Test for overflowing platform FD_SET size.

diff --git a/src/dbus.c b/src/dbus.c
index 3d686e86f41eb145ac701542544cae41841d512f..1384ccffff18210b0dcd971401cd16590b8fe831 100644 (file)
--- a/src/dbus.c
+++ b/src/dbus.c
@@ -760,15 +760,13 @@ void set_dbus_listeners(int *maxfdp,
        unsigned int flags = dbus_watch_get_flags(w->watch);
        int fd = dbus_watch_get_unix_fd(w->watch);
        
-       bump_maxfd(fd, maxfdp);
-       
        if (flags & DBUS_WATCH_READABLE)
-         FD_SET(fd, rset);
+         bump_maxfd(rset, fd, maxfdp);
        
        if (flags & DBUS_WATCH_WRITABLE)
-         FD_SET(fd, wset);
+         bump_maxfd(wset, fd, maxfdp);
        
-       FD_SET(fd, eset);
+       bump_maxfd(eset, fd, maxfdp);
       }
 }
 

diff --git a/src/dnsmasq.c b/src/dnsmasq.c
index 5fb4281a39b83aafe1be0bcb58e27e212738c038..fd24f63df9ec350ea19f2bfdeeb143df0a16bc5c 100644 (file)
--- a/src/dnsmasq.c
+++ b/src/dnsmasq.c
@@ -902,48 +902,32 @@ int main (int argc, char **argv)
 #ifdef HAVE_DHCP
       if (daemon->dhcp || daemon->relay4)
        {
-         FD_SET(daemon->dhcpfd, &rset);
-         bump_maxfd(daemon->dhcpfd, &maxfd);
+         bump_maxfd(&rset, daemon->dhcpfd, &maxfd);
          if (daemon->pxefd != -1)
-           {
-             FD_SET(daemon->pxefd, &rset);
-             bump_maxfd(daemon->pxefd, &maxfd);
-           }
+           bump_maxfd(&rset, daemon->pxefd, &maxfd);
        }
 #endif
 
 #ifdef HAVE_DHCP6
       if (daemon->doing_dhcp6 || daemon->relay6)
-       {
-         FD_SET(daemon->dhcp6fd, &rset);
-         bump_maxfd(daemon->dhcp6fd, &maxfd);
-       }
-
+       bump_maxfd(&rset, daemon->dhcp6fd, &maxfd);
+       
       if (daemon->doing_ra)
-       {
-         FD_SET(daemon->icmp6fd, &rset);
-         bump_maxfd(daemon->icmp6fd, &maxfd); 
-       }
+       bump_maxfd(&rset, daemon->icmp6fd, &maxfd); 
 #endif
     
 #ifdef HAVE_INOTIFY
       if (daemon->inotifyfd != -1)
-       {
-         FD_SET(daemon->inotifyfd, &rset);
-         bump_maxfd(daemon->inotifyfd, &maxfd);
-       }
+       bump_maxfd(&rset, daemon->inotifyfd, &maxfd);
 #endif
 
 #if defined(HAVE_LINUX_NETWORK)
-      FD_SET(daemon->netlinkfd, &rset);
-      bump_maxfd(daemon->netlinkfd, &maxfd);
+      bump_maxfd(&rset, daemon->netlinkfd, &maxfd);
 #elif defined(HAVE_BSD_NETWORK)
-      FD_SET(daemon->routefd, &rset);
-      bump_maxfd(daemon->routefd, &maxfd);
+      bump_maxfd(&rset, daemon->routefd, &maxfd);
 #endif
       
-      FD_SET(piperead, &rset);
-      bump_maxfd(piperead, &maxfd);
+      bump_maxfd(&rset, piperead, &maxfd);
 
 #ifdef HAVE_DHCP
 #  ifdef HAVE_SCRIPT
@@ -954,10 +938,7 @@ int main (int argc, char **argv)
 #    endif
 
       if (!helper_buf_empty())
-       {
-         FD_SET(daemon->helperfd, &wset);
-         bump_maxfd(daemon->helperfd, &maxfd);
-       }
+       bump_maxfd(&wset, daemon->helperfd, &maxfd);
 #  else
       /* need this for other side-effects */
       while (do_script_run(now));
@@ -1482,8 +1463,7 @@ static int set_dns_listeners(time_t now, fd_set *set, int *maxfdp)
   for (transfer = daemon->tftp_trans; transfer; transfer = transfer->next)
     {
       tftp++;
-      FD_SET(transfer->sockfd, set);
-      bump_maxfd(transfer->sockfd, maxfdp);
+      bump_maxfd(set, transfer->sockfd, maxfdp);
     }
 #endif
   
@@ -1492,45 +1472,32 @@ static int set_dns_listeners(time_t now, fd_set *set, int *maxfdp)
     get_new_frec(now, &wait, 0);
   
   for (serverfdp = daemon->sfds; serverfdp; serverfdp = serverfdp->next)
-    {
-      FD_SET(serverfdp->fd, set);
-      bump_maxfd(serverfdp->fd, maxfdp);
-    }
-
+    bump_maxfd(set, serverfdp->fd, maxfdp);
+    
   if (daemon->port != 0 && !daemon->osport)
     for (i = 0; i < RANDOM_SOCKS; i++)
       if (daemon->randomsocks[i].refcount != 0)
-       {
-         FD_SET(daemon->randomsocks[i].fd, set);
-         bump_maxfd(daemon->randomsocks[i].fd, maxfdp);
-       }
-  
+       bump_maxfd(set, daemon->randomsocks[i].fd, maxfdp);
+         
   for (listener = daemon->listeners; listener; listener = listener->next)
     {
       /* only listen for queries if we have resources */
       if (listener->fd != -1 && wait == 0)
-       {
-         FD_SET(listener->fd, set);
-         bump_maxfd(listener->fd, maxfdp);
-       }
-
+       bump_maxfd(set, listener->fd, maxfdp);
+       
       /* death of a child goes through the select loop, so
         we don't need to explicitly arrange to wake up here */
       if  (listener->tcpfd != -1)
        for (i = 0; i < MAX_PROCS; i++)
          if (daemon->tcp_pids[i] == 0)
            {
-             FD_SET(listener->tcpfd, set);
-             bump_maxfd(listener->tcpfd, maxfdp);
+             bump_maxfd(set, listener->tcpfd, maxfdp);
              break;
            }
 
 #ifdef HAVE_TFTP
       if (tftp <= daemon->tftp_max && listener->tftpfd != -1)
-       {
-         FD_SET(listener->tftpfd, set);
-         bump_maxfd(listener->tftpfd, maxfdp);
-       }
+       bump_maxfd(set, listener->tftpfd, maxfdp);
 #endif
 
     }
@@ -1822,10 +1789,7 @@ int icmp_ping(struct in_addr addr)
       
 #ifdef HAVE_DHCP6
       if (daemon->doing_ra)
-       {
-         FD_SET(daemon->icmp6fd, &rset);
-         bump_maxfd(daemon->icmp6fd, &maxfd); 
-       }
+       bump_maxfd(&rset, daemon->icmp6fd, &maxfd); 
 #endif
       
       rc = select(maxfd+1, &rset, &wset, NULL, &tv);

diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index 8d005d732e72a1768fc0a2eec30475ad20c16cca..2be27f190446d30ea7ef015903c9ac240ea03e3a 100644 (file)
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -1191,7 +1191,7 @@ int memcmp_masked(unsigned char *a, unsigned char *b, int len,
                  unsigned int mask);
 int expand_buf(struct iovec *iov, size_t size);
 char *print_mac(char *buff, unsigned char *mac, int len);
-void bump_maxfd(int fd, int *max);
+void bump_maxfd(fd_set *set, int fd, int *max);
 int read_write(int fd, unsigned char *packet, int size, int rw);
 
 int wildcard_match(const char* wildcard, const char* match);

diff --git a/src/log.c b/src/log.c
index a5ac605c7c5db527576ddb6544f6994cfed734e5..8e2f9303ead933ae502ed00f49cbae7d142e5546 100644 (file)
--- a/src/log.c
+++ b/src/log.c
@@ -424,10 +424,7 @@ void my_syslog(int priority, const char *format, ...)
 void set_log_writer(fd_set *set, int *maxfdp)
 {
   if (entries && log_fd != -1 && connection_good)
-    {
-      FD_SET(log_fd, set);
-      bump_maxfd(log_fd, maxfdp);
-    }
+    bump_maxfd(set, log_fd, maxfdp);
 }
 
 void check_log_writer(fd_set *set)

diff --git a/src/util.c b/src/util.c
index 9299703c6d30aac851980b245dc95a8394323598..59ea5185f9fb585f62eac35769ab87703f7407fa 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -570,10 +570,23 @@ char *print_mac(char *buff, unsigned char *mac, int len)
   return buff;
 }
 
-void bump_maxfd(int fd, int *max)
+void bump_maxfd(fd_set *set, int fd, int *max)
 {
-  if (fd > *max)
-    *max = fd;
+#ifdef FD_SETSIZE
+  if (fd >= FD_SETSIZE)
+    {
+      static int logged = 0;
+      if (!logged)
+       my_syslog(LOG_ERR, _("File descriptor overflows FS_SET"));
+      logged = 1;
+    }
+  else
+ #endif
+    {
+      FD_SET(fd, set);
+      if (fd > *max)
+       *max = fd;
+    }
 }
 
 /* rc is return from sendto and friends.