diff --git a/src/core/fuzz-unit-file.c b/src/core/fuzz-unit-file.c
index c12e874e2d..81cede2193 100644
--- a/src/core/fuzz-unit-file.c
+++ b/src/core/fuzz-unit-file.c
@@ -21,7 +21,11 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         const char *name;
         long offset;
 
+        if (size > 65536)
+                return 0;
+
         f = data_to_file(data, size);
+
         assert_se(f);
 
         if (read_line(f, LINE_MAX, &p) < 0)
diff --git a/src/fuzz/fuzz-bootspec.c b/src/fuzz/fuzz-bootspec.c
index fa9e3f06e0..0594a0dea5 100644
--- a/src/fuzz/fuzz-bootspec.c
+++ b/src/fuzz/fuzz-bootspec.c
@@ -84,7 +84,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(boot_config_free) BootConfig config = BOOT_CONFIG_NULL;
         int r;
 
-        if (size > 65535)
+        if (size > 65536)
                 return 0;
 
         /* Disable most logging if not running standalone */
diff --git a/src/fuzz/fuzz-bootspec.options b/src/fuzz/fuzz-bootspec.options
index 0824b19fab..678d526b1e 100644
--- a/src/fuzz/fuzz-bootspec.options
+++ b/src/fuzz/fuzz-bootspec.options
@@ -1,2 +1,2 @@
 [libfuzzer]
-max_len = 65535
+max_len = 65536
diff --git a/src/fuzz/fuzz-env-file.c b/src/fuzz/fuzz-env-file.c
index 3b3e625608..431f172306 100644
--- a/src/fuzz/fuzz-env-file.c
+++ b/src/fuzz/fuzz-env-file.c
@@ -12,7 +12,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_strv_free_ char **rl = NULL, **rlp =  NULL;
 
-        if (size > 65535)
+        if (size > 65536)
                 return 0;
 
         f = data_to_file(data, size);
diff --git a/src/fuzz/fuzz-env-file.options b/src/fuzz/fuzz-env-file.options
index 0824b19fab..678d526b1e 100644
--- a/src/fuzz/fuzz-env-file.options
+++ b/src/fuzz/fuzz-env-file.options
@@ -1,2 +1,2 @@
 [libfuzzer]
-max_len = 65535
+max_len = 65536
diff --git a/src/journal-remote/fuzz-journal-remote.c b/src/journal-remote/fuzz-journal-remote.c
index a8e56e21b2..dd7884ee9a 100644
--- a/src/journal-remote/fuzz-journal-remote.c
+++ b/src/journal-remote/fuzz-journal-remote.c
@@ -24,7 +24,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(journal_remote_server_destroy) RemoteServer s = {};
         int r;
 
-        if (size <= 2)
+        if (size <= 2 || size > 65536)
                 return 0;
 
         if (!getenv("SYSTEMD_LOG_LEVEL"))
diff --git a/src/libsystemd/sd-bus/fuzz-bus-match.c b/src/libsystemd/sd-bus/fuzz-bus-match.c
index 0585338e28..39ab62196a 100644
--- a/src/libsystemd/sd-bus/fuzz-bus-match.c
+++ b/src/libsystemd/sd-bus/fuzz-bus-match.c
@@ -15,6 +15,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(sd_bus_unrefp) sd_bus *bus = NULL;
         int r;
 
+        if (size > 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"))
diff --git a/src/libsystemd/sd-bus/fuzz-bus-match.options b/src/libsystemd/sd-bus/fuzz-bus-match.options
new file mode 100644
index 0000000000..678d526b1e
--- /dev/null
+++ b/src/libsystemd/sd-bus/fuzz-bus-match.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65536
diff --git a/src/network/fuzz-netdev-parser.c b/src/network/fuzz-netdev-parser.c
index bb4b487ab2..d8cbd2891c 100644
--- a/src/network/fuzz-netdev-parser.c
+++ b/src/network/fuzz-netdev-parser.c
@@ -11,6 +11,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(unlink_tempfilep) char netdev_config[] = "/tmp/fuzz-networkd.XXXXXX";
 
+        if (size > 65536)
+                return 0;
+
         if (!getenv("SYSTEMD_LOG_LEVEL"))
                 log_set_max_level(LOG_CRIT);
 
diff --git a/src/network/fuzz-netdev-parser.options b/src/network/fuzz-netdev-parser.options
new file mode 100644
index 0000000000..678d526b1e
--- /dev/null
+++ b/src/network/fuzz-netdev-parser.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65536
diff --git a/src/network/fuzz-network-parser.c b/src/network/fuzz-network-parser.c
index 9290aa58d6..630c86a98c 100644
--- a/src/network/fuzz-network-parser.c
+++ b/src/network/fuzz-network-parser.c
@@ -11,7 +11,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(unlink_tempfilep) char network_config[] = "/tmp/fuzz-networkd.XXXXXX";
 
-        if (size > 65535)
+        if (size > 65536)
                 return 0;
 
         if (!getenv("SYSTEMD_LOG_LEVEL"))
diff --git a/src/network/fuzz-network-parser.options b/src/network/fuzz-network-parser.options
index 0824b19fab..678d526b1e 100644
--- a/src/network/fuzz-network-parser.options
+++ b/src/network/fuzz-network-parser.options
@@ -1,2 +1,2 @@
 [libfuzzer]
-max_len = 65535
+max_len = 65536
diff --git a/src/nspawn/fuzz-nspawn-oci.c b/src/nspawn/fuzz-nspawn-oci.c
index 91f2a81dfc..7110a66187 100644
--- a/src/nspawn/fuzz-nspawn-oci.c
+++ b/src/nspawn/fuzz-nspawn-oci.c
@@ -9,6 +9,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(settings_freep) Settings *s = NULL;
 
+        if (size > 65536)
+                return 0;
+
         f = data_to_file(data, size);
         assert_se(f);
 
diff --git a/src/nspawn/fuzz-nspawn-settings.c b/src/nspawn/fuzz-nspawn-settings.c
index 6b91e1506e..7683814659 100644
--- a/src/nspawn/fuzz-nspawn-settings.c
+++ b/src/nspawn/fuzz-nspawn-settings.c
@@ -9,6 +9,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(settings_freep) Settings *s = NULL;
 
+        if (size > 65536)
+                return 0;
+
         f = data_to_file(data, size);
         assert_se(f);
 
diff --git a/src/resolve/fuzz-dns-packet.options b/src/resolve/fuzz-dns-packet.options
index 0824b19fab..678d526b1e 100644
--- a/src/resolve/fuzz-dns-packet.options
+++ b/src/resolve/fuzz-dns-packet.options
@@ -1,2 +1,2 @@
 [libfuzzer]
-max_len = 65535
+max_len = 65536
diff --git a/src/udev/fuzz-udev-rules.c b/src/udev/fuzz-udev-rules.c
index 17f5ea121b..0208f8c2d8 100644
--- a/src/udev/fuzz-udev-rules.c
+++ b/src/udev/fuzz-udev-rules.c
@@ -15,6 +15,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(unlink_tempfilep) char filename[] = "/tmp/fuzz-udev-rules.XXXXXX";
         int r;
 
+        if (size > 65536)
+                return 0;
+
         if (!getenv("SYSTEMD_LOG_LEVEL"))
                 log_set_max_level(LOG_CRIT);
 
diff --git a/src/udev/net/fuzz-link-parser.c b/src/udev/net/fuzz-link-parser.c
index b871a4e23c..5727897305 100644
--- a/src/udev/net/fuzz-link-parser.c
+++ b/src/udev/net/fuzz-link-parser.c
@@ -11,7 +11,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(unlink_tempfilep) char filename[] = "/tmp/fuzz-link-config.XXXXXX";
         _cleanup_fclose_ FILE *f = NULL;
 
-        if (size > 65535)
+        if (size > 65536)
                 return 0;
 
         if (!getenv("SYSTEMD_LOG_LEVEL"))
diff --git a/src/udev/net/fuzz-link-parser.options b/src/udev/net/fuzz-link-parser.options
index 0824b19fab..678d526b1e 100644
--- a/src/udev/net/fuzz-link-parser.options
+++ b/src/udev/net/fuzz-link-parser.options
@@ -1,2 +1,2 @@
 [libfuzzer]
-max_len = 65535
+max_len = 65536
diff --git a/src/xdg-autostart-generator/fuzz-xdg-desktop.c b/src/xdg-autostart-generator/fuzz-xdg-desktop.c
index 52ba7ff0a4..0ae27fc39d 100644
--- a/src/xdg-autostart-generator/fuzz-xdg-desktop.c
+++ b/src/xdg-autostart-generator/fuzz-xdg-desktop.c
@@ -17,6 +17,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         _cleanup_(xdg_autostart_service_freep) XdgAutostartService *service = NULL;
         _cleanup_(rm_rf_physical_and_freep) char *tmpdir = NULL;
 
+        if (size > 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"))
diff --git a/src/xdg-autostart-generator/fuzz-xdg-desktop.options b/src/xdg-autostart-generator/fuzz-xdg-desktop.options
new file mode 100644
index 0000000000..678d526b1e
--- /dev/null
+++ b/src/xdg-autostart-generator/fuzz-xdg-desktop.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65536