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 fe7ca30ce97cfd78328689d87bf5f7bad05b1dd3..b1a3d955f55aa7e3f9c237ffc850e3e535df7469 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);