blob: 325c339b886012e6e9d5bf39e075cc31a0185bdd [file] [log] [blame]
Brad Bishop1a4b7ee2018-12-16 17:11:34 -08001From 45a0eaf77022963d639d6d19871dbab7b79703fc Mon Sep 17 00:00:00 2001
2From: Alan Modra <amodra@gmail.com>
3Date: Tue, 23 Oct 2018 19:02:06 +1030
4Subject: [PATCH] PR23806, NULL pointer dereference in merge_strings
5
6 PR 23806
7 * merge.c (_bfd_add_merge_section): Don't attempt to merge
8 sections with ridiculously large alignments.
9
10Upstream-Status: Backport
11CVE: CVE-2018-18606
12Signed-off-by: Zhixiong Chi <zhixiong.chi@windriver.com>
13---
14 bfd/ChangeLog | 6 ++++++
15 bfd/merge.c | 15 +++++++++++----
16 2 files changed, 17 insertions(+), 4 deletions(-)
17
Brad Bishop1a4b7ee2018-12-16 17:11:34 -080018--- a/bfd/merge.c
19+++ b/bfd/merge.c
20@@ -24,6 +24,7 @@
21 as used in ELF SHF_MERGE. */
22
23 #include "sysdep.h"
24+#include <limits.h>
25 #include "bfd.h"
26 #include "elf-bfd.h"
27 #include "libbfd.h"
Brad Bishop977dc1a2019-02-06 16:01:43 -050028@@ -385,12 +386,18 @@ _bfd_add_merge_section (bfd *abfd, void
Brad Bishop1a4b7ee2018-12-16 17:11:34 -080029 return TRUE;
30 }
31
32- align = sec->alignment_power;
33- if ((sec->entsize < (unsigned) 1 << align
34+#ifndef CHAR_BIT
35+#define CHAR_BIT 8
36+#endif
37+ if (sec->alignment_power >= sizeof (align) * CHAR_BIT)
38+ return TRUE;
39+
40+ align = 1u << sec->alignment_power;
41+ if ((sec->entsize < align
42 && ((sec->entsize & (sec->entsize - 1))
43 || !(sec->flags & SEC_STRINGS)))
44- || (sec->entsize > (unsigned) 1 << align
45- && (sec->entsize & (((unsigned) 1 << align) - 1))))
46+ || (sec->entsize > align
47+ && (sec->entsize & (align - 1))))
48 {
49 /* Sanity check. If string character size is smaller than
50 alignment, then we require character size to be a power