Dear All, This bug was found with AFLGo, a directed version of AFL/AFLFast. Thanks also to Marcel Böhme and Van-Thuan Pham. This bug was found on Ubuntu 14.04 64-bit & binutils was checked out from main repository at git://sourceware.org/git/binutils-gdb.git. Its commit is a6c21d4a553de184562fd8409a5bcd3f2cc2561a (Wed Apr 19 13:16:05 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: ar d ASAN says: ==148384==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60300000ef98 at pc 0x0000004e7efc bp 0x7ffe38a5e8f0 sp 0x7ffe38a5e8e8 READ of size 8 at 0x60300000ef98 thread T0 #0 0x4e7efb in main /home/ubuntu/binutils-analysis/binutils-gdb/obj-asan/binutils/../../binutils/ar.c:792:12 #1 0x7f0f4a636f44 in __libc_start_main /build/eglibc-oGUzwX/eglibc-2.19/csu/libc-start.c:287 #2 0x4c9fbc in _start (/home/ubuntu/binutils-analysis/binutils-gdb/obj-asan/binutils/ar+0x4c9fbc) VALGRIND says: ==148386== Invalid read of size 8 ==148386== at 0x405F88: main (ar.c:792) ==148386== Address 0x5401838 is 0 bytes after a block of size 24 alloc'd ==148386== at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so) ==148386== by 0x50F27E: xmalloc (xmalloc.c:147) ==148386== by 0x4056FA: decode_options (ar.c:451) ==148386== by 0x405D73: main (ar.c:731) ==148386== ==148386== Syscall param stat(file_name) points to unaddressable byte(s) ==148386== at 0x5126045: _xstat (xstat.c:35) ==148386== by 0x40619D: open_inarch (ar.c:872) ==148386== by 0x405FD5: main (ar.c:797) ==148386== Address 0x0 is not stack'd, malloc'd or (recently) free'd
The master branch has been updated by Alan Modra <amodra@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=7034215fd6d99f275998f7f0f8a346ab35fcbee6 commit 7034215fd6d99f275998f7f0f8a346ab35fcbee6 Author: Alan Modra <amodra@gmail.com> Date: Sun Apr 23 17:28:14 2017 +0930 PR 21417, ar arg check failure PR 21417 * ar.c (main): Check that an archive file is given after options.
Fixed