From: José Fonseca <jfonseca@vmware.com>
Date: Thu, 30 Apr 2009 12:10:58 +0000 (+0100)
Subject: util: Limit the stack walk to avoid referencing undefined memory.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=be3f9dd26cf59cadc21e4d5cc27dd199c9752b1c;p=mesa.git

util: Limit the stack walk to avoid referencing undefined memory.
---

diff --git a/src/gallium/auxiliary/util/u_debug_stack.c b/src/gallium/auxiliary/util/u_debug_stack.c
index e9891fde8a3..528a1c394be 100644
--- a/src/gallium/auxiliary/util/u_debug_stack.c
+++ b/src/gallium/auxiliary/util/u_debug_stack.c
@@ -62,6 +62,8 @@ debug_backtrace_capture(struct debug_stack_frame *backtrace,
    
 #ifdef PIPE_ARCH_X86
    while(nr_frames) {
+      const void **next_frame_pointer;
+
       if(!frame_pointer)
          break;
       
@@ -72,7 +74,14 @@ debug_backtrace_capture(struct debug_stack_frame *backtrace,
          --nr_frames;
       }
       
-      frame_pointer = (const void **)frame_pointer[0];
+      next_frame_pointer = (const void **)frame_pointer[0];
+      
+      /* Limit the stack walk to avoid referencing undefined memory */
+      if((uintptr_t)next_frame_pointer <= (uintptr_t)frame_pointer ||
+         (uintptr_t)next_frame_pointer > (uintptr_t)frame_pointer + 64*1024)
+         break;
+      
+      frame_pointer = next_frame_pointer;
    }
 #endif