From: Matthias Klose <doko@debian.org>
Date: Sun, 18 Mar 2018 04:51:40 +0000 (+0000)
Subject: pr22894
X-Git-Tag: archive/raspbian/2.30-8+rpi1^2~6
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=4be44720f5d0c5e7b7139482685948126c2dcf28;p=binutils.git

pr22894

# DP: Fix potential integer overflow when reading corrupt dwarf1

From eef104664efb52965d85a28bc3fc7c77e52e48e2 Mon Sep 17 00:00:00 2001
From: Nick Clifton <nickc@redhat.com>
Date: Wed, 28 Feb 2018 10:13:54 +0000
Subject: [PATCH] Fix potential integer overflow when reading corrupt dwarf1
 debug information.

	PR 22894
	* dwarf1.c (parse_die): Check the length of form blocks before
	advancing the data pointer.

Gbp-Pq: Name pr22894.diff
---

diff --git a/bfd/dwarf1.c b/bfd/dwarf1.c
index 71bc57bfd..f272ea831 100644
--- a/bfd/dwarf1.c
+++ b/bfd/dwarf1.c
@@ -213,6 +213,7 @@ parse_die (bfd *	     abfd,
   /* Then the attributes.  */
   while (xptr + 2 <= aDiePtrEnd)
     {
+      unsigned int   block_len;
       unsigned short attr;
 
       /* Parse the attribute based on its form.  This section
@@ -255,12 +256,24 @@ parse_die (bfd *	     abfd,
 	  break;
 	case FORM_BLOCK2:
 	  if (xptr + 2 <= aDiePtrEnd)
-	    xptr += bfd_get_16 (abfd, xptr);
+	    {
+	      block_len = bfd_get_16 (abfd, xptr);
+	      if (xptr + block_len > aDiePtrEnd
+		  || xptr + block_len < xptr)
+		return FALSE;
+	      xptr += block_len;
+	    }
 	  xptr += 2;
 	  break;
 	case FORM_BLOCK4:
 	  if (xptr + 4 <= aDiePtrEnd)
-	    xptr += bfd_get_32 (abfd, xptr);
+	    {
+	      block_len = bfd_get_32 (abfd, xptr);
+	      if (xptr + block_len > aDiePtrEnd
+		  || xptr + block_len < xptr)
+		return FALSE;
+	      xptr += block_len;
+	    }
 	  xptr += 4;
 	  break;
 	case FORM_STRING: