bgpd: Fix crash for `show ip bgp vrf all all neighbors 192.168.0.1 ...`

When `all` is specified BGP pointer is always NULL, we need to iterate over
all instances separately.

```
Received signal 11 at 1648199394 (si_addr 0x30, PC 0x562e96597090); aborting...
 /usr/local/lib/libfrr.so.0(zlog_backtrace_sigsafe+0x5e) [0x7f378a57ff6e]
 /usr/local/lib/libfrr.so.0(zlog_signal+0xe6) [0x7f378a580146]
 /usr/local/lib/libfrr.so.0(+0xcd4c2) [0x7f378a5aa4c2]
 /lib/x86_64-linux-gnu/libpthread.so.0(+0x14140) [0x7f378a33e140]
 /usr/lib/frr/bgpd(bgp_afi_safi_peer_exists+0) [0x562e96597090]
 /usr/lib/frr/bgpd(+0x15c3b8) [0x562e9654a3b8]
```

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit 75ce3b14f3689f17621740db86f1522e1a8b4b0b)

diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index b297ca00625630337f82de9c84e925cfd00274b3..42ffa3e6e673189e4c1d329e69e27f3f20e8f654 100644 (file)
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -13965,6 +13965,8 @@ DEFPY (show_ip_bgp_instance_neighbor_advertised_route,
        int idx = 0;
        bool first = true;
        uint16_t show_flags = 0;
+       struct listnode *node;
+       struct bgp *abgp;
 
        if (uj) {
                argc--;
@@ -14016,42 +14018,52 @@ DEFPY (show_ip_bgp_instance_neighbor_advertised_route,
            || CHECK_FLAG(show_flags, BGP_SHOW_OPT_AFI_IP6)) {
                afi = CHECK_FLAG(show_flags, BGP_SHOW_OPT_AFI_IP) ? AFI_IP
                                                                  : AFI_IP6;
-               FOREACH_SAFI (safi) {
-                       if (!bgp_afi_safi_peer_exists(bgp, afi, safi))
-                               continue;
+               for (ALL_LIST_ELEMENTS_RO(bm->bgp, node, abgp)) {
+                       FOREACH_SAFI (safi) {
+                               if (!bgp_afi_safi_peer_exists(abgp, afi, safi))
+                                       continue;
 
-                       if (uj) {
-                               if (first)
-                                       first = false;
-                               else
-                                       vty_out(vty, ",\n");
-                               vty_out(vty, "\"%s\":",
-                                       get_afi_safi_str(afi, safi, true));
-                       } else
-                               vty_out(vty, "\nFor address family: %s\n",
-                                       get_afi_safi_str(afi, safi, false));
+                               if (uj) {
+                                       if (first)
+                                               first = false;
+                                       else
+                                               vty_out(vty, ",\n");
+                                       vty_out(vty, "\"%s\":",
+                                               get_afi_safi_str(afi, safi,
+                                                                true));
+                               } else
+                                       vty_out(vty,
+                                               "\nFor address family: %s\n",
+                                               get_afi_safi_str(afi, safi,
+                                                                false));
 
-                       peer_adj_routes(vty, peer, afi, safi, type, rmap_name,
-                                       show_flags);
+                               peer_adj_routes(vty, peer, afi, safi, type,
+                                               rmap_name, show_flags);
+                       }
                }
        } else {
-               FOREACH_AFI_SAFI (afi, safi) {
-                       if (!bgp_afi_safi_peer_exists(bgp, afi, safi))
-                               continue;
+               for (ALL_LIST_ELEMENTS_RO(bm->bgp, node, abgp)) {
+                       FOREACH_AFI_SAFI (afi, safi) {
+                               if (!bgp_afi_safi_peer_exists(abgp, afi, safi))
+                                       continue;
 
-                       if (uj) {
-                               if (first)
-                                       first = false;
-                               else
-                                       vty_out(vty, ",\n");
-                               vty_out(vty, "\"%s\":",
-                                       get_afi_safi_str(afi, safi, true));
-                       } else
-                               vty_out(vty, "\nFor address family: %s\n",
-                                       get_afi_safi_str(afi, safi, false));
+                               if (uj) {
+                                       if (first)
+                                               first = false;
+                                       else
+                                               vty_out(vty, ",\n");
+                                       vty_out(vty, "\"%s\":",
+                                               get_afi_safi_str(afi, safi,
+                                                                true));
+                               } else
+                                       vty_out(vty,
+                                               "\nFor address family: %s\n",
+                                               get_afi_safi_str(afi, safi,
+                                                                false));
 
-                       peer_adj_routes(vty, peer, afi, safi, type, rmap_name,
-                                       show_flags);
+                               peer_adj_routes(vty, peer, afi, safi, type,
+                                               rmap_name, show_flags);
+                       }
                }
        }
        if (uj)