From 8a5f4f2ebe7f35ac5646060fa51e3332f6ef388c Mon Sep 17 00:00:00 2001
From: Nick Clifton <nickc@redhat.com>
Date: Fri, 4 Jan 2019 13:44:34 +0000
Subject: [PATCH] Fix a possible integer overflow problem when examining
 corrupt binaries using a 32-bit binutil.

	PR 24005
	* objdump.c (load_specific_debug_section): Check for integer
	overflow before attempting to allocate contents.

CVE: CVE-2018-20671
Upstream-Status: Backport
[https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=11fa9f134fd658075c6f74499c780df045d9e9ca]

Signed-off-by: Dan Tran <dantran@microsoft.com>
---
 binutils/objdump.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/binutils/objdump.c b/binutils/objdump.c
index f468fcdb59..89ca688938 100644
--- a/binutils/objdump.c
+++ b/binutils/objdump.c
@@ -2503,12 +2503,19 @@ load_specific_debug_section (enum dwarf_section_display_enum debug,
   section->reloc_info = NULL;
   section->num_relocs = 0;
   section->address = bfd_get_section_vma (abfd, sec);
+  section->user_data = sec;
   section->size = bfd_get_section_size (sec);
   amt = section->size + 1;
+  if (amt == 0 || amt > bfd_get_file_size (abfd))
+    {
+      section->start = NULL;
+      free_debug_section (debug);
+      printf (_("\nSection '%s' has an invalid size: %#llx.\n"),
+	      section->name, (unsigned long long) section->size);
+      return FALSE;
+    }
   section->start = contents = malloc (amt);
-  section->user_data = sec;
-  if (amt == 0
-      || section->start == NULL
+  if (section->start == NULL
       || !bfd_get_full_section_contents (abfd, sec, &contents))
     {
       free_debug_section (debug);
-- 
2.22.0.vfs.1.1.57.gbaf16c8

