Index: head/sys/netpfil/pf/pf.c
===================================================================
--- head/sys/netpfil/pf/pf.c
+++ head/sys/netpfil/pf/pf.c
@@ -369,11 +369,14 @@
 u_long	pf_srchashmask;
 static u_long	pf_hashsize;
 static u_long	pf_srchashsize;
+u_long	pf_ioctl_maxcount = 65535;
 
 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
     &pf_hashsize, 0, "Size of pf(4) states hashtable");
 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
     &pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
+SYSCTL_ULONG(_net_pf, OID_AUTO, request_maxcount, CTLFLAG_RDTUN,
+    &pf_ioctl_maxcount, 0, "Maximum number of tables, addresses, ... in a single ioctl() call");
 
 VNET_DEFINE(void *, pf_swi_cookie);
 
Index: head/sys/netpfil/pf/pf_ioctl.c
===================================================================
--- head/sys/netpfil/pf/pf_ioctl.c
+++ head/sys/netpfil/pf/pf_ioctl.c
@@ -89,8 +89,6 @@
 #include <net/altq/altq.h>
 #endif
 
-#define PF_TABLES_MAX_REQUEST   65535 /* Maximum tables per request. */
-
 static struct pf_pool	*pf_get_pool(char *, u_int32_t, u_int8_t, u_int32_t,
 			    u_int8_t, u_int8_t, u_int8_t);
 
@@ -218,6 +216,8 @@
 /* pflog */
 pflog_packet_t			*pflog_packet_ptr = NULL;
 
+extern u_long	pf_ioctl_maxcount;
+
 static void
 pfattach_vnet(void)
 {
@@ -2533,7 +2533,8 @@
 			break;
 		}
 
-		if (io->pfrio_size < 0 || io->pfrio_size > PF_TABLES_MAX_REQUEST) {
+		if (io->pfrio_size < 0 || io->pfrio_size > pf_ioctl_maxcount ||
+		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_table))) {
 			error = ENOMEM;
 			break;
 		}
@@ -2564,7 +2565,8 @@
 			break;
 		}
 
-		if (io->pfrio_size < 0 || io->pfrio_size > PF_TABLES_MAX_REQUEST) {
+		if (io->pfrio_size < 0 || io->pfrio_size > pf_ioctl_maxcount ||
+		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_table))) {
 			error = ENOMEM;
 			break;
 		}
@@ -2741,6 +2743,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -2778,6 +2781,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -2819,7 +2823,8 @@
 			break;
 		}
 		count = max(io->pfrio_size, io->pfrio_size2);
-		if (WOULD_OVERFLOW(count, sizeof(struct pfr_addr))) {
+		if (count > pf_ioctl_maxcount ||
+		    WOULD_OVERFLOW(count, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
 		}
@@ -2857,6 +2862,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -2888,6 +2894,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_astats))) {
 			error = EINVAL;
 			break;
@@ -2919,6 +2926,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -2956,6 +2964,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -2993,6 +3002,7 @@
 			break;
 		}
 		if (io->pfrio_size < 0 ||
+		    io->pfrio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfrio_size, sizeof(struct pfr_addr))) {
 			error = EINVAL;
 			break;
@@ -3045,6 +3055,7 @@
 			break;
 		}
 		if (io->size < 0 ||
+		    io->size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->size, sizeof(struct pfioc_trans_e))) {
 			error = EINVAL;
 			break;
@@ -3121,6 +3132,7 @@
 			break;
 		}
 		if (io->size < 0 ||
+		    io->size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->size, sizeof(struct pfioc_trans_e))) {
 			error = EINVAL;
 			break;
@@ -3198,6 +3210,7 @@
 		}
 
 		if (io->size < 0 ||
+		    io->size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->size, sizeof(struct pfioc_trans_e))) {
 			error = EINVAL;
 			break;
@@ -3410,6 +3423,7 @@
 		}
 
 		if (io->pfiio_size < 0 ||
+		    io->pfiio_size > pf_ioctl_maxcount ||
 		    WOULD_OVERFLOW(io->pfiio_size, sizeof(struct pfi_kif))) {
 			error = EINVAL;
 			break;