1 files changed, 16 insertions, 3 deletions

diff --git a/arch/i386/oprofile/backtrace.c b/arch/i386/oprofile/backtrace.c
index acc18138fb22..c049ce414f01 100644
--- a/arch/i386/oprofile/backtrace.c
+++ b/arch/i386/oprofile/backtrace.c
@@ -20,7 +20,20 @@ struct frame_head {
 } __attribute__((packed));
 
 static struct frame_head *
-dump_backtrace(struct frame_head * head)
+dump_kernel_backtrace(struct frame_head * head)
+{
+        oprofile_add_trace(head->ret);
+
+        /* frame pointers should strictly progress back up the stack
+         * (towards higher addresses) */
+        if (head >= head->ebp)
+                return NULL;
+
+        return head->ebp;
+}
+
+static struct frame_head *
+dump_user_backtrace(struct frame_head * head)
 {
         struct frame_head bufhead[2];
 
@@ -105,10 +118,10 @@ x86_backtrace(struct pt_regs * const regs, unsigned int depth)
 
         if (!user_mode_vm(regs)) {
                 while (depth-- && valid_kernel_stack(head, regs))
-                        head = dump_backtrace(head);
+                        head = dump_kernel_backtrace(head);
                 return;
         }
 
         while (depth-- && head)
-                head = dump_backtrace(head);
+                head = dump_user_backtrace(head);
 }