Created attachment 12456 [details] PoC for a Double Free bug Hi, An double free was discovered in readelf (the latest commit f717994) in process_symbol_table(), via a crafted file. To reproduce: readelf -a PoC. ASAN says: ==23637==ERROR: AddressSanitizer: attempting double-free on 0x60200000eef0 in thread T0: #0 0x7f6f6a79632a in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x9832a) #1 0x4423c3 in process_symbol_table ../../binutils/readelf.c:12201 #2 0x4619d2 in process_object ../../binutils/readelf.c:20124 #3 0x463527 in process_file ../../binutils/readelf.c:20602 #4 0x463941 in main ../../binutils/readelf.c:20671 #5 0x7f6f6a35482f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f) #6 0x402808 in _start (/home/dungnguyen/PoCs/readelf/readelf+0x402808) 0x60200000eef0 is located 0 bytes inside of 1-byte region [0x60200000eef0,0x60200000eef1) freed by thread T0 here: #0 0x7f6f6a79632a in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x9832a) #1 0x438faa in get_num_dynamic_syms ../../binutils/readelf.c:9999 #2 0x43a19c in process_dynamic_section ../../binutils/readelf.c:10273 #3 0x46198f in process_object ../../binutils/readelf.c:20114 #4 0x463527 in process_file ../../binutils/readelf.c:20602 #5 0x463941 in main ../../binutils/readelf.c:20671 #6 0x7f6f6a35482f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f) previously allocated by thread T0 here: #0 0x7f6f6a796662 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98662) #1 0x4ddbca in xmalloc ../../libiberty/xmalloc.c:147 #2 0x49dab6 in cmalloc ../../binutils/dwarf.c:9898 #3 0x438a3e in get_dynamic_data ../../binutils/readelf.c:9923 #4 0x438f58 in get_num_dynamic_syms ../../binutils/readelf.c:9987 #5 0x43a19c in process_dynamic_section ../../binutils/readelf.c:10273 #6 0x46198f in process_object ../../binutils/readelf.c:20114 #7 0x463527 in process_file ../../binutils/readelf.c:20602 #8 0x463941 in main ../../binutils/readelf.c:20671 #9 0x7f6f6a35482f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f) Thanks, Manh Dung
This is the recent 10ca4b042d1 commit
The master branch has been updated by Alan Modra <amodra@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=c98a4545dc7bf2bcaf1de539c4eb84784680eaa4 commit c98a4545dc7bf2bcaf1de539c4eb84784680eaa4 Author: Alan Modra <amodra@gmail.com> Date: Wed Apr 15 12:39:54 2020 +0930 Re: readelf: Consolidate --syms --use-dynamic with --dyn-syms PR 25821 * readelf.c (get_num_dynamic_syms): Typo fix.
Patch applied.