From 46caeeca78a663cfa5c3467a03962ee81dc2358e Mon Sep 17 00:00:00 2001
From: Hans Petter Selasky <hselasky@FreeBSD.org>
Date: Wed, 12 Dec 2018 09:51:10 +0000
Subject: [PATCH] Don't register IOCTLs with capsicum when there is no valid
 file descriptor. This fixes tcpdump when using mlx5_X devices.

Differential Revision:	https://reviews.freebsd.org/D18499
Reviewed by:		kib@, slavash@, oshogbo@
MFC after:		1 week
Sponsored by:		Mellanox Technologies
---
 contrib/tcpdump/tcpdump.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/tcpdump/tcpdump.c b/contrib/tcpdump/tcpdump.c
index 7d59e8952406..647a3d1aff37 100644
--- a/contrib/tcpdump/tcpdump.c
+++ b/contrib/tcpdump/tcpdump.c
@@ -1915,7 +1915,7 @@ main(int argc, char **argv)
 	if (pcap_setfilter(pd, &fcode) < 0)
 		error("%s", pcap_geterr(pd));
 #ifdef HAVE_CAPSICUM
-	if (RFileName == NULL && VFileName == NULL) {
+	if (RFileName == NULL && VFileName == NULL && pcap_fileno(pd) != -1) {
 		static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
 
 		/*