Fix bad cleanup of context structure

[lttng-tools.git] / ltt-sessiond / main.c

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index 5e99c7987ce59cb7122e6109d198e35d8399b196..73f80599c06b3491acedb298fd7e1d37d4cd569c 100644 (file)
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -226,18 +226,18 @@ static int send_unix_sock(int sock, void *buf, size_t len)
  *
  *  Free memory of a command context structure.
  */
-static void clean_command_ctx(struct command_ctx *cmd_ctx)
+static void clean_command_ctx(struct command_ctx **cmd_ctx)
 {
-       DBG("Clean command context structure %p", cmd_ctx);
-       if (cmd_ctx) {
-               if (cmd_ctx->llm) {
-                       free(cmd_ctx->llm);
+       DBG("Clean command context structure");
+       if (*cmd_ctx) {
+               if ((*cmd_ctx)->llm) {
+                       free((*cmd_ctx)->llm);
                }
-               if (cmd_ctx->lsm) {
-                       free(cmd_ctx->lsm);
+               if ((*cmd_ctx)->lsm) {
+                       free((*cmd_ctx)->lsm);
                }
-               free(cmd_ctx);
-               cmd_ctx = NULL;
+               free(*cmd_ctx);
+               *cmd_ctx = NULL;
        }
 }
 
@@ -2081,7 +2081,7 @@ static void *thread_manage_clients(void *data)
                        /* TODO: Inform client somehow of the fatal error. At this point,
                         * ret < 0 means that a malloc failed (ENOMEM). */
                        /* Error detected but still accept command */
-                       clean_command_ctx(cmd_ctx);
+                       clean_command_ctx(&cmd_ctx);
                        continue;
                }
 
@@ -2092,7 +2092,7 @@ static void *thread_manage_clients(void *data)
                        ERR("Failed to send data back to client");
                }
 
-               clean_command_ctx(cmd_ctx);
+               clean_command_ctx(&cmd_ctx);
 
                /* End of transmission */
                close(sock);
@@ -2109,7 +2109,7 @@ error:
 
        unlink(client_unix_sock_path);
 
-       clean_command_ctx(cmd_ctx);
+       clean_command_ctx(&cmd_ctx);
        return NULL;
 }
 
@@ -2495,6 +2495,7 @@ static void set_ulimit(void)
        int ret;
        struct rlimit lim;
 
+       /* The kernel does not allowed an infinite limit for open files */
        lim.rlim_cur = 65535;
        lim.rlim_max = 65535;
 
@@ -2515,14 +2516,13 @@ int main(int argc, char **argv)
 
        /* Create thread quit pipe */
        if (init_thread_quit_pipe() < 0) {
-               /* No goto error because nothing is initialized at this point */
-               exit(EXIT_FAILURE);
+               goto exit;
        }
 
        /* Parse arguments */
        progname = argv[0];
        if ((ret = parse_args(argc, argv) < 0)) {
-               goto error;
+               goto exit;
        }
 
        /* Daemonize */
@@ -2530,7 +2530,7 @@ int main(int argc, char **argv)
                ret = daemon(0, 0);
                if (ret < 0) {
                        perror("daemon");
-                       goto error;
+                       goto exit;
                }
        }
 
@@ -2540,7 +2540,7 @@ int main(int argc, char **argv)
        if (is_root) {
                ret = create_lttng_rundir();
                if (ret < 0) {
-                       goto error;
+                       goto exit;
                }
 
                if (strlen(apps_unix_sock_path) == 0) {
@@ -2552,23 +2552,12 @@ int main(int argc, char **argv)
                        snprintf(client_unix_sock_path, PATH_MAX,
                                        DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
                }
-
-               ret = set_kconsumerd_sockets();
-               if (ret < 0) {
-                       goto error;
-               }
-
-               /* Setup kernel tracer */
-               init_kernel_tracer();
-
-               /* Set ulimit for open files */
-               set_ulimit();
        } else {
                home_path = get_home_dir();
                if (home_path == NULL) {
                        /* TODO: Add --socket PATH option */
                        ERR("Can't get HOME directory for sockets creation.");
-                       goto error;
+                       goto exit;
                }
 
                if (strlen(apps_unix_sock_path) == 0) {
@@ -2594,10 +2583,31 @@ int main(int argc, char **argv)
        if ((ret = check_existing_daemon()) == 0) {
                ERR("Already running daemon.\n");
                /*
-                * We do not goto error because we must not
-                * cleanup() because a daemon is already running.
+                * We do not goto error because we must not cleanup() because a daemon
+                * is already running.
                 */
-               exit(EXIT_FAILURE);
+               goto exit;
+       }
+
+       /* After this point, we can safely call cleanup() so goto error is used */
+
+       /*
+        * These actions must be executed as root. We do that *after* setting up
+        * the sockets path because we MUST make the check for another daemon using
+        * those paths *before* trying to set the kernel consumer sockets and init
+        * kernel tracer.
+        */
+       if (is_root) {
+               ret = set_kconsumerd_sockets();
+               if (ret < 0) {
+                       goto error;
+               }
+
+               /* Setup kernel tracer */
+               init_kernel_tracer();
+
+               /* Set ulimit for open files */
+               set_ulimit();
        }
 
        if (set_signal_handler() < 0) {
@@ -2664,5 +2674,7 @@ int main(int argc, char **argv)
 
 error:
        cleanup();
+
+exit:
        exit(EXIT_FAILURE);
 }