From c6f5dd7ac8ef62dcdec4cdeda1467c658161afff Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Tue, 7 Jan 2025 15:52:07 +0100 Subject: [PATCH] qga: Don't daemonize before channel is initialized MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit If the agent is set to daemonize but for whatever reason fails to init the channel, the error message is lost. Worse, the agent daemonizes needlessly and returns success. For instance: # qemu-ga -m virtio-serial \ -p /dev/nonexistent_device \ -f /run/qemu-ga.pid \ -t /run \ -d # echo $? 0 This makes it needlessly hard for init scripts to detect a failure in qemu-ga startup. Though, they shouldn't pass '-d' in the first place. Let's open the channel first and only after that become a daemon. Related bug: https://bugs.gentoo.org/810628 Signed-off-by: Michal Privoznik Reviewed-by: Ján Tomko Reviewed-by: Konstantin Kostiuk Message-ID: <7a42b0cbda5c7e01cf76bc1b29a1210cd018fa78.1736261360.git.mprivozn@redhat.com> Signed-off-by: Konstantin Kostiuk --- qga/main.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/qga/main.c b/qga/main.c index eccfa33871..72c39b042f 100644 --- a/qga/main.c +++ b/qga/main.c @@ -1430,7 +1430,6 @@ static GAState *initialize_agent(GAConfig *config, int socket_activation) if (config->daemonize) { /* delay opening/locking of pidfile till filesystems are unfrozen */ s->deferred_options.pid_filepath = config->pid_filepath; - become_daemon(NULL); } if (config->log_filepath) { /* delay opening the log file till filesystems are unfrozen */ @@ -1438,9 +1437,6 @@ static GAState *initialize_agent(GAConfig *config, int socket_activation) } ga_disable_logging(s); } else { - if (config->daemonize) { - become_daemon(config->pid_filepath); - } if (config->log_filepath) { FILE *log_file = ga_open_logfile(config->log_filepath); if (!log_file) { @@ -1487,6 +1483,20 @@ static GAState *initialize_agent(GAConfig *config, int socket_activation) ga_apply_command_filters(s); + if (!channel_init(s, s->config->method, s->config->channel_path, + s->socket_activation ? FIRST_SOCKET_ACTIVATION_FD : -1)) { + g_critical("failed to initialize guest agent channel"); + return NULL; + } + + if (config->daemonize) { + if (ga_is_frozen(s)) { + become_daemon(NULL); + } else { + become_daemon(config->pid_filepath); + } + } + ga_state = s; return s; } @@ -1513,8 +1523,9 @@ static void cleanup_agent(GAState *s) static int run_agent_once(GAState *s) { - if (!channel_init(s, s->config->method, s->config->channel_path, - s->socket_activation ? FIRST_SOCKET_ACTIVATION_FD : -1)) { + if (!s->channel && + channel_init(s, s->config->method, s->config->channel_path, + s->socket_activation ? FIRST_SOCKET_ACTIVATION_FD : -1)) { g_critical("failed to initialize guest agent channel"); return EXIT_FAILURE; } @@ -1523,6 +1534,7 @@ static int run_agent_once(GAState *s) if (s->channel) { ga_channel_free(s->channel); + s->channel = NULL; } return EXIT_SUCCESS; -- 2.30.2