Bug 21147

Summary: readelf - heap buffer overflow, invalid read
Product: binutils Reporter: Thuan Pham <thuanpv>
Component: binutilsAssignee: Not yet assigned to anyone <unassigned>
Status: RESOLVED FIXED    
Severity: normal CC: nickc
Priority: P2    
Version: 2.29   
Target Milestone: ---   
Host: Target:
Build: Last reconfirmed:
Attachments: Bug triggering input

Description Thuan Pham 2017-02-13 10:01:25 UTC
Created attachment 9814 [details]
Bug triggering input

Dear all,

This bug was found with AFLGo, a directed version of AFL/AFLFast. Thanks also to Marcel Böhme. 

This bug was found on Ubuntu 14.04 64-bit & binutils was checkout from main repository at git://sourceware.org/git/binutils-gdb.git. Its commit is 53f7e8ea7fad1fcff1b58f4cbd74e192e0bcbc1d (Fri Feb 10 00:00:16 2017) 

binutils was built with ASAN using gcc-6.2 and clang-3.4. The configure command was:

CC=clang CFLAGS="-DFORTIFY_SOURCE=2 -fstack-protector-all -fsanitize=undefined,address -fno-omit-frame-pointer -g -Wno-error" ../configure --disable-shared --disable-gdb --disable-libdecnumber --disable-readline --disable-sim

To reproduce:
Download the attached file - bug_13
readelf -p 7 bug_13

Valgrind says:
==12826== Invalid read of size 1
==12826==    at 0x423674: process_section_contents (readelf.c:13097)
==12826==    by 0x423674: process_object (readelf.c:16780)
==12826==    by 0x402111: process_file (readelf.c:17154)
==12826==    by 0x402111: main (readelf.c:17225)
==12826==  Address 0x51fd5a8 is 0 bytes after a block of size 8 alloc'd
==12826==    at 0x4C2CC70: calloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==12826==    by 0x406B10: request_dump_bynumber (readelf.c:4298)
==12826==    by 0x406BFA: request_dump (readelf.c:4356)
==12826==    by 0x401D47: parse_args (readelf.c:4449)
==12826==    by 0x401D47: main (readelf.c:17198)


ASAN says:
==3009==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60200000ef58 at pc 0x4e1b6d bp 0x7ffca5290210 sp 0x7ffca5290208
READ of size 1 at 0x60200000ef58 thread T0
    #0 0x4e1b6c in process_section_contents /home/ubuntu/thesis/subjects/binutils-newest/build-asan/binutils/../../binutils/readelf.c:13097
    #1 0x48d610 in process_object /home/ubuntu/thesis/subjects/binutils-newest/build-asan/binutils/../../binutils/readelf.c:16780
    #2 0x488365 in process_file /home/ubuntu/thesis/subjects/binutils-newest/build-asan/binutils/../../binutils/readelf.c:17154
    #3 0x4855c3 in main /home/ubuntu/thesis/subjects/binutils-newest/build-asan/binutils/../../binutils/readelf.c:17225
    #4 0x7f6ce7ee1f44 (/lib/x86_64-linux-gnu/libc.so.6+0x21f44)
    #5 0x47ddfc in _start (/home/ubuntu/thesis/subjects/binutils-newest/build-asan/binutils/readelf+0x47ddfc)
Comment 1 Sourceware Commits 2017-02-13 14:18:19 UTC
The master branch has been updated by Nick Clifton <nickc@sourceware.org>:

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=0ee3043f58aae078a1ecc54b7be2810cae39a718

commit 0ee3043f58aae078a1ecc54b7be2810cae39a718
Author: Nick Clifton <nickc@redhat.com>
Date:   Mon Feb 13 14:17:07 2017 +0000

    Fix access violation when reporting sections that could not be dumped.
    
    	PR binutils/21147
    	* readelf.c (process_section_contents): Fix off by one error
    	reporting un-dumped sections.
Comment 2 Nick Clifton 2017-02-13 14:19:36 UTC
Hi Thuan,

  Thanks for reporting this bug.  I have checked in a small patch to fix it.

  The problem was an off-by-one error when reporting sections which could
  not be dumped.

Cheers
  Nick