gdb/gdb-6.5-dwarf-stack-overflow.patch

for gdb/ChangeLog:
2006-08-22  Will Drewry <wad@google.com>
	    Tavis Ormandy <taviso@google.com>

	* dwarf2read.c (decode_locdesc): Enforce location description stack
	boundaries.
	* dwarfread.c (locval): Likewise.

2007-10-15  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Port to GDB-6.7.

Index: gdb-7.1.90.20100711/gdb/dwarf2read.c
===================================================================
--- gdb-7.1.90.20100711.orig/gdb/dwarf2read.c	2010-07-12 10:43:53.000000000 +0200
+++ gdb-7.1.90.20100711/gdb/dwarf2read.c	2010-07-12 10:49:32.000000000 +0200
@@ -11382,8 +11382,7 @@ read_signatured_type (struct objfile *ob
    callers will only want a very basic result and this can become a
    complaint.
 
-   Note that stack[0] is unused except as a default error return.
-   Note that stack overflow is not yet handled.  */
+   Note that stack[0] is unused except as a default error return. */
 
 static CORE_ADDR
 decode_locdesc (struct dwarf_block *blk, struct dwarf2_cu *cu)
@@ -11399,7 +11398,7 @@ decode_locdesc (struct dwarf_block *blk,
 
   i = 0;
   stacki = 0;
-  stack[stacki] = 0;
+  stack[++stacki] = 0;
 
   while (i < size)
     {
@@ -11581,6 +11580,16 @@ decode_locdesc (struct dwarf_block *blk,
 		     dwarf_stack_op_name (op, 1));
 	  return (stack[stacki]);
 	}
+      /* Enforce maximum stack depth of size-1 to avoid ++stacki writing
+         outside of the allocated space. Also enforce minimum > 0.
+         -- wad@google.com 14 Aug 2006 */
+      if (stacki >= sizeof (stack) / sizeof (*stack) - 1)
+	internal_error (__FILE__, __LINE__,
+	                _("location description stack too deep: %d"),
+	                stacki);
+      if (stacki <= 0)
+	internal_error (__FILE__, __LINE__,
+	                _("location description stack too shallow"));
     }
   return (stack[stacki]);
 }