Fix: race between lttng-ust getenv() and application setenv()

[lttng-ust.git] / liblttng-ust / lttng-ust-comm.c

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index 34b930d284f891c96be11a87f1fd2ff4c924c307..61d5d2d87ad14df1cbd96fe813c6b782d680f9fe 100644 (file)
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -356,11 +356,11 @@ const char *get_lttng_home_dir(void)
 {
        const char *val;
 
-       val = (const char *) lttng_secure_getenv("LTTNG_HOME");
+       val = (const char *) lttng_getenv("LTTNG_HOME");
        if (val != NULL) {
                return val;
        }
-       return (const char *) lttng_secure_getenv("HOME");
+       return (const char *) lttng_getenv("HOME");
 }
 
 /*
@@ -460,7 +460,7 @@ long get_timeout(void)
        long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS;
 
        if (!got_timeout_env) {
-               str_timeout = getenv("LTTNG_UST_REGISTER_TIMEOUT");
+               str_timeout = lttng_getenv("LTTNG_UST_REGISTER_TIMEOUT");
                got_timeout_env = 1;
        }
        if (str_timeout)
@@ -946,6 +946,21 @@ int handle_message(struct sock_info *sock_info,
                }
        }
        DBG("Return value: %d", lur.ret_val);
+
+       ust_unlock();
+
+       /*
+        * Performed delayed statedump operations outside of the UST
+        * lock. We need to take the dynamic loader lock before we take
+        * the UST lock internally within handle_pending_statedump().
+         */
+       handle_pending_statedump(sock_info);
+
+       if (ust_lock()) {
+               ret = -LTTNG_UST_ERR_EXITING;
+               goto error;
+       }
+
        ret = send_reply(sock, &lur);
        if (ret < 0) {
                DBG("error sending reply");
@@ -976,13 +991,6 @@ int handle_message(struct sock_info *sock_info,
 error:
        ust_unlock();
 
-       /*
-        * Performed delayed statedump operations outside of the UST
-        * lock. We need to take the dynamic loader lock before we take
-        * the UST lock internally within handle_pending_statedump().
-         */
-       handle_pending_statedump(sock_info);
-
        return ret;
 }
 
@@ -1589,6 +1597,7 @@ void __attribute__((constructor)) lttng_ust_init(void)
         * sessiond before the init functions are completed).
         */
        init_usterr();
+       lttng_ust_getenv_init();        /* Needs init_usterr() to be completed. */
        init_tracepoint();
        lttng_ust_clock_init();
        lttng_ust_getcpu_init();