SEGV in Bison at parse-gram.y:244

[Youngseok Choi]

Hello,

We are developing a new fuzzer, and it found a SEGV error in bison 3.8.2.

Stack Trace

==12263==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 
0x7f5b51624306 bp 0x000000000000 sp 0x7ffe4b88e6a8 T0)
==12263==The signal is caused by a READ memory access.
==12263==Hint: address points to the zero page.
    #0 0x7f5b51624305  (/lib/x86_64-linux-gnu/libc.so.6+0xb1305)
    #1 0x7f5b515fd5f4 in fputs_unlocked 
(/lib/x86_64-linux-gnu/libc.so.6+0x8a5f4)
    #2 0x556acb7e54e7 in yy_symbol_value_print src/parse-gram.y:244
    #3 0x556acb7e5d7b in yy_symbol_print src/parse-gram.c:1392
    #4 0x556acb7edb4a in gram_parse src/parse-gram.c:2966
    #5 0x556acb8077e3 in reader src/reader.c:766
    #6 0x556acb7b2be0 in main src/main.c:118

Steps to Reproduce

We configured and built bison with address sanitizer:

CFLAGS="-fsanitize=address -g -O0" ./configure
make -j

Then, run bison with:

./bison <attached_file> -T

Environment
- OS: Ubuntu 18.04.1
- gcc 7.5.0
- bison: 3.8.2

Many Thanks,
Youngseok Choi

bison_input_poc1.zip
Description: Zip archive