oss-fuzz/projects/dnsmasq/fuzz_patch.patch

diff --git a/src/blockdata.c b/src/blockdata.c
index f7740b5..b02915a 100644
--- a/src/blockdata.c
+++ b/src/blockdata.c
@@ -15,16 +15,22 @@
 */
 
 #include "dnsmasq.h"
+#include <assert.h>
 
 static struct blockdata *keyblock_free;
 static unsigned int blockdata_count, blockdata_hwm, blockdata_alloced;
 
+void *total_allocated[200] = {0};
+static int fuzz_total_alloc_ptr = 0;
+
 static void blockdata_expand(int n)
 {
   struct blockdata *new = whine_malloc(n * sizeof(struct blockdata));
   
   if (new)
     {
+      assert(fuzz_total_alloc_ptr < 200);
+      total_allocated[fuzz_total_alloc_ptr++] = (void*)new;
       int i;
       
       new[n-1].next = keyblock_free;
@@ -45,11 +51,23 @@ void blockdata_init(void)
   blockdata_count = 0;
   blockdata_hwm = 0;
 
+  fuzz_total_alloc_ptr = 0;
+  for (int m = 0; m < 200; m++)
+    total_allocated[m] = NULL;
+
   /* Note that daemon->cachesize is enforced to have non-zero size if OPT_DNSSEC_VALID is set */  
   if (option_bool(OPT_DNSSEC_VALID))
     blockdata_expand(daemon->cachesize);
 }
 
+void fuzz_blockdata_cleanup() {
+  for (int i = 0; i < 200; i++) {
+    if (total_allocated[i] != NULL) {
+      free(total_allocated[i]);
+    }
+  }
+}
+
 void blockdata_report(void)
 {
   my_syslog(LOG_INFO, _("pool memory in use %u, max %u, allocated %u"), 
diff --git a/src/dhcp.c b/src/dhcp.c
index 97324f2..1751df7 100644
--- a/src/dhcp.c
+++ b/src/dhcp.c
@@ -183,18 +183,26 @@ void dhcp_packet(time_t now, int pxe_fd)
     recvtime = tv.tv_sec;
 
   if (msg.msg_controllen >= sizeof(struct cmsghdr))
-    for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
-      if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
-	{
-	  union {
-	    unsigned char *c;
-	    struct in_pktinfo *p;
-	  } p;
-	  p.c = CMSG_DATA(cmptr);
-	  iface_index = p.p->ipi_ifindex;
-	  if (p.p->ipi_addr.s_addr != INADDR_BROADCAST)
-	    unicast_dest = 1;
-	}
+  {
+    int tmp_val = 0;
+      for (cmptr = CMSG_FIRSTHDR(&msg); 
+          cmptr && tmp_val < 1; 
+          tmp_val++) {
+          //cmptr = CMSG_NXTHDR(&msg, cmptr)) {
+      tmp_val++;
+          if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
+      {
+        union {
+          unsigned char *c;
+          struct in_pktinfo *p;
+        } p;
+        p.c = CMSG_DATA(cmptr);
+        iface_index = p.p->ipi_ifindex;
+        if (p.p->ipi_addr.s_addr != INADDR_BROADCAST)
+          unicast_dest = 1;
+      }
+    }
+  }
 
 #elif defined(HAVE_BSD_NETWORK) 
   if (msg.msg_controllen >= sizeof(struct cmsghdr))
diff --git a/src/dhcp6.c b/src/dhcp6.c
index 2be877f..d3f5739 100644
--- a/src/dhcp6.c
+++ b/src/dhcp6.c
@@ -116,10 +116,14 @@ void dhcp6_packet(time_t now)
   msg.msg_iov =  &daemon->dhcp_packet;
   msg.msg_iovlen = 1;
   
-  if ((sz = recv_dhcp_packet(daemon->dhcp6fd, &msg)) == -1)
+  if ((sz = recv_dhcp_packet(daemon->dhcp6fd, &msg)) == -1){
     return;
-  
-  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
+  }
+
+  int tmp_val = 0;
+//  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr)) {
+  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr && tmp_val < 1; tmp_val++) {
+    tmp_val++;
     if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
       {
 	union {
@@ -131,9 +135,11 @@ void dhcp6_packet(time_t now)
 	if_index = p.p->ipi6_ifindex;
 	dst_addr = p.p->ipi6_addr;
       }
+  }
 
-  if (!indextoname(daemon->dhcp6fd, if_index, ifr.ifr_name))
+  if (!indextoname(daemon->dhcp6fd, if_index, ifr.ifr_name)) {
     return;
+  }
 
   if ((port = relay_reply6(&from, sz, ifr.ifr_name)) != 0)
     {
diff --git a/src/netlink.c b/src/netlink.c
index 7840ef9..2419897 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -197,8 +197,13 @@ int iface_enumerate(int family, void *parm, int (*callback)())
   if (errno != 0)
     return 0;
     
+  int valval = 0;
   while (1)
     {
+      valval++;
+      if (valval > 300) {
+        return -1;
+      }
       if ((len = netlink_recv(0)) == -1)
 	{
 	  if (errno == ENOBUFS)
diff --git a/src/network.c b/src/network.c
index 3ef71b9..e305c03 100644
--- a/src/network.c
+++ b/src/network.c
@@ -697,6 +697,7 @@ int enumerate_interfaces(int reset)
   struct auth_zone *zone;
 #endif
   struct server *serv;
+  int iteration = 0;
   
   /* Do this max once per select cycle  - also inhibits netlink socket use
    in TCP child processes. */
@@ -734,6 +735,10 @@ int enumerate_interfaces(int reset)
       }
     
 again:
+  if (iteration > 100) {
+    return 0;
+  }
+  iteration += 1;
   /* Mark interfaces for garbage collection */
   for (iface = daemon->interfaces; iface; iface = iface->next) 
     iface->found = 0;