[PATCH net] net_sched: act: Delete estimator in error path.

[PATCH net] net_sched: act: Delete estimator in error path.

[Hiroaki SHIMODA]

Some action modules free struct tcf_common in their error path
while estimator is still active. This results in est_timer()
dereference freed memory.
Add gen_kill_estimator() in ipt, pedit and simple action.

Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
---
 net/sched/act_ipt.c    |    7 ++++++-
 net/sched/act_pedit.c  |    5 ++++-
 net/sched/act_simple.c |    5 ++++-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 60e281a..58fb3c7 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -185,7 +185,12 @@ err3:
 err2:
 	kfree(tname);
 err1:
-	kfree(pc);
+	if (ret == ACT_P_CREATED) {
+		if (est)
+			gen_kill_estimator(&pc->tcfc_bstats,
+					   &pc->tcfc_rate_est);
+		kfree_rcu(pc, tcfc_rcu);
+	}
 	return err;
 }
 
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 26aa2f6..45c53ab 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -74,7 +74,10 @@ static int tcf_pedit_init(struct nlattr *nla, struct nlattr *est,
 		p = to_pedit(pc);
 		keys = kmalloc(ksize, GFP_KERNEL);
 		if (keys == NULL) {
-			kfree(pc);
+			if (est)
+				gen_kill_estimator(&pc->tcfc_bstats,
+						   &pc->tcfc_rate_est);
+			kfree_rcu(pc, tcfc_rcu);
 			return -ENOMEM;
 		}
 		ret = ACT_P_CREATED;
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index 3922f2a..3714f60 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -131,7 +131,10 @@ static int tcf_simp_init(struct nlattr *nla, struct nlattr *est,
 		d = to_defact(pc);
 		ret = alloc_defdata(d, defdata);
 		if (ret < 0) {
-			kfree(pc);
+			if (est)
+				gen_kill_estimator(&pc->tcfc_bstats,
+						   &pc->tcfc_rate_est);
+			kfree_rcu(pc, tcfc_rcu);
 			return ret;
 		}
 		d->tcf_action = parm->action;
-- 
1.7.8.6

Re: [PATCH net] net_sched: act: Delete estimator in error path.

[David Miller]

From: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Date: Tue, 7 Aug 2012 00:45:48 +0900

> Some action modules free struct tcf_common in their error path
> while estimator is still active. This results in est_timer()
> dereference freed memory.
> Add gen_kill_estimator() in ipt, pedit and simple action.
> 
> Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>

Applied.