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| author | Peter Zijlstra <peterz@infradead.org> | 2023-01-12 22:43:58 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-01-13 13:48:17 +0300 |
| commit | 69d4c0d3218692ffa56b0e1b9c76c50c699d7044 (patch) | |
| tree | 632f322958ef60af5237ba029b2b82e5b4595c5d /arch/x86/lib | |
| parent | 365bd03ff63fb7433a49c453472cf54830b677bf (diff) | |
| download | linux-69d4c0d3218692ffa56b0e1b9c76c50c699d7044.tar.xz | |
entry, kasan, x86: Disallow overriding mem*() functions
KASAN cannot just hijack the mem*() functions, it needs to emit
__asan_mem*() variants if it wants instrumentation (other sanitizers
already do this).
vmlinux.o: warning: objtool: sync_regs+0x24: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: vc_switch_off_ist+0xbe: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: fixup_bad_iret+0x36: call to memset() leaves .noinstr.text section
vmlinux.o: warning: objtool: __sev_get_ghcb+0xa0: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: __sev_put_ghcb+0x35: call to memcpy() leaves .noinstr.text section
Remove the weak aliases to ensure nobody hijacks these functions and
add them to the noinstr section.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195542.028523143@infradead.org
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/memcpy_64.S | 5 | ||||
| -rw-r--r-- | arch/x86/lib/memmove_64.S | 4 | ||||
| -rw-r--r-- | arch/x86/lib/memset_64.S | 4 |
3 files changed, 8 insertions, 5 deletions
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index dd8cd8831251..a64017602010 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -8,7 +8,7 @@ #include <asm/alternative.h> #include <asm/export.h> -.pushsection .noinstr.text, "ax" +.section .noinstr.text, "ax" /* * We build a jump to memcpy_orig by default which gets NOPped out on @@ -43,7 +43,7 @@ SYM_TYPED_FUNC_START(__memcpy) SYM_FUNC_END(__memcpy) EXPORT_SYMBOL(__memcpy) -SYM_FUNC_ALIAS_WEAK(memcpy, __memcpy) +SYM_FUNC_ALIAS(memcpy, __memcpy) EXPORT_SYMBOL(memcpy) /* @@ -184,4 +184,3 @@ SYM_FUNC_START_LOCAL(memcpy_orig) RET SYM_FUNC_END(memcpy_orig) -.popsection diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 724bbf83eb5b..02661861e5dd 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -13,6 +13,8 @@ #undef memmove +.section .noinstr.text, "ax" + /* * Implement memmove(). This can handle overlap between src and dst. * @@ -213,5 +215,5 @@ SYM_FUNC_START(__memmove) SYM_FUNC_END(__memmove) EXPORT_SYMBOL(__memmove) -SYM_FUNC_ALIAS_WEAK(memmove, __memmove) +SYM_FUNC_ALIAS(memmove, __memmove) EXPORT_SYMBOL(memmove) diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S index fc9ffd3ff3b2..6143b1a6fa2c 100644 --- a/arch/x86/lib/memset_64.S +++ b/arch/x86/lib/memset_64.S @@ -6,6 +6,8 @@ #include <asm/alternative.h> #include <asm/export.h> +.section .noinstr.text, "ax" + /* * 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 @@ -43,7 +45,7 @@ SYM_FUNC_START(__memset) SYM_FUNC_END(__memset) EXPORT_SYMBOL(__memset) -SYM_FUNC_ALIAS_WEAK(memset, __memset) +SYM_FUNC_ALIAS(memset, __memset) EXPORT_SYMBOL(memset) /* |