libpthread-330.220.2.tar.gz

[apple/libpthread.git] / src / pthread_asm.s

diff --git a/src/pthread_asm.s b/src/pthread_asm.s
index b69176334ce87ee0a1d06eb8c13b96b9e4518349..90afe461bfec6a8168ae7a1c616940160d91f9d8 100644 (file)
--- a/src/pthread_asm.s
+++ b/src/pthread_asm.s
@@ -21,19 +21,12 @@
  * @APPLE_LICENSE_HEADER_END@
  */
 
+#include "offsets.h"
+
 #if defined(__x86_64__)
 
 #include <mach/i386/syscall_sw.h>
 
-       .text
-       .align 2, 0x90
-       .globl ___pthread_set_self
-___pthread_set_self:
-       movl    $0, %esi        // 0 as the second argument
-       movl    $ SYSCALL_CONSTRUCT_MDEP(3), %eax       // Machine-dependent syscall number 3
-       MACHDEP_SYSCALL_TRAP
-       ret
-
 #ifndef VARIANT_DYLD
 
        .align 2, 0x90
@@ -58,23 +51,57 @@ _thread_start:
        leave
        ret
 
+       .align 2, 0x90
+       .globl _thread_chkstk_darwin
+_thread_chkstk_darwin:
+       .globl ____chkstk_darwin
+____chkstk_darwin: // %rax == alloca size
+       pushq  %rcx
+       leaq   0x10(%rsp), %rcx
+
+       // validate that the frame pointer is on our stack (no alt stack)
+       cmpq   %rcx, %gs:_PTHREAD_STRUCT_DIRECT_STACKADDR_OFFSET
+       jb     Lprobe
+       cmpq   %rcx, %gs:_PTHREAD_STRUCT_DIRECT_STACKBOTTOM_OFFSET
+       jae    Lprobe
+
+       // validate alloca size
+       subq   %rax, %rcx
+       jb     Lcrash
+       cmpq   %rcx, %gs:_PTHREAD_STRUCT_DIRECT_STACKBOTTOM_OFFSET
+       ja     Lcrash
+
+       popq   %rcx
+       retq
+
+Lprobe:
+       // probe the stack when it's not ours (altstack or some shenanigan)
+       cmpq   $0x1000, %rax
+       jb     Lend
+       pushq  %rax
+Lloop:
+       subq   $0x1000, %rcx
+       testq  %rcx, (%rcx)
+       subq   $0x1000, %rax
+       cmpq   $0x1000, %rax
+       ja     Lloop
+       popq   %rax
+Lend:
+       subq   %rax, %rcx
+       testq  %rcx, (%rcx)
+
+       popq   %rcx
+       retq
+
+Lcrash:
+       ud2
+
 #endif
 
 #elif defined(__i386__)
 
 #include <mach/i386/syscall_sw.h>
 
-       .text
-       .align 2, 0x90
-       .globl ___pthread_set_self
-___pthread_set_self:
-       pushl   4(%esp)
-       pushl   $0
-       movl    $3,%eax
-       MACHDEP_SYSCALL_TRAP
-       addl    $8,%esp
-       ret
-
 #ifndef VARIANT_DYLD
 
        .align 2, 0x90
@@ -111,22 +138,62 @@ _thread_start:
        leave
        ret
 
+       .align 2, 0x90
+       .globl _thread_chkstk_darwin
+_thread_chkstk_darwin:
+       .globl ____chkstk_darwin
+____chkstk_darwin: // %eax == alloca size
+       pushl  %ecx
+       pushl  %edx
+       leal   0xc(%esp), %ecx
+
+       // validate that the frame pointer is on our stack (no alt stack)
+       movl   %gs:0x0, %edx    // pthread_self()
+       cmpl   %ecx, _PTHREAD_STRUCT_DIRECT_STACKADDR_OFFSET(%edx)
+       jb     Lprobe
+       movl   _PTHREAD_STRUCT_DIRECT_STACKBOTTOM_OFFSET(%edx), %edx
+       cmpl   %ecx, %edx
+       jae    Lprobe
+
+       // validate alloca size
+       subl   %eax, %ecx
+       jb     Lcrash
+       cmpl   %ecx, %edx
+       ja     Lcrash
+
+       popl   %edx
+       popl   %ecx
+       retl
+
+Lprobe:
+       // probe the stack when it's not ours (altstack or some shenanigan)
+       cmpl   $0x1000, %eax
+       jb     Lend
+       pushl  %eax
+Lloop:
+       subl   $0x1000, %ecx
+       testl  %ecx, (%ecx)
+       subl   $0x1000, %eax
+       cmpl   $0x1000, %eax
+       ja     Lloop
+       popl   %eax
+Lend:
+       subl   %eax, %ecx
+       testl  %ecx, (%ecx)
+
+       popl   %edx
+       popl   %ecx
+       retl
+
+Lcrash:
+       ud2
+
 #endif
 
 #elif defined(__arm__)
 
 #include <mach/arm/syscall_sw.h>
 
-       .text
-       .align 2
-       .globl ___pthread_set_self
-___pthread_set_self:
-       /* fast trap for thread_set_cthread */
-       mov     r3, #2
-       mov     r12, #0x80000000
-       swi     #SWI_SYSCALL
-       bx      lr
-
 #ifndef VARIANT_DYLD
 
 // This routine is never called directly by user code, jumped from kernel