*: Fix usage of bfd_adj_event

Valgrind reports:

469901-==469901==
469901-==469901== Conditional jump or move depends on uninitialised value(s)
469901:==469901==    at 0x3A090D: bgp_bfd_dest_update (bgp_bfd.c:416)
469901-==469901==    by 0x497469E: zclient_read (zclient.c:3701)
469901-==469901==    by 0x4955AEC: thread_call (thread.c:1684)
469901-==469901==    by 0x48FF64E: frr_run (libfrr.c:1126)
469901-==469901==    by 0x213AB3: main (bgp_main.c:540)
469901-==469901==  Uninitialised value was created by a stack allocation
469901:==469901==    at 0x3A0725: bgp_bfd_dest_update (bgp_bfd.c:376)
469901-==469901==
469901-==469901== Conditional jump or move depends on uninitialised value(s)
469901:==469901==    at 0x3A093C: bgp_bfd_dest_update (bgp_bfd.c:421)
469901-==469901==    by 0x497469E: zclient_read (zclient.c:3701)
469901-==469901==    by 0x4955AEC: thread_call (thread.c:1684)
469901-==469901==    by 0x48FF64E: frr_run (libfrr.c:1126)
469901-==469901==    by 0x213AB3: main (bgp_main.c:540)
469901-==469901==  Uninitialised value was created by a stack allocation
469901:==469901==    at 0x3A0725: bgp_bfd_dest_update (bgp_bfd.c:376)

On looking at bgp_bfd_dest_update the function call into bfd_get_peer_info
when it fails to lookup the ifindex ifp pointer just returns leaving
the dest and src prefix pointers pointing to whatever was passed in.

Let's do two things:

a) The src pointer was sometimes assumed to be passed in and sometimes not.
Forget that.  Make it always be passed in
b) memset the src and dst pointers to be all zeros.  Then when we look
at either of the pointers we are not making decisions based upon random
data in the pointers.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

diff --git a/isisd/isis_bfd.c b/isisd/isis_bfd.c
index e74af4da210d52feff50e0f839ad0a9179598fdd..4fac73511b0227447558abb502fbf2bb17595113 100644 (file)
--- a/isisd/isis_bfd.c
+++ b/isisd/isis_bfd.c
@@ -146,11 +146,11 @@ static void bfd_adj_event(struct isis_adjacency *adj, struct prefix *dst,
 static int isis_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
 {
        struct interface *ifp;
-       struct prefix dst_ip;
+       struct prefix dst_ip, src_ip;
        int status;
 
-       ifp = bfd_get_peer_info(zclient->ibuf, &dst_ip, NULL, &status,
-                               NULL, vrf_id);
+       ifp = bfd_get_peer_info(zclient->ibuf, &dst_ip, &src_ip, &status, NULL,
+                               vrf_id);
        if (!ifp || (dst_ip.family != AF_INET && dst_ip.family != AF_INET6))
                return 0;
 

diff --git a/lib/bfd.c b/lib/bfd.c
index cdf700860170f29c0d009f5dc6ca2b06a507fd65..3ab0e21af5249a1805ce2553c37edf8008c8a198 100644 (file)
--- a/lib/bfd.c
+++ b/lib/bfd.c
@@ -224,6 +224,17 @@ struct interface *bfd_get_peer_info(struct stream *s, struct prefix *dp,
        int plen;
        int local_remote_cbit;
 
+       /*
+        * If the ifindex lookup fails the
+        * rest of the data in the stream is
+        * not read.  All examples of this function
+        * call immediately use the dp->family which
+        * is not good.  Ensure we are not using
+        * random data
+        */
+       memset(dp, 0, sizeof(*dp));
+       memset(sp, 0, sizeof(*sp));
+
        /* Get interface index. */
        ifindex = stream_getl(s);
 
@@ -249,13 +260,12 @@ struct interface *bfd_get_peer_info(struct stream *s, struct prefix *dp,
        /* Get BFD status. */
        *status = stream_getl(s);
 
-       if (sp) {
-               sp->family = stream_getc(s);
+       sp->family = stream_getc(s);
+
+       plen = prefix_blen(sp);
+       stream_get(&sp->u.prefix, s, plen);
+       sp->prefixlen = stream_getc(s);
 
-               plen = prefix_blen(sp);
-               stream_get(&sp->u.prefix, s, plen);
-               sp->prefixlen = stream_getc(s);
-       }
        local_remote_cbit = stream_getc(s);
        if (remote_cbit)
                *remote_cbit = local_remote_cbit;

diff --git a/ospfd/ospf_bfd.c b/ospfd/ospf_bfd.c
index 46407209529ef17343f268df13da4abe0a0697fb..a9bc9069d20f3f509281deafa3781389aef8ae39 100644 (file)
--- a/ospfd/ospf_bfd.c
+++ b/ospfd/ospf_bfd.c
@@ -205,14 +205,14 @@ static int ospf_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
        struct ospf_neighbor *nbr = NULL;
        struct route_node *node;
        struct route_node *n_node;
-       struct prefix p;
+       struct prefix p, src_p;
        int status;
        int old_status;
        struct bfd_info *bfd_info;
        struct timeval tv;
 
-       ifp = bfd_get_peer_info(zclient->ibuf, &p, NULL, &status,
-                               NULL, vrf_id);
+       ifp = bfd_get_peer_info(zclient->ibuf, &p, &src_p, &status, NULL,
+                               vrf_id);
 
        if ((ifp == NULL) || (p.family != AF_INET))
                return 0;

diff --git a/pimd/pim_bfd.c b/pimd/pim_bfd.c
index 1d653cdc3f01c5bb48731af1389cfd192654f6cd..5e1b9a69e14f337e45e1cb9b15f443b4f937eab4 100644 (file)
--- a/pimd/pim_bfd.c
+++ b/pimd/pim_bfd.c
@@ -217,7 +217,7 @@ static int pim_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
 {
        struct interface *ifp = NULL;
        struct pim_interface *pim_ifp = NULL;
-       struct prefix p;
+       struct prefix p, src_p;
        int status;
        char msg[100];
        int old_status;
@@ -227,8 +227,8 @@ static int pim_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
        struct listnode *neigh_nextnode = NULL;
        struct pim_neighbor *neigh = NULL;
 
-       ifp = bfd_get_peer_info(zclient->ibuf, &p, NULL, &status,
-                               NULL, vrf_id);
+       ifp = bfd_get_peer_info(zclient->ibuf, &p, &src_p, &status, NULL,
+                               vrf_id);
 
        if ((ifp == NULL) || (p.family != AF_INET))
                return 0;