These changes are a raw update to a vanilla kernel 4.1.10, with the

recently announced rt patch patch-4.1.10-rt10.patch. No further changes
needed.

Change-Id: I9a0cf084498133b10771e744b6da4b29dff706ba
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

7 files changed, 74 insertions, 39 deletions

diff --git a/kernel/net/sched/act_api.c b/kernel/net/sched/act_api.c
index 3d43e4979..f8d9c2a2c 100644
--- a/kernel/net/sched/act_api.c
+++ b/kernel/net/sched/act_api.c
@@ -45,7 +45,7 @@ void tcf_hash_destroy(struct tc_action *a)
 }
 EXPORT_SYMBOL(tcf_hash_destroy);
 
-int tcf_hash_release(struct tc_action *a, int bind)
+int __tcf_hash_release(struct tc_action *a, bool bind, bool strict)
 {
 	struct tcf_common *p = a->priv;
 	int ret = 0;
@@ -53,7 +53,7 @@ int tcf_hash_release(struct tc_action *a, int bind)
 	if (p) {
 		if (bind)
 			p->tcfc_bindcnt--;
-		else if (p->tcfc_bindcnt > 0)
+		else if (strict && p->tcfc_bindcnt > 0)
 			return -EPERM;
 
 		p->tcfc_refcnt--;
@@ -64,9 +64,10 @@ int tcf_hash_release(struct tc_action *a, int bind)
 			ret = 1;
 		}
 	}
+
 	return ret;
 }
-EXPORT_SYMBOL(tcf_hash_release);
+EXPORT_SYMBOL(__tcf_hash_release);
 
 static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
 			   struct tc_action *a)
@@ -136,7 +137,7 @@ static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a)
 		head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
 		hlist_for_each_entry_safe(p, n, head, tcfc_head) {
 			a->priv = p;
-			ret = tcf_hash_release(a, 0);
+			ret = __tcf_hash_release(a, false, true);
 			if (ret == ACT_P_DELETED) {
 				module_put(a->ops->owner);
 				n_i++;
@@ -413,7 +414,7 @@ int tcf_action_destroy(struct list_head *actions, int bind)
 	int ret = 0;
 
 	list_for_each_entry_safe(a, tmp, actions, list) {
-		ret = tcf_hash_release(a, bind);
+		ret = __tcf_hash_release(a, bind, true);
 		if (ret == ACT_P_DELETED)
 			module_put(a->ops->owner);
 		else if (ret < 0)
diff --git a/kernel/net/sched/act_bpf.c b/kernel/net/sched/act_bpf.c
index dc6a2d324..521ffca91 100644
--- a/kernel/net/sched/act_bpf.c
+++ b/kernel/net/sched/act_bpf.c
@@ -27,9 +27,10 @@
 struct tcf_bpf_cfg {
 	struct bpf_prog *filter;
 	struct sock_filter *bpf_ops;
-	char *bpf_name;
+	const char *bpf_name;
 	u32 bpf_fd;
 	u16 bpf_num_ops;
+	bool is_ebpf;
 };
 
 static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act,
@@ -200,6 +201,7 @@ static int tcf_bpf_init_from_ops(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 	cfg->bpf_ops = bpf_ops;
 	cfg->bpf_num_ops = bpf_num_ops;
 	cfg->filter = fp;
+	cfg->is_ebpf = false;
 
 	return 0;
 }
@@ -234,18 +236,40 @@ static int tcf_bpf_init_from_efd(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 	cfg->bpf_fd = bpf_fd;
 	cfg->bpf_name = name;
 	cfg->filter = fp;
+	cfg->is_ebpf = true;
 
 	return 0;
 }
 
+static void tcf_bpf_cfg_cleanup(const struct tcf_bpf_cfg *cfg)
+{
+	if (cfg->is_ebpf)
+		bpf_prog_put(cfg->filter);
+	else
+		bpf_prog_destroy(cfg->filter);
+
+	kfree(cfg->bpf_ops);
+	kfree(cfg->bpf_name);
+}
+
+static void tcf_bpf_prog_fill_cfg(const struct tcf_bpf *prog,
+				  struct tcf_bpf_cfg *cfg)
+{
+	cfg->is_ebpf = tcf_bpf_is_ebpf(prog);
+	cfg->filter = prog->filter;
+
+	cfg->bpf_ops = prog->bpf_ops;
+	cfg->bpf_name = prog->bpf_name;
+}
+
 static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action *act,
 			int replace, int bind)
 {
 	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
+	struct tcf_bpf_cfg cfg, old;
 	struct tc_act_bpf *parm;
 	struct tcf_bpf *prog;
-	struct tcf_bpf_cfg cfg;
 	bool is_bpf, is_ebpf;
 	int ret;
 
@@ -294,6 +318,9 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 	prog = to_bpf(act);
 	spin_lock_bh(&prog->tcf_lock);
 
+	if (ret != ACT_P_CREATED)
+		tcf_bpf_prog_fill_cfg(prog, &old);
+
 	prog->bpf_ops = cfg.bpf_ops;
 	prog->bpf_name = cfg.bpf_name;
 
@@ -309,29 +336,22 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 
 	if (ret == ACT_P_CREATED)
 		tcf_hash_insert(act);
+	else
+		tcf_bpf_cfg_cleanup(&old);
 
 	return ret;
 
 destroy_fp:
-	if (is_ebpf)
-		bpf_prog_put(cfg.filter);
-	else
-		bpf_prog_destroy(cfg.filter);
-
-	kfree(cfg.bpf_ops);
-	kfree(cfg.bpf_name);
-
+	tcf_bpf_cfg_cleanup(&cfg);
 	return ret;
 }
 
 static void tcf_bpf_cleanup(struct tc_action *act, int bind)
 {
-	const struct tcf_bpf *prog = act->priv;
+	struct tcf_bpf_cfg tmp;
 
-	if (tcf_bpf_is_ebpf(prog))
-		bpf_prog_put(prog->filter);
-	else
-		bpf_prog_destroy(prog->filter);
+	tcf_bpf_prog_fill_cfg(act->priv, &tmp);
+	tcf_bpf_cfg_cleanup(&tmp);
 }
 
 static struct tc_action_ops act_bpf_ops __read_mostly = {
diff --git a/kernel/net/sched/cls_bpf.c b/kernel/net/sched/cls_bpf.c
index 91bd9c194..c0b86f2bf 100644
--- a/kernel/net/sched/cls_bpf.c
+++ b/kernel/net/sched/cls_bpf.c
@@ -364,7 +364,7 @@ static int cls_bpf_change(struct net *net, struct sk_buff *in_skb,
 		goto errout;
 
 	if (oldprog) {
-		list_replace_rcu(&prog->link, &oldprog->link);
+		list_replace_rcu(&oldprog->link, &prog->link);
 		tcf_unbind_filter(tp, &oldprog->res);
 		call_rcu(&oldprog->rcu, __cls_bpf_delete_prog);
 	} else {
diff --git a/kernel/net/sched/cls_flow.c b/kernel/net/sched/cls_flow.c
index a620c4e28..75df923f5 100644
--- a/kernel/net/sched/cls_flow.c
+++ b/kernel/net/sched/cls_flow.c
@@ -419,6 +419,8 @@ static int flow_change(struct net *net, struct sk_buff *in_skb,
 	if (!fnew)
 		goto err2;
 
+	tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE);
+
 	fold = (struct flow_filter *)*arg;
 	if (fold) {
 		err = -EINVAL;
@@ -480,7 +482,6 @@ static int flow_change(struct net *net, struct sk_buff *in_skb,
 		fnew->mask  = ~0U;
 		fnew->tp = tp;
 		get_random_bytes(&fnew->hashrnd, 4);
-		tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE);
 	}
 
 	fnew->perturb_timer.function = flow_perturbation;
@@ -520,7 +521,7 @@ static int flow_change(struct net *net, struct sk_buff *in_skb,
 	if (*arg == 0)
 		list_add_tail_rcu(&fnew->list, &head->filters);
 	else
-		list_replace_rcu(&fnew->list, &fold->list);
+		list_replace_rcu(&fold->list, &fnew->list);
 
 	*arg = (unsigned long)fnew;
 
diff --git a/kernel/net/sched/cls_fw.c b/kernel/net/sched/cls_fw.c
index 715e01e59..f23a3b68b 100644
--- a/kernel/net/sched/cls_fw.c
+++ b/kernel/net/sched/cls_fw.c
@@ -33,7 +33,6 @@
 
 struct fw_head {
 	u32			mask;
-	bool			mask_set;
 	struct fw_filter __rcu	*ht[HTSIZE];
 	struct rcu_head		rcu;
 };
@@ -84,7 +83,7 @@ static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 			}
 		}
 	} else {
-		/* old method */
+		/* Old method: classify the packet using its skb mark. */
 		if (id && (TC_H_MAJ(id) == 0 ||
 			   !(TC_H_MAJ(id ^ tp->q->handle)))) {
 			res->classid = id;
@@ -114,14 +113,9 @@ static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 
 static int fw_init(struct tcf_proto *tp)
 {
-	struct fw_head *head;
-
-	head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
-	if (head == NULL)
-		return -ENOBUFS;
-
-	head->mask_set = false;
-	rcu_assign_pointer(tp->root, head);
+	/* We don't allocate fw_head here, because in the old method
+	 * we don't need it at all.
+	 */
 	return 0;
 }
 
@@ -252,7 +246,7 @@ static int fw_change(struct net *net, struct sk_buff *in_skb,
 	int err;
 
 	if (!opt)
-		return handle ? -EINVAL : 0;
+		return handle ? -EINVAL : 0; /* Succeed if it is old method. */
 
 	err = nla_parse_nested(tb, TCA_FW_MAX, opt, fw_policy);
 	if (err < 0)
@@ -302,11 +296,17 @@ static int fw_change(struct net *net, struct sk_buff *in_skb,
 	if (!handle)
 		return -EINVAL;
 
-	if (!head->mask_set) {
-		head->mask = 0xFFFFFFFF;
+	if (!head) {
+		u32 mask = 0xFFFFFFFF;
 		if (tb[TCA_FW_MASK])
-			head->mask = nla_get_u32(tb[TCA_FW_MASK]);
-		head->mask_set = true;
+			mask = nla_get_u32(tb[TCA_FW_MASK]);
+
+		head = kzalloc(sizeof(*head), GFP_KERNEL);
+		if (!head)
+			return -ENOBUFS;
+		head->mask = mask;
+
+		rcu_assign_pointer(tp->root, head);
 	}
 
 	f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
diff --git a/kernel/net/sched/cls_u32.c b/kernel/net/sched/cls_u32.c
index cab9e9b43..4fbb67430 100644
--- a/kernel/net/sched/cls_u32.c
+++ b/kernel/net/sched/cls_u32.c
@@ -490,6 +490,19 @@ static bool u32_destroy(struct tcf_proto *tp, bool force)
 					return false;
 			}
 		}
+
+		if (tp_c->refcnt > 1)
+			return false;
+
+		if (tp_c->refcnt == 1) {
+			struct tc_u_hnode *ht;
+
+			for (ht = rtnl_dereference(tp_c->hlist);
+			     ht;
+			     ht = rtnl_dereference(ht->next))
+				if (!ht_empty(ht))
+					return false;
+		}
 	}
 
 	if (root_ht && --root_ht->refcnt == 0)
diff --git a/kernel/net/sched/sch_fq_codel.c b/kernel/net/sched/sch_fq_codel.c
index c244c45b7..9291598b5 100644
--- a/kernel/net/sched/sch_fq_codel.c
+++ b/kernel/net/sched/sch_fq_codel.c
@@ -162,10 +162,10 @@ static unsigned int fq_codel_drop(struct Qdisc *sch)
 	skb = dequeue_head(flow);
 	len = qdisc_pkt_len(skb);
 	q->backlogs[idx] -= len;
-	kfree_skb(skb);
 	sch->q.qlen--;
 	qdisc_qstats_drop(sch);
 	qdisc_qstats_backlog_dec(sch, skb);
+	kfree_skb(skb);
 	flow->dropped++;
 	return idx;
 }