From d6cf5c674952d5ae3463d9b580dac6559576deac Mon Sep 17 00:00:00 2001 From: Jeff Epler Date: Sat, 31 Mar 2018 21:27:56 -0500 Subject: [PATCH] py/objstr: In find/rfind, don't crash when end < start. --- py/objstr.c | 5 +++++ tests/basics/string_find.py | 1 + tests/basics/string_rfind.py | 1 + 3 files changed, 7 insertions(+) diff --git a/py/objstr.c b/py/objstr.c index 0b11533f82..da925234e2 100644 --- a/py/objstr.c +++ b/py/objstr.c @@ -699,8 +699,13 @@ STATIC mp_obj_t str_finder(size_t n_args, const mp_obj_t *args, int direction, b end = str_index_to_ptr(self_type, haystack, haystack_len, args[3], true); } + if (end < start) { + goto out_error; + } + const byte *p = find_subbytes(start, end - start, needle, needle_len, direction); if (p == NULL) { + out_error: // not found if (is_index) { mp_raise_ValueError("substring not found"); diff --git a/tests/basics/string_find.py b/tests/basics/string_find.py index 4a206eb0e0..f9fcad3e57 100644 --- a/tests/basics/string_find.py +++ b/tests/basics/string_find.py @@ -21,6 +21,7 @@ print("0000".find('-1', 3)) print("0000".find('1', 3)) print("0000".find('1', 4)) print("0000".find('1', 5)) +print("aaaaaaaaaaa".find("bbb", 9, 2)) try: 'abc'.find(1) diff --git a/tests/basics/string_rfind.py b/tests/basics/string_rfind.py index 4d0e84018f..54269d6f59 100644 --- a/tests/basics/string_rfind.py +++ b/tests/basics/string_rfind.py @@ -21,3 +21,4 @@ print("0000".rfind('-1', 3)) print("0000".rfind('1', 3)) print("0000".rfind('1', 4)) print("0000".rfind('1', 5)) +print("aaaaaaaaaaa".rfind("bbb", 9, 2))