From: Tom Lane Date: Mon, 2 Feb 2004 03:07:14 +0000 (+0000) Subject: Avoid generating invalid character encoding sequences in make_greater_string. X-Git-Tag: REL7_4_2~47 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=a8fcb748e35248c82fe15991958ed9e5e3b8c8dd;p=postgresql Avoid generating invalid character encoding sequences in make_greater_string. Not sure how this mistake evaded detection for so long. --- diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index dbe930618b..77986d4ca8 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -15,7 +15,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.147.2.1 2003/12/07 04:12:50 joe Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.147.2.2 2004/02/02 03:07:14 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -3738,6 +3738,11 @@ pattern_selectivity(Const *patt, Pattern_Type ptype) * * This could be rather slow in the worst case, but in most cases we * won't have to try more than one or two strings before succeeding. + * + * NOTE: at present this assumes we are in the C locale, so that simple + * bytewise comparison applies. However, we might be in a multibyte + * encoding such as UTF-8, so we do have to watch out for generating + * invalid encoding sequences. */ Const * make_greater_string(const Const *str_const) @@ -3784,13 +3789,20 @@ make_greater_string(const Const *str_const) /* * Try to generate a larger string by incrementing the last byte. */ - if (*lastchar < (unsigned char) 255) + while (*lastchar < (unsigned char) 255) { Const *workstr_const; (*lastchar)++; + if (datatype != BYTEAOID) + { + /* do not generate invalid encoding sequences */ + if (!pg_verifymbstr((const unsigned char *) workstr, + len, true)) + continue; workstr_const = string_to_const(workstr, datatype); + } else workstr_const = string_to_bytea_const(workstr, len);