| Message ID | 20200228000105.165012-7-thgarnie@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: PIE support to extend KASLR randomization | expand |
On Thu, Feb 27, 2020 at 04:00:51PM -0800, Thomas Garnier wrote: > Change the assembly code to use only relative references of symbols for the > kernel to be PIE compatible. > > Signed-off-by: Thomas Garnier <thgarnie@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > --- > arch/x86/include/asm/processor.h | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h > index 09705ccc393c..fdf6366c482d 100644 > --- a/arch/x86/include/asm/processor.h > +++ b/arch/x86/include/asm/processor.h > @@ -746,11 +746,13 @@ static inline void sync_core(void) > "pushfq\n\t" > "mov %%cs, %0\n\t" > "pushq %q0\n\t" > - "pushq $1f\n\t" > + "leaq 1f(%%rip), %q0\n\t" > + "pushq %q0\n\t" > "iretq\n\t" > UNWIND_HINT_RESTORE > "1:" > - : "=&r" (tmp), ASM_CALL_CONSTRAINT : : "cc", "memory"); > + : "=&r" (tmp), ASM_CALL_CONSTRAINT > + : : "cc", "memory"); > #endif > } > > -- > 2.25.1.481.gfbce0eb801-goog >
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 09705ccc393c..fdf6366c482d 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -746,11 +746,13 @@ static inline void sync_core(void) "pushfq\n\t" "mov %%cs, %0\n\t" "pushq %q0\n\t" - "pushq $1f\n\t" + "leaq 1f(%%rip), %q0\n\t" + "pushq %q0\n\t" "iretq\n\t" UNWIND_HINT_RESTORE "1:" - : "=&r" (tmp), ASM_CALL_CONSTRAINT : : "cc", "memory"); + : "=&r" (tmp), ASM_CALL_CONSTRAINT + : : "cc", "memory"); #endif }
Change the assembly code to use only relative references of symbols for the kernel to be PIE compatible. Signed-off-by: Thomas Garnier <thgarnie@chromium.org> --- arch/x86/include/asm/processor.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)