mctp: fix use after free

Clang static analysis reports this problem
route.c:425:4: warning: Use of memory after it is freed
  trace_mctp_key_acquire(key);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
When mctp_key_add() fails, key is freed but then is later
used in trace_mctp_key_acquire().  Add an else statement
to use the key only when mctp_key_add() is successful.

Fixes: 4f9e1ba6de ("mctp: Add tracepoints for tag/key handling")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Rix 2022-02-14 18:05:41 -08:00 committed by David S. Miller
parent ef57640575
commit 7e5b6a5c8c

View File

@ -412,13 +412,14 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
* this function.
*/
rc = mctp_key_add(key, msk);
if (rc)
if (rc) {
kfree(key);
} else {
trace_mctp_key_acquire(key);
trace_mctp_key_acquire(key);
/* we don't need to release key->lock on exit */
mctp_key_unref(key);
/* we don't need to release key->lock on exit */
mctp_key_unref(key);
}
key = NULL;
} else {