net/sched: fix idr leak in the error path of tcp_pedit_init()

tcf_pedit_init() can fail to allocate 'keys' after the idr has been
successfully reserved. When this happens, subsequent attempts to configure
a pedit rule using the same idr value systematically fail with -ENOSPC:

 # tc action add action pedit munge ip ttl set 63 index 100
 RTNETLINK answers: Cannot allocate memory
 We have an error talking to the kernel
 # tc action add action pedit munge ip ttl set 63 index 100
 RTNETLINK answers: No space left on device
 We have an error talking to the kernel
 # tc action add action pedit munge ip ttl set 63 index 100
 RTNETLINK answers: No space left on device
 We have an error talking to the kernel
 ...

Fix this in the error path of tcf_act_pedit_init(), calling
tcf_idr_release() in place of tcf_idr_cleanup().

Fixes: 65a206c01e8e ("net/sched: Change act_api and act_xxx modules to use IDR")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/act_pedit.c

@@ -176,7 +176,7 @@ static int tcf_pedit_init(struct net *net, struct nlattr *nla,
 		p = to_pedit(*a);
 		keys = kmalloc(ksize, GFP_KERNEL);
 		if (keys == NULL) {
-			tcf_idr_cleanup(*a, est);
+			tcf_idr_release(*a, bind);
 			kfree(keys_ex);
 			return -ENOMEM;
 		}