcpy - Copy a memory block. * @@ -30,7 +28,7 @@ * rax original destination */ SYM_FUNC_START_ALIAS(__memcpy) -SYM_FUNC_START_LOCAL(memcpy) +SYM_FUNC_START_WEAK(memcpy) ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \ "jmp memcpy_erms", X86_FEATURE_ERMS diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 7ff00ea..41902fe 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -24,9 +24,7 @@ * Output: * rax: dest */ -.weak memmove - -SYM_FUNC_START_ALIAS(memmove) +SYM_FUNC_START_WEAK(memmove) SYM_FUNC_START(__memmove) mov %rdi, %rax diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S index 9ff15ee..0bfd26e 100644 --- a/arch/x86/lib/memset_64.S +++ b/arch/x86/lib/memset_64.S @@ -6,8 +6,6 @@ #include <asm/alternative-asm.h> #include <asm/export.h> -.weak memset - /* * ISO C memset - set a memory block to a byte value. This function uses fast * string to get better performance than the original function. The code is @@ -19,7 +17,7 @@ * * rax original destination */ -SYM_FUNC_START_ALIAS(memset) +SYM_FUNC_START_WEAK(memset) SYM_FUNC_START(__memset) /* * Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended
