Fix string truncation to be multibyte-aware in text_name and bpchar_name.

Previously, casts to name could generate invalidly-encoded results.

Also, make these functions match namein() more exactly, by consistently
using palloc0() instead of ad-hoc zeroing code.

Back-patch to all supported branches.

Karl Schnaitter and Tom Lane

diff --git a/src/backend/utils/adt/name.c b/src/backend/utils/adt/name.c
index 736e26ddb429f3da08b8e5432f4753189c09552b..b3273b89427cc17ecc4632fbdad64553582170ca 100644 (file)
--- a/src/backend/utils/adt/name.c
+++ b/src/backend/utils/adt/name.c
@@ -46,13 +46,17 @@ Datum
 namein(PG_FUNCTION_ARGS)
 {
        char       *s = PG_GETARG_CSTRING(0);
-       NameData   *result;
+       Name            result;
        int                     len;
 
        len = strlen(s);
-       len = pg_mbcliplen(s, len, NAMEDATALEN - 1);
 
-       result = (NameData *) palloc0(NAMEDATALEN);
+       /* Truncate oversize input */
+       if (len >= NAMEDATALEN)
+               len = pg_mbcliplen(s, len, NAMEDATALEN - 1);
+
+       /* We use palloc0 here to ensure result is zero-padded */
+       result = (Name) palloc0(NAMEDATALEN);
        memcpy(NameStr(*result), s, len);
 
        PG_RETURN_NAME(result);

diff --git a/src/backend/utils/adt/varchar.c b/src/backend/utils/adt/varchar.c
index dd3fdea7a4e887e22f6324b3208ba352fcf2fee4..05b2753890887240d520c6f26b24be59bb729bcb 100644 (file)
--- a/src/backend/utils/adt/varchar.c
+++ b/src/backend/utils/adt/varchar.c
@@ -371,9 +371,9 @@ bpchar_name(PG_FUNCTION_ARGS)
        len = VARSIZE_ANY_EXHDR(s);
        s_data = VARDATA_ANY(s);
 
-       /* Truncate to max length for a Name */
+       /* Truncate oversize input */
        if (len >= NAMEDATALEN)
-               len = NAMEDATALEN - 1;
+               len = pg_mbcliplen(s_data, len, NAMEDATALEN - 1);
 
        /* Remove trailing blanks */
        while (len > 0)
@@ -383,16 +383,10 @@ bpchar_name(PG_FUNCTION_ARGS)
                len--;
        }
 
-       result = (NameData *) palloc(NAMEDATALEN);
+       /* We use palloc0 here to ensure result is zero-padded */
+       result = (Name) palloc0(NAMEDATALEN);
        memcpy(NameStr(*result), s_data, len);
 
-       /* Now null pad to full length... */
-       while (len < NAMEDATALEN)
-       {
-               *(NameStr(*result) + len) = '\0';
-               len++;
-       }
-
        PG_RETURN_NAME(result);
 }
 

diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index ccef8ae1bed79639f47c22eed86c9cb506884aca..7d97d61ff26521328346191c2ce4a1b0d5b512e0 100644 (file)
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -2145,18 +2145,12 @@ text_name(PG_FUNCTION_ARGS)
 
        /* Truncate oversize input */
        if (len >= NAMEDATALEN)
-               len = NAMEDATALEN - 1;
+               len = pg_mbcliplen(VARDATA_ANY(s), len, NAMEDATALEN - 1);
 
-       result = (Name) palloc(NAMEDATALEN);
+       /* We use palloc0 here to ensure result is zero-padded */
+       result = (Name) palloc0(NAMEDATALEN);
        memcpy(NameStr(*result), VARDATA_ANY(s), len);
 
-       /* now null pad to full length... */
-       while (len < NAMEDATALEN)
-       {
-               *(NameStr(*result) + len) = '\0';
-               len++;
-       }
-
        PG_RETURN_NAME(result);
 }