https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99688
Bug ID: 99688 Summary: AddressSanitizer: stack-buffer-overflow on address at gfc_match_name(char*) gcc/fortran/match.c:685 Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran Assignee: unassigned at gcc dot gnu.org Reporter: marxin at gcc dot gnu.org Blocks: 86656 Target Milestone: --- I see the following ASAN issue: $ ./xgcc -B. /home/marxin/Programming/gcc/gcc/testsuite/gfortran.dg/pr95828.f90 -c ================================================================= ==28113==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffffffd3af at pc 0x000000ba5a30 bp 0x7fffffffd080 sp 0x7fffffffd078 WRITE of size 1 at 0x7fffffffd3af thread T0 #0 0xba5a2f in gfc_match_name(char*) /home/marxin/Programming/gcc2/gcc/fortran/match.c:685 #1 0xba7af8 in gfc_match(char const*, ...) /home/marxin/Programming/gcc2/gcc/fortran/match.c:1186 #2 0xbc4846 in gfc_match_select_rank() /home/marxin/Programming/gcc2/gcc/fortran/match.c:6654 #3 0xc3db48 in match_word /home/marxin/Programming/gcc2/gcc/fortran/parse.c:65 #4 0xc3f4bd in decode_statement /home/marxin/Programming/gcc2/gcc/fortran/parse.c:429 #5 0xc46cce in next_free /home/marxin/Programming/gcc2/gcc/fortran/parse.c:1316 #6 0xc478b8 in next_statement /home/marxin/Programming/gcc2/gcc/fortran/parse.c:1548 #7 0xc4fd5b in parse_spec /home/marxin/Programming/gcc2/gcc/fortran/parse.c:3967 #8 0xc58f22 in parse_progunit /home/marxin/Programming/gcc2/gcc/fortran/parse.c:5896 #9 0xc5851c in parse_contained /home/marxin/Programming/gcc2/gcc/fortran/parse.c:5797 #10 0xc5a10c in parse_module /home/marxin/Programming/gcc2/gcc/fortran/parse.c:6170 #11 0xc5c26c in gfc_parse_file() /home/marxin/Programming/gcc2/gcc/fortran/parse.c:6465 #12 0xd76343 in gfc_be_parse_file /home/marxin/Programming/gcc2/gcc/fortran/f95-lang.c:212 #13 0x229bd2e in compile_file /home/marxin/Programming/gcc2/gcc/toplev.c:457 #14 0x22a50ef in do_compile /home/marxin/Programming/gcc2/gcc/toplev.c:2201 #15 0x22a5953 in toplev::main(int, char**) /home/marxin/Programming/gcc2/gcc/toplev.c:2340 #16 0x4c85cad in main /home/marxin/Programming/gcc2/gcc/main.c:39 #17 0x7ffff7095b24 in __libc_start_main ../csu/libc-start.c:332 #18 0xa349ed in _start (/home/marxin/Programming/gcc2/objdir/gcc/f951+0xa349ed) Address 0x7fffffffd3af is located in stack of thread T0 at offset 191 in frame #0 0xbc4644 in gfc_match_select_rank() /home/marxin/Programming/gcc2/gcc/fortran/match.c:6634 This frame has 4 object(s): [32, 40) 'expr1' (line 6635) [64, 72) 'expr2' (line 6635) [96, 104) 'ns' (line 6639) [128, 191) 'name' (line 6637) <== Memory access at offset 191 overflows this variable HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork (longjmp and C++ exceptions *are* supported) SUMMARY: AddressSanitizer: stack-buffer-overflow /home/marxin/Programming/gcc2/gcc/fortran/match.c:685 in gfc_match_name(char*) Shadow bytes around the buggy address: 0x10007fff7a20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 0x10007fff7a30: f1 f1 00 00 f2 f2 00 00 00 f3 f3 f3 f3 f3 00 00 0x10007fff7a40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x10007fff7a50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 0x10007fff7a60: f1 f1 00 f2 f2 f2 00 f2 f2 f2 00 f2 f2 f2 00 00 =>0x10007fff7a70: 00 00 00 00 00[07]f3 f3 f3 f3 00 00 00 00 00 00 0x10007fff7a80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 0x10007fff7a90: 04 f2 04 f2 00 00 f3 f3 00 00 00 00 00 00 00 00 0x10007fff7aa0: f1 f1 f1 f1 f1 f1 04 f2 04 f3 f3 f3 00 00 00 00 0x10007fff7ab0: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00 0x10007fff7ac0: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 f2 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 ==28113==ABORTING Referenced Bugs: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86656 [Bug 86656] [meta-bug] Issues found with -fsanitize=address