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-rw-r--r--src/core/dbus-manager.c3
-rw-r--r--src/core/dbus-socket.c2
-rw-r--r--src/core/dbus-unit.c3
-rw-r--r--src/core/load-fragment-gperf.gperf.m45
-rw-r--r--src/core/main.c4
-rw-r--r--src/core/service.c34
-rw-r--r--src/core/service.h1
-rw-r--r--src/core/socket.c81
-rw-r--r--src/core/socket.h3
-rw-r--r--src/core/system.conf2
-rw-r--r--src/core/unit.c14
-rw-r--r--src/core/user.conf2
12 files changed, 91 insertions, 63 deletions
diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c
index 73c50766d1..d45f511489 100644
--- a/src/core/dbus-manager.c
+++ b/src/core/dbus-manager.c
@@ -2050,7 +2050,8 @@ const sd_bus_vtable bus_manager_vtable[] = {
SD_BUS_PROPERTY("DefaultTimeoutStartUSec", "t", bus_property_get_usec, offsetof(Manager, default_timeout_start_usec), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("DefaultTimeoutStopUSec", "t", bus_property_get_usec, offsetof(Manager, default_timeout_stop_usec), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("DefaultRestartUSec", "t", bus_property_get_usec, offsetof(Manager, default_restart_usec), SD_BUS_VTABLE_PROPERTY_CONST),
- SD_BUS_PROPERTY("DefaultStartLimitInterval", "t", bus_property_get_usec, offsetof(Manager, default_start_limit_interval), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("DefaultStartLimitIntervalSec", "t", bus_property_get_usec, offsetof(Manager, default_start_limit_interval), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("DefaultStartLimitInterval", "t", bus_property_get_usec, offsetof(Manager, default_start_limit_interval), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN), /* obsolete alias name */
SD_BUS_PROPERTY("DefaultStartLimitBurst", "u", bus_property_get_unsigned, offsetof(Manager, default_start_limit_burst), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("DefaultCPUAccounting", "b", bus_property_get_bool, offsetof(Manager, default_cpu_accounting), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("DefaultBlockIOAccounting", "b", bus_property_get_bool, offsetof(Manager, default_blockio_accounting), SD_BUS_VTABLE_PROPERTY_CONST),
diff --git a/src/core/dbus-socket.c b/src/core/dbus-socket.c
index d33e494f6b..bb09a515f8 100644
--- a/src/core/dbus-socket.c
+++ b/src/core/dbus-socket.c
@@ -149,6 +149,8 @@ const sd_bus_vtable bus_socket_vtable[] = {
SD_BUS_PROPERTY("NAccepted", "u", bus_property_get_unsigned, offsetof(Socket, n_accepted), 0),
SD_BUS_PROPERTY("FileDescriptorName", "s", property_get_fdname, 0, 0),
SD_BUS_PROPERTY("SocketProtocol", "i", bus_property_get_int, offsetof(Socket, socket_protocol), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("TriggerLimitIntervalSec", "t", bus_property_get_usec, offsetof(Socket, trigger_limit.interval), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("TriggerLimitBurst", "u", bus_property_get_unsigned, offsetof(Socket, trigger_limit.burst), SD_BUS_VTABLE_PROPERTY_CONST),
BUS_EXEC_COMMAND_LIST_VTABLE("ExecStartPre", offsetof(Socket, exec_command[SOCKET_EXEC_START_PRE]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
BUS_EXEC_COMMAND_LIST_VTABLE("ExecStartPost", offsetof(Socket, exec_command[SOCKET_EXEC_START_POST]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
BUS_EXEC_COMMAND_LIST_VTABLE("ExecStopPre", offsetof(Socket, exec_command[SOCKET_EXEC_STOP_PRE]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index abe30413c3..e912fe2192 100644
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -704,7 +704,8 @@ const sd_bus_vtable bus_unit_vtable[] = {
SD_BUS_PROPERTY("Asserts", "a(sbbsi)", property_get_conditions, offsetof(Unit, asserts), 0),
SD_BUS_PROPERTY("LoadError", "(ss)", property_get_load_error, 0, SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("Transient", "b", bus_property_get_bool, offsetof(Unit, transient), SD_BUS_VTABLE_PROPERTY_CONST),
- SD_BUS_PROPERTY("StartLimitInterval", "t", bus_property_get_usec, offsetof(Unit, start_limit.interval), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("StartLimitIntervalSec", "t", bus_property_get_usec, offsetof(Unit, start_limit.interval), SD_BUS_VTABLE_PROPERTY_CONST),
+ SD_BUS_PROPERTY("StartLimitInterval", "t", bus_property_get_usec, offsetof(Unit, start_limit.interval), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN), /* obsolete alias name */
SD_BUS_PROPERTY("StartLimitBurst", "u", bus_property_get_unsigned, offsetof(Unit, start_limit.burst), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("StartLimitAction", "s", property_get_failure_action, offsetof(Unit, start_limit_action), SD_BUS_VTABLE_PROPERTY_CONST),
SD_BUS_PROPERTY("RebootArgument", "s", NULL, offsetof(Unit, reboot_arg), SD_BUS_VTABLE_PROPERTY_CONST),
diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4
index 5568b4696f..928b913c7b 100644
--- a/src/core/load-fragment-gperf.gperf.m4
+++ b/src/core/load-fragment-gperf.gperf.m4
@@ -164,6 +164,8 @@ Unit.IgnoreOnSnapshot, config_parse_warn_compat, DISABLED_LE
Unit.JobTimeoutSec, config_parse_sec_fix_0, 0, offsetof(Unit, job_timeout)
Unit.JobTimeoutAction, config_parse_failure_action, 0, offsetof(Unit, job_timeout_action)
Unit.JobTimeoutRebootArgument, config_parse_string, 0, offsetof(Unit, job_timeout_reboot_arg)
+Unit.StartLimitIntervalSec, config_parse_sec, 0, offsetof(Unit, start_limit.interval)
+m4_dnl The following is a legacy alias name for compatibility
Unit.StartLimitInterval, config_parse_sec, 0, offsetof(Unit, start_limit.interval)
Unit.StartLimitBurst, config_parse_unsigned, 0, offsetof(Unit, start_limit.burst)
Unit.StartLimitAction, config_parse_failure_action, 0, offsetof(Unit, start_limit_action)
@@ -220,6 +222,7 @@ Service.TimeoutStartSec, config_parse_service_timeout, 0,
Service.TimeoutStopSec, config_parse_service_timeout, 0, 0
Service.RuntimeMaxSec, config_parse_sec, 0, offsetof(Service, runtime_max_usec)
Service.WatchdogSec, config_parse_sec, 0, offsetof(Service, watchdog_usec)
+m4_dnl The following three only exist for compatibility, they moved into Unit, see above
Service.StartLimitInterval, config_parse_sec, 0, offsetof(Unit, start_limit.interval)
Service.StartLimitBurst, config_parse_unsigned, 0, offsetof(Unit, start_limit.burst)
Service.StartLimitAction, config_parse_failure_action, 0, offsetof(Unit, start_limit_action)
@@ -297,6 +300,8 @@ Socket.RemoveOnStop, config_parse_bool, 0,
Socket.Symlinks, config_parse_unit_path_strv_printf, 0, offsetof(Socket, symlinks)
Socket.FileDescriptorName, config_parse_fdname, 0, 0
Socket.Service, config_parse_socket_service, 0, 0
+Socket.TriggerLimitIntervalSec, config_parse_sec, 0, offsetof(Socket, trigger_limit.interval)
+Socket.TriggerLimitBurst, config_parse_unsigned, 0, offsetof(Socket, trigger_limit.burst)
m4_ifdef(`HAVE_SMACK',
`Socket.SmackLabel, config_parse_string, 0, offsetof(Socket, smack)
Socket.SmackLabelIPIn, config_parse_string, 0, offsetof(Socket, smack_ip_in)
diff --git a/src/core/main.c b/src/core/main.c
index 75c5ff81f2..ed4d42c8cc 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -289,6 +289,7 @@ static int parse_crash_chvt(const char *value) {
}
static int set_machine_id(const char *m) {
+ assert(m);
if (sd_id128_from_string(m, &arg_machine_id) < 0)
return -EINVAL;
@@ -669,7 +670,8 @@ static int parse_config_file(void) {
{ "Manager", "DefaultTimeoutStartSec", config_parse_sec, 0, &arg_default_timeout_start_usec },
{ "Manager", "DefaultTimeoutStopSec", config_parse_sec, 0, &arg_default_timeout_stop_usec },
{ "Manager", "DefaultRestartSec", config_parse_sec, 0, &arg_default_restart_usec },
- { "Manager", "DefaultStartLimitInterval", config_parse_sec, 0, &arg_default_start_limit_interval },
+ { "Manager", "DefaultStartLimitInterval", config_parse_sec, 0, &arg_default_start_limit_interval }, /* obsolete alias */
+ { "Manager", "DefaultStartLimitIntervalSec",config_parse_sec, 0, &arg_default_start_limit_interval },
{ "Manager", "DefaultStartLimitBurst", config_parse_unsigned, 0, &arg_default_start_limit_burst },
{ "Manager", "DefaultEnvironment", config_parse_environ, 0, &arg_default_environment },
{ "Manager", "DefaultLimitCPU", config_parse_limit, RLIMIT_CPU, arg_default_rlimit },
diff --git a/src/core/service.c b/src/core/service.c
index b46dd8bcdd..f7a3fcf2b9 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -180,20 +180,17 @@ static int service_set_main_pid(Service *s, pid_t pid) {
return 0;
}
-static void service_close_socket_fd(Service *s) {
+void service_close_socket_fd(Service *s) {
assert(s);
- s->socket_fd = asynchronous_close(s->socket_fd);
-}
-
-static void service_connection_unref(Service *s) {
- assert(s);
+ /* Undo the effect of service_set_socket_fd(). */
- if (!UNIT_ISSET(s->accept_socket))
- return;
+ s->socket_fd = asynchronous_close(s->socket_fd);
- socket_connection_unref(SOCKET(UNIT_DEREF(s->accept_socket)));
- unit_ref_unset(&s->accept_socket);
+ if (UNIT_ISSET(s->accept_socket)) {
+ socket_connection_unref(SOCKET(UNIT_DEREF(s->accept_socket)));
+ unit_ref_unset(&s->accept_socket);
+ }
}
static void service_stop_watchdog(Service *s) {
@@ -321,7 +318,6 @@ static void service_done(Unit *u) {
s->bus_name_owner = mfree(s->bus_name_owner);
service_close_socket_fd(s);
- service_connection_unref(s);
unit_ref_unset(&s->accept_socket);
@@ -910,10 +906,8 @@ static void service_set_state(Service *s, ServiceState state) {
SERVICE_RUNNING, SERVICE_RELOAD,
SERVICE_STOP, SERVICE_STOP_SIGABRT, SERVICE_STOP_SIGTERM, SERVICE_STOP_SIGKILL, SERVICE_STOP_POST,
SERVICE_FINAL_SIGTERM, SERVICE_FINAL_SIGKILL) &&
- !(state == SERVICE_DEAD && UNIT(s)->job)) {
+ !(state == SERVICE_DEAD && UNIT(s)->job))
service_close_socket_fd(s);
- service_connection_unref(s);
- }
if (!IN_SET(state, SERVICE_START_POST, SERVICE_RUNNING, SERVICE_RELOAD))
service_stop_watchdog(s);
@@ -3139,9 +3133,8 @@ int service_set_socket_fd(Service *s, int fd, Socket *sock, bool selinux_context
assert(s);
assert(fd >= 0);
- /* This is called by the socket code when instantiating a new
- * service for a stream socket and the socket needs to be
- * configured. */
+ /* This is called by the socket code when instantiating a new service for a stream socket and the socket needs
+ * to be configured. We take ownership of the passed fd on success. */
if (UNIT(s)->load_state != UNIT_LOADED)
return -EINVAL;
@@ -3169,12 +3162,15 @@ int service_set_socket_fd(Service *s, int fd, Socket *sock, bool selinux_context
return r;
}
+ r = unit_add_two_dependencies(UNIT(sock), UNIT_BEFORE, UNIT_TRIGGERS, UNIT(s), false);
+ if (r < 0)
+ return r;
+
s->socket_fd = fd;
s->socket_fd_selinux_context_net = selinux_context_net;
unit_ref_set(&s->accept_socket, UNIT(sock));
-
- return unit_add_two_dependencies(UNIT(sock), UNIT_BEFORE, UNIT_TRIGGERS, UNIT(s), false);
+ return 0;
}
static void service_reset_failed(Unit *u) {
diff --git a/src/core/service.h b/src/core/service.h
index cd9e41646e..c7f1e81bdb 100644
--- a/src/core/service.h
+++ b/src/core/service.h
@@ -198,6 +198,7 @@ struct Service {
extern const UnitVTable service_vtable;
int service_set_socket_fd(Service *s, int fd, struct Socket *socket, bool selinux_context_net);
+void service_close_socket_fd(Service *s);
const char* service_restart_to_string(ServiceRestart i) _const_;
ServiceRestart service_restart_from_string(const char *s) _pure_;
diff --git a/src/core/socket.c b/src/core/socket.c
index a9fff9c259..7eeed068bd 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -99,6 +99,8 @@ static void socket_init(Unit *u) {
s->exec_context.std_error = u->manager->default_std_error;
s->control_command_id = _SOCKET_EXEC_COMMAND_INVALID;
+
+ RATELIMIT_INIT(s->trigger_limit, 5*USEC_PER_SEC, 2500);
}
static void socket_unwatch_control_pid(Socket *s) {
@@ -227,7 +229,6 @@ int socket_instantiate_service(Socket *s) {
if (r < 0)
return r;
- u->no_gc = true;
unit_ref_set(&s->service, u);
return unit_add_two_dependencies(UNIT(s), UNIT_BEFORE, UNIT_TRIGGERS, u, false);
@@ -792,47 +793,45 @@ static void socket_close_fds(Socket *s) {
assert(s);
LIST_FOREACH(port, p, s->ports) {
+ bool was_open;
- p->event_source = sd_event_source_unref(p->event_source);
-
- if (p->fd < 0)
- continue;
+ was_open = p->fd >= 0;
+ p->event_source = sd_event_source_unref(p->event_source);
p->fd = safe_close(p->fd);
socket_cleanup_fd_list(p);
- /* One little note: we should normally not delete any
- * sockets in the file system here! After all some
- * other process we spawned might still have a
- * reference of this fd and wants to continue to use
- * it. Therefore we delete sockets in the file system
- * before we create a new one, not after we stopped
- * using one! */
+ /* One little note: we should normally not delete any sockets in the file system here! After all some
+ * other process we spawned might still have a reference of this fd and wants to continue to use
+ * it. Therefore we normally delete sockets in the file system before we create a new one, not after we
+ * stopped using one! That all said, if the user explicitly requested this, we'll delete them here
+ * anyway, but only then. */
- if (s->remove_on_stop) {
- switch (p->type) {
+ if (!was_open || !s->remove_on_stop)
+ continue;
- case SOCKET_FIFO:
- unlink(p->path);
- break;
+ switch (p->type) {
- case SOCKET_MQUEUE:
- mq_unlink(p->path);
- break;
+ case SOCKET_FIFO:
+ (void) unlink(p->path);
+ break;
- case SOCKET_SOCKET:
- socket_address_unlink(&p->address);
- break;
+ case SOCKET_MQUEUE:
+ (void) mq_unlink(p->path);
+ break;
- default:
- break;
- }
+ case SOCKET_SOCKET:
+ (void) socket_address_unlink(&p->address);
+ break;
+
+ default:
+ break;
}
}
if (s->remove_on_stop)
STRV_FOREACH(i, s->symlinks)
- unlink(*i);
+ (void) unlink(*i);
}
static void socket_apply_socket_options(Socket *s, int fd) {
@@ -1887,6 +1886,9 @@ static void socket_enter_running(Socket *s, int cfd) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
int r;
+ /* Note that this call takes possession of the connection fd passed. It either has to assign it somewhere or
+ * close it. */
+
assert(s);
/* We don't take connections anymore if we are supposed to
@@ -1896,7 +1898,7 @@ static void socket_enter_running(Socket *s, int cfd) {
log_unit_debug(UNIT(s), "Suppressing connection request since unit stop is scheduled.");
if (cfd >= 0)
- safe_close(cfd);
+ cfd = safe_close(cfd);
else {
/* Flush all sockets by closing and reopening them */
socket_close_fds(s);
@@ -1918,6 +1920,13 @@ static void socket_enter_running(Socket *s, int cfd) {
return;
}
+ if (!ratelimit_test(&s->trigger_limit)) {
+ safe_close(cfd);
+ log_unit_warning(UNIT(s), "Trigger limit hit, refusing further activation.");
+ socket_enter_stop_pre(s, SOCKET_FAILURE_TRIGGER_LIMIT_HIT);
+ return;
+ }
+
if (cfd < 0) {
Iterator i;
Unit *other;
@@ -1949,7 +1958,7 @@ static void socket_enter_running(Socket *s, int cfd) {
Service *service;
if (s->n_connections >= s->max_connections) {
- log_unit_warning(UNIT(s), "Too many incoming connections (%u)", s->n_connections);
+ log_unit_warning(UNIT(s), "Too many incoming connections (%u), refusing connection attempt.", s->n_connections);
safe_close(cfd);
return;
}
@@ -1965,6 +1974,7 @@ static void socket_enter_running(Socket *s, int cfd) {
/* ENOTCONN is legitimate if TCP RST was received.
* This connection is over, but the socket unit lives on. */
+ log_unit_debug(UNIT(s), "Got ENOTCONN on incoming socket, assuming aborted connection attempt, ignoring.");
safe_close(cfd);
return;
}
@@ -1983,22 +1993,24 @@ static void socket_enter_running(Socket *s, int cfd) {
service = SERVICE(UNIT_DEREF(s->service));
unit_ref_unset(&s->service);
- s->n_accepted++;
-
- UNIT(service)->no_gc = false;
+ s->n_accepted++;
unit_choose_id(UNIT(service), name);
r = service_set_socket_fd(service, cfd, s, s->selinux_context_from_net);
if (r < 0)
goto fail;
- cfd = -1;
+ cfd = -1; /* We passed ownership of the fd to the service now. Forget it here. */
s->n_connections++;
r = manager_add_job(UNIT(s)->manager, JOB_START, UNIT(service), JOB_REPLACE, &error, NULL);
- if (r < 0)
+ if (r < 0) {
+ /* We failed to activate the new service, but it still exists. Let's make sure the service
+ * closes and forgets the connection fd again, immediately. */
+ service_close_socket_fd(service);
goto fail;
+ }
/* Notify clients about changed counters */
unit_add_to_dbus_queue(UNIT(s));
@@ -2806,6 +2818,7 @@ static const char* const socket_result_table[_SOCKET_RESULT_MAX] = {
[SOCKET_FAILURE_EXIT_CODE] = "exit-code",
[SOCKET_FAILURE_SIGNAL] = "signal",
[SOCKET_FAILURE_CORE_DUMP] = "core-dump",
+ [SOCKET_FAILURE_TRIGGER_LIMIT_HIT] = "trigger-limit-hit",
[SOCKET_FAILURE_SERVICE_START_LIMIT_HIT] = "service-start-limit-hit"
};
diff --git a/src/core/socket.h b/src/core/socket.h
index b537b026a7..2a4b1bb674 100644
--- a/src/core/socket.h
+++ b/src/core/socket.h
@@ -52,6 +52,7 @@ typedef enum SocketResult {
SOCKET_FAILURE_EXIT_CODE,
SOCKET_FAILURE_SIGNAL,
SOCKET_FAILURE_CORE_DUMP,
+ SOCKET_FAILURE_TRIGGER_LIMIT_HIT,
SOCKET_FAILURE_SERVICE_START_LIMIT_HIT,
_SOCKET_RESULT_MAX,
_SOCKET_RESULT_INVALID = -1
@@ -156,6 +157,8 @@ struct Socket {
bool reset_cpu_usage:1;
char *fdname;
+
+ RateLimit trigger_limit;
};
/* Called from the service code when collecting fds */
diff --git a/src/core/system.conf b/src/core/system.conf
index e2ded27333..eacd7ee282 100644
--- a/src/core/system.conf
+++ b/src/core/system.conf
@@ -34,7 +34,7 @@
#DefaultTimeoutStartSec=90s
#DefaultTimeoutStopSec=90s
#DefaultRestartSec=100ms
-#DefaultStartLimitInterval=10s
+#DefaultStartLimitIntervalSec=10s
#DefaultStartLimitBurst=5
#DefaultEnvironment=
#DefaultCPUAccounting=no
diff --git a/src/core/unit.c b/src/core/unit.c
index cb79c7c6b1..81cd7ee2b8 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -1497,11 +1497,6 @@ int unit_start(Unit *u) {
if (UNIT_IS_ACTIVE_OR_RELOADING(state))
return -EALREADY;
- /* Make sure we don't enter a busy loop of some kind. */
- r = unit_start_limit_test(u);
- if (r < 0)
- return r;
-
/* Units that aren't loaded cannot be started */
if (u->load_state != UNIT_LOADED)
return -EINVAL;
@@ -1543,6 +1538,11 @@ int unit_start(Unit *u) {
if (!UNIT_VTABLE(u)->start)
return -EBADR;
+ /* Make sure we don't enter a busy loop of some kind. */
+ r = unit_start_limit_test(u);
+ if (r < 0)
+ return r;
+
/* We don't suppress calls to ->start() here when we are
* already starting, to allow this request to be used as a
* "hurry up" call, for example when the unit is in some "auto
@@ -3222,6 +3222,10 @@ void unit_ref_unset(UnitRef *ref) {
if (!ref->unit)
return;
+ /* We are about to drop a reference to the unit, make sure the garbage collection has a look at it as it might
+ * be unreferenced now. */
+ unit_add_to_gc_queue(ref->unit);
+
LIST_REMOVE(refs, ref->unit->refs, ref);
ref->unit = NULL;
}
diff --git a/src/core/user.conf b/src/core/user.conf
index 87c8164378..b427f1ef6d 100644
--- a/src/core/user.conf
+++ b/src/core/user.conf
@@ -23,7 +23,7 @@
#DefaultTimeoutStartSec=90s
#DefaultTimeoutStopSec=90s
#DefaultRestartSec=100ms
-#DefaultStartLimitInterval=10s
+#DefaultStartLimitIntervalSec=10s
#DefaultStartLimitBurst=5
#DefaultEnvironment=
#DefaultLimitCPU=
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-16 22:46:00 +0000