arm64: Change .weak to SYM_FUNC_START_WEAK_PI for arch/arm64/lib/mem*.S

Commit 39d114ddc6 ("arm64: add KASAN support") added .weak directives to
arch/arm64/lib/mem*.S instead of changing the existing SYM_FUNC_START_PI
macros. 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.

Use the appropriate SYM_FUNC_START_WEAK_PI instead.

Fixes: 39d114ddc6 ("arm64: add KASAN support")
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201029181951.1866093-1-maskray@google.com
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Fangrui Song 2020-10-29 11:19:51 -07:00 committed by Will Deacon
parent ce3d31ad3c
commit ec9d78070d
3 changed files with 3 additions and 6 deletions

View File

@ -56,9 +56,8 @@
stp \reg1, \reg2, [\ptr], \val
.endm
.weak memcpy
SYM_FUNC_START_ALIAS(__memcpy)
SYM_FUNC_START_PI(memcpy)
SYM_FUNC_START_WEAK_PI(memcpy)
#include "copy_template.S"
ret
SYM_FUNC_END_PI(memcpy)

View File

@ -45,9 +45,8 @@ C_h .req x12
D_l .req x13
D_h .req x14
.weak memmove
SYM_FUNC_START_ALIAS(__memmove)
SYM_FUNC_START_PI(memmove)
SYM_FUNC_START_WEAK_PI(memmove)
cmp dstin, src
b.lo __memcpy
add tmp1, src, count

View File

@ -42,9 +42,8 @@ dst .req x8
tmp3w .req w9
tmp3 .req x9
.weak memset
SYM_FUNC_START_ALIAS(__memset)
SYM_FUNC_START_PI(memset)
SYM_FUNC_START_WEAK_PI(memset)
mov dst, dstin /* Preserve return value. */
and A_lw, val, #255
orr A_lw, A_lw, A_lw, lsl #8