Description of problem: The vulnerability was triggered in function parse_ref() at src/scan-code.l:450. Version-Release number of selected component (if applicable): <= latest version How reproducible: ./bison POC2 Steps to Reproduce: The information is as follows: $./bison POC2 id:000006,sig:11,src:001158,op:arith8,pos:33,val:+27:1.5: error: symbol S is used, but is not defined as a token and has no rules %%D:S{’?<:p{$}EEE@->$<p{$}EE>[%>\:}D%%H:￡{ ^ Segmentation fault The ASAN debugging information is as follows: $./bison POC2 id:000006,sig:11,src:001158,op:arith8,pos:33,val:+27:1.5: error: symbol S is used, but is not defined as a token and has no rules %%D:S{?ˉ?<:p{$}EEE@->$<p{$}EE>[%>\:}D%%H:?{ ^ ================================================================= ==52395==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60400000d634 at pc 0x000000579aa9 bp 0x7ffda0f6e010 sp 0x7ffda0f6e008 READ of size 1 at 0x60400000d634 thread T0 #0 0x579aa8 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x579aa8) #1 0x576498 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x576498) #2 0x570ae0 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x570ae0) #3 0x563e96 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x563e96) #4 0x51a2c6 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x51a2c6) #5 0x7fc68f1d4abf (/lib/x86_64-linux-gnu/libc.so.6+0x20abf) #6 0x43ced8 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x43ced8) 0x60400000d634 is located 0 bytes to the right of 36-byte region [0x60400000d610,0x60400000d634) allocated by thread T0 here: #0 0x4c3ea2 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x4c3ea2) #1 0x56fb7c (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x56fb7c) #2 0x570ae0 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x570ae0) #3 0x51a2c6 (/home/icy/real/bison-3.0.4-asan/install/bin/bison+0x51a2c6) Shadow bytes around the buggy address: 0x0c087fff9a70: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c087fff9a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c087fff9a90: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c087fff9aa0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c087fff9ab0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa =>0x0c087fff9ac0: fa fa 00 00 00 00[04]fa fa fa fd fd fd fd fd fd 0x0c087fff9ad0: fa fa fd fd fd fd fd fd fa fa fd fd fd fd fd fa 0x0c087fff9ae0: fa fa fd fd fd fd fd fd fa fa fd fd fd fd fd fd 0x0c087fff9af0: fa fa fd fd fd fd fd fd fa fa 00 00 00 00 00 06 0x0c087fff9b00: fa fa fd fd fd fd fd fd fa fa fd fd fd fd fd fd 0x0c087fff9b10: fa fa 00 00 00 00 00 01 fa fa fd fd fd fd fd fd 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 Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 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 ==52395==ABORTING The vulnerability was triggered in function parse_ref() at src/scan-code.l:450. 415 /* Parse named or positional reference. In case of positional 416 references, can return negative values for $-n "deep" stack 417 accesses. */ 418 static long int 419 parse_ref (char *cp, symbol_list *rule, int rule_length, 420 int midrule_rhs_index, char *text, location text_loc, 421 char dollar_or_at) 422 { ... 445 446 if ('[' == *cp) 447 { 448 /* Ignore the brackets. */ 449 char *p; 450 for (p = ++cp; *p != ']'; ++p) 451 continue; 452 cp_end = p; 453 454 explicit_bracketing = true; 455 } Actual results: crash Expected results: crash Additional info: This vulnerability is detected by team OWL337, with our custom fuzzer collAFL. Please contact ganshuitao and chaoz.cn if you need more info about the team, the tool or the vulnerability.
Dear OWL337 Team, Thank you for filing this report. Unfortunately, I cannot find the reproducer that was initially attached to this bug. It seems to have been deleted. I was wondering if you have a copy available. Cheers!
Dear OWL337 Team, Thank you for filing this report. Like I wrote in my earlier comment, I cannot find the reproducer that was initially attached to this bug. It seems to have been deleted. If you have a copy available, please attach and report this upstream, or again here on RH bugzilla. Cheers!