/usr/src/binutils/patches/pr22894.diff is in binutils-source 2.30-15ubuntu1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 | # 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.
---
bfd/ChangeLog | 6 ++++++
bfd/dwarf1.c | 17 +++++++++++++++--
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/bfd/dwarf1.c b/bfd/dwarf1.c
index 71bc57b..f272ea8 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:
--
2.9.3
|