Change the assembly options to work with pointers instead of integers.
Position Independent Executable (PIE) support will allow to extend the
KASLR randomization range below 0xffffffff80000000.
Signed-off-by: Thomas Garnier <[email protected]>
---
arch/x86/include/asm/alternative.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index 094fbc9c0b1c..28a838106e5f 100644
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -243,7 +243,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
/* Like alternative_io, but for replacing a direct call with another one. */
#define alternative_call(oldfunc, newfunc, feature, output, input...) \
asm volatile (ALTERNATIVE("call %P[old]", "call %P[new]", feature) \
- : output : [old] "i" (oldfunc), [new] "i" (newfunc), ## input)
+ : output : [old] "X" (oldfunc), [new] "X" (newfunc), ## input)
/*
* Like alternative_call, but there are two features and respective functions.
@@ -256,8 +256,8 @@ static inline int alternatives_text_reserved(void *start, void *end)
asm volatile (ALTERNATIVE_2("call %P[old]", "call %P[new1]", feature1,\
"call %P[new2]", feature2) \
: output, ASM_CALL_CONSTRAINT \
- : [old] "i" (oldfunc), [new1] "i" (newfunc1), \
- [new2] "i" (newfunc2), ## input)
+ : [old] "X" (oldfunc), [new1] "X" (newfunc1), \
+ [new2] "X" (newfunc2), ## input)
/*
* use this macro(s) if you need more than one output parameter
--
2.22.0.770.g0f2c4a37fd-goog
On Tue, Jul 30, 2019 at 12:12:55PM -0700, Thomas Garnier wrote:
> Change the assembly options to work with pointers instead of integers.
This commit message is too vague. A before/after example would make it a
lot more clear why the change is needed.
Thx.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
On Mon, Aug 12, 2019 at 6:56 AM Borislav Petkov <[email protected]> wrote:
>
> On Tue, Jul 30, 2019 at 12:12:55PM -0700, Thomas Garnier wrote:
> > Change the assembly options to work with pointers instead of integers.
>
> This commit message is too vague. A before/after example would make it a
> lot more clear why the change is needed.
Sorry for the late reply, busy couple months.
I will try to do my best to explain it better in next iteration.
>
> Thx.
>
> --
> Regards/Gruss,
> Boris.
>
> Good mailing practices for 400: avoid top-posting and trim the reply.