Merge tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

[linux-2.6-microblaze.git] / arch / x86 / include / asm / thread_info.h

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 89bff04..8b7c8d8 100644 (file)
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -176,6 +176,50 @@ static inline unsigned long current_stack_pointer(void)
        return sp;
 }
 
+/*
+ * Walks up the stack frames to make sure that the specified object is
+ * entirely contained by a single stack frame.
+ *
+ * Returns:
+ *              1 if within a frame
+ *             -1 if placed across a frame boundary (or outside stack)
+ *              0 unable to determine (no frame pointers, etc)
+ */
+static inline int arch_within_stack_frames(const void * const stack,
+                                          const void * const stackend,
+                                          const void *obj, unsigned long len)
+{
+#if defined(CONFIG_FRAME_POINTER)
+       const void *frame = NULL;
+       const void *oldframe;
+
+       oldframe = __builtin_frame_address(1);
+       if (oldframe)
+               frame = __builtin_frame_address(2);
+       /*
+        * low ----------------------------------------------> high
+        * [saved bp][saved ip][args][local vars][saved bp][saved ip]
+        *                     ^----------------^
+        *               allow copies only within here
+        */
+       while (stack <= frame && frame < stackend) {
+               /*
+                * If obj + len extends past the last frame, this
+                * check won't pass and the next frame will be 0,
+                * causing us to bail out and correctly report
+                * the copy as invalid.
+                */
+               if (obj + len <= frame)
+                       return obj >= oldframe + 2 * sizeof(void *) ? 1 : -1;
+               oldframe = frame;
+               frame = *(const void * const *)frame;
+       }
+       return -1;
+#else
+       return 0;
+#endif
+}
+
 #else /* !__ASSEMBLY__ */
 
 #ifdef CONFIG_X86_64
@@ -219,32 +263,11 @@ static inline unsigned long current_stack_pointer(void)
  * have to worry about atomic accesses.
  */
 #define TS_COMPAT              0x0002  /* 32bit syscall active (64BIT)*/
-#define TS_RESTORE_SIGMASK     0x0008  /* restore signal mask in do_signal() */
+#ifdef CONFIG_COMPAT
+#define TS_I386_REGS_POKED     0x0004  /* regs poked by 32-bit ptracer */
+#endif
 
 #ifndef __ASSEMBLY__
-#define HAVE_SET_RESTORE_SIGMASK       1
-static inline void set_restore_sigmask(void)
-{
-       struct thread_info *ti = current_thread_info();
-       ti->status |= TS_RESTORE_SIGMASK;
-       WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
-}
-static inline void clear_restore_sigmask(void)
-{
-       current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
-}
-static inline bool test_restore_sigmask(void)
-{
-       return current_thread_info()->status & TS_RESTORE_SIGMASK;
-}
-static inline bool test_and_clear_restore_sigmask(void)
-{
-       struct thread_info *ti = current_thread_info();
-       if (!(ti->status & TS_RESTORE_SIGMASK))
-               return false;
-       ti->status &= ~TS_RESTORE_SIGMASK;
-       return true;
-}
 
 static inline bool in_ia32_syscall(void)
 {