Commit 672ca65d authored Aug 10, 2016 by Parthasarathy Bhuvaragan Committed by David S. Miller Aug 10, 2016

tipc: fix variable dereference before NULL check



In commit cf6f7e1d ("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: cf6f7e1d ("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>

parent 293fddff

net/tipc/monitor.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -728,12 +728,13 @@ int tipc_nl_add_monitor_peer(struct net net, struct tipc_nl_msg msg,
		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)