[PATCH v3 net-next 2/2] tools: psock_tpacket: block Rx until socket filter has been added and socket has been bound to loopback.
From: Sowmini Varadhan <hidden>
Date: 2017-01-04 18:46:16
Subsystem:
kernel selftest framework, networking [general], the rest · Maintainers:
Shuah Khan, Shuah Khan, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Packets from any/all interfaces may be queued up on the PF_PACKET socket before it is bound to the loopback interface by psock_tpacket, and when these are passed up by the kernel, they could interfere with the Rx tests. Avoid interference from spurious packet by blocking Rx until the socket filter has been set up, and the packet has been bound to the desired (lo) interface. The effective sequence is socket(PF_PACKET, SOCK_RAW, 0); set up ring Invoke SO_ATTACH_FILTER bind to sll_protocol set to ETH_P_ALL, sll_ifindex for lo After this sequence, the only packets that will be passed up are those received on loopback that pass the attached filter. Signed-off-by: Sowmini Varadhan <redacted> --- v2: patch reworked based on comments from Willem de Bruijn tools/testing/selftests/net/psock_tpacket.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/net/psock_tpacket.c b/tools/testing/selftests/net/psock_tpacket.c
index 4a1bc64..7f6cd9f 100644
--- a/tools/testing/selftests/net/psock_tpacket.c
+++ b/tools/testing/selftests/net/psock_tpacket.c@@ -110,7 +110,7 @@ struct block_desc { static int pfsocket(int ver) { - int ret, sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL)); + int ret, sock = socket(PF_PACKET, SOCK_RAW, 0); if (sock == -1) { perror("socket"); exit(1);
@@ -239,7 +239,6 @@ static void walk_v1_v2_rx(int sock, struct ring *ring) bug_on(ring->type != PACKET_RX_RING); pair_udp_open(udp_sock, PORT_BASE); - pair_udp_setfilter(sock); memset(&pfd, 0, sizeof(pfd)); pfd.fd = sock;
@@ -601,7 +600,6 @@ static void walk_v3_rx(int sock, struct ring *ring) bug_on(ring->type != PACKET_RX_RING); pair_udp_open(udp_sock, PORT_BASE); - pair_udp_setfilter(sock); memset(&pfd, 0, sizeof(pfd)); pfd.fd = sock;
@@ -741,6 +739,8 @@ static void bind_ring(int sock, struct ring *ring) { int ret; + pair_udp_setfilter(sock); + ring->ll.sll_family = PF_PACKET; ring->ll.sll_protocol = htons(ETH_P_ALL); ring->ll.sll_ifindex = if_nametoindex("lo");
--
1.7.1