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.
This commit is contained in:
H.J. Lu
parent
ebff9c5cfa
commit
faaee1f07e
37
ChangeLog
37
ChangeLog
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@ -1,3 +1,40 @@
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2018-07-14 Igor Tsimbalist <igor.v.tsimbalist@intel.com>
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H.J. Lu <hongjiu.lu@intel.com>
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* sysdeps/i386/__longjmp.S: Include <jmp_buf-ssp.h>.
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(__longjmp): Restore shadow stack pointer if shadow stack is
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enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
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isn't defined for __longjmp_cancel.
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* sysdeps/i386/bsd-_setjmp.S: Include <jmp_buf-ssp.h>.
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(_setjmp): Save shadow stack pointer if shadow stack is enabled
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and SHADOW_STACK_POINTER_OFFSET is defined.
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* sysdeps/i386/bsd-setjmp.S: Include <jmp_buf-ssp.h>.
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(setjmp): Save shadow stack pointer if shadow stack is enabled
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and SHADOW_STACK_POINTER_OFFSET is defined.
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* sysdeps/i386/setjmp.S: Include <jmp_buf-ssp.h>.
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(__sigsetjmp): Save shadow stack pointer if shadow stack is
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enabled and SHADOW_STACK_POINTER_OFFSET is defined.
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* sysdeps/unix/sysv/linux/i386/____longjmp_chk.S: Include
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<jmp_buf-ssp.h>.
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(____longjmp_chk): Restore shadow stack pointer if shadow stack
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is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
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* sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers):
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Remove jmp_buf-ssp.sym.
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* sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S: Include
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<jmp_buf-ssp.h>.
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(____longjmp_chk): Restore shadow stack pointer if shadow stack
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is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
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* sysdeps/x86/Makefile (gen-as-const-headers): Add
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jmp_buf-ssp.sym.
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* sysdeps/x86/jmp_buf-ssp.sym: New dummy file.
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* sysdeps/x86_64/__longjmp.S: Include <jmp_buf-ssp.h>.
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(__longjmp): Restore shadow stack pointer if shadow stack is
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enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
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isn't defined for __longjmp_cancel.
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* sysdeps/x86_64/setjmp.S: Include <jmp_buf-ssp.h>.
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(__sigsetjmp): Save shadow stack pointer if shadow stack is
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enabled and SHADOW_STACK_POINTER_OFFSET is defined.
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2018-07-14 H.J. Lu <hongjiu.lu@intel.com>
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[BZ #22563]
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@ -18,14 +18,55 @@
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#include <sysdep.h>
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#include <jmpbuf-offsets.h>
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#include <jmp_buf-ssp.h>
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#include <asm-syntax.h>
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#include <stap-probe.h>
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/* Don't restore shadow stack register if
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1. Shadow stack isn't enabled. Or
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2. __longjmp is defined for __longjmp_cancel.
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*/
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#if !SHSTK_ENABLED || defined __longjmp
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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.text
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ENTRY (__longjmp)
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#ifdef PTR_DEMANGLE
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movl 4(%esp), %eax /* User's jmp_buf in %eax. */
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# ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %edx, %edx
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# endif
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/* Check and adjust the Shadow-Stack-Pointer. */
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rdsspd %edx
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/* And compare it with the saved ssp value. */
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subl SHADOW_STACK_POINTER_OFFSET(%eax), %edx
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je L(skip_ssp)
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/* Count the number of frames to adjust and adjust it
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with incssp instruction. The instruction can adjust
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the ssp by [0..255] value only thus use a loop if
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the number of frames is bigger than 255. */
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negl %edx
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shrl $2, %edx
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/* NB: We saved Shadow-Stack-Pointer of setjmp. Since we are
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restoring Shadow-Stack-Pointer of setjmp's caller, we
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need to unwind shadow stack by one more frame. */
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addl $1, %edx
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movl $255, %ebx
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L(loop):
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cmpl %ebx, %edx
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cmovb %edx, %ebx
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incsspd %ebx
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subl %ebx, %edx
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ja L(loop)
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L(skip_ssp):
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# endif
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/* Save the return address now. */
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movl (JB_PC*4)(%eax), %edx
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/* Get the stack pointer. */
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@ -56,6 +97,38 @@ ENTRY (__longjmp)
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#else
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movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */
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movl 8(%esp), %eax /* Second argument is return value. */
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# ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# endif
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/* Check and adjust the Shadow-Stack-Pointer. */
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xorl %edx, %edx
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/* Get the current ssp. */
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rdsspd %edx
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/* And compare it with the saved ssp value. */
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subl SHADOW_STACK_POINTER_OFFSET(%ecx), %edx
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je L(skip_ssp)
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/* Count the number of frames to adjust and adjust it
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with incssp instruction. The instruction can adjust
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the ssp by [0..255] value only thus use a loop if
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the number of frames is bigger than 255. */
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negl %edx
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shrl $2, %edx
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/* NB: We saved Shadow-Stack-Pointer of setjmp. Since we are
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restoring Shadow-Stack-Pointer of setjmp's caller, we
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need to unwind shadow stack by one more frame. */
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addl $1, %edx
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movl $255, %ebx
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L(loop):
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cmpl %ebx, %edx
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cmovb %edx, %ebx
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incsspd %ebx
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subl %ebx, %edx
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ja L(loop)
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L(skip_ssp):
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# endif
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/* Save the return address now. */
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movl (JB_PC*4)(%ecx), %edx
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LIBC_PROBE (longjmp, 3, 4@%ecx, -4@%eax, 4@%edx)
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@ -22,12 +22,18 @@
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#include <sysdep.h>
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#include <jmpbuf-offsets.h>
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#include <jmp_buf-ssp.h>
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#include <stap-probe.h>
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#define PARMS 4 /* no space for saved regs */
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#define JMPBUF PARMS
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#define SIGMSK JMPBUF+4
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/* Don't save shadow stack register if shadow stack isn't enabled. */
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#if !SHSTK_ENABLED
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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ENTRY (_setjmp)
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xorl %eax, %eax
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@ -51,6 +57,21 @@ ENTRY (_setjmp)
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movl %ebp, (JB_BP*4)(%edx) /* Save caller's frame pointer. */
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movl %eax, JB_SIZE(%edx) /* No signal mask set. */
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#ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %ecx, %ecx
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# endif
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/* Get the current Shadow-Stack-Pointer and save it. */
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rdsspd %ecx
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movl %ecx, SHADOW_STACK_POINTER_OFFSET(%edx)
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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L(skip_ssp):
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# endif
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#endif
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ret
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END (_setjmp)
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libc_hidden_def (_setjmp)
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@ -22,12 +22,18 @@
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#include <sysdep.h>
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#include <jmpbuf-offsets.h>
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#include <jmp_buf-ssp.h>
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#include <stap-probe.h>
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#define PARMS 4 /* no space for saved regs */
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#define JMPBUF PARMS
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#define SIGMSK JMPBUF+4
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/* Don't save shadow stack register if shadow stack isn't enabled. */
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#if !SHSTK_ENABLED
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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ENTRY (setjmp)
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/* Note that we have to use a non-exported symbol in the next
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jump since otherwise gas will emit it as a jump through the
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@ -51,6 +57,21 @@ ENTRY (setjmp)
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#endif
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movl %ecx, (JB_PC*4)(%eax)
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movl %ebp, (JB_BP*4)(%eax) /* Save caller's frame pointer. */
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#ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %ecx, %ecx
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# endif
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/* Get the current Shadow-Stack-Pointer and save it. */
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rdsspd %ecx
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movl %ecx, SHADOW_STACK_POINTER_OFFSET(%eax)
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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L(skip_ssp):
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# endif
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#endif
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/* Call __sigjmp_save. */
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pushl $1
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#include <sysdep.h>
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#include <jmpbuf-offsets.h>
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#include <jmp_buf-ssp.h>
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#include <asm-syntax.h>
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#include <stap-probe.h>
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#define JMPBUF PARMS
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#define SIGMSK JMPBUF+4
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/* Don't save shadow stack register if shadow stack isn't enabled. */
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#if !SHSTK_ENABLED
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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ENTRY (__sigsetjmp)
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movl JMPBUF(%esp), %eax
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movl %ecx, (JB_PC*4)(%eax)
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movl %ebp, (JB_BP*4)(%eax) /* Save caller's frame pointer. */
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#ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %ecx, %ecx
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# endif
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/* Get the current Shadow-Stack-Pointer and save it. */
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rdsspd %ecx
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movl %ecx, SHADOW_STACK_POINTER_OFFSET(%eax)
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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L(skip_ssp):
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# endif
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#endif
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#if IS_IN (rtld)
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/* In ld.so we never save the signal mask. */
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xorl %eax, %eax
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#include <sysdep.h>
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#include <jmpbuf-offsets.h>
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#include <jmp_buf-ssp.h>
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#include <asm-syntax.h>
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#include <stap-probe.h>
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/* Don't restore shadow stack register if shadow stack isn't enabled. */
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#if !SHSTK_ENABLED
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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.section .rodata.str1.1,"aMS",@progbits,1
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.type longjmp_msg,@object
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@ -46,6 +51,38 @@ longjmp_msg:
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ENTRY (____longjmp_chk)
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movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */
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#ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %edx, %edx
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# endif
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/* Check and adjust the Shadow-Stack-Pointer. */
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rdsspd %edx
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/* And compare it with the saved ssp value. */
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subl SHADOW_STACK_POINTER_OFFSET(%ecx), %edx
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je L(skip_ssp)
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/* Count the number of frames to adjust and adjust it
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with incssp instruction. The instruction can adjust
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the ssp by [0..255] value only thus use a loop if
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the number of frames is bigger than 255. */
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negl %edx
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shrl $2, %edx
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/* NB: We saved Shadow-Stack-Pointer of setjmp. Since we are
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restoring Shadow-Stack-Pointer of setjmp's caller, we
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need to unwind shadow stack by one more frame. */
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addl $1, %edx
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movl $255, %ebx
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L(loop):
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cmpl %ebx, %edx
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cmovb %edx, %ebx
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incsspd %ebx
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subl %ebx, %edx
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ja L(loop)
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L(skip_ssp):
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#endif
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/* Save the return address now. */
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movl (JB_PC*4)(%ecx), %edx
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/* Get the stack pointer. */
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endif
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ifeq ($(subdir),setjmp)
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gen-as-const-headers += jmp_buf-ssp.sym
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tests += tst-saved_mask-1
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endif
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#include <asm-syntax.h>
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#include <stap-probe.h>
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/* Don't restore shadow stack register if shadow stack isn't enabled. */
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#if !SHSTK_ENABLED
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# undef SHADOW_STACK_POINTER_OFFSET
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#endif
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#include <sigaltstack-offsets.h>
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#include <jmp_buf-ssp.h>
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.section .rodata.str1.1,"aMS",@progbits,1
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.type longjmp_msg,@object
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cfi_restore (%rsi)
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.Lok:
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#ifdef SHADOW_STACK_POINTER_OFFSET
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# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
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/* Check if Shadow Stack is enabled. */
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testl $X86_FEATURE_1_SHSTK, %fs:FEATURE_1_OFFSET
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jz L(skip_ssp)
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# else
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xorl %eax, %eax
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# endif
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/* Check and adjust the Shadow-Stack-Pointer. */
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rdsspq %rax
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/* And compare it with the saved ssp value. */
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subq SHADOW_STACK_POINTER_OFFSET(%rdi), %rax
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je L(skip_ssp)
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/* Count the number of frames to adjust and adjust it
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with incssp instruction. The instruction can adjust
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the ssp by [0..255] value only thus use a loop if
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the number of frames is bigger than 255. */
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negq %rax
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shrq $3, %rax
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/* NB: We saved Shadow-Stack-Pointer of setjmp. Since we are
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restoring Shadow-Stack-Pointer of setjmp's caller, we
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need to unwind shadow stack by one more frame. */
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addq $1, %rax
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movl $255, %ebx
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L(loop):
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cmpq %rbx, %rax
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cmovb %rax, %rbx
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incsspq %rbx
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subq %rbx, %rax
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ja L(loop)
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L(skip_ssp):
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#endif
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LIBC_PROBE (longjmp, 3, LP_SIZE@%RDI_LP, -4@%esi, LP_SIZE@%RDX_LP)
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/* We add unwind information for the target here. */
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cfi_def_cfa(%rdi, 0)
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@ -10,5 +10,6 @@ tests-static += tst-get-cpu-features-static
|
|||
endif
|
||||
|
||||
ifeq ($(subdir),setjmp)
|
||||
gen-as-const-headers += jmp_buf-ssp.sym
|
||||
sysdep_routines += __longjmp_cancel
|
||||
endif
|
||||
|
|
|
|||
|
|
@ -0,0 +1 @@
|
|||
-- FIXME: Define SHADOW_STACK_POINTER_OFFSET to support shadow stack.
|
||||
|
|
@ -17,9 +17,18 @@
|
|||
|
||||
#include <sysdep.h>
|
||||
#include <jmpbuf-offsets.h>
|
||||
#include <jmp_buf-ssp.h>
|
||||
#include <asm-syntax.h>
|
||||
#include <stap-probe.h>
|
||||
|
||||
/* Don't restore shadow stack register if
|
||||
1. Shadow stack isn't enabled. Or
|
||||
2. __longjmp is defined for __longjmp_cancel.
|
||||
*/
|
||||
#if !SHSTK_ENABLED || defined __longjmp
|
||||
# undef SHADOW_STACK_POINTER_OFFSET
|
||||
#endif
|
||||
|
||||
/* Jump to the position specified by ENV, causing the
|
||||
setjmp call there to return VAL, or 1 if VAL is 0.
|
||||
void __longjmp (__jmp_buf env, int val). */
|
||||
|
|
@ -41,6 +50,41 @@ ENTRY(__longjmp)
|
|||
shlq $32, %rax
|
||||
orq %rax, %r9
|
||||
# endif
|
||||
#endif
|
||||
#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, %fs:FEATURE_1_OFFSET
|
||||
jz L(skip_ssp)
|
||||
# else
|
||||
xorl %eax, %eax
|
||||
# endif
|
||||
/* Check and adjust the Shadow-Stack-Pointer. */
|
||||
/* Get the current ssp. */
|
||||
rdsspq %rax
|
||||
/* And compare it with the saved ssp value. */
|
||||
subq SHADOW_STACK_POINTER_OFFSET(%rdi), %rax
|
||||
je L(skip_ssp)
|
||||
/* Count the number of frames to adjust and adjust it
|
||||
with incssp instruction. The instruction can adjust
|
||||
the ssp by [0..255] value only thus use a loop if
|
||||
the number of frames is bigger than 255. */
|
||||
negq %rax
|
||||
shrq $3, %rax
|
||||
/* NB: We saved Shadow-Stack-Pointer of setjmp. Since we are
|
||||
restoring Shadow-Stack-Pointer of setjmp's caller, we
|
||||
need to unwind shadow stack by one more frame. */
|
||||
addq $1, %rax
|
||||
|
||||
movl $255, %ebx
|
||||
L(loop):
|
||||
cmpq %rbx, %rax
|
||||
cmovb %rax, %rbx
|
||||
incsspq %rbx
|
||||
subq %rbx, %rax
|
||||
ja L(loop)
|
||||
|
||||
L(skip_ssp):
|
||||
#endif
|
||||
LIBC_PROBE (longjmp, 3, LP_SIZE@%RDI_LP, -4@%esi, LP_SIZE@%RDX_LP)
|
||||
/* We add unwind information for the target here. */
|
||||
|
|
|
|||
|
|
@ -18,9 +18,15 @@
|
|||
|
||||
#include <sysdep.h>
|
||||
#include <jmpbuf-offsets.h>
|
||||
#include <jmp_buf-ssp.h>
|
||||
#include <asm-syntax.h>
|
||||
#include <stap-probe.h>
|
||||
|
||||
/* Don't save shadow stack register if shadow stack isn't enabled. */
|
||||
#if !SHSTK_ENABLED
|
||||
# undef SHADOW_STACK_POINTER_OFFSET
|
||||
#endif
|
||||
|
||||
ENTRY (__sigsetjmp)
|
||||
/* Save registers. */
|
||||
movq %rbx, (JB_RBX*8)(%rdi)
|
||||
|
|
@ -54,6 +60,21 @@ ENTRY (__sigsetjmp)
|
|||
#endif
|
||||
movq %rax, (JB_PC*8)(%rdi)
|
||||
|
||||
#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, %fs:FEATURE_1_OFFSET
|
||||
jz L(skip_ssp)
|
||||
# else
|
||||
xorl %eax, %eax
|
||||
# endif
|
||||
/* Get the current Shadow-Stack-Pointer and save it. */
|
||||
rdsspq %rax
|
||||
movq %rax, SHADOW_STACK_POINTER_OFFSET(%rdi)
|
||||
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
|
||||
L(skip_ssp):
|
||||
# endif
|
||||
#endif
|
||||
#if IS_IN (rtld)
|
||||
/* In ld.so we never save the signal mask. */
|
||||
xorl %eax, %eax
|
||||
|
|
|
|||
Loading…
Reference in New Issue