dict_synonym.c: remove incorrect outlen.

Previously, outlen was miscalculated if case_sensitive was false and
str_tolower() changed the byte length of the string. If outlen was too
large, pnstrdup() would stop at the NUL terminator, preventing
overrun. But if outlen was too small, it would cause truncation.

Fix by just removing outlen. It was only used in a single site, which
could just as well use pstrdup().

Discussion: https://postgre.es/m/1101e1a3afbbabb503317069c40374b82e6f4cac.camel@j-davis.com
Reviewed-by: Tristan Partin <tristan@partin.io>
Backpatch-through: 14

diff --git a/src/backend/tsearch/dict_synonym.c b/src/backend/tsearch/dict_synonym.c
index 41bbda57c461370c62f0685cba143e8ecce26bb0..b7710bc0c98b380cdf2229dbc952be12694a3f18 100644 (file)
--- a/src/backend/tsearch/dict_synonym.c
+++ b/src/backend/tsearch/dict_synonym.c
@@ -22,7 +22,6 @@ typedef struct
 {
        char       *in;
        char       *out;
-       int                     outlen;
        uint16          flags;
 } Syn;
 
@@ -187,7 +186,6 @@ dsynonym_init(PG_FUNCTION_ARGS)
                        d->syn[cur].out = lowerstr(starto);
                }
 
-               d->syn[cur].outlen = strlen(starto);
                d->syn[cur].flags = flags;
 
                cur++;
@@ -234,7 +232,7 @@ dsynonym_lexize(PG_FUNCTION_ARGS)
                PG_RETURN_POINTER(NULL);
 
        res = palloc0(sizeof(TSLexeme) * 2);
-       res[0].lexeme = pnstrdup(found->out, found->outlen);
+       res[0].lexeme = pstrdup(found->out);
        res[0].flags = found->flags;
 
        PG_RETURN_POINTER(res);