am 91624eae: am 57866a6d: Merge changes Iea8d03de,I2014f959

* commit '91624eae9aa90e123ae37843d94861120d2433a4':
  Implement setjmp cookies on x86_64.
  Implement setjmp cookies on x86.

libc/arch-x86/bionic/setjmp.S

@@ -41,30 +41,49 @@
 #define _JB_SIGMASK 6
 #define _JB_SIGFLAG 7
 
+.macro m_mangle_registers reg
+  xorl \reg,%edx
+  xorl \reg,%ebx
+  xorl \reg,%esp
+  xorl \reg,%ebp
+  xorl \reg,%esi
+  xorl \reg,%edi
+.endm
+
+.macro m_unmangle_registers reg
+  m_mangle_registers \reg
+.endm
+
 ENTRY(setjmp)
   movl 4(%esp),%ecx
-  movl $1,(_JB_SIGFLAG * 4)(%ecx)
+  mov $1,%eax
-  jmp .L_sigsetjmp_signal_mask
+  jmp .L_sigsetjmp
 END(setjmp)
 
 ENTRY(_setjmp)
   movl 4(%esp),%ecx
-  movl $0,(_JB_SIGFLAG * 4)(%ecx)
+  movl $0,%eax
-  jmp .L_sigsetjmp_no_signal_mask
+  jmp .L_sigsetjmp
 END(_setjmp)
 
 ENTRY(sigsetjmp)
   movl 4(%esp),%ecx
   movl 8(%esp),%eax
 
-  // Record whether or not the signal mask is valid.
+.L_sigsetjmp:
+  PIC_PROLOGUE
+  pushl %eax
+  call PIC_PLT(__bionic_setjmp_cookie_get)
+  addl $4,%esp
+  PIC_EPILOGUE
+
+  // Record the setjmp cookie and whether or not we're saving the signal mask.
   movl %eax,(_JB_SIGFLAG * 4)(%ecx)
 
   // Do we need to save the signal mask?
-  testl %eax,%eax
+  testl $1,%eax
   jz 1f
 
-.L_sigsetjmp_signal_mask:
   // Get the current signal mask.
   PIC_PROLOGUE
   pushl $0
@@ -76,16 +95,21 @@ ENTRY(sigsetjmp)
   movl 4(%esp),%ecx
   movl %eax,(_JB_SIGMASK * 4)(%ecx)
 
-.L_sigsetjmp_no_signal_mask:
 1:
+  // Fetch the setjmp cookie and clear the signal flag bit.
+  movl (_JB_SIGFLAG * 4)(%ecx),%eax
+  andl $-2,%eax
+
   // Save the callee-save registers.
   movl 0(%esp),%edx
+  m_mangle_registers %eax
   movl %edx,(_JB_EDX * 4)(%ecx)
   movl %ebx,(_JB_EBX * 4)(%ecx)
   movl %esp,(_JB_ESP * 4)(%ecx)
   movl %ebp,(_JB_EBP * 4)(%ecx)
   movl %esi,(_JB_ESI * 4)(%ecx)
   movl %edi,(_JB_EDI * 4)(%ecx)
+  m_unmangle_registers %eax
 
   xorl %eax,%eax
   ret
@@ -94,7 +118,8 @@ END(sigsetjmp)
 ENTRY(siglongjmp)
   // Do we have a signal mask to restore?
   movl 4(%esp),%edx
-  cmpl $0,(_JB_SIGFLAG * 4)(%edx)
+  movl (_JB_SIGFLAG * 4)(%edx), %eax
+  testl $1,%eax
   jz 1f
 
   // Restore the signal mask.
@@ -108,12 +133,29 @@ ENTRY(siglongjmp)
   // Restore the callee-save registers.
   movl 4(%esp),%edx
   movl 8(%esp),%eax
-  movl (_JB_EDX * 4)(%edx),%ecx
+
-  movl (_JB_EBX * 4)(%edx),%ebx
+  movl (_JB_SIGFLAG * 4)(%edx),%ecx
-  movl (_JB_ESP * 4)(%edx),%esp
+  andl $-2,%ecx
-  movl (_JB_EBP * 4)(%edx),%ebp
+
-  movl (_JB_ESI * 4)(%edx),%esi
+  movl %ecx,%ebx
-  movl (_JB_EDI * 4)(%edx),%edi
+  movl %ecx,%esp
+  movl %ecx,%ebp
+  movl %ecx,%esi
+  movl %ecx,%edi
+  xorl (_JB_EDX * 4)(%edx),%ecx
+  xorl (_JB_EBX * 4)(%edx),%ebx
+  xorl (_JB_ESP * 4)(%edx),%esp
+  xorl (_JB_EBP * 4)(%edx),%ebp
+  xorl (_JB_ESI * 4)(%edx),%esi
+  xorl (_JB_EDI * 4)(%edx),%edi
+
+  PIC_PROLOGUE
+  pushl %eax
+  pushl (_JB_SIGFLAG * 4)(%edx)
+  call PIC_PLT(__bionic_setjmp_cookie_check)
+  addl $4,%esp
+  popl %eax
+  PIC_EPILOGUE
 
   testl %eax,%eax
   jnz 2f

libc/arch-x86_64/bionic/setjmp.S

@@ -50,6 +50,25 @@
 #define _JB_SIGMASK 9
 #define _JB_SIGMASK_RT 10 // sigprocmask will write here too.
 
+#define MANGLE_REGISTERS 1
+.macro m_mangle_registers reg
+#if MANGLE_REGISTERS
+  xorq \reg,%rbx
+  xorq \reg,%rbp
+  xorq \reg,%r12
+  xorq \reg,%r13
+  xorq \reg,%r14
+  xorq \reg,%r15
+  xorq \reg,%rsp
+  xorq \reg,%r11
+#endif
+.endm
+
+.macro m_unmangle_registers reg
+  m_mangle_registers \reg
+.endm
+
+
 ENTRY(setjmp)
   movl $1,%esi
   jmp PIC_PLT(sigsetjmp)
@@ -62,11 +81,17 @@ END(_setjmp)
 
 // int sigsetjmp(sigjmp_buf env, int save_signal_mask);
 ENTRY(sigsetjmp)
-  // Record whether or not we're saving the signal mask.
+  pushq %rdi
-  movl %esi,(_JB_SIGFLAG * 8)(%rdi)
+  movq %rsi,%rdi
+  call PIC_PLT(__bionic_setjmp_cookie_get)
+  popq %rdi
+
+  // Record setjmp cookie and whether or not we're saving the signal mask.
+  movq %rax,(_JB_SIGFLAG * 8)(%rdi)
+  pushq %rax
 
   // Do we need to save the signal mask?
-  testl %esi,%esi
+  testq $1,%rax
   jz 2f
 
   // Save current signal mask.
@@ -79,7 +104,10 @@ ENTRY(sigsetjmp)
 
 2:
   // Save the callee-save registers.
+  popq %rax
+  andq $-2,%rax
   movq (%rsp),%r11
+  m_mangle_registers %rax
   movq %rbx,(_JB_RBX * 8)(%rdi)
   movq %rbp,(_JB_RBP * 8)(%rdi)
   movq %r12,(_JB_R12 * 8)(%rdi)
@@ -88,6 +116,7 @@ ENTRY(sigsetjmp)
   movq %r15,(_JB_R15 * 8)(%rdi)
   movq %rsp,(_JB_RSP * 8)(%rdi)
   movq %r11,(_JB_PC  * 8)(%rdi)
+  m_unmangle_registers %rax
 
   xorl %eax,%eax
   ret
@@ -99,7 +128,9 @@ ENTRY(siglongjmp)
   pushq %rsi // Push 'value'.
 
   // Do we need to restore the signal mask?
-  cmpl $0,(_JB_SIGFLAG * 8)(%rdi)
+  movq (_JB_SIGFLAG * 8)(%rdi), %rdi
+  pushq %rdi // Push cookie
+  testq $1, %rdi
   jz 2f
 
   // Restore the signal mask.
@@ -109,6 +140,10 @@ ENTRY(siglongjmp)
   call PIC_PLT(sigprocmask)
 
 2:
+  // Fetch the setjmp cookie and clear the signal flag bit.
+  popq %rcx
+  andq $-2, %rcx
+
   popq %rax // Pop 'value'.
 
   // Restore the callee-save registers.
@@ -120,7 +155,15 @@ ENTRY(siglongjmp)
   movq (_JB_RSP * 8)(%r12),%rsp
   movq (_JB_PC  * 8)(%r12),%r11
   movq (_JB_R12 * 8)(%r12),%r12
+  m_unmangle_registers %rcx
 
+  // Check the cookie.
+  pushq %rax
+  movq %rcx, %rdi
+  call PIC_PLT(__bionic_setjmp_cookie_check)
+  popq %rax
+
+  // Return 1 if value is 0.
   testl %eax,%eax
   jnz 1f
   incl %eax