3 files changed, 158 insertions, 0 deletions
diff --git a/tests/sys/net/bpf/Makefile b/tests/sys/net/bpf/Makefile
new file mode 100644
index 000000000000..9c8a25b15d16
--- /dev/null
+++ b/tests/sys/net/bpf/Makefile
@@ -0,0 +1,15 @@
+.include <src.opts.mk>
+
+PACKAGE=	tests
+
+TESTSDIR=	${TESTSBASE}/sys/net/bpf
+BINDIR=		${TESTSDIR}
+
+LIBADD+=	nv
+
+PROGS=	bpf_multi_read
+LIBADD.bpf_multi_read+=	pcap
+
+ATF_TESTS_SH=	bpf
+
+.include <bsd.test.mk>
diff --git a/tests/sys/net/bpf/bpf.sh b/tests/sys/net/bpf/bpf.sh
new file mode 100644
index 000000000000..2830c4862de9
--- /dev/null
+++ b/tests/sys/net/bpf/bpf.sh
@@ -0,0 +1,67 @@
+##
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2025 Rubicon Communications, LLC ("Netgate")
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+. $(atf_get_srcdir)/../../common/vnet.subr
+
+atf_test_case "multi_read" "cleanup"
+multi_read_head()
+{
+	atf_set descr 'Test multiple readers on /dev/bpf'
+	atf_set require.user root
+}
+
+multi_read_body()
+{
+	vnet_init
+
+	epair=$(vnet_mkepair)
+	ifconfig ${epair}a inet 192.0.2.1/24 up
+
+	vnet_mkjail alcatraz ${epair}b
+	jexec alcatraz ifconfig ${epair}b inet 192.0.2.2/24 up
+
+	atf_check -s exit:0 -o ignore \
+	    ping -c 1 192.0.2.2
+
+	# Start a multi-thread (or multi-process) read on bpf
+	$(atf_get_srcdir)/bpf_multi_read ${epair}a &
+
+	# Generate traffic
+	ping -f 192.0.2.2 >/dev/null 2>&1 &
+
+	# Now let this run for 10 seconds
+	sleep 10
+}
+
+multi_read_cleanup()
+{
+	vnet_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "multi_read"
+}
diff --git a/tests/sys/net/bpf/bpf_multi_read.c b/tests/sys/net/bpf/bpf_multi_read.c
new file mode 100644
index 000000000000..3a8edd76d623
--- /dev/null
+++ b/tests/sys/net/bpf/bpf_multi_read.c
@@ -0,0 +1,76 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 Rubicon Communications, LLC (Netgate)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include <err.h>
+#include <stdio.h>
+#include <pcap.h>
+#include <unistd.h>
+
+static void
+callback(u_char *arg __unused, const struct pcap_pkthdr *hdr __unused,
+    const unsigned char *bytes __unused)
+{
+}
+
+int
+main(int argc, const char **argv)
+{
+	pcap_t *pcap;
+	const char *interface;
+	char errbuf[PCAP_ERRBUF_SIZE] = { 0 };
+	int ret;
+
+	if (argc != 2)
+		err(1, "Usage: %s <interface>\n", argv[0]);
+
+	interface = argv[1];
+
+	pcap = pcap_create(interface, errbuf);
+	if (! pcap)
+		perror("Failed to pcap interface");
+
+	ret = pcap_set_snaplen(pcap, 86);
+	if (ret != 0)
+		perror("Failed to set snaplen");
+
+	ret = pcap_set_timeout(pcap, 100);
+	if (ret != 0)
+		perror("Failed to set timeout");
+
+	ret = pcap_activate(pcap);
+	if (ret != 0)
+		perror("Failed to activate");
+
+	/* So we have two readers on one /dev/bpf fd */
+	fork();
+
+	printf("Interface open\n");
+	pcap_loop(pcap, 0, callback, NULL);
+
+	return (0);
+}