Fix crash when using the "matches" operator on non-UTF-8 data

GRegex is a thin wrapper around PCRE. Inputs (patterns and subjects) are
assumed to be UTF-8 by default (unless G_REGEX_RAW is set). If the
subject is not valid UTF-8, normally pcre_exec will immediately return a
failure. However, as GLib sets PCRE_NO_UTF8_CHECK when G_REGEX_RAW is
given, pcre_exec() will skip the safety check and crash instead.

Fix this by always assuming raw byte patterns. Regression risk: patterns
such as `ö.ï` will no longer match `öñï` since `ñ` is a multi-byte
sequence. Patterns such as `(GET|POST) /` remain functional though.

Bug: 14905
Change-Id: I6450bb83f565d377f82a5dbb01690c5f49acd96f
Reviewed-on: https://code.wireshark.org/review/31935
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 0 insertions, 24 deletions

diff --git a/epan/ftypes/ftype-bytes.c b/epan/ftypes/ftype-bytes.c
index c1d57f0bbd..9bfc37b637 100644
--- a/epan/ftypes/ftype-bytes.c
+++ b/epan/ftypes/ftype-bytes.c
@@ -665,30 +665,6 @@ cmp_matches(const fvalue_t *fv_a, const fvalue_t *fv_b)
 	if (! regex) {
 		return FALSE;
 	}
-	/*
-	 * XXX - do we want G_REGEX_RAW or not?
-	 *
-	 * If we're matching against a string, we don't want it (and
-	 * we want the string value encoded in UTF-8 - and, if it can't
-	 * be converted to UTF-8, because it's in a character encoding
-	 * that doesn't map every possible byte sequence to Unicode (and
-	 * that includes strings that are supposed to be in UTF-8 but
-	 * that contain invalid UTF-8 sequences!), treat the match as
-	 * failing.
-	 *
-	 * If we're matching against binary data, and matching a binary
-	 * pattern (e.g. "0xfa, 3 or more 0xff, and 0x37, in order"),
-	 * we'd want G_REGEX_RAW. If we're matching a text pattern,
-	 * it's not clear *what* the right thing to do is - if they're
-	 * matching against a pattern containing non-ASCII characters,
-	 * they might want it to match in whatever encoding the binary
-	 * data is, but Wireshark might not have a clue what that
-	 * encoding is.  In addition, it's not clear how to tell
-	 * whether a pattern is "binary" or not, short of having
-	 * a different (non-PCRE) syntax for binary patterns.
-	 *
-	 * So we don't use G_REGEX_RAW for now.
-	 */
 	return g_regex_match_full(
 		regex,			/* Compiled PCRE */
 		(char *)a->data,	/* The data to check for the pattern... */