pimd: fix crash unconfiguring rp keepalive timer

pimd crashs while unconfigure of rp ka timer as we are trying to access
a yand dnode(suppress timer) which does not exist at the moment.

User just configured rp keepalive timer and not suppress timer,
the yang dnode would not be present. Instead of directly accessing
yang_dnode_get_unit16, first check the yang node exist using
the xpath.

Ticket: #3874971

Testing:

Before:
------
tor-11(config)# no ip pim rp keep-alive-timer 3000
vtysh: error reading from pimd: Success (0)Warning: closing connection to pimd because of an I/O error!

Broadcast message from root@tor-11 (somewhere) (Mon Apr 22 17:29:12 2024):

cumulus-core: Running cl-support for core files "pimd.25467.1713806952.core"

After:
-----
tor-11(config)# no ip pim rp keep-alive-timer 3000
tor-11(config)#

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

diff --git a/pimd/pim_cmd_common.c b/pimd/pim_cmd_common.c
index ee318d45e3d4dfef6a4a6b8687c67d8278863d05..5e50a09355cf0ee564ad20b45431ea8a60432e46 100644 (file)
--- a/pimd/pim_cmd_common.c
+++ b/pimd/pim_cmd_common.c
@@ -287,8 +287,15 @@ int pim_process_no_rp_kat_cmd(struct vty *vty)
                sizeof(rs_timer_xpath));
 
        /* RFC4601 */
-       v = yang_dnode_get_uint16(vty->candidate_config->dnode, "%s",
-                                 rs_timer_xpath);
+       /* Check if register suppress time is configured or assigned
+        * the default register suppress time.
+        */
+       if (yang_dnode_exists(vty->candidate_config->dnode, rs_timer_xpath))
+               v = yang_dnode_get_uint16(vty->candidate_config->dnode, "%s",
+                                         rs_timer_xpath);
+       else
+               v = PIM_REGISTER_SUPPRESSION_TIME_DEFAULT;
+
        v = 3 * v + PIM_REGISTER_PROBE_TIME_DEFAULT;
        if (v > UINT16_MAX)
                v = UINT16_MAX;