If we can't allocate a DLT_ list, fail.

Some code already was doing that (for example, pcap-bpf.c if fetching
the DLT list with an ioctl), and, if you can't allocate a DLT_ list,
which is usually pretty small, you may have other memory allocation
problems later, so letting the program open an interface (and not get a
correct list of all link-layer types supported) may not be worth it.

1 files changed, 8 insertions, 7 deletions

diff --git a/pcap-pf.c b/pcap-pf.c
index da08510d..2e231bec 100644
--- a/pcap-pf.c
+++ b/pcap-pf.c
@@ -404,14 +404,15 @@ pcap_activate_pf(pcap_t *p)
 		 * Ethernet framing).
 		 */
 		p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
-		/*
-		 * If that fails, just leave the list empty.
-		 */
-		if (p->dlt_list != NULL) {
-			p->dlt_list[0] = DLT_EN10MB;
-			p->dlt_list[1] = DLT_DOCSIS;
-			p->dlt_count = 2;
+		if (p->dlt_list == NULL) {
+			pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+			    errno, "malloc");
+			err = PCAP_ERROR;
+			goto bad;
 		}
+		p->dlt_list[0] = DLT_EN10MB;
+		p->dlt_list[1] = DLT_DOCSIS;
+		p->dlt_count = 2;
 		break;
 
 	case ENDT_FDDI: