| Message ID | 20191205000957.112719-7-thgarnie@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: PIE support to extend KASLR randomization | expand |
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 0340aad3f2fc..77fa291a60bb 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -742,11 +742,13 @@ 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. Position Independent Executable (PIE) support will allow to extend the KASLR randomization range below 0xffffffff80000000. Signed-off-by: Thomas Garnier <thgarnie@chromium.org> --- arch/x86/include/asm/processor.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)