1 files changed, 21 insertions, 12 deletions

diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index cfffe3dd9e83..47b0bef335bd 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -100,36 +100,45 @@ asmlinkage void machine_check(void);
 int kstack_depth_to_print = 24;
 static unsigned int code_bytes = 64;
 
-static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
+static inline int valid_stack_ptr(struct thread_info *tinfo, void *p, unsigned size)
 {
         return  p > (void *)tinfo &&
-                p < (void *)tinfo + THREAD_SIZE - 3;
+                p <= (void *)tinfo + THREAD_SIZE - size;
 }
 
+/* The form of the top of the frame on the stack */
+struct stack_frame {
+        struct stack_frame *next_frame;
+        unsigned long return_address;
+};
+
 static inline unsigned long print_context_stack(struct thread_info *tinfo,
                                 unsigned long *stack, unsigned long ebp,
                                 struct stacktrace_ops *ops, void *data)
 {
-        unsigned long addr;
-
 #ifdef  CONFIG_FRAME_POINTER
-        while (valid_stack_ptr(tinfo, (void *)ebp)) {
-                unsigned long new_ebp;
-                addr = *(unsigned long *)(ebp + 4);
+        struct stack_frame *frame = (struct stack_frame *)ebp;
+        while (valid_stack_ptr(tinfo, frame, sizeof(*frame))) {
+                struct stack_frame *next;
+                unsigned long addr;
+
+                addr = frame->return_address;
                 ops->address(data, addr);
                 /*
                  * break out of recursive entries (such as
                  * end_of_stack_stop_unwind_function). Also,
                  * we can never allow a frame pointer to
                  * move downwards!
-                 */
-                new_ebp = *(unsigned long *)ebp;
-                if (new_ebp <= ebp)
+                 */
+                next = frame->next_frame;
+                if (next <= frame)
                         break;
-                ebp = new_ebp;
+                frame = next;
         }
 #else
-        while (valid_stack_ptr(tinfo, stack)) {
+        while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
+                unsigned long addr;
+
                 addr = *stack++;
                 if (__kernel_text_address(addr))
                         ops->address(data, addr);