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authorH.J. Lu <hjl.tools@gmail.com>2018-07-17 16:11:13 -0700
committerH.J. Lu <hjl.tools@gmail.com>2018-07-17 16:11:44 -0700
commitbe9ccd27c09ee76c5397125bfa0fefae318a2996 (patch)
treefedd9f2980ad4b1d2afd66a83032dc317d253bd3
parent5efc6777ad57c2055b618e0b8b8dc1e5bc4ab29a (diff)
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i386: Add _CET_ENDBR to indirect jump targets in add_n.S/sub_n.S
i386 add_n.S and sub_n.S use a trick to implment jump tables with LEA. We can't use conditional branches nor normal jump tables since jump table entries use EFLAGS set by jump table index. This patch adds _CET_ENDBR to indirect jump targets and adjust destination for _CET_ENDBR. Reviewed-by: Carlos O'Donell <carlos@redhat.com> * sysdeps/i386/add_n.S: Include <sysdep.h>, instead of "sysdep.h". (__mpn_add_n): Save and restore %ebx if IBT is enabed. Add _CET_ENDBR to indirect jump targets and adjust jump destination for _CET_ENDBR. * sysdeps/i386/i686/add_n.S: Include <sysdep.h>, instead of "sysdep.h". (__mpn_add_n): Save and restore %ebx if IBT is enabed. Add _CET_ENDBR to indirect jump targets and adjust jump destination for _CET_ENDBR. * sysdeps/i386/sub_n.S: Include <sysdep.h>, instead of "sysdep.h". (__mpn_sub_n): Save and restore %ebx if IBT is enabed. Add _CET_ENDBR to indirect jump targets and adjust jump destination for _CET_ENDBR.
-rw-r--r--ChangeLog18
-rw-r--r--sysdeps/i386/add_n.S27
-rw-r--r--sysdeps/i386/i686/add_n.S27
-rw-r--r--sysdeps/i386/sub_n.S26
4 files changed, 95 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog
index e2d560a46d..f8ef428fa6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,23 @@
2018-07-17 H.J. Lu <hongjiu.lu@intel.com>
+ * sysdeps/i386/add_n.S: Include <sysdep.h>, instead of
+ "sysdep.h".
+ (__mpn_add_n): Save and restore %ebx if IBT is enabed. Add
+ _CET_ENDBR to indirect jump targets and adjust jump destination
+ for _CET_ENDBR.
+ * sysdeps/i386/i686/add_n.S: Include <sysdep.h>, instead of
+ "sysdep.h".
+ (__mpn_add_n): Save and restore %ebx if IBT is enabed. Add
+ _CET_ENDBR to indirect jump targets and adjust jump destination
+ for _CET_ENDBR.
+ * sysdeps/i386/sub_n.S: Include <sysdep.h>, instead of
+ "sysdep.h".
+ (__mpn_sub_n): Save and restore %ebx if IBT is enabed. Add
+ _CET_ENDBR to indirect jump targets and adjust jump destination
+ for _CET_ENDBR.
+
+2018-07-17 H.J. Lu <hongjiu.lu@intel.com>
+
* sysdeps/x86_64/multiarch/strcmp-sse42.S (STRCMP_SSE42): Add
_CET_ENDBR.
diff --git a/sysdeps/i386/add_n.S b/sysdeps/i386/add_n.S
index d6a35237b0..998858469c 100644
--- a/sysdeps/i386/add_n.S
+++ b/sysdeps/i386/add_n.S
@@ -17,7 +17,7 @@
along with the GNU MP Library; see the file COPYING.LIB. If not,
see <http://www.gnu.org/licenses/>. */
-#include "sysdep.h"
+#include <sysdep.h>
#include "asm-syntax.h"
#define PARMS 4+8 /* space for 2 saved regs */
@@ -40,6 +40,13 @@ 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
@@ -51,6 +58,9 @@ 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 */
@@ -65,29 +75,39 @@ L(0): leal (%eax,%eax,8),%eax
/* 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)
@@ -100,6 +120,11 @@ 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)
diff --git a/sysdeps/i386/i686/add_n.S b/sysdeps/i386/i686/add_n.S
index 5c6c1448d6..0c95919d30 100644
--- a/sysdeps/i386/i686/add_n.S
+++ b/sysdeps/i386/i686/add_n.S
@@ -17,7 +17,7 @@
along with the GNU MP Library; see the file COPYING.LIB. If not,
see <http://www.gnu.org/licenses/>. */
-#include "sysdep.h"
+#include <sysdep.h>
#include "asm-syntax.h"
#define PARMS 4+8 /* space for 2 saved regs */
@@ -44,6 +44,13 @@ 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
@@ -55,6 +62,9 @@ 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
@@ -64,29 +74,39 @@ L(0):
/* 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)
@@ -99,6 +119,11 @@ 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)
diff --git a/sysdeps/i386/sub_n.S b/sysdeps/i386/sub_n.S
index 7c6f48c32e..ada0cf5ec9 100644
--- a/sysdeps/i386/sub_n.S
+++ b/sysdeps/i386/sub_n.S
@@ -17,7 +17,7 @@
along with the GNU MP Library; see the file COPYING.LIB. If not,
see <http://www.gnu.org/licenses/>. */
-#include "sysdep.h"
+#include <sysdep.h>
#include "asm-syntax.h"
#define PARMS 4+8 /* space for 2 saved regs */
@@ -40,6 +40,13 @@ 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
@@ -51,6 +58,9 @@ 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 */
@@ -65,29 +75,38 @@ L(0): leal (%eax,%eax,8),%eax
/* 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)
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)
@@ -100,6 +119,11 @@ 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)