fuzz: unify logging setup

Make sure we don't log anything when running in "fuzzing" mode. Also,
when at it, unify the setup logic into a helper, pretty similar to
the test_setup_logging() one.

Addresses:
  - https://github.com/systemd/systemd/pull/29558#pullrequestreview-1676060607
  - https://github.com/systemd/systemd/pull/29558#discussion_r1358940663

src/core/fuzz-execute-serialize.c

@@ -82,12 +82,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_fdset_free_ FDSet *fdset = NULL;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone. */
-        if (!getenv("SYSTEMD_LOG_LEVEL")) {
-                log_set_max_level(LOG_CRIT);
-                log_set_target(LOG_TARGET_NULL);
-        }
+        fuzz_setup_logging();
 
         assert_se(fdset = fdset_new());
         assert_se(f = data_to_file(data, size));

src/core/fuzz-manager-serialize.c

@@ -17,12 +17,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone. */
-        if (!getenv("SYSTEMD_LOG_LEVEL")) {
-                log_set_max_level(LOG_CRIT);
-                log_set_target(LOG_TARGET_NULL);
-        }
+        fuzz_setup_logging();
 
         assert_se(manager_new(RUNTIME_SCOPE_SYSTEM, MANAGER_TEST_RUN_MINIMAL|MANAGER_TEST_DONT_OPEN_EXECUTOR, &m) >= 0);
         /* Set log overrides as well to make it harder for a serialization file

src/core/fuzz-unit-file.c

@@ -60,10 +60,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
         assert_se(fseek(f, offset, SEEK_SET) == 0);
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(manager_new(RUNTIME_SCOPE_SYSTEM, MANAGER_TEST_RUN_MINIMAL|MANAGER_TEST_DONT_OPEN_EXECUTOR, &m) >= 0);
 

src/fuzz/fuzz-bootspec.c

@@ -87,9 +87,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        /* Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(datadup = memdup_suffix0(data, size));
 

src/fuzz/fuzz-bus-label.c

@@ -9,6 +9,8 @@
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_free_ char *unescaped = NULL, *escaped = NULL;
 
+        fuzz_setup_logging();
+
         unescaped = bus_label_unescape_n((const char*)data, size);
         assert_se(unescaped != NULL);
         escaped = bus_label_escape(unescaped);

src/fuzz/fuzz-calendarspec.c

@@ -12,8 +12,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_free_ char *str = NULL;
         int r;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(str = memdup_suffix0(data, size));
 

src/fuzz/fuzz-catalog.c

@@ -11,8 +11,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_close_ int fd = -EBADF;
         _cleanup_ordered_hashmap_free_free_free_ OrderedHashmap *h = NULL;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(h = ordered_hashmap_new(&catalog_hash_ops));
 

src/fuzz/fuzz-compress.c

@@ -29,10 +29,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
         int alg = h->alg;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         log_info("Using compression %s, data size=%zu",
                  compression_to_string(alg),

src/fuzz/fuzz-env-file.c

@@ -18,10 +18,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         f = data_to_file(data, size);
         assert_se(f);
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         (void) load_env_file(f, NULL, &rl);
         assert_se(fseek(f, 0, SEEK_SET) == 0);

src/fuzz/fuzz-hostname-setup.c

@@ -12,10 +12,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         f = data_to_file(data, size);
         assert_se(f);
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         (void) read_etc_hostname_stream(f, &ret);
 

src/fuzz/fuzz-json.c

@@ -14,9 +14,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         FILE *g = NULL;
         int r;
 
-        /* Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         f = data_to_file(data, size);
         assert_se(f);

src/fuzz/fuzz-time-util.c

@@ -9,8 +9,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_free_ char *str = NULL;
         usec_t usec;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(str = memdup_suffix0(data, size));
 

src/fuzz/fuzz-udev-database.c

@@ -12,8 +12,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(unlink_tempfilep) char filename[] = "/tmp/fuzz-udev-database.XXXXXX";
         _cleanup_fclose_ FILE *f = NULL;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(fmkostemp_safe(filename, "r+", &f) == 0);
         if (size != 0)

src/fuzz/fuzz-varlink-idl.c

@@ -14,9 +14,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_free_ char *str = NULL, *dump = NULL;
         int r;
 
-        log_set_max_level(LOG_CRIT);
-        log_parse_environment();
-        (void) log_open();
+        fuzz_setup_logging();
 
         assert_se(str = memdup_suffix0(data, size));
 

src/fuzz/fuzz-varlink.c

@@ -92,8 +92,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(varlink_flush_close_unrefp) Varlink *c = NULL;
         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 
-        log_set_max_level(LOG_CRIT);
-        log_parse_environment();
+        fuzz_setup_logging();
 
         assert_se(null = fopen("/dev/null", "we"));
 

src/fuzz/fuzz.h

@@ -28,5 +28,13 @@ static inline bool outside_size_range(size_t size, size_t lower, size_t upper) {
         return false;
 }
 
+static inline void fuzz_setup_logging(void) {
+        /* We don't want to fill the logs and slow down stuff when running
+         * in a fuzzing mode, so disable most of the logging. */
+        log_set_max_level(LOG_CRIT);
+        log_parse_environment();
+        log_open();
+}
+
 /* Force value to not be optimized away. */
 #define DO_NOT_OPTIMIZE(value) ({ asm volatile("" : : "g"(value) : "memory"); })

src/journal-remote/fuzz-journal-remote.c

@@ -30,8 +30,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 3, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_ERR);
+        fuzz_setup_logging();
 
         assert_se(mkdtemp_malloc("/tmp/fuzz-journal-remote-XXXXXX", &tmp) >= 0);
         assert_se(name = path_join(tmp, "fuzz-journal-remote.XXXXXX.journal"));

src/journal/fuzz-journald-audit.c

@@ -7,6 +7,8 @@
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         Server s;
 
+        fuzz_setup_logging();
+
         dummy_server_init(&s, data, size);
         process_audit_string(&s, 0, s.buffer, size);
         server_done(&s);

src/journal/fuzz-journald-kmsg.c

@@ -10,10 +10,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (size == 0)
                 return 0;
 
-        /* We don't want to fill the logs with assert warnings.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         dummy_server_init(&s, data, size);
         dev_kmsg_record(&s, s.buffer, size);

src/journal/fuzz-journald-native-fd.c

@@ -18,8 +18,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         struct ucred ucred;
         struct timeval *tv = NULL;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         dummy_server_init(&s, NULL, 0);
 

src/journal/fuzz-journald-native.c

@@ -5,6 +5,8 @@
 #include "journald-native.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        fuzz_setup_logging();
+
         fuzz_journald_processing_function(data, size, server_process_native_message);
         return 0;
 }

src/journal/fuzz-journald-stream.c

@@ -19,8 +19,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 1, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0, stream_fds) >= 0);
         dummy_server_init(&s, NULL, 0);

src/journal/fuzz-journald-syslog.c

@@ -5,6 +5,8 @@
 #include "journald-syslog.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        fuzz_setup_logging();
+
         fuzz_journald_processing_function(data, size, server_process_syslog_message);
         return 0;
 }

src/libsystemd-network/fuzz-dhcp-client.c

@@ -56,8 +56,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
         assert_se(setenv("SYSTEMD_NETWORK_TEST_MODE", "1", 1) >= 0);
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         r = sd_dhcp_client_new(&client, false);
         assert_se(r >= 0);

src/libsystemd-network/fuzz-dhcp-server-relay.c

@@ -25,6 +25,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (size < sizeof(DHCPMessage))
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(sd_dhcp_server_new(&server, 1) >= 0);
         assert_se(sd_dhcp_server_attach_event(server, NULL, 0) >= 0);
         assert_se(sd_dhcp_server_configure_pool(server, &address, 24, 0, 0) >= 0);

src/libsystemd-network/fuzz-dhcp-server.c

@@ -78,6 +78,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (size < sizeof(DHCPMessage))
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(duped = memdup(data, size));
 
         assert_se(sd_dhcp_server_new(&server, 1) >= 0);

src/libsystemd-network/fuzz-dhcp6-client.c

@@ -75,8 +75,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
         assert_se(setenv("SYSTEMD_NETWORK_TEST_MODE", "1", 1) >= 0);
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         if (outside_size_range(size, 0, 65536))
                 return 0;

src/libsystemd-network/fuzz-lldp-rx.c

@@ -26,6 +26,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 2048))
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(sd_event_new(&e) == 0);
         assert_se(sd_lldp_rx_new(&lldp_rx) >= 0);
         assert_se(sd_lldp_rx_set_ifindex(lldp_rx, 42) >= 0);

src/libsystemd-network/fuzz-ndisc-rs.c

@@ -23,6 +23,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 2048))
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(sd_event_new(&e) >= 0);
         assert_se(sd_ndisc_new(&nd) >= 0);
         assert_se(sd_ndisc_attach_event(nd, e, 0) >= 0);

src/libsystemd/sd-bus/fuzz-bus-match.c

@@ -18,10 +18,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         r = sd_bus_new(&bus);
         assert_se(r >= 0);

src/libsystemd/sd-bus/fuzz-bus-message.c

@@ -17,10 +17,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         FILE *g = NULL;
         int r;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         r = sd_bus_new(&bus);
         assert_se(r >= 0);

src/network/fuzz-netdev-parser.c

@@ -14,8 +14,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(fmkostemp_safe(netdev_config, "r+", &f) == 0);
         if (size != 0)

src/network/fuzz-network-parser.c

@@ -14,8 +14,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(fmkostemp_safe(network_config, "r+", &f) == 0);
         if (size != 0)

src/nspawn/fuzz-nspawn-oci.c

@@ -15,10 +15,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         f = data_to_file(data, size);
         assert_se(f);
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         (void) oci_load(f, "/dev/null", &s);
 

src/nspawn/fuzz-nspawn-settings.c

@@ -15,10 +15,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         f = data_to_file(data, size);
         assert_se(f);
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         (void) settings_load(f, "/dev/null", &s);
 

src/resolve/fuzz-dns-packet.c

@@ -10,6 +10,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, DNS_PACKET_SIZE_MAX))
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(dns_packet_new(&p, DNS_PROTOCOL_DNS, 0, DNS_PACKET_SIZE_MAX) >= 0);
         p->size = 0; /* by default append starts after the header, undo that */
         assert_se(dns_packet_append_blob(p, data, size, NULL) >= 0);

src/resolve/fuzz-etc-hosts.c

@@ -8,8 +8,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(etc_hosts_clear) EtcHosts h = {};
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         f = data_to_file(data, size);
         assert_se(f);

src/resolve/fuzz-resource-record.c

@@ -18,6 +18,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (dns_resource_record_new_from_raw(&rr, data, size) < 0)
                 return 0;
 
+        fuzz_setup_logging();
+
         assert_se(copy = dns_resource_record_copy(rr));
         assert_se(dns_resource_record_equal(copy, rr) > 0);
 

src/systemctl/fuzz-systemctl-parse-argv.c

@@ -22,10 +22,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (size > 16*1024)
                 return 0; /* See the comment below about the limit for strv_length(). */
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         arg_pager_flags = PAGER_DISABLE; /* We shouldn't execute the pager */
 

src/udev/fido_id/fuzz-fido-id-desc.c

@@ -10,10 +10,7 @@
 #include "log.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         if (outside_size_range(size, 0, HID_MAX_DESCRIPTOR_SIZE))
                 return 0;

src/udev/fuzz-udev-rules.c

@@ -18,8 +18,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(fmkostemp_safe(filename, "r+", &f) == 0);
         if (size != 0)

src/udev/net/fuzz-link-parser.c

@@ -14,8 +14,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(fmkostemp_safe(filename, "r+", &f) == 0);
         if (size != 0)

src/xdg-autostart-generator/fuzz-xdg-desktop.c

@@ -20,10 +20,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (outside_size_range(size, 0, 65536))
                 return 0;
 
-        /* We don't want to fill the logs with messages about parse errors.
-         * Disable most logging if not running standalone */
-        if (!getenv("SYSTEMD_LOG_LEVEL"))
-                log_set_max_level(LOG_CRIT);
+        fuzz_setup_logging();
 
         assert_se(mkdtemp_malloc("/tmp/fuzz-xdg-desktop-XXXXXX", &tmpdir) >= 0);