https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88783
Bug ID: 88783
Summary: integer overflow in libiberty, heap overflow will be
triggered
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: demangler
Assignee: unassigned at gcc dot gnu.org
Reporter: tfx_sec at hotmail dot com
Target Milestone: ---
Created attachment 45396
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45396&action=edit
nm -C POC
nm -C POC
I use 32bit binutils in 64bit Ubuntu 16.04.4 LTS.
The trigger command is ./nm -C POC
The source Code show as follow in cplus-dem.c
>2246 work->tmpl_argvec = XNEWVEC (char *, r); //sizeof(char*) * r
>2247 work->ntmpl_args = r;
>2248 for (i = 0; i < r; i++)
>2249 work->tmpl_argvec[i] = 0;
Integer overflow when r > 0x40000000 in line 2246, that will trigger heap
overflow in in line 2249.
There are several similar problems in libiberty.
The part of crash output show as follow.
=================================================================
==9029==ERROR: AddressSanitizer: heap-buffer-overflow on address 0xf3bfea80 at
pc 0x083ba887 bp 0xffabcac8 sp 0xffabcac0
WRITE of size 4 at 0xf3bfea80 thread T0
#0 0x83ba886 in demangle_template
./binutils-gdb/libiberty/./cplus-dem.c:2249:23
#1 0x83b8c2e in demangle_signature
./binutils-gdb/libiberty/./cplus-dem.c:1709:18
#2 0x83b62da in internal_cplus_demangle
./binutils-gdb/libiberty/./cplus-dem.c:1258:14
#3 0x83b5143 in cplus_demangle ./binutils-gdb/libiberty/./cplus-dem.c:919:9
#4 0x815d092 in bfd_demangle ./binutils-gdb/bfd/bfd.c:2254:9
#5 0x81460a0 in print_symname ./binutils-gdb/binutils/nm.c:423:19
#6 0x8145035 in print_symbol_info_bsd ./binutils-gdb/binutils/nm.c:1565:3
#7 0x8149d87 in print_symbol ./binutils-gdb/binutils/nm.c:903:3
#8 0x8148828 in print_symbols ./binutils-gdb/binutils/nm.c:1102:7
#9 0x8146fdb in display_rel_file ./binutils-gdb/binutils/nm.c:1215:5
#10 0x8144a11 in display_file ./binutils-gdb/binutils/nm.c:1335:7
#11 0x814424f in main ./binutils-gdb/binutils/nm.c:1816:12
#12 0xf7d3f636 in __libc_start_main (/lib/i386-linux-gnu/libc.so.6+0x18636)
#13 0x806be08 in _start (./binutils-gdb/binutils/nm-new+0x806be08)
0xf3bfea80 is located 0 bytes to the right of 251581056-byte region
[0xe4c11800,0xf3bfea80)
allocated by thread T0 here:
#0 0x8112215 in malloc asan_malloc_linux.cc:146:3
#1 0x83e6659 in xmalloc ./binutils-gdb/libiberty/./xmalloc.c:147:12
#2 0x83b8c2e in demangle_signature
./binutils-gdb/libiberty/./cplus-dem.c:1709:18
#3 0x83b62da in internal_cplus_demangle
./binutils-gdb/libiberty/./cplus-dem.c:1258:14
#4 0x83b5143 in cplus_demangle ./binutils-gdb/libiberty/./cplus-dem.c:919:9
#5 0x815d092 in bfd_demangle ./binutils-gdb/bfd/bfd.c:2254:9
SUMMARY: AddressSanitizer: heap-buffer-overflow
./binutils-gdb/libiberty/./cplus-dem.c:2249:23 in demangle_template
Shadow bytes around the buggy address:
0x3e77fd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x3e77fd10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x3e77fd20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x3e77fd30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x3e77fd40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x3e77fd50:[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x3e77fd60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x3e77fd70: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x3e77fd80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x3e77fd90: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x3e77fda0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
Shadow gap: cc
==9029==ABORTING
