(void) cast strlcat() and snprintf() that cannot truncate

be a bit more strict with an strlcat() truncation by causing it to fail in
table_create() instead of later in parse.y - in both cases, this would
cause smtpd to fatal() at startup if a table has a config file too large

diff --git a/usr.sbin/smtpd/table.c b/usr.sbin/smtpd/table.c
index 4b29055..a99191a 100644 (file)
--- a/usr.sbin/smtpd/table.c
+++ b/usr.sbin/smtpd/table.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: table.c,v 1.13 2013/12/26 17:25:32 eric Exp $ */
+/*     $OpenBSD: table.c,v 1.14 2014/04/19 14:19:17 gilles Exp $       */
 
 /*
  * Copyright (c) 2013 Eric Faurot <eric@openbsd.org>
@@ -213,8 +213,10 @@ table_create(const char *backend, const char *name, const char *tag,
                if (stat(path, &sb) == 0) {
                        tb = table_backend_lookup("proc");
                        if (config) {
-                               strlcat(path, " ", sizeof(path));
-                               strlcat(path, config, sizeof(path));
+                               (void)strlcat(path, " ", sizeof(path));
+                               if (strlcat(path, config, sizeof(path))
+                                   >= sizeof(path))
+                                       errx(1, "table_create: config file path too long");
                        }
                        config = path;
                }
@@ -244,7 +246,7 @@ table_create(const char *backend, const char *name, const char *tag,
                t->t_type = T_DYNAMIC;
 
        if (name == NULL)
-               snprintf(t->t_name, sizeof(t->t_name), "<dynamic:%u>",
+               (void)snprintf(t->t_name, sizeof(t->t_name), "<dynamic:%u>",
                    last_table_id++);
        else {
                n = strlcpy(t->t_name, name, sizeof(t->t_name));
@@ -483,17 +485,17 @@ table_dump_all(void)
                sep = "";
                buf[0] = '\0';
                if (t->t_type & T_DYNAMIC) {
-                       strlcat(buf, "DYNAMIC", sizeof(buf));
+                       (void)strlcat(buf, "DYNAMIC", sizeof(buf));
                        sep = ",";
                }
                if (t->t_type & T_LIST) {
-                       strlcat(buf, sep, sizeof(buf));
-                       strlcat(buf, "LIST", sizeof(buf));
+                       (void)strlcat(buf, sep, sizeof(buf));
+                       (void)strlcat(buf, "LIST", sizeof(buf));
                        sep = ",";
                }
                if (t->t_type & T_HASH) {
-                       strlcat(buf, sep, sizeof(buf));
-                       strlcat(buf, "HASH", sizeof(buf));
+                       (void)strlcat(buf, sep, sizeof(buf));
+                       (void)strlcat(buf, "HASH", sizeof(buf));
                        sep = ",";
                }
                log_debug("TABLE \"%s\" type=%s config=\"%s\"",