1 files changed, 32 insertions, 14 deletions

diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index eb0e9458e722..6640e75eaa02 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -12,6 +12,7 @@
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/refcount.h>
+#include <linux/rcupdate.h>
 #include <net/act_api.h>
 #include <net/netlink.h>
 #include <net/pkt_cls.h>
@@ -333,12 +334,13 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		  struct tcindex_filter_result *r, struct nlattr **tb,
 		  struct nlattr *est, u32 flags, struct netlink_ext_ack *extack)
 {
-	struct tcindex_filter_result new_filter_result, *old_r = r;
+	struct tcindex_filter_result new_filter_result;
 	struct tcindex_data *cp = NULL, *oldp;
 	struct tcindex_filter *f = NULL; /* make gcc behave */
 	struct tcf_result cr = {};
 	int err, balloc = 0;
 	struct tcf_exts e;
+	bool update_h = false;
 
 	err = tcf_exts_init(&e, net, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 	if (err < 0)
@@ -402,7 +404,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	err = tcindex_filter_result_init(&new_filter_result, cp, net);
 	if (err < 0)
 		goto errout_alloc;
-	if (old_r)
+	if (r)
 		cr = r->res;
 
 	err = -EBUSY;
@@ -456,10 +458,13 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		}
 	}
 
-	if (cp->perfect)
+	if (cp->perfect) {
 		r = cp->perfect + handle;
-	else
-		r = tcindex_lookup(cp, handle) ? : &new_filter_result;
+	} else {
+		/* imperfect area is updated in-place using rcu */
+		update_h = !!tcindex_lookup(cp, handle);
+		r = &new_filter_result;
+	}
 
 	if (r == &new_filter_result) {
 		f = kzalloc(sizeof(*f), GFP_KERNEL);
@@ -479,21 +484,34 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		tcf_bind_filter(tp, &cr, base);
 	}
 
-	if (old_r && old_r != r) {
-		err = tcindex_filter_result_init(old_r, cp, net);
-		if (err < 0) {
-			kfree(f);
-			goto errout_alloc;
-		}
-	}
-
 	oldp = p;
 	r->res = cr;
 	tcf_exts_change(&r->exts, &e);
 
 	rcu_assign_pointer(tp->root, cp);
 
-	if (r == &new_filter_result) {
+	if (update_h) {
+		struct tcindex_filter __rcu **fp;
+		struct tcindex_filter *cf;
+
+		f->result.res = r->res;
+		tcf_exts_change(&f->result.exts, &r->exts);
+
+		/* imperfect area bucket */
+		fp = cp->h + (handle % cp->hash);
+
+		/* lookup the filter, guaranteed to exist */
+		for (cf = rcu_dereference_bh_rtnl(*fp); cf;
+		     fp = &cf->next, cf = rcu_dereference_bh_rtnl(*fp))
+			if (cf->key == (u16)handle)
+				break;
+
+		f->next = cf->next;
+
+		cf = rcu_replace_pointer(*fp, f, 1);
+		tcf_exts_get_net(&cf->result.exts);
+		tcf_queue_work(&cf->rwork, tcindex_destroy_fexts_work);
+	} else if (r == &new_filter_result) {
 		struct tcindex_filter *nfp;
 		struct tcindex_filter __rcu **fp;