Avoid undefined behaviour as highlighted by clang

conf.h

@@ -251,8 +251,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #define CFUNSUPPORTED       (1<<7)
 #define CF__SUB_SHIFT       16
 #define CFSUB(f)            ((f) << CF__SUB_SHIFT)
-#define CF__SUBFLAGS        CFSUB(~0)
-#define CF__FLAGS           (~0 & ~CF__SUBFLAGS)
+#define CF__FLAGS           (0xFFFF)
+#define CF__SUBFLAGS        (~CF__FLAGS)
 
 strbuf strbuf_cf_flags(strbuf, int);
 strbuf strbuf_cf_flag_reason(strbuf sb, int flags);
@@ -268,7 +268,7 @@ struct cf_om_node {
     const char *key; // points inside fullkey, do not free()
     const char *text; // malloc()
     size_t nodc;
-    struct cf_om_node *nodv[10]; // malloc()
+    struct cf_om_node *nodv[0]; // malloc()
 };
 
 int is_configvarname(const char *);

keyring.c

@@ -1038,7 +1038,6 @@ static keyring_identity *keyring_unpack_identity(unsigned char *slot, const char
     unsigned char ktype = rotbuf_getc(&rbuf);
     if (rbuf.wrap || ktype == 0x00)
       break; // End of data, stop looking
-    const struct keytype *kt = &keytypes[ktype];
     size_t keypair_len;
     // No length bytes after the original four key types, for backward compatibility.  All other key
     // types are followed by a two-byte keypair length.
@@ -1047,7 +1046,7 @@ static keyring_identity *keyring_unpack_identity(unsigned char *slot, const char
     case KEYTYPE_CRYPTOSIGN:
     case KEYTYPE_RHIZOME:
     case KEYTYPE_DID:
-      keypair_len = kt->packed_size;
+      keypair_len = keytypes[ktype].packed_size;
       break;
     default:
       keypair_len = rotbuf_getc(&rbuf) << 8;
@@ -1067,9 +1066,9 @@ static keyring_identity *keyring_unpack_identity(unsigned char *slot, const char
       return NULL;
     }
     struct rotbuf rbstart = rbuf;
-    if (ktype < NELS(keytypes) && kt->unpacker) {
+    if (ktype < NELS(keytypes) && keytypes[ktype].unpacker) {
       DEBUGF(keyring, "unpack key type = 0x%02x(%s) at offset %u", ktype, keytype_str(ktype, "unknown"), (int)rotbuf_position(&rbo));
-      if (kt->unpacker(kp, &rbuf, keypair_len) != 0) {
+      if (keytypes[ktype].unpacker(kp, &rbuf, keypair_len) != 0) {
 	// If there is an error, it is probably an empty slot.
 	DEBUGF(keyring, "key type 0x%02x does not unpack", ktype);
 	keyring_free_keypair(kp);

os.c

@@ -182,7 +182,7 @@ time_ms_t sleep_ms(time_ms_t milliseconds)
   delay.tv_nsec = (milliseconds % 1000) * 1000000;
   if (nanosleep(&delay, &remain) == -1 && errno != EINTR)
     FATALF_perror("nanosleep(tv_sec=%ld, tv_nsec=%ld)", delay.tv_sec, delay.tv_nsec);
-  return remain.tv_sec * 1000 + remain.tv_nsec / 1000000;
+  return remain.tv_sec * 1000ull + remain.tv_nsec / 1000000;
 }
 
 struct timeval time_ms_to_timeval(time_ms_t milliseconds)

overlay_buffer.c

@@ -219,7 +219,8 @@ ssize_t _ob_makespace(struct __sourceloc __whence, struct overlay_buffer *b, siz
 #endif
   if (!new)
     return 0;
-  bcopy(b->bytes,new,b->position);
+  if (b->position)
+    bcopy(b->bytes,new,b->position);
   if (b->allocated) {
     assert(b->allocated == b->bytes);
     free(b->allocated);
@@ -490,7 +491,7 @@ uint32_t ob_get_ui32(struct overlay_buffer *b)
 {
   if (test_offset(b, 4))
     return 0xFFFFFFFF; // ... unsigned
-  uint32_t ret = b->bytes[b->position] << 24
+  uint32_t ret = (unsigned)b->bytes[b->position] << 24
 	| b->bytes[b->position +1] << 16
 	| b->bytes[b->position +2] << 8
 	| b->bytes[b->position +3];
@@ -505,7 +506,7 @@ uint32_t ob_get_ui32_rv(struct overlay_buffer *b)
   uint32_t ret = b->bytes[b->position]
 	| b->bytes[b->position +1] << 8
 	| b->bytes[b->position +2] << 16
-	| b->bytes[b->position +3] << 24;
+	| (unsigned)b->bytes[b->position +3] << 24;
   b->position+=4;
   return ret;
 }

overlay_interface.c

@@ -1282,6 +1282,7 @@ static int netlink_send_get()
   struct {
     struct nlmsghdr n;
     struct ifaddrmsg r;
+    uint8_t alignment_padding[64];
   } req;
   
   memset(&req, 0, sizeof(req));

overlay_mdp_services.c

@@ -78,7 +78,7 @@ int rhizome_mdp_send_block(struct subscriber *dest, const rhizome_bid_t *bid, ui
   
   int i;
   for(i=0;i<32;i++){
-    if (bitmap&(1<<(31-i)))
+    if (bitmap&(1u<<(31-i)))
       continue;
     
     if (overlay_queue_remaining(header.qos) < 10)

overlay_queue.c

@@ -610,7 +610,7 @@ int overlay_queue_ack(struct subscriber *neighbour, struct network_destination *
 	int frame_seq = frame->destinations[j].sent_sequence;
 	if (frame_seq >=0 && (frame->destinations[j].next_hop == neighbour || !frame->destination)){
 	  int seq_delta = (ack_seq - frame_seq)&0xFF;
-	  char acked = (seq_delta==0 || (seq_delta <= 32 && ack_mask&(1<<(seq_delta-1))))?1:0;
+	  char acked = (seq_delta==0 || (seq_delta <= 32 && ack_mask&((uint32_t)1<<(seq_delta-1))))?1:0;
 
 	  if (acked){
 	    int this_rtt = now - frame->destinations[j].transmit_time;

strbuf_helpers.c

@@ -474,17 +474,18 @@ strbuf strbuf_append_sockaddr(strbuf sb, const struct sockaddr *addr, socklen_t
 {
   switch (addr->sa_family) {
   case AF_UNIX: {
+      struct sockaddr_un *addr_un = (struct sockaddr_un *)addr;
       strbuf_puts(sb, "AF_UNIX:");
       size_t len = addrlen > sizeof addr->sa_family ? addrlen - sizeof addr->sa_family : 0;
-      if (addr->sa_data[0]) {
-	strbuf_toprint_quoted_len(sb, "\"\"", addr->sa_data, len);
+      if (addr_un->sun_path[0]) {
+	strbuf_toprint_quoted_len(sb, "\"\"", addr_un->sun_path, len);
 	if (len < 2)
 	  strbuf_sprintf(sb, " (addrlen=%d too short)", (int)addrlen);
-	if (len == 0 || addr->sa_data[len - 1] != '\0')
+	if (len == 0 || addr_un->sun_path[len - 1] != '\0')
 	  strbuf_sprintf(sb, " (addrlen=%d, no nul terminator)", (int)addrlen);
       } else {
 	strbuf_puts(sb, "abstract ");
-	strbuf_toprint_quoted_len(sb, "\"\"", addr->sa_data, len);
+	strbuf_toprint_quoted_len(sb, "\"\"", addr_un->sun_path, len);
 	if (len == 0)
 	  strbuf_sprintf(sb, " (addrlen=%d too short)", (int)addrlen);
       }

tests/meshms

@@ -28,6 +28,7 @@ teardown() {
    stop_all_servald_servers
    kill_all_servald_processes
    assert_no_servald_processes
+   report_all_servald_servers
 }
 
 setup_logging() {