diff --git a/src/clonesetup/clonesetup-ioctl.c b/src/clonesetup/clonesetup-ioctl.c
index 73c52e6e99..e8f7688880 100644
--- a/src/clonesetup/clonesetup-ioctl.c
+++ b/src/clonesetup/clonesetup-ioctl.c
@@ -55,6 +55,9 @@ static int dm_ioctl_run(const char *name, uint32_t cmd, struct dm_ioctl *data, s
         assert(data);
         assert(data_size >= sizeof(struct dm_ioctl));
 
+        if (data_size > UINT32_MAX)
+                return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "DM ioctl data too large.");
+
         dm->version[0] = DM_VERSION_MAJOR;
         dm->version[1] = DM_VERSION_MINOR;
         dm->version[2] = DM_VERSION_PATCHLEVEL;
@@ -98,16 +101,26 @@ static int dm_clone_create(const char *name) {
 /* Second dm ioctl needed to create a device. */
 static int dm_clone_load_table(const char *name, uint64_t size_sectors, const char *target_params) {
         char *params_buf;
-        size_t params_len, dm_size;
+        size_t params_len, target_size, dm_size;
         _cleanup_free_ struct dm_ioctl *dm = NULL;
         struct dm_target_spec *tgt;
 
         assert(name);
         assert(target_params);
 
-        params_len = strlen(target_params) + 1;
+        params_len = strlen(target_params);
+        target_size = sizeof(struct dm_target_spec);
+        if (!ADD_SAFE(&params_len, params_len, 1) ||
+            !ADD_SAFE(&target_size, target_size, params_len))
+                return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "DM target parameters too long.");
+
         /* ensure that dm_size is always aligned, so it makes the buffer actually match what .next claims */
-        dm_size = ALIGN8(sizeof(struct dm_ioctl)) + ALIGN8(sizeof(struct dm_target_spec) + params_len);
+        target_size = ALIGN8(target_size);
+        dm_size = ALIGN8(sizeof(struct dm_ioctl));
+        if (target_size == SIZE_MAX ||
+            !ADD_SAFE(&dm_size, dm_size, target_size))
+                return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "DM target parameters too long.");
+
         dm = malloc0(dm_size);
         if (!dm)
                 return log_oom();
@@ -122,7 +135,7 @@ static int dm_clone_load_table(const char *name, uint64_t size_sectors, const ch
                 /* Per linux/dm-ioctl.h: next is the byte offset from this dm_target_spec to the next one,
                  * rounded up to 8-byte alignment. With target_count == 1 next == 0 works, but set it
                  * correctly to avoid silent breakage if a second target is ever added. */
-                .next = ALIGN8(sizeof(struct dm_target_spec) + params_len),
+                .next = target_size,
         };
         strncpy(tgt->target_type, "clone", sizeof(tgt->target_type));
 
@@ -219,9 +232,14 @@ int dm_clone_send_message(const char *name, const char *message) {
         assert(name);
         assert(message);
 
-        msg_len = strlen(message) + 1;
+        msg_len = strlen(message);
         /* need to take into account both headers in size calculation */
-        dm_size = ALIGN8(sizeof(struct dm_ioctl)) + sizeof(struct dm_target_msg) + msg_len;
+        dm_size = ALIGN8(sizeof(struct dm_ioctl));
+        if (!ADD_SAFE(&msg_len, msg_len, 1) ||
+            !ADD_SAFE(&dm_size, dm_size, sizeof(struct dm_target_msg)) ||
+            !ADD_SAFE(&dm_size, dm_size, msg_len))
+                return log_error_errno(SYNTHETIC_ERRNO(EOVERFLOW), "DM target message too long.");
+
         dm = malloc0(dm_size);
         if (!dm)
                 return log_oom();
diff --git a/src/test/test-nss-hosts.c b/src/test/test-nss-hosts.c
index 61f9b153f8..761677430a 100644
--- a/src/test/test-nss-hosts.c
+++ b/src/test/test-nss-hosts.c
@@ -74,8 +74,8 @@ static void assert_myhostname_gaih_addrtuples(const struct gaih_addrtuple *tuple
         for (const struct gaih_addrtuple *it = tuples; it; it = it->next)
                 if (it->family == AF_INET)
                         assert_se(memeqzero(
-                                        (const uint8_t*) it->addr + FAMILY_ADDRESS_SIZE(AF_INET),
-                                        sizeof(it->addr) - FAMILY_ADDRESS_SIZE(AF_INET)));
+                                        (const uint8_t*) it->addr + sizeof(struct in_addr),
+                                        sizeof(it->addr) - sizeof(struct in_addr)));
 }
 
 static void print_struct_hostent(struct hostent *host, const char *canon) {