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| author | H.J. Lu <hjl.tools@gmail.com> | 2018-07-14 05:59:29 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2018-07-14 05:59:53 -0700 |
| commit | faaee1f07ed25b2779bfd935ffb29f431b80d6d3 (patch) | |
| tree | 3c85f88e2312c67e0f0e54be10b0bec833c7541f /sysdeps/i386/bsd-_setjmp.S | |
| parent | ebff9c5cfae62e84dbd0456d564bd882818dc15f (diff) | |
| download | glibc-faaee1f07ed25b2779bfd935ffb29f431b80d6d3.tar.gz glibc-faaee1f07ed25b2779bfd935ffb29f431b80d6d3.tar.xz glibc-faaee1f07ed25b2779bfd935ffb29f431b80d6d3.zip | |
x86: Support shadow stack pointer in setjmp/longjmp
Save and restore shadow stack pointer in setjmp and longjmp to support shadow stack in Intel CET. Use feature_1 in tcbhead_t to check if shadow stack is enabled before saving and restoring shadow stack pointer. Reviewed-by: Carlos O'Donell <carlos@redhat.com> * sysdeps/i386/__longjmp.S: Include <jmp_buf-ssp.h>. (__longjmp): Restore shadow stack pointer if shadow stack is enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp isn't defined for __longjmp_cancel. * sysdeps/i386/bsd-_setjmp.S: Include <jmp_buf-ssp.h>. (_setjmp): Save shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined. * sysdeps/i386/bsd-setjmp.S: Include <jmp_buf-ssp.h>. (setjmp): Save shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined. * sysdeps/i386/setjmp.S: Include <jmp_buf-ssp.h>. (__sigsetjmp): Save shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined. * sysdeps/unix/sysv/linux/i386/____longjmp_chk.S: Include <jmp_buf-ssp.h>. (____longjmp_chk): Restore shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined. * sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers): Remove jmp_buf-ssp.sym. * sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S: Include <jmp_buf-ssp.h>. (____longjmp_chk): Restore shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined. * sysdeps/x86/Makefile (gen-as-const-headers): Add jmp_buf-ssp.sym. * sysdeps/x86/jmp_buf-ssp.sym: New dummy file. * sysdeps/x86_64/__longjmp.S: Include <jmp_buf-ssp.h>. (__longjmp): Restore shadow stack pointer if shadow stack is enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp isn't defined for __longjmp_cancel. * sysdeps/x86_64/setjmp.S: Include <jmp_buf-ssp.h>. (__sigsetjmp): Save shadow stack pointer if shadow stack is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
Diffstat (limited to 'sysdeps/i386/bsd-_setjmp.S')
| -rw-r--r-- | sysdeps/i386/bsd-_setjmp.S | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/sysdeps/i386/bsd-_setjmp.S b/sysdeps/i386/bsd-_setjmp.S index a626cc6d22..db47df0ba1 100644 --- a/sysdeps/i386/bsd-_setjmp.S +++ b/sysdeps/i386/bsd-_setjmp.S @@ -22,12 +22,18 @@ #include <sysdep.h> #include <jmpbuf-offsets.h> +#include <jmp_buf-ssp.h> #include <stap-probe.h> #define PARMS 4 /* no space for saved regs */ #define JMPBUF PARMS #define SIGMSK JMPBUF+4 +/* Don't save shadow stack register if shadow stack isn't enabled. */ +#if !SHSTK_ENABLED +# undef SHADOW_STACK_POINTER_OFFSET +#endif + ENTRY (_setjmp) xorl %eax, %eax @@ -51,6 +57,21 @@ ENTRY (_setjmp) movl %ebp, (JB_BP*4)(%edx) /* Save caller's frame pointer. */ movl %eax, JB_SIZE(%edx) /* No signal mask set. */ +#ifdef SHADOW_STACK_POINTER_OFFSET +# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET + /* Check if Shadow Stack is enabled. */ + testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET + jz L(skip_ssp) +# else + xorl %ecx, %ecx +# endif + /* Get the current Shadow-Stack-Pointer and save it. */ + rdsspd %ecx + movl %ecx, SHADOW_STACK_POINTER_OFFSET(%edx) +# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET +L(skip_ssp): +# endif +#endif ret END (_setjmp) libc_hidden_def (_setjmp) |