From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Fri, 22 Jun 2012 21:54:43 +0000 (+0200)
Subject: 	* grub-core/kern/mm.c (get_header_from_pointer): Put a more informative
X-Git-Tag: 2.00~29
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3988c4a09fe26ffb917ce07170a6fb78654b64db;p=thirdparty%2Fgrub.git

	* grub-core/kern/mm.c (get_header_from_pointer): Put a more informative
	message on double free. Put the value of magic in case of mismatch.
---

diff --git a/ChangeLog b/ChangeLog
index 3b0d41a6f..5f823b9e1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2012-06-22  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/kern/mm.c (get_header_from_pointer): Put a more informative
+	message on double free. Put the value of magic in case of mismatch.
+
 2012-06-22  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Speed-up video on yeeloong.
diff --git a/grub-core/kern/mm.c b/grub-core/kern/mm.c
index 95dd5ddf1..7f240779f 100644
--- a/grub-core/kern/mm.c
+++ b/grub-core/kern/mm.c
@@ -98,8 +98,11 @@ get_header_from_pointer (void *ptr, grub_mm_header_t *p, grub_mm_region_t *r)
     grub_fatal ("out of range pointer %p", ptr);
 
   *p = (grub_mm_header_t) ptr - 1;
+  if ((*p)->magic == GRUB_MM_FREE_MAGIC)
+    grub_fatal ("double free at %p", *p);
   if ((*p)->magic != GRUB_MM_ALLOC_MAGIC)
-    grub_fatal ("alloc magic is broken at %p", *p);
+    grub_fatal ("alloc magic is broken at %p: %lx", *p,
+		(unsigned long) (*p)->magic);
 }
 
 /* Initialize a region starting from ADDR and whose size is SIZE,