diff options
Diffstat (limited to 'arch/x86/um/shared/sysdep/stub_64.h')
| -rw-r--r-- | arch/x86/um/shared/sysdep/stub_64.h | 36 |
1 files changed, 24 insertions, 12 deletions
diff --git a/arch/x86/um/shared/sysdep/stub_64.h b/arch/x86/um/shared/sysdep/stub_64.h index b7b8b8e4359d..6e2626b77a2e 100644 --- a/arch/x86/um/shared/sysdep/stub_64.h +++ b/arch/x86/um/shared/sysdep/stub_64.h @@ -7,8 +7,8 @@ #define __SYSDEP_STUB_H #include <sysdep/ptrace_user.h> +#include <generated/asm-offsets.h> -#define STUB_SYSCALL_RET PT_INDEX(RAX) #define STUB_MMAP_NR __NR_mmap #define MMAP_OFFSET(o) (o) @@ -82,18 +82,30 @@ static inline void trap_myself(void) __asm("int3"); } -static inline void remap_stack(long fd, unsigned long offset) +static inline void remap_stack_and_trap(void) { - __asm__ volatile ("movq %4,%%r10 ; movq %5,%%r8 ; " - "movq %6, %%r9; " __syscall "; movq %7, %%rbx ; " - "movq %%rax, (%%rbx)": - : "a" (STUB_MMAP_NR), "D" (STUB_DATA), - "S" (UM_KERN_PAGE_SIZE), - "d" (PROT_READ | PROT_WRITE), - "g" (MAP_FIXED | MAP_SHARED), "g" (fd), - "g" (offset), - "i" (&((struct stub_data *) STUB_DATA)->child_err) - : __syscall_clobber, "r10", "r8", "r9" ); + __asm__ volatile ( + "movq %0,%%rax ;" + "movq %%rsp,%%rdi ;" + "andq %1,%%rdi ;" + "movq %2,%%r10 ;" + "movq %%rdi,%%r8 ; addq %3,%%r8 ; movq (%%r8),%%r8 ;" + "movq %%rdi,%%r9 ; addq %4,%%r9 ; movq (%%r9),%%r9 ;" + __syscall ";" + "movq %%rsp,%%rdi ; andq %1,%%rdi ;" + "addq %5,%%rdi ; movq %%rax, (%%rdi) ;" + "int3" + : : + "g" (STUB_MMAP_NR), + "g" (~(UM_KERN_PAGE_SIZE - 1)), + "g" (MAP_FIXED | MAP_SHARED), + "g" (UML_STUB_FIELD_FD), + "g" (UML_STUB_FIELD_OFFSET), + "g" (UML_STUB_FIELD_CHILD_ERR), + "S" (UM_KERN_PAGE_SIZE), + "d" (PROT_READ | PROT_WRITE) + : + __syscall_clobber, "r10", "r8", "r9"); } #endif |