pimd: Create pimreg interface when we start any interface config

When you configure interface configuration without explicitly
configuring pim on that interface, we were not creating the pimreg
interface and as such we would crash in an attempted register
since the pimreg device is non-existent.

The crash is this:
==8823== Invalid read of size 8
==8823==    at 0x468614: pim_channel_add_oif (pim_oil.c:392)
==8823==    by 0x46D0F1: pim_register_join (pim_register.c:61)
==8823==    by 0x449AB3: pim_mroute_msg_nocache (pim_mroute.c:242)
==8823==    by 0x449AB3: pim_mroute_msg (pim_mroute.c:661)
==8823==    by 0x449AB3: mroute_read (pim_mroute.c:707)
==8823==    by 0x4FC0676: thread_call (thread.c:1549)
==8823==    by 0x4EF3A2F: frr_run (libfrr.c:1064)
==8823==    by 0x40DCB5: main (pim_main.c:162)
==8823==  Address 0xc8 is not stack'd, malloc'd or (recently) free'd

pim_register_join calls pim_channel_add_oif with:

	pim_channel_add_oif(up->channel_oil, pim->regiface,
			    PIM_OIF_FLAG_PROTO_PIM);

We just need to make srue pim->regiface exists once we start configuring
pim.

Fixes: #5358
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

diff --git a/pimd/pim_cmd.c b/pimd/pim_cmd.c
index 28b4af9457f78b1b6ef3197a5b861c38990d7cb5..4b5346421537f1cf57decb45c7192225d2ba521c 100644 (file)
--- a/pimd/pim_cmd.c
+++ b/pimd/pim_cmd.c
@@ -7385,12 +7385,14 @@ static int pim_cmd_interface_add(struct interface *ifp)
        struct pim_interface *pim_ifp = ifp->info;
 
        if (!pim_ifp)
-               (void)pim_if_new(ifp, false, true, false, false);
+               pim_ifp = pim_if_new(ifp, false, true, false, false);
        else
                PIM_IF_DO_PIM(pim_ifp->options);
 
        pim_if_addr_add_all(ifp);
        pim_if_membership_refresh(ifp);
+
+       pim_if_create_pimreg(pim_ifp->pim);
        return 1;
 }