timedate: do not copy input string before bus_verify_polkit_async()

This fixes the commit 2c3def62144c9d689ddda88a866b1e623074eaae which
breaks `timedatectl set-timezone` called by non-privileged user.

diff --git a/src/timedate/timedated.c b/src/timedate/timedated.c
index 6928bb9..1f161d4 100644 (file)
--- a/src/timedate/timedated.c
+++ b/src/timedate/timedated.c
@@ -545,10 +545,7 @@ static int method_set_timezone(sd_bus_message *m, void *userdata, sd_bus_error *
         if (!timezone_is_valid(z, LOG_DEBUG))
                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid time zone '%s'", z);
 
-        r = free_and_strdup(&c->zone, z);
-        if (r < 0)
-                return r;
-        if (r == 0)
+        if (streq_ptr(z, c->zone))
                 return sd_bus_reply_method_return(m, NULL);
 
         r = bus_verify_polkit_async(
@@ -565,6 +562,10 @@ static int method_set_timezone(sd_bus_message *m, void *userdata, sd_bus_error *
         if (r == 0)
                 return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
 
+        r = free_and_strdup(&c->zone, z);
+        if (r < 0)
+                return r;
+
         /* 1. Write new configuration file */
         r = context_write_data_timezone(c);
         if (r < 0) {