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| author | Karl Williamson <khw@cpan.org> | 2017-02-13 19:01:46 -0700 |
|---|---|---|
| committer | Karl Williamson <khw@cpan.org> | 2017-02-13 21:24:10 -0700 |
| commit | f065e1e68bf6a5541c8ceba8c9fcc6e18f51a32b (patch) | |
| tree | e5eb48b118b39cae84c6d853ed0ff80c584de72c | |
| parent | d43328d502ac91c4d98e218d0721cd5f3bcd3950 (diff) | |
| download | perl-f065e1e68bf6a5541c8ceba8c9fcc6e18f51a32b.tar.gz | |
Don't try to compile a pattern known to be in error
Regular expression patterns are parsed by the lexer/toker, and then
compiled by the regex compiler. It is foolish to try to compile one
that the parser has rejected as syntactically bad; assumptions may be
violated and segfaults ensue. This commit abandons all parsing
immediately if a pattern had errors in it. A better solution would be
to flag this pattern as not to be compiled, and continue parsing other
things so as to find the most errors in a single attempt, but I don't
think it's worth the extra effort.
Making this change caused some misleading error messages in the test
suite to be replaced by better ones.
| -rw-r--r-- | t/re/re_tests | 7 | ||||
| -rw-r--r-- | toke.c | 9 |
2 files changed, 11 insertions, 5 deletions
diff --git a/t/re/re_tests b/t/re/re_tests index f210202657..410fceadac 100644 --- a/t/re/re_tests +++ b/t/re/re_tests @@ -1464,13 +1464,10 @@ abc\N abc\n n # Verify get errors. For these, we need // or else puts it in single quotes, # and bypasses the lexer. /\N{U+}/ - c - Invalid hexadecimal number -# Below currently gives a misleading message -/[\N{U+}]/ - Sc - Unmatched -/[\N{U+}]/ - sc - Syntax error in (?[...]) +/[\N{U+}]/ - c - Invalid hexadecimal number /abc\N{def/ - c - Missing right brace /\N{U+4AG3}/ - c - Invalid hexadecimal number -/[\N{U+4AG3}]/ - Sc - Unmatched -/[\N{U+4AG3}]/ - sc - Syntax error in (?[...]) +/[\N{U+4AG3}]/ - c - Invalid hexadecimal number # And verify that in single quotes which bypasses the lexer, the regex compiler # figures it out. @@ -5021,7 +5021,16 @@ Perl_yylex(pTHX) s = PL_bufend; } else { + int save_error_count = PL_error_count; + s = scan_const(PL_bufptr); + + /* Quit if this was a pattern and there were errors. This prevents + * us from trying to regex compile a broken pattern, which could + * lead to segfaults, etc. */ + if (PL_lex_inpat && PL_error_count > save_error_count) { + yyquit(); + } if (*s == '\\') PL_lex_state = LEX_INTERPCASEMOD; else |