diff options
author | Jonathan Wakely <jwakely@redhat.com> | 2021-09-29 13:48:11 +0100 |
---|---|---|
committer | Jonathan Wakely <jwakely@redhat.com> | 2023-06-23 13:19:24 +0100 |
commit | d877bf3bdf46b5c996505fc247d170e79fbfa4bf (patch) | |
tree | 9e371de82220ce10f07b50e66be72ccae6a96c37 | |
parent | 61dc491950863d0b441ddd3f9d609b83a01deaf7 (diff) |
libstdc++: std::basic_regex should treat '\0' as an ordinary char [PR84110]
When the input sequence contains a _CharT(0) character, the strchr call
in _Scanner<_CharT>::_M_scan_normal() will search for '\0' and so return
a pointer to the terminating null at the end of the string. This makes
the scanner think it's found a special character. Because it doesn't
match any of the actual special characters, we fall off the end of the
function (or assert in debug mode).
We should check for a null character explicitly and either treat it as
an ordinary character (for the ECMAScript grammar) or an error (for all
others). I'm not 100% sure that's right, but it seems consistent with
the POSIX RE rules where a '\0' means the end of the regex pattern or
the end of the sequence being matched.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
PR libstdc++/84110
* include/bits/regex_error.h (regex_constants::_S_null): New
error code for internal use.
* include/bits/regex_scanner.tcc (_Scanner::_M_scan_normal()):
Check for null character.
* testsuite/28_regex/basic_regex/84110.cc: New test.
(cherry picked from commit b701e1f8f6870c0f8cb4050674da489101dd05a5)
-rw-r--r-- | libstdc++-v3/include/bits/regex_error.h | 1 | ||||
-rw-r--r-- | libstdc++-v3/include/bits/regex_scanner.tcc | 10 | ||||
-rw-r--r-- | libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc | 39 |
3 files changed, 50 insertions, 0 deletions
diff --git a/libstdc++-v3/include/bits/regex_error.h b/libstdc++-v3/include/bits/regex_error.h index b40351a39cc..f2899174352 100644 --- a/libstdc++-v3/include/bits/regex_error.h +++ b/libstdc++-v3/include/bits/regex_error.h @@ -61,6 +61,7 @@ namespace regex_constants _S_error_badrepeat, _S_error_complexity, _S_error_stack, + _S_null }; /** The expression contained an invalid collating element name. */ diff --git a/libstdc++-v3/include/bits/regex_scanner.tcc b/libstdc++-v3/include/bits/regex_scanner.tcc index cb8a526ea1a..a5a16af6cec 100644 --- a/libstdc++-v3/include/bits/regex_scanner.tcc +++ b/libstdc++-v3/include/bits/regex_scanner.tcc @@ -176,6 +176,16 @@ namespace __detail _M_state = _S_state_in_brace; _M_token = _S_token_interval_begin; } + else if (__builtin_expect(__c == _CharT(0), false)) + { + if (!_M_is_ecma()) + { + __throw_regex_error(regex_constants::_S_null, + "Unexpected null character in regular expression"); + } + _M_token = _S_token_ord_char; + _M_value.assign(1, __c); + } else if (__c != ']' && __c != '}') { auto __it = _M_token_tbl; diff --git a/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc b/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc new file mode 100644 index 00000000000..b9971dcaac5 --- /dev/null +++ b/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc @@ -0,0 +1,39 @@ +// { dg-do run { target c++11 } } +#include <regex> +#include <string> +#include <testsuite_hooks.h> + +void test01() +{ + const std::string s(1ul, '\0'); + std::regex re(s); + VERIFY( std::regex_match(s, re) ); // PR libstdc++/84110 + +#if __cpp_exceptions + using namespace std::regex_constants; + for (auto syn : {basic, extended, awk, grep, egrep}) + { + try + { + std::regex{s, syn}; // '\0' is not valid for other grammars + VERIFY( false ); + } + catch (const std::regex_error&) + { + } + } +#endif +} + +void test02() +{ + const std::string s("uh-\0h", 5); + std::regex re(s); + VERIFY( std::regex_match(s, re) ); +} + +int main() +{ + test01(); + test02(); +} |