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i386: Remove CET support

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CET is only support for x86_64, this patch reverts:

  - faaee1f07e x86: Support shadow stack pointer in setjmp/longjmp.
  - be9ccd27c0 i386: Add _CET_ENDBR to indirect jump targets in
    add_n.S/sub_n.S
  - c02695d776 x86/CET: Update vfork to prevent child return
  - 5d844e1b72 i386: Enable CET support in ucontext functions
  - 124bcde683 x86: Add _CET_ENDBR to functions in crti.S
  - 562837c002 x86: Add _CET_ENDBR to functions in dl-tlsdesc.S
  - f753fa7dea x86: Support IBT and SHSTK in Intel CET [BZ #21598]
  - 825b58f3fb i386-mcount.S: Add _CET_ENDBR to _mcount and __fentry__
  - 7e119cd582 i386: Use _CET_NOTRACK in i686/memcmp.S
  - 177824e232 i386: Use _CET_NOTRACK in memcmp-sse4.S
  - 0a899af097 i386: Use _CET_NOTRACK in memcpy-ssse3-rep.S
  - 7fb613361c i386: Use _CET_NOTRACK in memcpy-ssse3.S
  - 77a8ae0948 i386: Use _CET_NOTRACK in memset-sse2-rep.S
  - 00e7b76a8f i386: Use _CET_NOTRACK in memset-sse2.S
  - 90d15dc577 i386: Use _CET_NOTRACK in strcat-sse2.S
  - f1574581c7 i386: Use _CET_NOTRACK in strcpy-sse2.S
  - 4031d7484a i386/sub_n.S: Add a missing _CET_ENDBR to indirect jump
  - target
  -
Checked on i686-linux-gnu.
This commit is contained in:
Adhemerval Zanella 2024-01-05 10:36:40 -03:00
parent b7fc4a07f2
commit 25f1e16ef0
31 changed files with 75 additions and 770 deletions
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73
sysdeps/i386/__longjmp.S
View File

@ -19,55 +19,14 @@
#include <sysdep.h>
#include <pointer_guard.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
.text
ENTRY (__longjmp)
#ifdef PTR_DEMANGLE
movl 4(%esp), %eax /* User's jmp_buf in %eax. */
# 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 %edx, %edx
# endif
/* Check and adjust the Shadow-Stack-Pointer. */
rdsspd %edx
/* And compare it with the saved ssp value. */
subl SHADOW_STACK_POINTER_OFFSET(%eax), %edx
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. */
negl %edx
shrl $2, %edx
/* 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. */
addl $1, %edx
movl $255, %ebx
L(loop):
cmpl %ebx, %edx
cmovb %edx, %ebx
incsspd %ebx
subl %ebx, %edx
ja L(loop)
L(skip_ssp):
# endif
/* Save the return address now. */
movl (JB_PC*4)(%eax), %edx
/* Get the stack pointer. */
@ -98,38 +57,6 @@ L(skip_ssp):
#else
movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */
movl 8(%esp), %eax /* Second argument is return value. */
# ifdef SHADOW_STACK_POINTER_OFFSET
# if IS_IN (libc) && defined SHARED
/* Check if Shadow Stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
jz L(skip_ssp)
# endif
/* Check and adjust the Shadow-Stack-Pointer. */
xorl %edx, %edx
/* Get the current ssp. */
rdsspd %edx
/* And compare it with the saved ssp value. */
subl SHADOW_STACK_POINTER_OFFSET(%ecx), %edx
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. */
negl %edx
shrl $2, %edx
/* 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. */
addl $1, %edx
movl $255, %ebx
L(loop):
cmpl %ebx, %edx
cmovb %edx, %ebx
incsspd %ebx
subl %ebx, %edx
ja L(loop)
L(skip_ssp):
# endif
/* Save the return address now. */
movl (JB_PC*4)(%ecx), %edx
LIBC_PROBE (longjmp, 3, 4@%ecx, -4@%eax, 4@%edx)

25
sysdeps/i386/add_n.S
View File

@ -40,13 +40,6 @@ ENTRY (__mpn_add_n)
cfi_rel_offset (esi, 0)
movl S2(%esp),%edx
movl SIZE(%esp),%ecx
#if IBT_ENABLED
pushl %ebx
cfi_adjust_cfa_offset (4)
cfi_rel_offset (ebx, 0)
#endif
movl %ecx,%eax
shrl $3,%ecx /* compute count for unrolled loop */
negl %eax
@ -58,9 +51,6 @@ ENTRY (__mpn_add_n)
subl %eax,%esi /* ... by a constant when we ... */
subl %eax,%edx /* ... enter the loop */
shrl $2,%eax /* restore previous value */
#if IBT_ENABLED
leal -4(,%eax,4),%ebx /* Count for 4-byte endbr32 */
#endif
#ifdef PIC
/* Calculate start address in loop for PIC. Due to limitations in some
assemblers, Loop-L0-3 cannot be put into the leal */
@ -74,40 +64,30 @@ L(0): leal (%eax,%eax,8),%eax
#else
/* Calculate start address in loop for non-PIC. */
leal (L(oop) - 3)(%eax,%eax,8),%eax
#endif
#if IBT_ENABLED
addl %ebx,%eax /* Adjust for endbr32 */
#endif
jmp *%eax /* jump into loop */
ALIGN (3)
L(oop): movl (%esi),%eax
adcl (%edx),%eax
movl %eax,(%edi)
_CET_ENDBR
movl 4(%esi),%eax
adcl 4(%edx),%eax
movl %eax,4(%edi)
_CET_ENDBR
movl 8(%esi),%eax
adcl 8(%edx),%eax
movl %eax,8(%edi)
_CET_ENDBR
movl 12(%esi),%eax
adcl 12(%edx),%eax
movl %eax,12(%edi)
_CET_ENDBR
movl 16(%esi),%eax
adcl 16(%edx),%eax
movl %eax,16(%edi)
_CET_ENDBR
movl 20(%esi),%eax
adcl 20(%edx),%eax
movl %eax,20(%edi)
_CET_ENDBR
movl 24(%esi),%eax
adcl 24(%edx),%eax
movl %eax,24(%edi)
_CET_ENDBR
movl 28(%esi),%eax
adcl 28(%edx),%eax
movl %eax,28(%edi)
@ -120,11 +100,6 @@ L(oop): movl (%esi),%eax
sbbl %eax,%eax
negl %eax
#if IBT_ENABLED
popl %ebx
cfi_adjust_cfa_offset (-4)
cfi_restore (ebx)
#endif
popl %esi
cfi_adjust_cfa_offset (-4)
cfi_restore (esi)

21
sysdeps/i386/bsd-_setjmp.S
View File

@ -23,18 +23,12 @@
#include <sysdep.h>
#include <pointer_guard.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
@ -58,21 +52,6 @@ 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)

21
sysdeps/i386/bsd-setjmp.S
View File

@ -23,18 +23,12 @@
#include <sysdep.h>
#include <pointer_guard.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)
/* Note that we have to use a non-exported symbol in the next
jump since otherwise gas will emit it as a jump through the
@ -58,21 +52,6 @@ ENTRY (setjmp)
#endif
movl %ecx, (JB_PC*4)(%eax)
movl %ebp, (JB_BP*4)(%eax) /* Save caller's frame pointer. */
#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(%eax)
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
L(skip_ssp):
# endif
#endif
/* Call __sigjmp_save. */
pushl $1

2
sysdeps/i386/crti.S
View File

@ -61,7 +61,6 @@
.hidden _init
.type _init, @function
_init:
_CET_ENDBR
pushl %ebx
/* Maintain 16-byte stack alignment for called functions. */
subl $8, %esp
@ -82,7 +81,6 @@ _init:
.hidden _fini
.type _fini, @function
_fini:
_CET_ENDBR
pushl %ebx
subl $8, %esp
LOAD_PIC_REG (bx)

3
sysdeps/i386/dl-tlsdesc.S
View File

@ -37,7 +37,6 @@
cfi_startproc
.align 16
_dl_tlsdesc_return:
_CET_ENDBR
movl 4(%eax), %eax
ret
cfi_endproc
@ -59,7 +58,6 @@ _dl_tlsdesc_return:
cfi_startproc
.align 16
_dl_tlsdesc_undefweak:
_CET_ENDBR
movl 4(%eax), %eax
subl %gs:0, %eax
ret
@ -101,7 +99,6 @@ _dl_tlsdesc_dynamic (struct tlsdesc *tdp)
cfi_startproc
.align 16
_dl_tlsdesc_dynamic:
_CET_ENDBR
/* Like all TLS resolvers, preserve call-clobbered registers.
We need two scratch regs anyway. */
subl $28, %esp

4
sysdeps/i386/dl-trampoline.S
View File

@ -26,7 +26,6 @@
.align 16
_dl_runtime_resolve:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
@ -53,7 +52,6 @@ _dl_runtime_resolve:
.align 16
_dl_runtime_resolve_shstk:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %edx
@ -78,7 +76,6 @@ _dl_runtime_resolve_shstk:
.align 16
_dl_runtime_profile_shstk:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %esp
cfi_adjust_cfa_offset (4)
addl $8, (%esp) # Account for the pushed PLT data
@ -123,7 +120,6 @@ _dl_runtime_profile_shstk:
.align 16
_dl_runtime_profile:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %esp
cfi_adjust_cfa_offset (4)
addl $8, (%esp) # Account for the pushed PLT data

2
sysdeps/i386/i386-mcount.S
View File

@ -29,7 +29,6 @@
.type C_SYMBOL_NAME(_mcount), @function
.align ALIGNARG(4)
C_LABEL(_mcount)
_CET_ENDBR
/* Save the caller-clobbered registers. */
pushl %eax
pushl %ecx
@ -58,7 +57,6 @@ weak_alias (_mcount, mcount)
.type C_SYMBOL_NAME(__fentry__), @function
.align ALIGNARG(4)
C_LABEL(__fentry__)
_CET_ENDBR
/* Save the caller-clobbered registers. */
pushl %eax
pushl %ecx

25
sysdeps/i386/i686/add_n.S
View File

@ -44,13 +44,6 @@ ENTRY (__mpn_add_n)
cfi_rel_offset (esi, 0)
movl S2(%esp),%edx
movl SIZE(%esp),%ecx
#if IBT_ENABLED
pushl %ebx
cfi_adjust_cfa_offset (4)
cfi_rel_offset (ebx, 0)
#endif
movl %ecx,%eax
shrl $3,%ecx /* compute count for unrolled loop */
negl %eax
@ -62,9 +55,6 @@ ENTRY (__mpn_add_n)
subl %eax,%esi /* ... by a constant when we ... */
subl %eax,%edx /* ... enter the loop */
shrl $2,%eax /* restore previous value */
#if IBT_ENABLED
leal -4(,%eax,4),%ebx /* Count for 4-byte endbr32 */
#endif
#ifdef PIC
/* Calculate start address in loop for PIC. */
leal (L(oop)-L(0)-3)(%eax,%eax,8),%eax
@ -73,40 +63,30 @@ L(0):
#else
/* Calculate start address in loop for non-PIC. */
leal (L(oop) - 3)(%eax,%eax,8),%eax
#endif
#if IBT_ENABLED
addl %ebx,%eax /* Adjust for endbr32 */
#endif
jmp *%eax /* jump into loop */
ALIGN (3)
L(oop): movl (%esi),%eax
adcl (%edx),%eax
movl %eax,(%edi)
_CET_ENDBR
movl 4(%esi),%eax
adcl 4(%edx),%eax
movl %eax,4(%edi)
_CET_ENDBR
movl 8(%esi),%eax
adcl 8(%edx),%eax
movl %eax,8(%edi)
_CET_ENDBR
movl 12(%esi),%eax
adcl 12(%edx),%eax
movl %eax,12(%edi)
_CET_ENDBR
movl 16(%esi),%eax
adcl 16(%edx),%eax
movl %eax,16(%edi)
_CET_ENDBR
movl 20(%esi),%eax
adcl 20(%edx),%eax
movl %eax,20(%edi)
_CET_ENDBR
movl 24(%esi),%eax
adcl 24(%edx),%eax
movl %eax,24(%edi)
_CET_ENDBR
movl 28(%esi),%eax
adcl 28(%edx),%eax
movl %eax,28(%edi)
@ -119,11 +99,6 @@ L(oop): movl (%esi),%eax
sbbl %eax,%eax
negl %eax
#if IBT_ENABLED
popl %ebx
cfi_adjust_cfa_offset (-4)
cfi_restore (ebx)
#endif
popl %esi
cfi_adjust_cfa_offset (-4)
cfi_restore (esi)

4
sysdeps/i386/i686/memcmp.S
View File

@ -80,7 +80,7 @@ L(not_1):
LOAD_JUMP_TABLE_ENTRY (L(table_32bytes), %ecx)
addl %ecx, %edx
addl %ecx, %esi
_CET_NOTRACK jmp *%ebx
jmp *%ebx
ALIGN (4)
L(28bytes):
@ -326,7 +326,7 @@ L(32bytesormore):
LOAD_JUMP_TABLE_ENTRY (L(table_32bytes), %ecx)
addl %ecx, %edx
addl %ecx, %esi
_CET_NOTRACK jmp *%ebx
jmp *%ebx
L(load_ecx_28):
addl $0x4, %edx

4
sysdeps/i386/i686/multiarch/memcmp-sse4.S
View File

@ -58,7 +58,7 @@
absolute address. */ \
addl (%ebx,INDEX,SCALE), %ebx; \
/* We loaded the jump table and adjusted EDX/ESI. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
# else
# define JMPTBL(I, B) I
@ -66,7 +66,7 @@
jump table with relative offsets. INDEX is a register contains the
index into the jump table. SCALE is the scale of INDEX. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(,INDEX,SCALE)
jmp *TABLE(,INDEX,SCALE)
# endif

8
sysdeps/i386/i686/multiarch/memcpy-ssse3-rep.S
View File

@ -64,7 +64,7 @@
absolute address. */ \
addl (%ebx,INDEX,SCALE), %ebx; \
/* We loaded the jump table. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
# define BRANCH_TO_JMPTBL_ENTRY_VALUE(TABLE) \
addl $(TABLE - .), %ebx
@ -72,7 +72,7 @@
# define BRANCH_TO_JMPTBL_ENTRY_TAIL(TABLE, INDEX, SCALE) \
addl (%ebx,INDEX,SCALE), %ebx; \
/* We loaded the jump table. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
#else
# define PARMS 4
# define ENTRANCE
@ -84,12 +84,12 @@
absolute offsets. INDEX is a register contains the index into the
jump table. SCALE is the scale of INDEX. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(,INDEX,SCALE)
jmp *TABLE(,INDEX,SCALE)
# define BRANCH_TO_JMPTBL_ENTRY_VALUE(TABLE)
# define BRANCH_TO_JMPTBL_ENTRY_TAIL(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(,INDEX,SCALE)
jmp *TABLE(,INDEX,SCALE)
#endif
.section .text.ssse3,"ax",@progbits

4
sysdeps/i386/i686/multiarch/memcpy-ssse3.S
View File

@ -64,7 +64,7 @@
absolute address. */ \
addl (%ebx, INDEX, SCALE), %ebx; \
/* We loaded the jump table. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
# else
# define PARMS 4
@ -78,7 +78,7 @@
jump table. SCALE is the scale of INDEX. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(, INDEX, SCALE)
jmp *TABLE(, INDEX, SCALE)
# endif
.section .text.ssse3,"ax",@progbits

4
sysdeps/i386/i686/multiarch/memset-sse2-rep.S
View File

@ -56,7 +56,7 @@
add (%ebx,%ecx,4), %ebx; \
add %ecx, %edx; \
/* We loaded the jump table and adjusted EDX. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
#else
# define ENTRANCE
# define RETURN_END ret
@ -68,7 +68,7 @@
absolute offsets. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE) \
add %ecx, %edx; \
_CET_NOTRACK jmp *TABLE(,%ecx,4)
jmp *TABLE(,%ecx,4)
#endif
.section .text.sse2,"ax",@progbits

4
sysdeps/i386/i686/multiarch/memset-sse2.S
View File

@ -56,7 +56,7 @@
add (%ebx,%ecx,4), %ebx; \
add %ecx, %edx; \
/* We loaded the jump table and adjusted EDX. Go. */ \
_CET_NOTRACK jmp *%ebx
jmp *%ebx
#else
# define ENTRANCE
# define RETURN_END ret
@ -68,7 +68,7 @@
absolute offsets. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE) \
add %ecx, %edx; \
_CET_NOTRACK jmp *TABLE(,%ecx,4)
jmp *TABLE(,%ecx,4)
#endif
.section .text.sse2,"ax",@progbits

4
sysdeps/i386/i686/multiarch/strcat-sse2.S
View File

@ -49,7 +49,7 @@
absolute address. */ \
addl (%ecx,INDEX,SCALE), %ecx; \
/* We loaded the jump table and adjusted ECX. Go. */ \
_CET_NOTRACK jmp *%ecx
jmp *%ecx
# else
# define JMPTBL(I, B) I
@ -58,7 +58,7 @@
jump table. SCALE is the scale of INDEX. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(,INDEX,SCALE)
jmp *TABLE(,INDEX,SCALE)
# endif
# ifndef STRCAT

4
sysdeps/i386/i686/multiarch/strcpy-sse2.S
View File

@ -64,7 +64,7 @@
absolute address. */ \
addl (%ecx,INDEX,SCALE), %ecx; \
/* We loaded the jump table and adjusted ECX. Go. */ \
_CET_NOTRACK jmp *%ecx
jmp *%ecx
# else
# define JMPTBL(I, B) I
@ -73,7 +73,7 @@
jump table. SCALE is the scale of INDEX. */
# define BRANCH_TO_JMPTBL_ENTRY(TABLE, INDEX, SCALE) \
_CET_NOTRACK jmp *TABLE(,INDEX,SCALE)
jmp *TABLE(,INDEX,SCALE)
# endif
.text

21
sysdeps/i386/setjmp.S
View File

@ -19,7 +19,6 @@
#include <sysdep.h>
#include <pointer_guard.h>
#include <jmpbuf-offsets.h>
#include <jmp_buf-ssp.h>
#include <asm-syntax.h>
#include <stap-probe.h>
@ -27,11 +26,6 @@
#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 (__sigsetjmp)
movl JMPBUF(%esp), %eax
@ -53,21 +47,6 @@ ENTRY (__sigsetjmp)
movl %ecx, (JB_PC*4)(%eax)
movl %ebp, (JB_BP*4)(%eax) /* Save caller's frame pointer. */
#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(%eax)
# 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

1
sysdeps/i386/start.S
View File

@ -132,7 +132,6 @@ ENTRY (_start)
#if defined PIC && !defined SHARED
__wrap_main:
_CET_ENDBR
jmp main@PLT
#endif
END (_start)

25
sysdeps/i386/sub_n.S
View File

@ -40,13 +40,6 @@ ENTRY (__mpn_sub_n)
cfi_rel_offset (esi, 0)
movl S2(%esp),%edx
movl SIZE(%esp),%ecx
#if IBT_ENABLED
pushl %ebx
cfi_adjust_cfa_offset (4)
cfi_rel_offset (ebx, 0)
#endif
movl %ecx,%eax
shrl $3,%ecx /* compute count for unrolled loop */
negl %eax
@ -58,9 +51,6 @@ ENTRY (__mpn_sub_n)
subl %eax,%esi /* ... by a constant when we ... */
subl %eax,%edx /* ... enter the loop */
shrl $2,%eax /* restore previous value */
#if defined __CET__ && (__CET__ & 1) != 0
leal -4(,%eax,4),%ebx /* Count for 4-byte endbr32 */
#endif
#ifdef PIC
/* Calculate start address in loop for PIC. Due to limitations in some
assemblers, Loop-L0-3 cannot be put into the leal */
@ -74,40 +64,30 @@ L(0): leal (%eax,%eax,8),%eax
#else
/* Calculate start address in loop for non-PIC. */
leal (L(oop) - 3)(%eax,%eax,8),%eax
#endif
#if defined __CET__ && (__CET__ & 1) != 0
addl %ebx,%eax /* Adjust for endbr32 */
#endif
jmp *%eax /* jump into loop */
ALIGN (3)
L(oop): movl (%esi),%eax
sbbl (%edx),%eax
movl %eax,(%edi)
_CET_ENDBR
movl 4(%esi),%eax
sbbl 4(%edx),%eax
movl %eax,4(%edi)
_CET_ENDBR
movl 8(%esi),%eax
sbbl 8(%edx),%eax
movl %eax,8(%edi)
_CET_ENDBR
movl 12(%esi),%eax
sbbl 12(%edx),%eax
movl %eax,12(%edi)
_CET_ENDBR
movl 16(%esi),%eax
sbbl 16(%edx),%eax
movl %eax,16(%edi)
_CET_ENDBR
movl 20(%esi),%eax
sbbl 20(%edx),%eax
movl %eax,20(%edi)
_CET_ENDBR
movl 24(%esi),%eax
sbbl 24(%edx),%eax
movl %eax,24(%edi)
_CET_ENDBR
movl 28(%esi),%eax
sbbl 28(%edx),%eax
movl %eax,28(%edi)
@ -120,11 +100,6 @@ L(oop): movl (%esi),%eax
sbbl %eax,%eax
negl %eax
#if defined __CET__ && (__CET__ & 1) != 0
popl %ebx
cfi_adjust_cfa_offset (-4)
cfi_restore (ebx)
#endif
popl %esi
cfi_adjust_cfa_offset (-4)
cfi_restore (esi)

11
sysdeps/i386/sysdep.h
View File

@ -18,6 +18,8 @@
#include <sysdeps/x86/sysdep.h>
#define CET_ENABLED 0
/* It is desirable that the names of PIC thunks match those used by
GCC so that multiple copies are eliminated by the linker. Because
GCC 4.6 and earlier use __i686 in the names, it is necessary to
@ -37,6 +39,15 @@
/* Syntactic details of assembler. */
/* Define an entry point visible from C. */
#define ENTRY_P2ALIGN(name, alignment) \
.globl C_SYMBOL_NAME(name); \
.type C_SYMBOL_NAME(name),@function; \
.align ALIGNARG(alignment); \
C_LABEL(name) \
cfi_startproc; \
CALL_MCOUNT
/* If compiled for profiling, call `mcount' at the start of each function. */
#ifdef PROF
/* The mcount code relies on a normal frame pointer being on the stack

37
sysdeps/unix/sysv/linux/i386/____longjmp_chk.S
View File

@ -18,14 +18,9 @@
#include <sysdep.h>
#include <pointer_guard.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 shadow stack isn't enabled. */
#if !SHSTK_ENABLED
# undef SHADOW_STACK_POINTER_OFFSET
#endif
.section .rodata.str1.1,"aMS",@progbits,1
.type longjmp_msg,@object
@ -52,38 +47,6 @@ longjmp_msg:
ENTRY (____longjmp_chk)
movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */
#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 %edx, %edx
# endif
/* Check and adjust the Shadow-Stack-Pointer. */
rdsspd %edx
/* And compare it with the saved ssp value. */
subl SHADOW_STACK_POINTER_OFFSET(%ecx), %edx
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. */
negl %edx
shrl $2, %edx
/* 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. */
addl $1, %edx
movl $255, %ebx
L(loop):
cmpl %ebx, %edx
cmovb %edx, %ebx
incsspd %ebx
subl %ebx, %edx
ja L(loop)
L(skip_ssp):
#endif
/* Save the return address now. */
movl (JB_PC*4)(%ecx), %edx
/* Get the stack pointer. */

56
sysdeps/unix/sysv/linux/i386/getcontext.S
View File

@ -17,7 +17,6 @@
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <asm/prctl.h>
#include "ucontext_i.h"
@ -42,61 +41,6 @@ ENTRY(__getcontext)
movw %fs, %dx
movl %edx, oFS(%eax)
#if SHSTK_ENABLED
/* Check if shadow stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
jz L(no_shstk)
/* Save EAX in EDX. */
movl %eax, %edx
xorl %eax, %eax
cmpl %gs:SSP_BASE_OFFSET, %eax
jnz L(shadow_stack_bound_recorded)
/* Save EBX in the first scratch register slot. */
movl %ebx, oSCRATCH1(%edx)
/* Get the base address and size of the default shadow stack
which must be the current shadow stack since nothing has
been recorded yet. */
sub $24, %esp
mov %esp, %ecx
movl $ARCH_CET_STATUS, %ebx
movl $__NR_arch_prctl, %eax
ENTER_KERNEL
testl %eax, %eax
jz L(continue_no_err)
/* This should never happen. */
hlt
L(continue_no_err):
/* Restore EBX from the first scratch register slot. */
movl oSCRATCH1(%edx), %ebx
/* Record the base of the current shadow stack. */
movl 8(%esp), %eax
movl %eax, %gs:SSP_BASE_OFFSET
add $24, %esp
L(shadow_stack_bound_recorded):
/* Load address of the context data structure. */
movl 4(%esp), %eax
/* Get the current shadow stack pointer. */
rdsspd %edx
/* NB: Save the caller's shadow stack so that we can jump back
to the caller directly. */
addl $4, %edx
movl %edx, oSSP(%eax)
/* Save the current shadow stack base in ucontext. */
movl %gs:SSP_BASE_OFFSET, %edx
movl %edx, (oSSP + 4)(%eax)
L(no_shstk):
#endif
/* We have separate floating-point register content memory on the
stack. We use the __fpregs_mem block in the context. Set the
links up correctly. */

123
sysdeps/unix/sysv/linux/i386/makecontext.S
View File

@ -17,7 +17,6 @@
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <asm/prctl.h>
#include "ucontext_i.h"
@ -68,127 +67,6 @@ ENTRY(__makecontext)
jnz 1b
2:
#if SHSTK_ENABLED
/* Check if Shadow Stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
jz L(skip_ssp)
/* Reload the pointer to ucontext. */
movl 4(%esp), %eax
/* Shadow stack is enabled. We need to allocate a new shadow
stack. */
subl oSS_SP(%eax), %edx
shrl $STACK_SIZE_TO_SHADOW_STACK_SIZE_SHIFT, %edx
/* Align shadow stack size to 8 bytes. */
addl $7, %edx
andl $-8, %edx
/* Store shadow stack size in __ssp[2]. */
movl %edx, (oSSP + 8)(%eax)
/* Save ESI in the second scratch register slot. */
movl %esi, oSCRATCH2(%eax)
/* Save EDI in the third scratch register slot. */
movl %edi, oSCRATCH3(%eax)
/* Save the pointer to ucontext. */
movl %eax, %edi
/* Get the original shadow stack pointer. */
rdsspd %esi
/* Align the saved original shadow stack pointer to the next
8 byte aligned boundary. */
andl $-8, %esi
/* Load the top of the new stack into EDX. */
movl oESP(%eax), %edx
/* We need to terminate the FDE here because the unwinder looks
at ra-1 for unwind information. */
cfi_endproc
/* Swap the original stack pointer with the top of the new
stack. */
xchgl %esp, %edx
/* Add 4 bytes since CALL will push the 4-byte return address
onto stack. */
addl $4, %esp
/* Allocate the new shadow stack. Save EBX in the first scratch
register slot. */
movl %ebx, oSCRATCH1(%eax)
/* CET syscall takes 64-bit sizes. */
subl $16, %esp
movl (oSSP + 8)(%eax), %ecx
movl %ecx, (%esp)
movl $0, 4(%esp)
movl %ecx, 8(%esp)
movl $0, 12(%esp)
movl %esp, %ecx
movl $ARCH_CET_ALLOC_SHSTK, %ebx
movl $__NR_arch_prctl, %eax
ENTER_KERNEL
testl %eax, %eax
jne L(hlt) /* This should never happen. */
/* Copy the base address of the new shadow stack to __ssp[1]. */
movl (%esp), %eax
movl %eax, (oSSP + 4)(%edi)
addl $16, %esp
/* Restore EBX from the first scratch register slot. */
movl oSCRATCH1(%edi), %ebx
/* Get the size of the new shadow stack. */
movl (oSSP + 8)(%edi), %ecx
/* Use the restore stoken to restore the new shadow stack. */
rstorssp -8(%eax, %ecx)
/* Save the restore token at the next 8 byte aligned boundary
on the original shadow stack. */
saveprevssp
/* Push the address of "jmp exitcode" onto the new stack as
well as the new shadow stack. */
call 1f
jmp L(exitcode)
1:
/* Get the new shadow stack pointer. */
rdsspd %eax
/* Use the restore stoken to restore the original shadow stack. */
rstorssp -8(%esi)
/* Save the restore token on the new shadow stack. */
saveprevssp
/* Store the new shadow stack pointer in __ssp[0]. */
movl %eax, oSSP(%edi)
/* Restore the original stack. */
mov %edx, %esp
cfi_startproc
/* Restore ESI from the second scratch register slot. */
movl oSCRATCH2(%edi), %esi
/* Restore EDI from the third scratch register slot. */
movl oSCRATCH3(%edi), %edi
ret
L(skip_ssp):
#endif
/* If the function we call returns we must continue with the
context which is given in the uc_link element. To do this
set the return address for the function the user provides
@ -244,7 +122,6 @@ L(call_exit):
call HIDDEN_JUMPTARGET(exit)
/* The 'exit' call should never return. In case it does cause
the process to terminate. */
L(hlt):
hlt
cfi_startproc
END(__makecontext)

101
sysdeps/unix/sysv/linux/i386/setcontext.S
View File

@ -17,7 +17,6 @@
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <asm/prctl.h>
#include "ucontext_i.h"
@ -56,6 +55,9 @@ ENTRY(__setcontext)
movl oFS(%eax), %ecx
movw %cx, %fs
/* Fetch the address to return to. */
movl oEIP(%eax), %ecx
/* Load the new stack pointer. */
cfi_def_cfa (eax, 0)
cfi_offset (edi, oEDI)
@ -64,103 +66,6 @@ ENTRY(__setcontext)
cfi_offset (ebx, oEBX)
movl oESP(%eax), %esp
#if SHSTK_ENABLED
/* Check if Shadow Stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
jz L(no_shstk)
/* If the base of the target shadow stack is the same as the
base of the current shadow stack, we unwind the shadow
stack. Otherwise it is a stack switch and we look for a
restore token. */
movl oSSP(%eax), %esi
movl %esi, %edi
/* Get the base of the target shadow stack. */
movl (oSSP + 4)(%eax), %ecx
cmpl %gs:SSP_BASE_OFFSET, %ecx
je L(unwind_shadow_stack)
/* Align the saved original shadow stack pointer to the next
8 byte aligned boundary. */
andl $-8, %esi
L(find_restore_token_loop):
/* Look for a restore token. */
movl -8(%esi), %ebx
andl $-8, %ebx
cmpl %esi, %ebx
je L(restore_shadow_stack)
/* Try the next slot. */
subl $8, %esi
jmp L(find_restore_token_loop)
L(restore_shadow_stack):
/* Pop return address from the shadow stack since setcontext
will not return. */
movl $1, %ebx
incsspd %ebx
/* Use the restore stoken to restore the target shadow stack. */
rstorssp -8(%esi)
/* Save the restore token on the old shadow stack. NB: This
restore token may be checked by setcontext or swapcontext
later. */
saveprevssp
/* Record the new shadow stack base that was switched to. */
movl (oSSP + 4)(%eax), %ebx
movl %ebx, %gs:SSP_BASE_OFFSET
L(unwind_shadow_stack):
rdsspd %ebx
subl %edi, %ebx
je L(skip_unwind_shadow_stack)
negl %ebx
shrl $2, %ebx
movl $255, %esi
L(loop):
cmpl %esi, %ebx
cmovb %ebx, %esi
incsspd %esi
subl %esi, %ebx
ja L(loop)
L(skip_unwind_shadow_stack):
/* Load the values of all the preserved registers (except ESP). */
movl oEDI(%eax), %edi
movl oESI(%eax), %esi
movl oEBP(%eax), %ebp
movl oEBX(%eax), %ebx
/* Get the return address set with getcontext. */
movl oEIP(%eax), %ecx
/* Check if return address is valid for the case when setcontext
is invoked from L(exitcode) with linked context. */
rdsspd %eax
cmpl (%eax), %ecx
/* Clear EAX to indicate success. NB: Don't use xorl to keep
EFLAGS for jne. */
movl $0, %eax
jne L(jmp)
/* Return to the new context if return address valid. */
pushl %ecx
ret
L(jmp):
/* Jump to the new context directly. */
jmp *%ecx
L(no_shstk):
#endif
/* Fetch the address to return to. */
movl oEIP(%eax), %ecx
/* Push the return address on the new stack so we can return there. */
pushl %ecx

139
sysdeps/unix/sysv/linux/i386/swapcontext.S
View File

@ -17,7 +17,6 @@
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <asm/prctl.h>
#include "ucontext_i.h"
@ -76,144 +75,6 @@ ENTRY(__swapcontext)
movl oFS(%eax), %edx
movw %dx, %fs
#if SHSTK_ENABLED
/* Check if Shadow Stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %gs:FEATURE_1_OFFSET
jz L(no_shstk)
xorl %eax, %eax
cmpl %gs:SSP_BASE_OFFSET, %eax
jnz L(shadow_stack_bound_recorded)
/* Get the base address and size of the default shadow stack
which must be the current shadow stack since nothing has
been recorded yet. */
sub $24, %esp
mov %esp, %ecx
movl $ARCH_CET_STATUS, %ebx
movl $__NR_arch_prctl, %eax
ENTER_KERNEL
testl %eax, %eax
jz L(continue_no_err)
/* This should never happen. */
hlt
L(continue_no_err):
/* Record the base of the current shadow stack. */
movl 8(%esp), %eax
movl %eax, %gs:SSP_BASE_OFFSET
add $24, %esp
L(shadow_stack_bound_recorded):
/* Load address of the context data structure we save in. */
movl 4(%esp), %eax
/* Load address of the context data structure we swap in */
movl 8(%esp), %edx
/* If we unwind the stack, we can't undo stack unwinding. Just
save the target shadow stack pointer as the current shadow
stack pointer. */
movl oSSP(%edx), %ecx
movl %ecx, oSSP(%eax)
/* Save the current shadow stack base in ucontext. */
movl %gs:SSP_BASE_OFFSET, %ecx
movl %ecx, (oSSP + 4)(%eax)
/* If the base of the target shadow stack is the same as the
base of the current shadow stack, we unwind the shadow
stack. Otherwise it is a stack switch and we look for a
restore token. */
movl oSSP(%edx), %esi
movl %esi, %edi
/* Get the base of the target shadow stack. */
movl (oSSP + 4)(%edx), %ecx
cmpl %gs:SSP_BASE_OFFSET, %ecx
je L(unwind_shadow_stack)
/* Align the saved original shadow stack pointer to the next
8 byte aligned boundary. */
andl $-8, %esi
L(find_restore_token_loop):
/* Look for a restore token. */
movl -8(%esi), %ebx
andl $-8, %ebx
cmpl %esi, %ebx
je L(restore_shadow_stack)
/* Try the next slot. */
subl $8, %esi
jmp L(find_restore_token_loop)
L(restore_shadow_stack):
/* The target shadow stack will be restored. Save the current
shadow stack pointer. */
rdsspd %ecx
movl %ecx, oSSP(%eax)
/* Use the restore stoken to restore the target shadow stack. */
rstorssp -8(%esi)
/* Save the restore token on the old shadow stack. NB: This
restore token may be checked by setcontext or swapcontext
later. */
saveprevssp
/* Record the new shadow stack base that was switched to. */
movl (oSSP + 4)(%edx), %ebx
movl %ebx, %gs:SSP_BASE_OFFSET
L(unwind_shadow_stack):
rdsspd %ebx
subl %edi, %ebx
je L(skip_unwind_shadow_stack)
negl %ebx
shrl $2, %ebx
movl $255, %esi
L(loop):
cmpl %esi, %ebx
cmovb %ebx, %esi
incsspd %esi
subl %esi, %ebx
ja L(loop)
L(skip_unwind_shadow_stack):
/* Load the new stack pointer. */
movl oESP(%edx), %esp
/* Load the values of all the preserved registers (except ESP). */
movl oEDI(%edx), %edi
movl oESI(%edx), %esi
movl oEBP(%edx), %ebp
movl oEBX(%edx), %ebx
/* Get the return address set with getcontext. */
movl oEIP(%edx), %ecx
/* Check if return address is valid for the case when setcontext
is invoked from L(exitcode) with linked context. */
rdsspd %eax
cmpl (%eax), %ecx
/* Clear EAX to indicate success. NB: Don't use xorl to keep
EFLAGS for jne. */
movl $0, %eax
jne L(jmp)
/* Return to the new context if return address valid. */
pushl %ecx
ret
L(jmp):
/* Jump to the new context directly. */
jmp *%ecx
L(no_shstk):
#endif
/* Fetch the address to return to. */
movl oEIP(%eax), %ecx

5
sysdeps/unix/sysv/linux/i386/sysdep.h
View File

@ -446,9 +446,4 @@ struct libc_do_syscall_args
#endif /* __ASSEMBLER__ */
/* Each shadow stack slot takes 4 bytes. Assuming that each stack
frame takes 128 bytes, this is used to compute shadow stack size
from stack size. */
#define STACK_SIZE_TO_SHADOW_STACK_SIZE_SHIFT 5
#endif /* linux/i386/sysdep.h */

4
sysdeps/unix/sysv/linux/i386/ucontext_i.sym
View File

@ -22,10 +22,6 @@ oEBP mreg (EBP)
oESP mreg (ESP)
oEBX mreg (EBX)
oEIP mreg (EIP)
oSCRATCH1 mreg (EAX)
oSCRATCH2 mreg (ECX)
oSCRATCH3 mreg (EDX)
oFPREGS mcontext (fpregs)
oSIGMASK ucontext (uc_sigmask)
oFPREGSMEM ucontext (__fpregs_mem)
oSSP ucontext (__ssp)

24
sysdeps/unix/sysv/linux/i386/vfork.S
View File

@ -20,6 +20,7 @@
#include <bits/errno.h>
#include <tcb-offsets.h>
/* Clone the calling process, but without copying the whole address space.
The calling process is suspended until the new process exits or is
replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
@ -46,29 +47,6 @@ ENTRY (__vfork)
/* Branch forward if it failed. */
jae SYSCALL_ERROR_LABEL
#if SHSTK_ENABLED
/* Check if shadow stack is in use. */
xorl %edx, %edx
rdsspd %edx
testl %edx, %edx
/* Normal return if shadow stack isn't in use. */
je L(no_shstk)
testl %eax, %eax
/* In parent, normal return. */
jnz L(no_shstk)
/* NB: In child, jump back to caller via indirect branch without
popping shadow stack which is shared with parent. Keep shadow
stack mismatched so that child returns in the vfork-calling
function will trigger SIGSEGV. */
popl %ecx
cfi_adjust_cfa_offset (-4)
jmp *%ecx
L(no_shstk):
#endif
ret
PSEUDO_END (__vfork)

44
sysdeps/x86/sysdep.h
View File

@ -21,33 +21,6 @@
#include <sysdeps/generic/sysdep.h>
/* __CET__ is defined by GCC with Control-Flow Protection values:
enum cf_protection_level
{
CF_NONE = 0,
CF_BRANCH = 1 << 0,
CF_RETURN = 1 << 1,
CF_FULL = CF_BRANCH | CF_RETURN,
CF_SET = 1 << 2
};
*/
/* Set if CF_BRANCH (IBT) is enabled. */
#define X86_FEATURE_1_IBT (1U << 0)
/* Set if CF_RETURN (SHSTK) is enabled. */
#define X86_FEATURE_1_SHSTK (1U << 1)
#ifdef __CET__
# define CET_ENABLED 1
# define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT)
# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK)
#else
# define CET_ENABLED 0
# define IBT_ENABLED 0
# define SHSTK_ENABLED 0
#endif
/* Offset for fxsave/xsave area used by _dl_runtime_resolve. Also need
space to preserve RCX, RDX, RSI, RDI, R8, R9 and RAX. It must be
aligned to 16 bytes for fxsave and 64 bytes for xsave. */
@ -66,27 +39,10 @@ enum cf_protection_level
/* Syntactic details of assembler. */
#ifdef _CET_ENDBR
# define _CET_NOTRACK notrack
#else
# define _CET_ENDBR
# define _CET_NOTRACK
#endif
/* ELF uses byte-counts for .align, most others use log2 of count of bytes. */
#define ALIGNARG(log2) 1<<log2
#define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
/* Define an entry point visible from C. */
#define ENTRY_P2ALIGN(name, alignment) \
.globl C_SYMBOL_NAME(name); \
.type C_SYMBOL_NAME(name),@function; \
.align ALIGNARG(alignment); \
C_LABEL(name) \
cfi_startproc; \
_CET_ENDBR; \
CALL_MCOUNT
/* Common entry 16 byte aligns. */
#define ENTRY(name) ENTRY_P2ALIGN (name, 4)

42
sysdeps/x86_64/sysdep.h
View File

@ -22,10 +22,52 @@
#include <sysdeps/x86/sysdep.h>
#include <x86-lp_size.h>
/* __CET__ is defined by GCC with Control-Flow Protection values:
enum cf_protection_level
{
CF_NONE = 0,
CF_BRANCH = 1 << 0,
CF_RETURN = 1 << 1,
CF_FULL = CF_BRANCH | CF_RETURN,
CF_SET = 1 << 2
};
*/
/* Set if CF_BRANCH (IBT) is enabled. */
#define X86_FEATURE_1_IBT (1U << 0)
/* Set if CF_RETURN (SHSTK) is enabled. */
#define X86_FEATURE_1_SHSTK (1U << 1)
#ifdef __CET__
# define CET_ENABLED 1
# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK)
#else
# define CET_ENABLED 0
# define SHSTK_ENABLED 0
#endif
#ifdef __ASSEMBLER__
/* Syntactic details of assembler. */
#ifdef _CET_ENDBR
# define _CET_NOTRACK notrack
#else
# define _CET_ENDBR
# define _CET_NOTRACK
#endif
/* Define an entry point visible from C. */
#define ENTRY_P2ALIGN(name, alignment) \
.globl C_SYMBOL_NAME(name); \
.type C_SYMBOL_NAME(name),@function; \
.align ALIGNARG(alignment); \
C_LABEL(name) \
cfi_startproc; \
_CET_ENDBR; \
CALL_MCOUNT
/* This macro is for setting proper CFI with DW_CFA_expression describing
the register as saved relative to %rsp instead of relative to the CFA.
Expression is DW_OP_drop, DW_OP_breg7 (%rsp is register 7), sleb128 offset