From: Davide Caratti Date: Fri, 22 Feb 2019 11:33:26 +0000 (+0100) Subject: net/sched: act_skbedit: fix refcount leak when replace fails X-Git-Tag: v4.20.15~19 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cbfd37c79e8c747446a30777f7ed52e4588dbb47;p=thirdparty%2Fkernel%2Fstable.git net/sched: act_skbedit: fix refcount leak when replace fails [ Upstream commit 6191da98062d25276a3b88fb2a94dcbcfb3ea65d ] 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c index 64dba3708fce2..cfceed28c3331 100644 --- a/net/sched/act_skbedit.c +++ b/net/sched/act_skbedit.c @@ -189,8 +189,7 @@ static int tcf_skbedit_init(struct net *net, struct nlattr *nla, params_new = kzalloc(sizeof(*params_new), GFP_KERNEL); if (unlikely(!params_new)) { - if (ret == ACT_P_CREATED) - tcf_idr_release(*a, bind); + tcf_idr_release(*a, bind); return -ENOMEM; }