From 0bb3185954858264aac0e25bdf0c4f14df4dbfee Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 6 Nov 2014 20:52:40 -0500 Subject: [PATCH] Cope with more than 64K phrases in a thesaurus dictionary. dict_thesaurus stored phrase IDs in uint16 fields, so it would get confused and even crash if there were more than 64K entries in the configuration file. It turns out to be basically free to widen the phrase IDs to uint32, so let's just do so. This was complained of some time ago by David Boutin (in bug #7793); he later submitted an informal patch but it was never acted on. We now have another complaint (bug #11901 from Luc Ouellette) so it's time to make something happen. This is basically Boutin's patch, but for future-proofing I also added a defense against too many words per phrase. Note that we don't need any explicit defense against overflow of the uint32 counters, since before that happens we'd hit array allocation sizes that repalloc rejects. Back-patch to all supported branches because of the crash risk. --- src/backend/tsearch/dict_thesaurus.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/src/backend/tsearch/dict_thesaurus.c b/src/backend/tsearch/dict_thesaurus.c index 7e641ef64f5..855429e9da8 100644 --- a/src/backend/tsearch/dict_thesaurus.c +++ b/src/backend/tsearch/dict_thesaurus.c @@ -28,7 +28,7 @@ typedef struct LexemeInfo { - uint16 idsubst; /* entry's number in DictThesaurus->subst */ + uint32 idsubst; /* entry's number in DictThesaurus->subst */ uint16 posinsubst; /* pos info in entry */ uint16 tnvariant; /* total num lexemes in one variant */ struct LexemeInfo *nextentry; @@ -68,7 +68,7 @@ typedef struct static void -newLexeme(DictThesaurus *d, char *b, char *e, uint16 idsubst, uint16 posinsubst) +newLexeme(DictThesaurus *d, char *b, char *e, uint32 idsubst, uint16 posinsubst) { TheLexeme *ptr; @@ -102,7 +102,7 @@ newLexeme(DictThesaurus *d, char *b, char *e, uint16 idsubst, uint16 posinsubst) } static void -addWrd(DictThesaurus *d, char *b, char *e, uint16 idsubst, uint16 nwrd, uint16 posinsubst, bool useasis) +addWrd(DictThesaurus *d, char *b, char *e, uint32 idsubst, uint16 nwrd, uint16 posinsubst, bool useasis) { static int nres = 0; static int ntres = 0; @@ -143,7 +143,6 @@ addWrd(DictThesaurus *d, char *b, char *e, uint16 idsubst, uint16 nwrd, uint16 p ntres *= 2; ptr->res = (TSLexeme *) repalloc(ptr->res, sizeof(TSLexeme) * ntres); } - } ptr->res[nres].lexeme = palloc(e - b + 1); @@ -168,7 +167,7 @@ static void thesaurusRead(char *filename, DictThesaurus *d) { tsearch_readline_state trst; - uint16 idsubst = 0; + uint32 idsubst = 0; bool useasis = false; char *line; @@ -184,8 +183,8 @@ thesaurusRead(char *filename, DictThesaurus *d) char *ptr; int state = TR_WAITLEX; char *beginwrd = NULL; - uint16 posinsubst = 0; - uint16 nwrd = 0; + uint32 posinsubst = 0; + uint32 nwrd = 0; ptr = line; @@ -286,6 +285,16 @@ thesaurusRead(char *filename, DictThesaurus *d) (errcode(ERRCODE_CONFIG_FILE_ERROR), errmsg("unexpected end of line"))); + /* + * Note: currently, tsearch_readline can't return lines exceeding 4KB, + * so overflow of the word counts is impossible. But that may not + * always be true, so let's check. + */ + if (nwrd != (uint16) nwrd || posinsubst != (uint16) posinsubst) + ereport(ERROR, + (errcode(ERRCODE_CONFIG_FILE_ERROR), + errmsg("too many lexemes in thesaurus entry"))); + pfree(line); } @@ -670,7 +679,7 @@ findTheLexeme(DictThesaurus *d, char *lexeme) } static bool -matchIdSubst(LexemeInfo *stored, uint16 idsubst) +matchIdSubst(LexemeInfo *stored, uint32 idsubst) { bool res = true;