When binding to AF_PACKET linux kernel sockets, the interface name is not passed in when given -- it is always "".  This causes problems, for example, receiving packets to a "monitor0" interface doesn't work.

diff -r a6548e230ed6 Modules/socketmodule.c
--- a/Modules/socketmodule.c    Thu Oct 27 19:33:22 2016 +0300
+++ b/Modules/socketmodule.c    Thu Oct 27 11:13:12 2016 -0700
@@ -1344,6 +1344,7 @@
     {
         struct sockaddr_ll *a = (struct sockaddr_ll *)addr;
         char *ifname = "";
+        // ^^ ifname should be set to interface name passed in via sockaddr.
         struct ifreq ifr;
         /* need to look up interface name give index */
         if (a->sll_ifindex) {

Just for clarity, the high level bug is that when binding to an interface using AF_PACKET, transmissions work, but receive does not:

    sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, ETH_P_IEEE802154)
    sock.bind(("monitor0", ETH_P_IEEE802154))

    sock.send(test_frame)   # transmission works fine
    pkt = sock.recv(127)    # never receives, though C test works fine

The same test written in C that calls ioctl(sockfd, SIOCGIFNAME, &ifr) to lookup ifindex for bind from ifname="monitor0" works fine.

If I bind to port 0, it works for both tx and rx.  Sorry for the false alarm!

sock.bind(("monitor0", 0))