security/wpa_supplicant-devel: Fix uninitialized packet pointer on error

The packet pointer (called packet) will remain uninitialized when
pcap_next_ex() returns an error. This occurs when the wlan
interface is shut down using ifconfig destroy. Adding a NULL
assignment to packet duplicates what pcap_next() does.

The reason we use pcap_next_ex() in this instance is because with
pacp_next() when we receive a null pointer if there was an error
or if no packets were read. With pcap_next_ex() we can differentiate
between an error and legitimately no packets were received.

PR:             270649, 273696
Obtained from:	src 953efa5b200f
Reported by:    Robert Morris <rtm@lcs.mit.edu>
MFH:		2023Q3

security/wpa_supplicant-devel/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	wpa_supplicant
 PORTVERSION=	${COMMIT_DATE}
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	security net
 PKGNAMESUFFIX=	-devel
 

security/wpa_supplicant-devel/files/patch-src_l2__packet_l2__packet__freebsd.c

@@ -1,5 +1,5 @@
 --- src/l2_packet/l2_packet_freebsd.c.orig	2023-09-05 10:38:47.000000000 -0700
-+++ src/l2_packet/l2_packet_freebsd.c	2023-09-11 22:06:24.154851000 -0700
++++ src/l2_packet/l2_packet_freebsd.c	2023-09-11 22:12:22.076149000 -0700
 @@ -8,7 +8,10 @@
   */
 
@@ -12,15 +12,37 @@
  #include <net/bpf.h>
  #endif /* __APPLE__ */
  #include <pcap.h>
-@@ -82,7 +85,10 @@
+@@ -76,24 +79,28 @@
+ {
+ 	struct l2_packet_data *l2 = eloop_ctx;
+ 	pcap_t *pcap = sock_ctx;
+-	struct pcap_pkthdr hdr;
++	struct pcap_pkthdr *hdr;
+ 	const u_char *packet;
+ 	struct l2_ethhdr *ethhdr;
  	unsigned char *buf;
  	size_t len;
 
 -	packet = pcap_next(pcap, &hdr);
 +	if (pcap_next_ex(pcap, &hdr, &packet) == -1) {
 +		wpa_printf(MSG_ERROR, "Error reading packet, has device disappeared?");
++		packet = NULL;
 +		eloop_terminate();
 +	}
 
- 	if (!l2->rx_callback || !packet || hdr.caplen < sizeof(*ethhdr))
+-	if (!l2->rx_callback || !packet || hdr.caplen < sizeof(*ethhdr))
++	if (!l2->rx_callback || !packet || hdr->caplen < sizeof(*ethhdr))
  		return;
+
+ 	ethhdr = (struct l2_ethhdr *) packet;
+ 	if (l2->l2_hdr) {
+ 		buf = (unsigned char *) ethhdr;
+-		len = hdr.caplen;
++		len = hdr->caplen;
+ 	} else {
+ 		buf = (unsigned char *) (ethhdr + 1);
+-		len = hdr.caplen - sizeof(*ethhdr);
++		len = hdr->caplen - sizeof(*ethhdr);
+ 	}
+ 	l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len);
+ }