tipc: fix variable dereference before NULL check
In commit cf6f7e1d5109 ("tipc: dump monitor attributes"),
I dereferenced a pointer before checking if its valid.
This is reported by static check Smatch as:
net/tipc/monitor.c:733 tipc_nl_add_monitor_peer()
warn: variable dereferenced before check 'mon' (see line 731)
In this commit, we check for a valid monitor before proceeding
with any other operation.
Fixes: cf6f7e1d5109 ("tipc: dump monitor attributes")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/monitor.c b/net/tipc/monitor.c
index b62caa1..ed97a58 100644
--- a/net/tipc/monitor.c
+++ b/net/tipc/monitor.c
@@ -728,12 +728,13 @@
u32 bearer_id, u32 *prev_node)
{
struct tipc_monitor *mon = tipc_monitor(net, bearer_id);
- struct tipc_peer *peer = mon->self;
+ struct tipc_peer *peer;
if (!mon)
return -EINVAL;
read_lock_bh(&mon->lock);
+ peer = mon->self;
do {
if (*prev_node) {
if (peer->addr == *prev_node)