net/sched: act_skbedit: fix refcount leak when replace fails
authorDavide Caratti <dcaratti@redhat.com>
Fri, 22 Feb 2019 11:33:26 +0000 (12:33 +0100)
committerDavid S. Miller <davem@davemloft.net>
Mon, 25 Feb 2019 01:31:43 +0000 (17:31 -0800)
commit6191da98062d25276a3b88fb2a94dcbcfb3ea65d
treeaf18b890509ab7f2d3fc3a9ab75947f51ca409f6
parent8f67c90ee9148eab3d2b4393c3cf76489b27f87c
net/sched: act_skbedit: fix refcount leak when replace fails

when act_skbedit was converted to use RCU in the data plane, we added an
error path, but we forgot to drop the action refcount in case of failure
during a 'replace' operation:

 # tc actions add action skbedit ptype otherhost pass index 100
 # tc action show action skbedit
 total acts 1

         action order 0: skbedit  ptype otherhost pass
          index 100 ref 1 bind 0
 # tc actions replace action skbedit ptype otherhost drop index 100
 RTNETLINK answers: Cannot allocate memory
 We have an error talking to the kernel
 # tc action show action skbedit
 total acts 1

         action order 0: skbedit  ptype otherhost pass
          index 100 ref 2 bind 0

Ensure we call tcf_idr_release(), in case 'params_new' allocation failed,
also when the action is being replaced.

Fixes: c749cdda9089 ("net/sched: act_skbedit: don't use spinlock in the data path")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sched/act_skbedit.c