Fix possible SEGFAULT conditions

6 files changed, 109 insertions, 28 deletions

diff --git a/src/config.c b/src/config.c
index e9a61a9..98a826f 100644
--- a/src/config.c
+++ b/src/config.c
@@ -218,6 +218,8 @@ static int set_lease(struct uci_section *s)
 		hostlen = blobmsg_data_len(c);
 
 	struct lease *lease = calloc(1, sizeof(*lease) + hostlen);
+	if (!lease)
+		goto err;
 
 	if (hostlen > 1)
 		memcpy(lease->hostname, blobmsg_get_string(c), hostlen);
@@ -233,6 +235,9 @@ static int set_lease(struct uci_section *s)
 	if ((c = tb[LEASE_ATTR_DUID])) {
 		size_t duidlen = (blobmsg_data_len(c) - 1) / 2;
 		lease->duid = malloc(duidlen);
+		if (!lease->duid)
+			goto err;
+
 		ssize_t len = odhcpd_unhexlify(lease->duid,
 				duidlen, blobmsg_get_string(c));
 
@@ -251,8 +256,10 @@ static int set_lease(struct uci_section *s)
 	return 0;
 
 err:
-	free(lease->duid);
-	free(lease);
+	if (lease) {
+		free(lease->duid);
+		free(lease);
+	}
 	return -1;
 }
 
@@ -271,6 +278,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 	struct interface *iface = get_interface(name);
 	if (!iface) {
 		iface = calloc(1, sizeof(*iface));
+		if (!iface)
+			return -1;
+
 		strncpy(iface->name, name, sizeof(iface->name) - 1);
 		list_add(&iface->head, &interfaces);
 	}
@@ -348,6 +358,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 
 			iface->upstream = realloc(iface->upstream,
 					iface->upstream_len + blobmsg_data_len(cur));
+			if (!iface->upstream)
+				goto err;
+
 			memcpy(iface->upstream + iface->upstream_len, blobmsg_get_string(cur), blobmsg_data_len(cur));
 			iface->upstream_len += blobmsg_data_len(cur);
 		}
@@ -396,10 +409,16 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 			if (inet_pton(AF_INET, blobmsg_get_string(cur), &addr4) == 1) {
 				iface->dhcpv4_dns = realloc(iface->dhcpv4_dns,
 						(++iface->dhcpv4_dns_cnt) * sizeof(*iface->dhcpv4_dns));
+				if (!iface->dhcpv4_dns)
+					goto err;
+
 				iface->dhcpv4_dns[iface->dhcpv4_dns_cnt - 1] = addr4;
 			} else if (inet_pton(AF_INET6, blobmsg_get_string(cur), &addr6) == 1) {
 				iface->dns = realloc(iface->dns,
 						(++iface->dns_cnt) * sizeof(*iface->dns));
+				if (!iface->dns)
+					goto err;
+
 				iface->dns[iface->dns_cnt - 1] = addr6;
 			} else {
 				goto err;
@@ -421,6 +440,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 				goto err;
 
 			iface->search = realloc(iface->search, iface->search_len + len);
+			if (!iface->search)
+				goto err;
+
 			memcpy(&iface->search[iface->search_len], buf, len);
 			iface->search_len += len;
 		}
@@ -467,6 +489,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 
 			int len = blobmsg_data_len(cur);
 			iface->static_ndp = realloc(iface->static_ndp, iface->static_ndp_len + len);
+			if (!iface->static_ndp)
+				goto err;
+
 			memcpy(&iface->static_ndp[iface->static_ndp_len], blobmsg_get_string(cur), len);
 			iface->static_ndp_len += len;
 		}
@@ -499,6 +524,10 @@ void odhcpd_reload(void)
 	}
 
 	struct interface *master = NULL, *i, *n;
+
+	if (!uci)
+		return;
+
 	list_for_each_entry(i, &interfaces, head)
 		clean_interface(i);
 
diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index 79fabe2..49b75f4 100644
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -61,6 +61,11 @@ int setup_dhcpv4_interface(struct interface *iface, bool enable)
 			INIT_LIST_HEAD(&iface->dhcpv4_assignments);
 
 		int sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+		if (sock < 0) {
+			syslog(LOG_ERR, "Failed to create DHCPv4 server socket: %s",
+					strerror(errno));
+			return -1;
+		}
 
 		// Basic IPv6 configuration
 		int val = 1;
@@ -139,7 +144,11 @@ int setup_dhcpv4_interface(struct interface *iface, bool enable)
 			// Construct entry
 			size_t hostlen = strlen(lease->hostname) + 1;
 			struct dhcpv4_assignment *a = calloc(1, sizeof(*a) + hostlen);
-
+			if (!a) {
+				syslog(LOG_ERR, "Calloc failed for static lease on interface %s",
+					iface->ifname);
+				return -1;
+			}
 			a->addr = ntohl(lease->ipaddr.s_addr);
 			memcpy(a->hwaddr, lease->mac.ether_addr_octet, sizeof(a->hwaddr));
 			memcpy(a->hostname, lease->hostname, hostlen);
@@ -470,6 +479,10 @@ static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 
 		if (!a && !iface->no_dynamic_dhcp) { // Create new binding
 			a = calloc(1, sizeof(*a) + hostlen);
+			if (!a) {
+				syslog(LOG_ERR, "Failed to calloc binding on interface %s", iface->ifname);
+				return NULL;
+			}
 			memcpy(a->hwaddr, mac, sizeof(a->hwaddr));
 			memcpy(a->hostname, hostname, hostlen);
 
@@ -478,6 +491,10 @@ static struct dhcpv4_assignment* dhcpv4_lease(struct interface *iface,
 
 		if (assigned && !a->hostname[0] && hostname) {
 			a = realloc(a, sizeof(*a) + hostlen);
+			if (!a) {
+				syslog(LOG_ERR, "Failed to realloc binding on interface %s", iface->ifname);
+				return NULL;
+			}
 			memcpy(a->hostname, hostname, hostlen);
 
 			// Fixup list
diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index 3defa84..205b617 100644
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -63,6 +63,11 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 
 		if (list_empty(&iface->ia_assignments)) {
 			struct dhcpv6_assignment *border = calloc(1, sizeof(*border));
+			if (!border) {
+				syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
+				return -1;
+			}
+			
 			border->length = 64;
 			list_add(&border->head, &iface->ia_assignments);
 		}
@@ -74,6 +79,12 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 		list_for_each_entry(lease, &leases, head) {
 			// Construct entry
 			struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + lease->duid_len);
+			if (!a) {
+				syslog(LOG_ERR, "Calloc failed for static lease assignment on interface %s",
+					iface->ifname);
+				return -1;
+			}
+
 			a->clid_len = lease->duid_len;
 			a->length = 128;
 			a->assigned = lease->hostid;
@@ -885,7 +896,8 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 				a->all_class = class_oro;
 				a->classes_cnt = classes_cnt;
 				a->classes = realloc(a->classes, classes_cnt * sizeof(uint16_t));
-				memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
+				if (a->classes)
+					memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
 				break;
 			}
 		}
@@ -897,28 +909,31 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 
 			if (!a && !iface->no_dynamic_dhcp) { // Create new binding
 				a = calloc(1, sizeof(*a) + clid_len);
-				a->clid_len = clid_len;
-				a->iaid = ia->iaid;
-				a->length = reqlen;
-				a->peer = *addr;
-				a->assigned = reqhint;
-				a->all_class = class_oro;
-				a->classes_cnt = classes_cnt;
-				if (classes_cnt) {
-					a->classes = malloc(classes_cnt * sizeof(uint16_t));
-					memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
-				}
+				if (a) {
+					a->clid_len = clid_len;
+					a->iaid = ia->iaid;
+					a->length = reqlen;
+					a->peer = *addr;
+					a->assigned = reqhint;
+					a->all_class = class_oro;
+					a->classes_cnt = classes_cnt;
+					if (classes_cnt) {
+						a->classes = malloc(classes_cnt * sizeof(uint16_t));
+						if (a->classes)
+							memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
+					}
 
-				if (first)
-					memcpy(a->key, first->key, sizeof(a->key));
-				else
-					odhcpd_urandom(a->key, sizeof(a->key));
-				memcpy(a->clid_data, clid_data, clid_len);
+					if (first)
+						memcpy(a->key, first->key, sizeof(a->key));
+					else
+						odhcpd_urandom(a->key, sizeof(a->key));
+					memcpy(a->clid_data, clid_data, clid_len);
 
-				if (is_pd)
-					while (!(assigned = assign_pd(iface, a)) && ++a->length <= 64);
-				else
-					assigned = assign_na(iface, a);
+					if (is_pd)
+						while (!(assigned = assign_pd(iface, a)) && ++a->length <= 64);
+					else
+						assigned = assign_na(iface, a);
+				}
 			}
 
 			if (!assigned || iface->ia_addr_len == 0) { // Set error status
@@ -959,8 +974,10 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 			} else if (assigned && hdr->msg_type == DHCPV6_MSG_REQUEST) {
 				if (hostname_len > 0) {
 					a->hostname = realloc(a->hostname, hostname_len + 1);
-					memcpy(a->hostname, hostname, hostname_len);
-					a->hostname[hostname_len] = 0;
+					if (a->hostname) {
+						memcpy(a->hostname, hostname, hostname_len);
+						a->hostname[hostname_len] = 0;
+					}
 				}
 				a->accept_reconf = accept_reconf;
 				apply_lease(iface, a, true);
diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 9515f40..7560a75 100644
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -40,6 +40,11 @@ static struct odhcpd_event dhcpv6_event = {{.fd = -1}, handle_dhcpv6};
 int init_dhcpv6(void)
 {
 	int sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
+	if (sock < 0) {
+		syslog(LOG_ERR, "Failed to create DHCPv6 server socket: %s",
+				strerror(errno));
+		return -1;
+	}
 
 	// Basic IPv6 configuration
 	int val = 1;
@@ -91,8 +96,7 @@ int setup_dhcpv6_interface(struct interface *iface, bool enable)
 					IPV6_ADD_MEMBERSHIP, &server, sizeof(server));
 	}
 
-	setup_dhcpv6_ia_interface(iface, enable);
-	return 0;
+	return setup_dhcpv6_ia_interface(iface, enable);
 }
 
 
diff --git a/src/ndp.c b/src/ndp.c
index 89bcd3c..bd62068 100644
--- a/src/ndp.c
+++ b/src/ndp.c
@@ -160,10 +160,19 @@ int setup_ndp_interface(struct interface *iface, bool enable)
 
 		if (iface->static_ndp_len) {
 			char *entry = alloca(iface->static_ndp_len), *saveptr;
+			if (!entry) {
+				syslog(LOG_ERR, "Alloca failed for static NDP list");
+				return -1;
+			}
 			memcpy(entry, iface->static_ndp, iface->static_ndp_len);
 
 			for (entry = strtok_r(entry, " ", &saveptr); entry; entry = strtok_r(NULL, " ", &saveptr)) {
 				struct ndp_neighbor *n = malloc(sizeof(*n));
+				if (!n) {
+					syslog(LOG_ERR, "Malloc failed for static NDP-prefix %s", entry);
+					return -1;
+				}
+
 				n->iface = iface;
 				n->timeout = 0;
 
diff --git a/src/router.c b/src/router.c
index 5abf1e6..83da938 100644
--- a/src/router.c
+++ b/src/router.c
@@ -353,6 +353,11 @@ static void send_router_advert(struct uloop_timeout *event)
 		uint32_t lifetime;
 		uint8_t name[];
 	} *search = alloca(sizeof(*search) + search_padded);
+
+	if (!search) {
+		syslog(LOG_ERR, "Alloca failed for dns search on interface %s", iface->ifname);
+		return;
+	}
 	search->type = ND_OPT_DNS_SEARCH;
 	search->len = search_len ? ((sizeof(*search) + search_padded) / 8) : 0;
 	search->pad = 0;