Preserve existing log file permissions when adding group-write bit.

Commit 1f8f78a49b ("Add root group writeable flag to log file")
introduced a fchmod() call in log_start() that resets the file mode
to a hardcoded value (0660), discarding any pre-existing permissions.
This broke our usage of dnsmasq where we create the log file with
specific permissions before starting dnsmasq in an LXC container
namespace, so that unprivileged users inside the container can read
the log. The hardcoded mode strips those permissions on startup.

Use the existing stat result to OR in S_IWGRP instead, equivalent
to chmod g+w, so that only the group-write bit is added without
disturbing other permission bits.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG

@@ -28,6 +28,12 @@ version 2.93
 	relay is in use. Many thanks to Jørgen Søvik for help
 	finding this bug.
 	
+	Modify the inotify implementation so that inotify watches are
+	only created after dnsmasq has changed permissions and userid.
+	This means that the permissions used when creating the watches
+	are the same as used for accessing watched files, which makes
+	more sense and avoids odd and confusing error conditions.
+
 	
 version 2.92
         Redesign the interaction between DNSSEC validation and per-domain

Makefile

@@ -1,4 +1,4 @@
-# dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+# dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by

man/dnsmasq.8

@@ -1515,7 +1515,7 @@ The normal default DNS server (the same address as the DHCP server)
 will not be appropriate when there is no route bewteen the
 two, so this will have to be explicitly configured. 
 .TP
-.B \-U, --dhcp-vendorclass=set:<tag>,[enterprise:<IANA-enterprise number>,]<vendor-class>
+.B \-U, --dhcp-vendorclass=set:<tag>,[enterprise:<IANA-enterprise number>,][<vendor-class>]
 Map from a vendor-class string to a tag. Most DHCP clients provide a 
 "vendor class" which represents, in some sense, the type of host. This option 
 maps vendor classes to tags, so that DHCP options may be selectively delivered
@@ -1529,9 +1529,11 @@ allow fuzzy matching. The set: prefix is optional but allowed for
 consistency. 
 
 Note that in IPv6 only, vendorclasses are namespaced with an 
-IANA-allocated enterprise number. This is given with enterprise:
+IANA-allocated enterprise number. This may be given with an enterprise:
 keyword and specifies that only vendorclasses matching the specified
-number should be searched.
+number should be searched. Similarly, an enterprise number may be given
+with no vendor-class string. This always matches vendorclasses with
+the given enterprise number.
 .TP
 .B \-j, --dhcp-userclass=set:<tag>,<user-class>
 Map from a user-class string to a tag (with substring

src/arp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/auth.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -591,7 +591,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
   if (auth && zone)
     {
       char *authname;
-      int newoffset, offset = 0;
+      int newoffset = ansp - (unsigned char *)header, offset = 0;
 
       if (!subnet)
 	authname = zone->domain;
@@ -631,8 +631,7 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 	}
       
       /* handle NS and SOA in auth section or for explicit queries */
-       newoffset = ansp - (unsigned char *)header;
-       if (((anscount == 0 && !ns) || soa) &&
+      if (((anscount == 0 && !ns) || soa) &&
 	  add_resource_record(header, limit, &trunc, 0, &ansp, 
 			      daemon->auth_ttl, NULL, T_SOA, C_IN, "ddlllll",
 			      authname, daemon->authserver,  daemon->hostmaster,
@@ -650,11 +649,10 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
       if (anscount != 0 || ns)
 	{
 	  struct name_list *secondary;
-	  
+	 	  
 	  /* Only include the machine running dnsmasq if it's acting as an auth server */
 	  if (daemon->authinterface)
 	    {
-	      newoffset = ansp - (unsigned char *)header;
 	      if (add_resource_record(header, limit, &trunc, -offset, &ansp, 
 				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", offset == 0 ? authname : NULL, daemon->authserver))
 		{
@@ -669,9 +667,11 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
 
 	  if (!subnet)
 	    for (secondary = daemon->secondary_forward_server; secondary; secondary = secondary->next)
-	      if (add_resource_record(header, limit, &trunc, offset, &ansp, 
-				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", secondary->name))
+	      if (add_resource_record(header, limit, &trunc, -offset, &ansp, 
+				      daemon->auth_ttl, NULL, T_NS, C_IN, "d", offset == 0 ? authname : NULL, secondary->name))
 		{
+		  if (offset == 0) 
+		    offset = newoffset;
 		  if (ns) 
 		    anscount++;
 		  else

src/blockdata.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/bpf.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/cache.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -1083,6 +1083,9 @@ int cache_recv_insert(time_t now, int fd)
 	     !read_write(fd, (unsigned char *)&validatecount, sizeof(validatecount), RW_READ) ||
 	     !read_write(fd, (unsigned char *)&validatecountp, sizeof(validatecountp), RW_READ)))
 	  return 0;
+
+	if (op == PIPE_OP_KILLED)
+	  my_syslog(LOG_INFO, _("TCP process for DNSSEC validation timed out"));
 	
 	/* There's a tiny chance that the frec may have been freed 
 	   and reused before the TCP process returns. Detect that with
@@ -1600,7 +1603,7 @@ void cache_reload(void)
   
 #ifdef HAVE_DNSSEC
   for (ds = daemon->ds; ds; ds = ds->next)
-    if ((cache = get_config_crec()))
+    if (ds->name && (cache = get_config_crec()))
       {
 	
 	if (!(cache->addr.ds.keydata = blockdata_alloc(ds->digest, ds->digestlen)))
@@ -2328,7 +2331,7 @@ void log_query(unsigned int flags, char *name, union all_addr *addr, char *arg,
     return;
 
   /* build query type string if requested */
-  if (!(flags & (F_SERVER | F_IPSET | F_QUERY)) && type > 0)
+  if (!(flags & (F_SERVER | F_IPSET | F_QUERY | F_KEYTAG | F_RR)) && type > 0)
     arg = querystr(arg, type);
 
   dest = arg;
@@ -2344,19 +2347,25 @@ void log_query(unsigned int flags, char *name, union all_addr *addr, char *arg,
     {
       dest = daemon->addrbuff;
 
-       if (flags & F_RR)
-	 {
-	   if (flags & F_KEYTAG)
-	     dest = querystr(NULL, addr->rrblock.rrtype);
-	   else
-	     dest = querystr(NULL, addr->rrdata.rrtype);
-	 }
-       else if (flags & F_KEYTAG)
-	sprintf(daemon->addrbuff, arg, addr->log.keytag, addr->log.algo, addr->log.digest);
+      if (flags & F_RR)
+	{
+	  if (flags & F_KEYTAG)
+	    dest = querystr(NULL, addr->rrblock.rrtype);
+	  else
+	    dest = querystr(NULL, addr->rrdata.rrtype);
+	}
+#ifdef HAVE_DNSSEC
+      else if (flags & F_KEYTAG)
+	{
+	  snprintf(daemon->addrbuff, ADDRSTRLEN, arg, addr->log.keytag, addr->log.algo, addr->log.digest);
+	  if (type)
+	    extra = " (not supported)";
+	}
+#endif
       else if (flags & F_RCODE)
 	{
 	  unsigned int rcode = addr->log.rcode;
-
+	  
 	  if (rcode == SERVFAIL)
 	    dest = "SERVFAIL";
 	  else if (rcode == REFUSED)

src/config.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -15,7 +15,7 @@
 */
 
 #define FTABSIZ 150 /* max number of outstanding requests (default) */
-#define MAX_PROCS 20 /* default max no children for TCP requests */
+#define MAX_PROCS 30 /* default max no children for TCP requests */
 #define CHILD_LIFETIME 150 /* secs 'till terminated (RFC1035 suggests > 120s) */
 #define TCP_MAX_QUERIES 100 /* Maximum number of queries per incoming TCP connection */
 #define TCP_TIMEOUT 5 /* timeout waiting to connect to an upstream server - double this for answer */

src/conntrack.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/crypto.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -93,7 +93,15 @@ static void null_hash_update(void *ctxv, size_t length, const uint8_t *src)
   memcpy(null_hash_buff + ctx->len, src, length);
   ctx->len += length;
 }
- 
+
+/* The prototype changes in nettle 4.0 to omit the length argument */
+#if MIN_VERSION(4, 0)
+static void null_hash_digest(void *ctx, uint8_t *dst)
+{
+  ((struct null_hash_digest *)dst)->buff = null_hash_buff;
+  ((struct null_hash_digest *)dst)->len = ((struct null_hash_ctx *)ctx)->len;
+}
+#else
 static void null_hash_digest(void *ctx, size_t length, uint8_t *dst)
 {
   (void)length;
@@ -101,6 +109,7 @@ static void null_hash_digest(void *ctx, size_t length, uint8_t *dst)
   ((struct null_hash_digest *)dst)->buff = null_hash_buff;
   ((struct null_hash_digest *)dst)->len = ((struct null_hash_ctx *)ctx)->len;
 }
+#endif
 
 static struct nettle_hash null_hash = {
   "null_hash",
@@ -501,4 +510,16 @@ const struct nettle_hash *hash_find(char *name)
 #endif
 }
 
+/* The prototype changes in nettle 4.0 to omit the length argument */
+void nettle_digest_wrapper(const struct nettle_hash *hash, void *ctx, size_t length, uint8_t *dst)
+{
+#if MIN_VERSION(4, 0)
+  (void)length;
+  hash->digest(ctx, dst);
+#else
+  hash->digest(ctx, length, dst);
+#endif
+}
+
+
 #endif /* defined(HAVE_DNSSEC) */

src/dbus.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dhcp-common.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -882,7 +882,7 @@ char *option_string(int prot, unsigned int opt, unsigned char *val, int opt_len,
 			 buf[j++] = c;
 		     }
 		    i = l;
-		    if (val[i] != 0 && j < buf_len)
+		    if (i < opt_len && val[i] != 0 && j < buf_len)
 		      buf[j++] = '.';
 		  }
 	      }
@@ -892,24 +892,23 @@ char *option_string(int prot, unsigned int opt, unsigned char *val, int opt_len,
 		unsigned char *p;
 
 		i = 0, j = 0;
-		while (1)
+		while (i + 2 <= opt_len)
 		  {
 		    p = &val[i];
 		    GETSHORT(len, p);
+		    if (i + 2 + len > opt_len)
+		      break; /* malformed: body extends beyond option */
 		    for (k = 0; k < len && j < buf_len; k++)
 		      {
 		       char c = *p++;
 		       if (isprint((unsigned char)c))
 			 buf[j++] = c;
 		     }
-		    i += len +2;
-		    if (i >= opt_len)
-		      break;
-
-		    if (j < buf_len)
+		    i += len + 2;
+		    if (i < opt_len && j < buf_len)
 		      buf[j++] = ',';
 		  }
-	      }	      
+	      }
 #endif
 	    else if ((ot[o].size & (OT_DEC | OT_TIME)) && opt_len != 0)
 	      {

src/dhcp-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dhcp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dhcp6-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dhcp6.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dns-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/dnsmasq.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -199,7 +199,7 @@ int main (int argc, char **argv)
       /* Must have at least a root trust anchor, or the DNSSEC code
 	 can loop forever. */
       for (ds = daemon->ds; ds; ds = ds->next)
-	if (ds->name[0] == 0)
+	if (ds->name && ds->name[0] == 0)
 	  break;
 
       if (!ds)
@@ -437,14 +437,6 @@ int main (int argc, char **argv)
 	daemon->tcp_pipes[i] = -1;
     }
 
-#ifdef HAVE_INOTIFY
-  if ((daemon->port != 0 && !option_bool(OPT_NO_RESOLV)) ||
-      daemon->dynamic_dirs)
-    inotify_dnsmasq_init();
-  else
-    daemon->inotifyfd = -1;
-#endif
-
   if (daemon->dump_file)
 #ifdef HAVE_DUMPFILE
     dump_init();
@@ -864,6 +856,14 @@ int main (int argc, char **argv)
     }
 #endif
 
+#ifdef HAVE_INOTIFY
+  if ((daemon->port != 0 && !option_bool(OPT_NO_RESOLV)) ||
+      daemon->dynamic_dirs)
+    inotify_dnsmasq_init(err_pipe[1]);
+  else
+    daemon->inotifyfd = -1;
+#endif
+  
    /* Don't start logging malloc before logging is set up. */
   daemon->log_malloc = option_bool(OPT_LOG_MALLOC);
   
@@ -946,9 +946,27 @@ int main (int argc, char **argv)
 	my_syslog(LOG_INFO, _("DNSSEC signature timestamps not checked until system time valid"));
 
       for (ds = daemon->ds; ds; ds = ds->next)
-	my_syslog(LOG_INFO,
-		  ds->digestlen == 0 ? _("configured with negative trust anchor for %s") : _("configured with trust anchor for %s keytag %u"),
-		  ds->name[0] == 0 ? "<root>" : ds->name, ds->keytag);
+	{
+	  struct ds_config *ds1;
+	  
+	  for (ds1 = ds->next; ds1; ds1 = ds1->next)
+	    if (strcmp(ds->name, ds1->name) == 0 &&
+		ds->digestlen == ds1->digestlen &&
+		(ds->digestlen == 0 ||
+		 (ds->algo == ds1->algo &&
+		  ds->keytag == ds1->keytag &&
+		  ds->digest_type == ds1->digest_type &&
+		  memcmp(ds->digest, ds1->digest, ds->digestlen) == 0)))
+	      {
+		ds->name = NULL; /* Mark as duplicate */
+		break;
+	      }
+	  
+	  if (ds->name)
+	    my_syslog(LOG_INFO,
+		      ds->digestlen == 0 ? _("configured with negative trust anchor for %s") : _("configured with trust anchor for %s keytag %u"),
+		      ds->name[0] == 0 ? "<root>" : ds->name, ds->keytag);
+	}
     }
 #endif
 
@@ -1367,8 +1385,6 @@ static void sig_handler(int sig)
 		  read_write(daemon->pipe_to_parent, (unsigned char *)(&daemon->forward_to_tcp), sizeof(daemon->forward_to_tcp), RW_WRITE);
 		  read_write(daemon->pipe_to_parent, (unsigned char *)(&daemon->forward_to_tcp->uid), sizeof(daemon->forward_to_tcp->uid), RW_WRITE);
 
-		  my_syslog(LOG_INFO, _("TCP process for DNSSEC validation timed out"));
-
 		  _exit(0);
 		}
 	    }
@@ -1527,6 +1543,26 @@ static void fatal_event(struct event_desc *ev, char *msg)
       /* fall through */
     case EVENT_TIME_ERR:
       die(_("cannot create timestamp file %s: %s" ), msg, EC_BADCONF);
+
+      /* fall through */
+    case EVENT_LINK_ERR:
+      die(_("cannot access path %s: %s" ), msg, EC_MISC);
+
+       /* fall through */
+    case EVENT_INOTFY_ERR:
+      die(_("failed to create inotify: %s" ), NULL, EC_MISC);
+
+      /* fall through */
+    case EVENT_TMSL_ERR:
+      die(_("too many symlinks following %s"), msg, EC_MISC);
+
+      /* fall through */
+    case EVENT_RESOLV_ERR:
+      die(_("directory %s for resolv-file is missing, cannot poll"), msg, EC_MISC);
+
+      /* fall through */
+    case EVENT_IFILE_ERR:
+      die(_("failed to create inotify for %s: %s"), msg, EC_MISC);
     }
 }	
       

src/dnsmasq.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
  
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -14,7 +14,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#define COPYRIGHT "Copyright (c) 2000-2025 Simon Kelley"
+#define COPYRIGHT "Copyright (c) 2000-2026 Simon Kelley"
 
 /* We do defines that influence behavior of stdio.h, so complain
    if included too early. */
@@ -201,6 +201,11 @@ struct event_desc {
 #define EVENT_TIME_ERR   24
 #define EVENT_SCRIPT_LOG 25
 #define EVENT_TIME       26
+#define EVENT_LINK_ERR   27
+#define EVENT_INOTFY_ERR 28
+#define EVENT_TMSL_ERR   29
+#define EVENT_RESOLV_ERR 30
+#define EVENT_IFILE_ERR  31
 
 /* Exit codes. */
 #define EC_GOOD        0
@@ -1468,6 +1473,7 @@ int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, ch
 			  char *keyname, int class, int *validate_count);
 int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char *name,
 		       char *keyname, int class, int *validate_count);
+int cache_neg_ds(char *name, int flags, int class, time_t now, int neg_ttl);
 int dnssec_validate_reply(time_t now, struct dns_header *header, size_t plen, char *name, char *keyname, int *class,
 			  int check_unsigned, int *neganswer, int *prim_ok, int *nons, int *nsec_ttl, int *validate_count);
 int dnskey_keytag(int alg, int flags, unsigned char *key, int keylen);
@@ -1484,6 +1490,7 @@ int verify(struct blockdata *key_data, unsigned int key_len, unsigned char *sig,
 char *ds_digest_name(int digest);
 char *algo_digest_name(int algo);
 char *nsec3_digest_name(int digest);
+void nettle_digest_wrapper(const struct nettle_hash *hash, void *ctx, size_t length, uint8_t *dst);
 
 /* util.c */
 void rand_init(void);
@@ -1497,11 +1504,13 @@ unsigned char *do_rfc1035_name(unsigned char *p, char *sval, char *limit);
 void *safe_malloc(size_t size);
 void safe_strncpy(char *dest, const char *src, size_t size);
 void safe_pipe(int *fd, int read_noblock);
+#define malloc_log(x, y) malloc_log_real(__func__, __LINE__, (x), (y))
 #define whine_malloc(x) whine_malloc_real(__func__, __LINE__, (x))
 #define whine_realloc(x, y) whine_realloc_real(NULL, __func__, __LINE__, (x), (y))
 #define expand_buf(x, y) expand_buf_real(__func__, __LINE__, (x), (y))
 #define expand_workspace(x, y, z) expand_workspace_real(__func__, __LINE__, (x), (y), (z))
 #define free(x) free_real(__func__, __LINE__, (x))
+void malloc_log_real(const char *func, unsigned int line, void *mem, size_t size);
 void free_real(const char *func, unsigned int line, void *ptr);
 void *whine_malloc_real(const char *func, unsigned int line, size_t size);
 void *whine_realloc_real(const char *wrapper, const char *func, unsigned int line, void *ptr, size_t size);
@@ -1905,7 +1914,7 @@ int detect_loop(char *query, int type);
 
 /* inotify.c */
 #ifdef HAVE_INOTIFY
-void inotify_dnsmasq_init(void);
+void inotify_dnsmasq_init(int errfd);
 int inotify_check(time_t now);
 void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revhashsz);
 #endif

src/dnssec.c

@@ -1,5 +1,5 @@
 /* dnssec.c is Copyright (c) 2012 Giovanni Bajo <rasky@develer.com>
-           and Copyright (c) 2012-2025 Simon Kelley
+           and Copyright (c) 2012-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -656,7 +656,7 @@ static int validate_rrset(time_t now, struct dns_header *header, size_t plen, in
 	    }
 	}
      
-      hash->digest(ctx, hash->digest_size, digest);
+      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
       
       /* namebuff used for workspace above, restore to leave unchanged on exit */
       p = (unsigned char*)(rrset[0]);
@@ -836,7 +836,7 @@ int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, ch
 		 rather then O(keys x DSs) */
 	      hash->update(ctx, (unsigned int)wire_len, (unsigned char *)name);
 	      hash->update(ctx, (unsigned int)rdlen, psave);
-	      hash->digest(ctx, hash->digest_size, digest);
+	      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
 	      
 	      from_wire(name);
 
@@ -950,10 +950,7 @@ int dnssec_validate_by_ds(time_t now, struct dns_header *header, size_t plen, ch
 			   
 			   a.log.keytag = keytag;
 			   a.log.algo = algo;
-			   if (algo_digest_name(algo))
-			     log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu", 0);
-			   else
-			     log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu (not supported)", 0);
+			   log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DNSKEY keytag %hu, algo %hu", !algo_digest_name(algo));
 			 }
 		     }
 				  
@@ -1027,21 +1024,21 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
 		  (flags = in_arpa_name_2_addr(name, &a)) &&
 		  ((flags == F_IPV6 && private_net6(&a.addr6, 0)) || (flags == F_IPV4 && private_net(a.addr4, 0))))
 		{
-		  my_syslog(LOG_INFO, _("Insecure reply received for DS %s, assuming that's OK for a RFC-1918 address."), name);
+		  my_syslog(LOG_INFO, _("insecure reply received for DS %s, assuming that's OK for a RFC-1918 address"), name);
 		  neganswer = 1;
 		  nons = 0; /* If we're faking a DS, fake one with an NS. */
 		  neg_ttl = DNSSEC_ASSUMED_DS_TTL;
 		}
 	      else if (lookup_domain(name, F_DOMAINSRV, NULL, NULL))
 		{
-		  my_syslog(LOG_INFO, _("Insecure reply received for DS %s, assuming non-DNSSEC domain-specific server."), name);
+		  my_syslog(LOG_INFO, _("insecure reply received for DS %s, assuming non-DNSSEC domain-specific server"), name);
 		  neganswer = 1;
 		  nons = 0; /* If we're faking a DS, fake one with an NS. */
 		  neg_ttl = DNSSEC_ASSUMED_DS_TTL;
 		}
 	      else
 		{
-		  my_syslog(LOG_WARNING, _("Insecure DS reply received for %s, check domain configuration and upstream DNS server DNSSEC support"), name);
+		  my_syslog(LOG_WARNING, _("insecure DS reply received for %s, check domain configuration and upstream DNS server DNSSEC support"), name);
 		  log_query(F_NOEXTRA | F_UPSTREAM, name, NULL, "BOGUS DS - not secure", 0);
 		  return STAT_BOGUS | DNSSEC_FAIL_INDET; 
 		}
@@ -1101,7 +1098,7 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
 		  a.log.keytag = keytag;
 		  a.log.algo = algo;
 		  a.log.digest = digest;
-		  log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DS for keytag %hu, algo %hu, digest %hu (not supported)", 0);
+		  log_query(F_NOEXTRA | F_KEYTAG | F_UPSTREAM, name, &a, "DS for keytag %hu, algo %hu, digest %hu", 1);
 		  neg_ttl = ttl;
 		} 
 	      else if ((key = blockdata_alloc((char*)p, rdlen - 4)))
@@ -1141,44 +1138,47 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char
     }
   
   flags = F_FORWARD | F_DS | F_NEG | F_DNSSECOK;
-  
+
   if (neganswer)
     {
       if (RCODE(header) == NXDOMAIN)
 	flags |= F_NXDOMAIN;
       
-      /* We only cache validated DS records, DNSSECOK flag hijacked 
-	 to store presence/absence of NS. */
       if (nons)
 	{
 	  if (lookup_domain(name, F_DOMAINSRV, NULL, NULL))
 	    {
-	      my_syslog(LOG_WARNING, _("Negative DS reply without NS record received for %s, assuming non-DNSSEC domain-specific server."), name);
+	      my_syslog(LOG_WARNING, _("negative DS reply without NS record received for %s, assuming non-DNSSEC domain-specific server"), name);
 	      nons = 0;
+	      neg_ttl = DNSSEC_ASSUMED_DS_TTL;
 	    }
 	  else
 	    /* We only cache validated DS records, DNSSECOK flag hijacked 
 	       to store presence/absence of NS. */
 	    flags &= ~F_DNSSECOK;
 	}
+      
+      log_query(F_NOEXTRA | F_UPSTREAM, name, NULL,
+		servfail ? "SERVFAIL" : (nons ? "no DS/cut" : "no DS"), 0);
     }
-
+  
+  return cache_neg_ds(name, flags, class, now, neg_ttl);
+  
+}
+       
+int cache_neg_ds(char *name, int flags, int class, time_t now, int ttl)
+{
   cache_start_insert();
   
   /* Use TTL from NSEC for negative cache entries */
-  if (!cache_insert(name, NULL, class, now, neg_ttl, flags))
+  if (!cache_insert(name, NULL, class, now, ttl, flags))
     return STAT_ABANDONED;
   
   cache_end_insert();  
   
-  if (neganswer)
-    log_query(F_NOEXTRA | F_UPSTREAM, name, NULL,
-	      servfail ? "SERVFAIL" : (nons ? "no DS/cut" : "no DS"), 0);
-      
   return STAT_OK;
 }
 
-
 /* 4034 6.1 */
 static int hostname_cmp(const char *a, const char *b)
 {
@@ -1385,13 +1385,13 @@ static int hash_name(char *in, unsigned char **out, struct nettle_hash const *ha
  
   hash->update(ctx, to_wire(in), (unsigned char *)in);
   hash->update(ctx, salt_len, salt);
-  hash->digest(ctx, hash->digest_size, digest);
+  nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
 
   for(i = 0; i < iterations; i++)
     {
       hash->update(ctx, hash->digest_size, digest);
       hash->update(ctx, salt_len, salt);
-      hash->digest(ctx, hash->digest_size, digest);
+      nettle_digest_wrapper(hash, ctx, hash->digest_size, digest);
     }
    
   from_wire(in);

src/domain-match.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -79,7 +79,9 @@ void build_server_array(void)
   for (serv = daemon->local_domains; serv; serv = serv->next, count++)
     daemon->serverarray[count] = serv;
   
-  qsort(daemon->serverarray, daemon->serverarraysz, sizeof(struct server *), order_qsort);
+  /* serverarray may be unallocated if we have no servers yet. */
+  if (daemon->serverarray)
+    qsort(daemon->serverarray, daemon->serverarraysz, sizeof(struct server *), order_qsort);
   
   /* servers need the location in the array to find all the whole
      set of equivalent servers from a pointer to a single one. */

src/domain.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -175,8 +175,8 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
 	       *p = '-';
 	 }
        
-       strncat(name, ".", MAXDNAME);
-       strncat(name, c->domain, MAXDNAME);
+       strncat(name, ".", MAXDNAME - strlen(name) - 1);
+       strncat(name, c->domain, MAXDNAME - strlen(name) - 1);
 
        return 1;
      }
@@ -201,16 +201,16 @@ int is_rev_synth(int flag, union all_addr *addr, char *name)
 	   for (i = 0; i < 16; i += 2)
 	     {
 	       sprintf(frag, "%s%02x%02x",  i == 0 ? "" : "-", addr->addr6.s6_addr[i], addr->addr6.s6_addr[i+1]);
-	       strncat(name, frag, MAXDNAME);
+	       strncat(name, frag, MAXDNAME - strlen(name) - 1);
 	     }
 	 }
 
-       strncat(name, ".", MAXDNAME);
-       strncat(name, c->domain, MAXDNAME);
-       
+       strncat(name, ".", MAXDNAME - strlen(name) - 1);
+       strncat(name, c->domain, MAXDNAME - strlen(name) - 1);
+
        return 1;
      }
-   
+
    return 0;
 }
 

src/dump.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -85,7 +85,8 @@ void dump_init(void)
       /* count existing records */
       while (read_write(daemon->dumpfd, (void *)&pcap_header, sizeof(pcap_header), RW_READ))
 	{
-	  lseek(daemon->dumpfd, pcap_header.incl_len, SEEK_CUR);
+	  if (lseek(daemon->dumpfd, pcap_header.incl_len, SEEK_CUR) == (off_t)-1)
+	    break;
 	  packet_count++;
 	}
     }

src/edns0.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -469,6 +469,8 @@ int check_source(struct dns_header *header, size_t plen, unsigned char *pseudohe
      {
        GETSHORT(code, p);
        GETSHORT(len, p);
+       if (i + 4 + len > rdlen)
+	 break; /* malformed: option body extends beyond RDATA */
        if (code == EDNS0_OPTION_CLIENT_SUBNET)
 	 {
 	   if (peer)

src/forward.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -954,6 +954,7 @@ static void dnssec_validate(struct frec *forward, struct dns_header *header,
 	  /* As soon as anything returns BOGUS, we stop and unwind, to do otherwise
 	     would invite infinite loops, since the answers to DNSKEY and DS queries
 	     will not be cached, so they'll be repeated. */
+	ds_retry:
 	  if (forward->flags & FREC_DNSKEY_QUERY)
 	    status = dnssec_validate_by_ds(now, header, plen, daemon->namebuff, daemon->keyname, forward->class, &orig->validate_counter);
 	  else if (forward->flags & FREC_DS_QUERY)
@@ -1083,6 +1084,18 @@ static void dnssec_validate(struct frec *forward, struct dns_header *header,
 				       STAT_ISEQUAL(status, STAT_NEED_KEY) ? "dnssec-query[DNSKEY]" : "dnssec-query[DS]", 0);
 		  return;
 		}
+
+	      /* If there's no server for the parent of a domain-specific server's domain,
+		 assume that said server's contents it legitimately unsigned, as if the parent
+		 contained a negative DS record. This is part of the same logic that's found
+		 in dnssec_validate_ds() when it gets a negative DS repsonse. */
+	      if (STAT_ISEQUAL(status, STAT_NEED_DS) && serverind == -1 && lookup_domain(daemon->keyname, F_DOMAINSRV, NULL, NULL) &&
+		  cache_neg_ds(daemon->keyname, F_FORWARD | F_DS | F_NEG | F_DNSSECOK, forward->class, now, DNSSEC_ASSUMED_DS_TTL) == STAT_OK)
+		{
+		  my_syslog(LOG_WARNING, _("no server for parent domain of %s, assuming unsigned domain"), daemon->keyname);
+		  blockdata_free(stash);
+		  goto ds_retry;
+		}
 	      
 	      /* error unwind */
 	      free_rfds(&rfds);
@@ -1192,10 +1205,10 @@ void reply_query(int fd, time_t now)
 	  server = daemon->serverarray[serv];
 	  if (server->sfd && server->sfd->fd == fd)
 	    break;
-
-	  if (serv == last)
-	    return;
 	}
+
+      if (serv == last)
+	return;
     }
   
   /* spoof check: answer must come from known server, also
@@ -2162,9 +2175,12 @@ static ssize_t tcp_talk(int first, int last, int start, struct dns_header *heade
 	     someone might be attempting to insert bogus values into the cache by 
 	     sending replies containing questions and bogus answers.
 	     Try another server, or give up */
-	  p = (unsigned char *)(((struct dns_header *)recvbuff->iov_base)+1);
-	  if (extract_name(((struct dns_header *)recvbuff->iov_base), rsize, &p, daemon->namebuff, EXTR_NAME_COMPARE, 4) != 1)
+	  struct dns_header *header = (struct dns_header *)recvbuff->iov_base;
+	  p = (unsigned char *)(header+1);
+	  if (rsize < (unsigned int)sizeof(struct dns_header) || !(header->hb3 & HB3_QR) || ntohs(header->qdcount) != 1 ||
+	      extract_name(header, rsize, &p, daemon->namebuff, EXTR_NAME_COMPARE, 4) != 1)
 	    continue;
+	  
 	  GETSHORT(rtype, p); 
 	  GETSHORT(rclass, p);
       
@@ -2442,25 +2458,34 @@ void tcp_request(int confd, time_t now, struct iovec *bigbuff,
 	    break;
 	  
 	  /* Now get the query into the normal UDP packet buffer.
-	     Ignore queries long than this. If we're answering locally,
+	     Ignore queries longer than this. If we're answering locally,
 	     copy the query into the output buffer, but for forwarding, tcp_talk()
-	     wants the query in a a different buffer from the reply.
-	     Note that we overwrote any saved UDP query - this onlt matters in debug mode. */
+	     wants the query in  different buffer from the reply.
+	     Note that we overwrote any saved UDP query - this only matters in debug mode. */
 	  daemon->srv_save = NULL;
 	  if (!read_write(confd, (unsigned char *)&tcp_len, sizeof(tcp_len), RW_READ) ||
 	      !(size = ntohs(tcp_len)) || size > (size_t)daemon->packet_buff_sz ||
 	      !read_write(confd, (unsigned char *)daemon->packet, size, RW_READ))
 	    break;
 	  
-	  if (size < (int)sizeof(struct dns_header))
+	  /* header == query */
+	  header = (struct dns_header *)daemon->packet;
+
+	  if (size < (int)sizeof(struct dns_header) || (header->hb3 & HB3_QR))
 	    continue;
 	  
 	  /* Make sure we have a buffer big enough for the largest answer. */
 	  expand_buf(bigbuff, 65536 + MAXDNAME + RRFIXEDSZ);
 	  out_header = bigbuff->iov_base;
 	  
-	  /* header == query */
-	  header = (struct dns_header *)daemon->packet;
+	  /* Add edns0 pheader to query */
+	  size = add_edns0_config(header, size, ((unsigned char *) header) + daemon->packet_buff_sz, &peer_addr, now, &cacheable);
+
+	  /* Clear buffer to avoid risk of information disclosure. */
+	  memset(bigbuff->iov_base, 0, bigbuff->iov_len);
+	  /* Copy query into output buffer for local answering */
+	  memcpy(out_header, header, size);	    
+	      
 	  query_count++;
 	  
 	  /* log_query gets called indirectly all over the place, so 
@@ -2493,13 +2518,6 @@ void tcp_request(int confd, time_t now, struct iovec *bigbuff,
 		    do_bit = 1; /* do bit */ 
 		}
 
-	      size = add_edns0_config(header, size, ((unsigned char *) header) + daemon->edns_pktsz, &peer_addr, now, &cacheable);
-
-	      /* Clear buffer to avoid risk of information disclosure. */
-	      memset(bigbuff->iov_base, 0, bigbuff->iov_len);
-	      /* Copy query into output buffer for local answering */
-	      memcpy(out_header, header, size);	    
-	      
 	      log_query_mysockaddr((auth_dns ? F_NOERR | F_AUTH : 0) | F_QUERY | F_FORWARD, daemon->namebuff,
 				   &peer_addr, NULL, qtype);
 	      
@@ -2552,7 +2570,7 @@ void tcp_request(int confd, time_t now, struct iovec *bigbuff,
 	      else if (!allowed)
 		{
 		  ede = EDE_BLOCKED;
-		  m = answer_disallowed(header, size, (u32)mark, daemon->namebuff);
+		  m = answer_disallowed(out_header, size, (u32)mark, daemon->namebuff);
 		}
 #endif
 #ifdef HAVE_AUTH
@@ -2568,7 +2586,7 @@ void tcp_request(int confd, time_t now, struct iovec *bigbuff,
       /* Do this by steam now we're not in the select() loop */
       check_log_writer(1); 
       
-      if (m == 0 && ede == EDE_UNSET)
+      if (!flags && m == 0 && ede == EDE_UNSET)
 	{
 	  struct server *master;
 	  int start;

src/helper.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -740,9 +740,11 @@ static unsigned char *grab_extradata_lua(unsigned char *buf, unsigned char *end,
   if (!buf || (buf == end))
     return NULL;
 
-  for (next = buf; *next != 0; next++)
+  for (next = buf; ; next++)
     if (next == end)
       return NULL;
+    else if (*next == 0)
+      break;
   
   if (next != buf)
     {

src/inotify.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
  
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -40,7 +40,7 @@ static char *inotify_buffer;
    points to, made absolute if relative.
    If path doesn't exist or is not a symlink, return NULL.
    Return value is malloc'ed */
-static char *my_readlink(char *path)
+static char *my_readlink(int errfd, char *path)
 {
   ssize_t rc, size = 64;
   char *buf;
@@ -59,7 +59,10 @@ static char *my_readlink(char *path)
 	      return NULL;
 	    }
 	  else
-	    die(_("cannot access path %s: %s"), path, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_LINK_ERR, errno, path);
+	      _exit(0);
+	    }
 	}
       else if (rc < size-1)
 	{
@@ -85,15 +88,18 @@ static char *my_readlink(char *path)
     }
 }
 
-void inotify_dnsmasq_init()
+void inotify_dnsmasq_init(int errfd)
 {
   struct resolvc *res;
   inotify_buffer = safe_malloc(INOTIFY_SZ);
   daemon->inotifyfd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
   
   if (daemon->inotifyfd == -1)
-    die(_("failed to create inotify: %s"), NULL, EC_MISC);
-
+    {
+      send_event(errfd, EVENT_INOTFY_ERR, errno, NULL);
+      _exit(0);
+    }
+  
   if (daemon->port == 0 || option_bool(OPT_NO_RESOLV))
     return;
   
@@ -105,10 +111,13 @@ void inotify_dnsmasq_init()
       strcpy(path, res->name);
 
       /* Follow symlinks until we reach a non-symlink, or a non-existent file. */
-      while ((new_path = my_readlink(path)))
+      while ((new_path = my_readlink(errfd, path)))
 	{
 	  if (links-- == 0)
-	    die(_("too many symlinks following %s"), res->name, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_TMSL_ERR, 0, res->name);
+	      _exit(0);
+	    }
 	  free(path);
 	  path = new_path;
 	}
@@ -124,12 +133,18 @@ void inotify_dnsmasq_init()
 	  *d = '/';
 	  
 	  if (res->wd == -1 && errno == ENOENT)
-	    die(_("directory %s for resolv-file is missing, cannot poll"), res->name, EC_MISC);
+	    {
+	      send_event(errfd, EVENT_RESOLV_ERR, 0, res->name);
+	      _exit(0);
+	    }
 	}	  
 	 
       if (res->wd == -1)
-	die(_("failed to create inotify for %s: %s"), res->name, EC_MISC);
-	
+	{
+	  send_event(errfd, EVENT_IFILE_ERR, errno, res->name);
+	  _exit(0);
+	}
+      	
     }
 }
 

src/ip6addr.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/lease.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -73,7 +73,9 @@ static int read_leases(time_t now, FILE *leasestream)
 		if (lease)
 		  {
 		    opt_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
-		    
+		    if (opt_len < 0)
+		      continue;
+
 		    if (strcmp(daemon->dhcp_buff3, "vendorclass") == 0)
 		      lease_set_vendorclass(lease, (unsigned char *)daemon->packet, opt_len);
 		    else if (strcmp(daemon->dhcp_buff3, "agent-info") == 0)
@@ -99,6 +101,8 @@ static int read_leases(time_t now, FILE *leasestream)
 	    
 	    
 	    hw_len = parse_hex(daemon->dhcp_buff2, (unsigned char *)daemon->dhcp_buff2, DHCP_CHADDR_MAX, NULL, &hw_type);
+	    if (hw_len < 0)
+	      hw_len = 0;
 	    /* For backwards compatibility, no explicit MAC address type means ether. */
 	    if (hw_type == 0 && hw_len != 0)
 	      hw_type = ARPHRD_ETHER; 
@@ -131,7 +135,11 @@ static int read_leases(time_t now, FILE *leasestream)
 	  die (_("too many stored leases"), NULL, EC_MISC);
 
 	if (strcmp(daemon->packet, "*") != 0)
-	  clid_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
+	  {
+	    clid_len = parse_hex(daemon->packet, (unsigned char *)daemon->packet, 255, NULL, NULL);
+	    if (clid_len < 0)
+	      clid_len = 0;
+	  }
 	
 	lease_set_hwaddr(lease, (unsigned char *)daemon->dhcp_buff2, (unsigned char *)daemon->packet, 
 			 hw_len, hw_type, clid_len, now, 0);

src/log.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -113,7 +113,7 @@ int log_start(struct passwd *ent_pw, int errfd)
       struct stat ls;
       if (getgid() == 0 && fstat(log_fd, &ls) == 0 && ls.st_gid == 0 &&
 	  (ls.st_mode & S_IWGRP) == 0)
-	(void)fchmod(log_fd, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
+	(void)fchmod(log_fd, ls.st_mode | S_IWGRP);
       if (fchown(log_fd, ent_pw->pw_uid, -1) != 0)
 	ret = errno;
     }

src/loop.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/metrics.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/metrics.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
    
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/netlink.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/network.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/nftset.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/option.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -4580,39 +4580,41 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	    only allowed for agent-options. */
 	 
 	 arg = comma;
-	 if ((comma = split(arg)))
+	 if (option  == 'U' && strstr(arg, "enterprise:") == arg)
 	   {
-	     if (option  != 'U' || strstr(arg, "enterprise:") != arg)
+	     comma = split(arg);
+	     new->enterprise = atoi(arg+11);
+	     arg = comma;
+	   }
+	 
+	 if (arg)
+	   {
+	     for (dig = 0, colon = 0, p = (unsigned char *)arg; *p; p++)
+	       if (isxdigit(*p))
+		 dig = 1;
+	       else if (*p == ':')
+		 colon = 1;
+	       else
+		 break;
+	     
+	     unhide_metas(arg);
+	     if (option == 'U' || option == 'j' || *p || !dig || !colon)
 	       {
-	         free(new->netid.net);
-	         ret_err_free(gen_err, new);
+		 new->len = strlen(arg);  
+		 new->data = opt_malloc(new->len);
+		 memcpy(new->data, arg, new->len);
 	       }
 	     else
-	       new->enterprise = atoi(arg+11);
+	       {
+		 new->len = parse_hex(comma, (unsigned char *)arg, strlen(arg), NULL, NULL);
+		 new->data = opt_malloc(new->len);
+		 memcpy(new->data, arg, new->len);
+	       }
 	   }
-	 else
-	   comma = arg;
-	 
-	 for (dig = 0, colon = 0, p = (unsigned char *)comma; *p; p++)
-	   if (isxdigit(*p))
-	     dig = 1;
-	   else if (*p == ':')
-	     colon = 1;
-	   else
-	     break;
-	 
-	 unhide_metas(comma);
-	 if (option == 'U' || option == 'j' || *p || !dig || !colon)
+	 else if (option != 'U' || new->enterprise == 0)
 	   {
-	     new->len = strlen(comma);  
-	     new->data = opt_malloc(new->len);
-	     memcpy(new->data, comma, new->len);
-	   }
-	 else
-	   {
-	     new->len = parse_hex(comma, (unsigned char *)comma, strlen(comma), NULL, NULL);
-	     new->data = opt_malloc(new->len);
-	     memcpy(new->data, comma, new->len);
+	     free(new->netid.net);
+	     ret_err_free(gen_err, new);
 	   }
 	 
 	 switch (option)
@@ -4635,7 +4637,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	   }
 	 new->next = daemon->dhcp_vendors;
 	 daemon->dhcp_vendors = new;
-
+	 
 	 break;
       }
       
@@ -4958,7 +4960,8 @@ err:
 	      arg = NULL; /* provoke error below */
 	  }
 	
-	if (!domain || !arg || !(new->name = canonicalise_opt(domain)))
+	if (!domain || !arg || !new->intr ||
+	    !(new->name = canonicalise_opt(domain)))
 	  ret_err(option == LOPT_DYNHOST ?
 		  _("bad dynamic host") : _("bad interface name"));
 	

src/outpacket.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/pattern.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/poll.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/radv-protocol.h

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/radv.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/rfc1035.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -317,7 +317,7 @@ unsigned char *skip_name(unsigned char *ansp, struct dns_header *header, size_t
       else if (label_type == 0x40)
 	{
 	  /* Extended label type */
-	  unsigned int count;
+	  unsigned int count, llen;
 	  
 	  if (!CHECK_LEN(header, ansp, plen, 2))
 	    return NULL;
@@ -328,9 +328,12 @@ unsigned char *skip_name(unsigned char *ansp, struct dns_header *header, size_t
 	  count = *(ansp++); /* Bits in bitstring */
 	  
 	  if (count == 0) /* count == 0 means 256 bits */
-	    ansp += 32;
+	    llen = 32;
 	  else
-	    ansp += ((count-1)>>3)+1;
+	    llen = ((count-1)>>3)+1;
+
+	  if (!ADD_RDLEN(header, ansp, plen, llen))
+	    return NULL;
 	}
       else
 	{ /* label type == 0 Bottom six bits is length */
@@ -1427,6 +1430,11 @@ int check_for_ignored_address(struct dns_header *header, size_t qlen)
   return check_bad_address(header, qlen, daemon->ignore_addr, NULL, NULL);
 }
 
+/* Nameoffset > 0 means that the name of the new record already exists at the given offset,
+   so use a "jump" to that.
+   Nameoffset == 0 means use the first variable argument as the name of the new record.
+   nameoffset < 0 means use the first variable argument as the start of the new record name,
+   then "jump" to -nameoffset to complete it. */
 int add_resource_record(struct dns_header *header, char *limit, int *truncp, int nameoffset, unsigned char **pp, 
 			unsigned long ttl, int *offset, unsigned short type, unsigned short class, char *format, ...)
 {

src/rfc2131.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -597,7 +597,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
       if (mess->file[0])
 	{
 	  memcpy(daemon->dhcp_buff2, mess->file, sizeof(mess->file));
-	  daemon->dhcp_buff2[sizeof(mess->file) + 1] = 0; /* ensure zero term. */
+	  daemon->dhcp_buff2[sizeof(mess->file)] = 0; /* ensure zero term. */
 	  id.net = (char *)daemon->dhcp_buff2;
 	  id.next = netid;
 	  netid = &id;
@@ -3248,7 +3248,7 @@ unsigned int relay_reply4(struct dhcp_packet *mess, size_t sz, char *arrival_int
 
 	      /* delete agent info before return RFC 3046 para 2.1 */
 	      *opt = OPTION_END;
-	      memset(opt + 1, 0, option_len(opt) + 2);
+	      memset(opt + 1, 0, option_len(opt) + 1);
 	    }
 	}
       else if (mess->giaddr.s_addr == relay->local.addr4.s_addr)

src/rfc3315.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -24,7 +24,7 @@ struct state {
   int clid_len, ia_type, interface, hostname_auth, lease_allocate;
   char *client_hostname, *hostname, *domain, *send_domain;
   struct dhcp_context *context;
-  struct in6_addr *link_address, *fallback, *ll_addr, *ula_addr;
+  struct in6_addr *relay_address, *fallback, *ll_addr, *ula_addr;
   unsigned int xid, fqdn_flags, iaid;
   char *iface_name;
   void *packet_options, *end;
@@ -34,13 +34,13 @@ struct state {
 };
 
 static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t sz, 
-			     struct in6_addr *client_addr, time_t now);
+			     struct in6_addr *client_addr, struct in6_addr *link_address, time_t now);
 static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbuff, size_t sz, time_t now);
 static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_opts);
 static void log6_packet(struct state *state, char *type, struct in6_addr *addr, char *string);
 static void log6_quiet(struct state *state, char *type, struct in6_addr *addr, char *string);
-static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, unsigned int minsize);
-static void *opt6_next(uint8_t *opts, uint8_t *end);
+static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, int minsize);
+static void *opt6_first(uint8_t *opt, uint8_t *end);
 static unsigned int opt6_uint(unsigned char *opt, int offset, int size);
 static void get_context_tag(struct state *state, struct dhcp_context *context);
 static int check_ia(struct state *state, void *opt, void **endp, void **ia_option);
@@ -62,6 +62,7 @@ static void calculate_times(struct dhcp_context *context, unsigned int *min_time
 #define opt6_len(opt) ((int)(opt6_uint(opt, -2, 2)))
 #define opt6_type(opt) (opt6_uint(opt, -4, 2))
 #define opt6_ptr(opt, i) ((void *)&(((uint8_t *)(opt))[4+(i)]))
+#define opt6_next(opt, end) (opt6_first(opt6_ptr((opt), opt6_len((opt))), (end)))
 
 #define opt6_user_vendor_ptr(opt, i) ((void *)&(((uint8_t *)(opt))[2+(i)]))
 #define opt6_user_vendor_len(opt) ((int)(opt6_uint(opt, -4, 2)))
@@ -98,9 +99,8 @@ unsigned short dhcp6_reply(struct dhcp_context *context, int multicast_dest, int
   state.ula_addr = ula_addr;
   state.mac_len = 0;
   state.tags = NULL;
-  state.link_address = NULL;
-
-  if (dhcp6_maybe_relay(&state, daemon->dhcp_packet.iov_base, sz, client_addr, now))
+  
+  if (dhcp6_maybe_relay(&state, daemon->dhcp_packet.iov_base, sz, client_addr, NULL, now))
     return msg_type == DHCP6RELAYFORW ? DHCPV6_SERVER_PORT : DHCPV6_CLIENT_PORT;
 
   return 0;
@@ -108,15 +108,22 @@ unsigned short dhcp6_reply(struct dhcp_context *context, int multicast_dest, int
 
 /* This cost me blood to write, it will probably cost you blood to understand - srk. */
 static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t sz, 
-			     struct in6_addr *client_addr, time_t now)
+			     struct in6_addr *client_addr, struct in6_addr *link_address, time_t now)
 {
   uint8_t *end = inbuff + sz;
   uint8_t *opts = inbuff + 34;
-  int msg_type = *inbuff;
+  int msg_type;
   unsigned char *outmsgtypep;
   uint8_t *opt;
   struct dhcp_vendor *vendor;
 
+  /* must have at least msg_type+trans_id
+     which is               1   +   3      = 4 */
+  if (sz < 4)
+    return 0;
+
+  msg_type = *inbuff;
+
   /* if not an encapsulated relayed message, just do the stuff */
   if (msg_type != DHCP6RELAYFORW)
     {
@@ -128,7 +135,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
       link_address == NULL means there's no relay in use, so we try and find the client's 
       MAC address from the local ND cache. */
       
-      if (!state->link_address)
+      if (!link_address)
 	get_client_mac(client_addr, state->interface, state->mac, &state->mac_len, &state->mac_type, now);
       else
 	{
@@ -136,9 +143,9 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  struct shared_network *share = NULL;
 	  state->context = NULL;
 
-	  if (!IN6_IS_ADDR_LOOPBACK(state->link_address) &&
-	      !IN6_IS_ADDR_LINKLOCAL(state->link_address) &&
-	      !IN6_IS_ADDR_MULTICAST(state->link_address))
+	  if (!IN6_IS_ADDR_LOOPBACK(link_address) &&
+	      !IN6_IS_ADDR_LINKLOCAL(link_address) &&
+	      !IN6_IS_ADDR_MULTICAST(link_address))
 	    for (c = daemon->dhcp6; c; c = c->next)
 	      {
 		for (share = daemon->shared_networks; share; share = share->next)
@@ -147,7 +154,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 		      continue;
 		    
 		    if (share->if_index != 0 ||
-			!IN6_ARE_ADDR_EQUAL(state->link_address, &share->match_addr6))
+			!IN6_ARE_ADDR_EQUAL(link_address, &share->match_addr6))
 		      continue;
 		    
 		    if ((c->flags & CONTEXT_DHCP) &&
@@ -160,8 +167,8 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 		if (share ||
 		    ((c->flags & CONTEXT_DHCP) &&
 		     !(c->flags & (CONTEXT_TEMPLATE | CONTEXT_OLD)) &&
-		     is_same_net6(state->link_address, &c->start6, c->prefix) &&
-		     is_same_net6(state->link_address, &c->end6, c->prefix)))
+		     is_same_net6(link_address, &c->start6, c->prefix) &&
+		     is_same_net6(link_address, &c->end6, c->prefix)))
 		  {
 		    c->preferred = c->valid = 0xffffffff;
 		    c->current = state->context;
@@ -171,7 +178,7 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  
 	  if (!state->context)
 	    {
-	      inet_ntop(AF_INET6, state->link_address, daemon->addrbuff, ADDRSTRLEN); 
+	      inet_ntop(AF_INET6, link_address, daemon->addrbuff, ADDRSTRLEN); 
 	      my_syslog(MS_DHCP | LOG_WARNING, 
 			_("no address range available for DHCPv6 request from relay at %s"),
 			daemon->addrbuff);
@@ -186,6 +193,8 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	  return 0;
 	}
 
+      state->relay_address = link_address;
+
       return dhcp6_no_relay(state, msg_type, inbuff, sz, now);
     }
 
@@ -233,11 +242,8 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
       memcpy(&state->mac[0], opt6_ptr(opt, 2), state->mac_len);
     }
   
-  for (opt = opts; opt; opt = opt6_next(opt, end))
+  for (opt = opt6_first(opts, end); opt; opt = opt6_next(opt, end))
     {
-      if ((uint8_t *)opt6_ptr(opt, 0) + opt6_len(opt) > end)
-        return 0;
-     
       /* Don't copy MAC address into reply. */
       if (opt6_type(opt) != OPTION6_CLIENT_MAC)
 	{
@@ -248,11 +254,12 @@ static int dhcp6_maybe_relay(struct state *state, unsigned char *inbuff, size_t
 	      /* the packet data is unaligned, copy to aligned storage */
 	      memcpy(&align, inbuff + 2, IN6ADDRSZ); 
 
-
-	      /* RFC6221 para 4 */
-	      if (!IN6_IS_ADDR_UNSPECIFIED(&align))
-		state->link_address = &align;
-	      if (!dhcp6_maybe_relay(state, opt6_ptr(opt, 0), opt6_len(opt), client_addr, now))
+	      /* RFC6221 para 4 says if link_address in encapulation
+		 is zero, ignore it, and, by implication, use the link
+		 address of any enclosing encapsulation or, failing that
+		 of the arrival interface on the the server. */
+	      if (!dhcp6_maybe_relay(state, opt6_ptr(opt, 0), opt6_len(opt), client_addr,
+				     IN6_IS_ADDR_UNSPECIFIED(&align) ? link_address : &align, now))
 		return 0;
 	    }
 	  else
@@ -290,7 +297,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
   state->hostname = NULL;
   state->client_hostname = NULL;
   state->fqdn_flags = 0x01; /* default to send if we receive no FQDN option */
-
+  
   /* set tag with name == interface */
   iface_id.net = state->iface_name;
   iface_id.next = state->tags;
@@ -387,13 +394,26 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	      if (opt6_len(opt) < 4)
 		continue;
 	      
-	      if (vendor->enterprise != opt6_uint(opt, 0, 4))
+	      if (vendor->enterprise != 0 && vendor->enterprise != opt6_uint(opt, 0, 4))
 		continue;
-	    
+
+	      /* matching enterprise, no string match. */
+	      if (vendor->enterprise != 0 && vendor->len == 0)
+		{
+		  vendor->netid.next = state->tags;
+		  state->tags = &vendor->netid;
+		  break;
+		}
+	      
 	      offset = 4;
+
+	      /* If we're going to search the strings below, there must be at least one empty string to search
+		 I think a vendor_class option with just the enterprise number is valid. */
+	      if (opt6_len(opt) < 6)
+		continue;
 	    }
- 
-	  /* Note that format if user/vendor classes is different to DHCP options - no option types. */
+
+       	  /* Note that format if user/vendor classes is different to DHCP options - no option types. */
 	  for (enc_opt = opt6_ptr(opt, offset); enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
 	    for (i = 0; i <= (opt6_user_vendor_len(enc_opt) - vendor->len); i++)
 	      if (memcmp(vendor->data, opt6_user_vendor_ptr(enc_opt, i), vendor->len) == 0)
@@ -657,7 +677,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	for (c = state->context; c; c = c->current)
 	  c->flags &= ~CONTEXT_CONF_USED;
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {   
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -821,7 +841,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	if (ignore)
 	  return 0;
 	
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {   
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -932,7 +952,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, msg_type == DHCP6RENEW ? "DHCPRENEW" : "DHCPREBIND", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    unsigned int min_time = 0xffffffff;
@@ -1067,7 +1087,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, "DHCPCONFIRM", NULL, NULL);
 	
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    
@@ -1143,7 +1163,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 
 	log6_quiet(state, "DHCPRELEASE", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    int made_ia = 0;
@@ -1208,7 +1228,7 @@ static int dhcp6_no_relay(struct state *state, int msg_type, unsigned char *inbu
 	
 	log6_quiet(state, "DHCPDECLINE", NULL, NULL);
 
-	for (opt = state->packet_options; opt; opt = opt6_next(opt, state->end))
+	for (opt = opt6_first(state->packet_options, state->end); opt; opt = opt6_next(opt, state->end))
 	  {
 	    void *ia_option, *ia_end;
 	    int made_ia = 0;
@@ -1580,10 +1600,7 @@ static int check_ia(struct state *state, void *opt, void **endp, void **ia_optio
 {
   *ia_option = NULL;
 
-  /* must be a minimal option to check without stepping outside received packet. */
-  if (opt6_ptr(opt, 4) > state->end)
-    return 0;
-  
+  /* callee ensures packet is long enough for opt6_len(opt) to be valid and believe-able. */
   state->ia_type = opt6_type(opt);
   
   if (state->ia_type != OPTION6_IA_NA && state->ia_type != OPTION6_IA_TA)
@@ -1595,10 +1612,7 @@ static int check_ia(struct state *state, void *opt, void **endp, void **ia_optio
   if (state->ia_type == OPTION6_IA_TA && opt6_len(opt) < 4)
     return 0;
   
-  /* Check we don't overflow the received packet. */
-  if ((*endp = opt6_ptr(opt, opt6_len(opt))) > state->end)
-    return 0;
-  
+  *endp = opt6_ptr(opt, opt6_len(opt));
   state->iaid = opt6_uint(opt, 0, 4);
   *ia_option = opt6_find(opt6_ptr(opt, state->ia_type == OPTION6_IA_NA ? 12 : 4), *endp, OPTION6_IAADDR, 24);
 
@@ -1913,10 +1927,10 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 	      lease_add_extradata(lease, (unsigned char *)daemon->dhcp_buff2, strlen(daemon->dhcp_buff2), 0);
 	      
 	      if (opt6_len(opt) >= 6) 
-		for (enc_opt = opt6_ptr(opt, 4); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
+		for (enc_opt = opt6_ptr(opt, 4); enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
 		  {
 		    lease->vendorclass_count++;
-		    lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
+		    lease_add_extradata(lease, opt6_user_vendor_ptr(enc_opt, 0), opt6_user_vendor_len(enc_opt), 0);
 		  }
 	    }
 	  
@@ -1965,16 +1979,16 @@ static void update_leases(struct state *state, struct dhcp_context *context, str
 		}
 	    }
 	  
-	  if (state->link_address)
-	    inet_ntop(AF_INET6, state->link_address, daemon->addrbuff, ADDRSTRLEN);
+	  if (state->relay_address)
+	    inet_ntop(AF_INET6, state->relay_address, daemon->addrbuff, ADDRSTRLEN);
 	  
-	  lease_add_extradata(lease, (unsigned char *)daemon->addrbuff, state->link_address ? strlen(daemon->addrbuff) : 0, 0);
+	  lease_add_extradata(lease, (unsigned char *)daemon->addrbuff, state->relay_address ? strlen(daemon->addrbuff) : 0, 0);
 	  
 	  if ((opt = opt6_find(state->packet_options, state->end, OPTION6_USER_CLASS, 2)))
 	    {
 	      void *enc_opt, *enc_end = opt6_ptr(opt, opt6_len(opt));
-	      for (enc_opt = opt6_ptr(opt, 0); enc_opt; enc_opt = opt6_next(enc_opt, enc_end))
-		lease_add_extradata(lease, opt6_ptr(enc_opt, 0), opt6_len(enc_opt), 0);
+	      for (enc_opt = opt6_ptr(opt, 0); enc_opt; enc_opt = opt6_user_vendor_next(enc_opt, enc_end))
+		lease_add_extradata(lease, opt6_user_vendor_ptr(enc_opt, 0), opt6_user_vendor_len(enc_opt), 0);
 	    }
 	}
 #endif	
@@ -1989,10 +2003,10 @@ static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_op
   void *opt;
   char *desc = nest ? "nest" : "sent";
   
-  if (!option_bool(OPT_LOG_OPTS) || start_opts == end_opts)
+  if (!option_bool(OPT_LOG_OPTS))
     return;
   
-  for (opt = start_opts; opt; opt = opt6_next(opt, end_opts))
+  for (opt = opt6_first(start_opts, end_opts); opt; opt = opt6_next(opt, end_opts))
     {
       int type = opt6_type(opt);
       void *ia_options = NULL;
@@ -2025,9 +2039,15 @@ static void log6_opts(int nest, unsigned int xid, void *start_opts, void *end_op
 	}
       else if (type == OPTION6_STATUS_CODE)
 	{
-	  int len = sprintf(daemon->namebuff, "%u ", opt6_uint(opt, 0, 2));
-	  memcpy(daemon->namebuff + len, opt6_ptr(opt, 2), opt6_len(opt)-2);
-	  daemon->namebuff[len + opt6_len(opt) - 2] = 0;
+	  if (opt6_len(opt) >= 2)
+	    {
+	      int slen = opt6_len(opt) - 2;
+	      int len = sprintf(daemon->namebuff, "%u ", opt6_uint(opt, 0, 2));
+	      if (slen > (MAXDNAME * 2) - len - 1)
+		slen = (MAXDNAME * 2) - len - 1;
+	      memcpy(daemon->namebuff + len, opt6_ptr(opt, 2), slen);
+	      daemon->namebuff[len + slen] = 0;
+	    }
 	  optname = "status";
 	}
       else
@@ -2086,49 +2106,31 @@ static void log6_packet(struct state *state, char *type, struct in6_addr *addr,
 	      string ? string : "");
 }
 
-static void *opt6_find (uint8_t *opts, uint8_t *end, unsigned int search, unsigned int minsize)
+static void *opt6_find(uint8_t *opts, uint8_t *end, unsigned int search, int minsize)
 {
-  u16 opt, opt_len;
-  void *start;
-  
-  if (!opts)
-    return NULL;
-    
-  while (1)
-    {
-      if (end - opts < 4) 
-	return NULL;
-      
-      start = opts;
-      GETSHORT(opt, opts);
-      GETSHORT(opt_len, opts);
-      
-      if (opt_len > (end - opts))
-	return NULL;
-      
-      if (opt == search && (opt_len >= minsize))
-	return start;
-      
-      opts += opt_len;
-    }
+  for (opts = opt6_first(opts, end); opts; opts = opt6_next(opts, end))
+    if (opt6_type(opts) == search && opt6_len(opts) >= minsize)
+      return opts;
+
+  return NULL;
 }
 
-static void *opt6_next(uint8_t *opts, uint8_t *end)
+static void *opt6_first(uint8_t *opt, uint8_t *end)
 {
-  u16 opt_len;
-  
-  if (end - opts < 4) 
+  if (!opt)
     return NULL;
-  
-  opts += 2;
-  GETSHORT(opt_len, opts);
-  
-  if (opt_len >= (end - opts))
-    return NULL;
-  
-  return opts + opt_len;
-}
 
+  /* make sure we have option number and length. */
+  if ((uint8_t *)opt6_ptr(opt, 0) > end)
+    return NULL;
+
+  /* make sure we have bytes promised by length. */
+  if ((uint8_t *)opt6_ptr(opt, opt6_len(opt)) > end)
+    return NULL;
+
+  return opt;
+}
+  
 static unsigned int opt6_uint(unsigned char *opt, int offset, int size)
 {
   /* this worries about unaligned data and byte order */

src/rrfilter.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/slaac.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/tftp.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -545,8 +545,13 @@ static struct tftp_file *check_tftp_fileperm(char *packet, ssize_t *len, char *p
   int fd = -1;
 
   /* trick to ban moving out of the subtree */
-  if (prefix && strstr(namebuff, "/../"))
-    goto perm;
+  if (prefix)
+    {
+      char *suspect = strstr(namebuff, "/..");
+
+      if (suspect && (suspect[3] == '/' || suspect[3] == 0))
+        goto perm;
+    }
   
   if ((fd = open(namebuff, O_RDONLY)) == -1)
     {

src/ubus.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

src/util.c

@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2025 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -105,8 +105,6 @@ u32 rand32(void)
 
 u64 rand64(void)
 {
-  static int outleft = 0;
-
   if (outleft < 2)
     {
       if (!++in[0]) if (!++in[1]) if (!++in[2]) ++in[3];
@@ -266,6 +264,10 @@ char *canonicalise(char *in, int *nomem)
 	  
 	  return NULL;
 	}
+
+      /* IDN library doesnt call our malloc wrapper, so log this by steam */
+      if (ret)
+	malloc_log(ret, strlen(ret)+1);
       
       return ret;
     }
@@ -323,13 +325,15 @@ void *safe_malloc(size_t size)
 }
 
 /* Ensure limited size string is always terminated.
- * Can be replaced by (void)strlcpy() on some platforms */
+   Can be replaced by (void)strlcpy() on some platforms.
+   src may be NULL in which case we return an empty string. */
 void safe_strncpy(char *dest, const char *src, size_t size)
 {
   if (size != 0)
     {
-      dest[size-1] = '\0';
-      strncpy(dest, src, size-1);
+      dest[0] = dest[size-1] = '\0';
+      if (src)
+	strncpy(dest, src, size-1);
     }
 }
 
@@ -575,6 +579,7 @@ void prettyprint_time(char *buf, unsigned int t)
   else
     {
       unsigned int x, p = 0;
+      buf[0] = '\0';
        if ((x = t/86400))
 	p += sprintf(&buf[p], "%ud", x);
        if ((x = (t/3600)%24))
@@ -985,7 +990,7 @@ int expand_workspace_real(const char *func, unsigned int line, unsigned char ***
   if (!(p = whine_realloc_real("expand_workspace", func, line, *wkspc, new * sizeof(unsigned char *))))
     return 0;
 
-  memset(p+old, 0, new-old);
+  memset(p+old, 0, (new-old) * sizeof(unsigned char *));
   
   *wkspc = p;
   *szp = new;
@@ -993,6 +998,12 @@ int expand_workspace_real(const char *func, unsigned int line, unsigned char ***
   return 1;
 }
 
+void malloc_log_real(const char *func, unsigned int line, void *mem, size_t size)
+{
+  if (mem && daemon->log_malloc)
+    my_syslog(LOG_INFO, _("malloc: %s:%u %zu bytes at %x"), func, line, size, hash_ptr(mem));
+}
+
 #undef free
 void free_real(const char *func, unsigned int line, void *ptr)
 {