diff options
author | James Westman <james@flyingpimonster.net> | 2020-11-16 22:56:08 -0600 |
---|---|---|
committer | James Westman <james@flyingpimonster.net> | 2020-11-30 17:14:00 -0600 |
commit | 7711cbc7f8d85d909bd4ccaa0c4c0f8d306f872f (patch) | |
tree | b16113f9c4d068de9cd0aebfbdf31ba57807258a | |
parent | f4eeb6624eb4269f95067a83f78c4590cf2de9fb (diff) | |
download | json-glib-7711cbc7f8d85d909bd4ccaa0c4c0f8d306f872f.tar.gz |
scanner: Fix crash on malformed surrogate pairs
JSON-GLib would crash when trying to decode escaped Unicode characters, if
a character of a surrogate pair was detected but it was in the wrong range, or
if the following character was not in the correct range.
Fixed by emitting an error ("Parse error: scanner: malformed surrogate pair")
before the assertion is run.
Fixes #26.
-rw-r--r-- | json-glib/json-scanner.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/json-glib/json-scanner.c b/json-glib/json-scanner.c index 59dd29c..e9a58be 100644 --- a/json-glib/json-scanner.c +++ b/json-glib/json-scanner.c @@ -40,6 +40,10 @@ #include <io.h> /* For _read() */ #endif +enum { + JSON_ERR_MALFORMED_SURROGATE_PAIR = G_TOKEN_LAST + 1, +}; + struct _JsonScannerConfig { /* Character sets @@ -681,7 +685,11 @@ json_scanner_unexp_token (JsonScanner *scanner, case G_ERR_DIGIT_RADIX: g_snprintf (token_string, token_string_len, "scanner: digit is beyond radix"); break; - + + case JSON_ERR_MALFORMED_SURROGATE_PAIR: + g_snprintf (token_string, token_string_len, "scanner: malformed surrogate pair"); + break; + case G_ERR_UNKNOWN: default: g_snprintf (token_string, token_string_len, "scanner: unknown error"); @@ -1066,7 +1074,7 @@ json_scanner_get_token_ll (JsonScanner *scanner, gstring = g_string_new (NULL); while ((ch = json_scanner_get_char (scanner, line_p, position_p)) != 0) { - if (ch == '"') + if (ch == '"' || token == G_TOKEN_ERROR) { in_string_dq = FALSE; break; @@ -1130,8 +1138,20 @@ json_scanner_get_token_ll (JsonScanner *scanner, units[0] = ucs; units[1] = json_scanner_get_unichar (scanner, line_p, position_p); - ucs = decode_utf16_surrogate_pair (units); - g_assert (g_unichar_validate (ucs)); + if (0xdc00 <= units[1] && units[1] <= 0xdfff && + 0xd800 <= units[0] && units[0] <= 0xdbff) + { + ucs = decode_utf16_surrogate_pair (units); + g_assert (g_unichar_validate (ucs)); + } + else + { + token = G_TOKEN_ERROR; + value.v_error = JSON_ERR_MALFORMED_SURROGATE_PAIR; + gstring = NULL; + break; + } + } } |