Crudely limit the use of 'k', 'K', 's' and 'S' when fuzzing.
Change-Id: I8f17b33b746c61bc5ab7ab59ee9e7f8660c2988f
Reviewed-on: https://code-review.googlesource.com/c/re2/+/59272
Reviewed-by: Perry Lorier <perryl@google.com>
Reviewed-by: Paul Wankadia <junyer@google.com>
diff --git a/re2/fuzzing/re2_fuzzer.cc b/re2/fuzzing/re2_fuzzer.cc
index effce50..d796e09 100644
--- a/re2/fuzzing/re2_fuzzer.cc
+++ b/re2/fuzzing/re2_fuzzer.cc
@@ -69,11 +69,15 @@
// generating such patterns that fall within the other limits, but result
// in timeouts nonetheless. The marginal cost is high - even more so when
// counted repetition is involved - whereas the marginal benefit is zero.
+ // Crudely limit the use of 'k', 'K', 's' and 'S' too because they become
+ // three-element character classes when case-insensitive and using UTF-8.
// TODO(junyer): Handle [:isalnum:] et al. when they start to cause pain.
int char_class = 0;
int backslash_p = 0; // very expensive, so handle specially
for (size_t i = 0; i < pattern.size(); i++) {
- if (pattern[i] == '.')
+ if (pattern[i] == '.' ||
+ pattern[i] == 'k' || pattern[i] == 'K' ||
+ pattern[i] == 's' || pattern[i] == 'S')
char_class++;
if (pattern[i] != '\\')
continue;
