net/sched: Retire tcindex classifier

The tcindex classifier has served us well for about a quarter of a century
but has not been getting much TLC due to lack of known users. Most recently
it has become easy prey to syzkaller. For this reason, we are retiring it.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

include/net/tc_wrapper.h

@@ -154,7 +154,6 @@ TC_INDIRECT_FILTER_DECLARE(mall_classify);
 TC_INDIRECT_FILTER_DECLARE(route4_classify);
 TC_INDIRECT_FILTER_DECLARE(rsvp_classify);
 TC_INDIRECT_FILTER_DECLARE(rsvp6_classify);
-TC_INDIRECT_FILTER_DECLARE(tcindex_classify);
 TC_INDIRECT_FILTER_DECLARE(u32_classify);
 
 static inline int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
@@ -207,10 +206,6 @@ static inline int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 	if (tp->classify == rsvp6_classify)
 		return rsvp6_classify(skb, tp, res);
 #endif
-#if IS_BUILTIN(CONFIG_NET_CLS_TCINDEX)
-	if (tp->classify == tcindex_classify)
-		return tcindex_classify(skb, tp, res);
-#endif
 
 skip:
 	return tp->classify(skb, tp, res);

net/sched/Kconfig

@@ -468,17 +468,6 @@ config NET_CLS_BASIC
 	  To compile this code as a module, choose M here: the
 	  module will be called cls_basic.
 
-config NET_CLS_TCINDEX
-	tristate "Traffic-Control Index (TCINDEX)"
-	select NET_CLS
-	help
-	  Say Y here if you want to be able to classify packets based on
-	  traffic control indices. You will want this feature if you want
-	  to implement Differentiated Services together with DSMARK.
-
-	  To compile this code as a module, choose M here: the
-	  module will be called cls_tcindex.
-
 config NET_CLS_ROUTE4
 	tristate "Routing decision (ROUTE)"
 	depends on INET

net/sched/Makefile

@@ -68,7 +68,6 @@ obj-$(CONFIG_NET_CLS_U32)	+= cls_u32.o
 obj-$(CONFIG_NET_CLS_ROUTE4)	+= cls_route.o
 obj-$(CONFIG_NET_CLS_FW)	+= cls_fw.o
 obj-$(CONFIG_NET_CLS_RSVP)	+= cls_rsvp.o
-obj-$(CONFIG_NET_CLS_TCINDEX)	+= cls_tcindex.o
 obj-$(CONFIG_NET_CLS_RSVP6)	+= cls_rsvp6.o
 obj-$(CONFIG_NET_CLS_BASIC)	+= cls_basic.o
 obj-$(CONFIG_NET_CLS_FLOW)	+= cls_flow.o

net/sched/cls_tcindex.c

-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * net/sched/cls_tcindex.c	Packet classifier for skb->tc_index
- *
- * Written 1998,1999 by Werner Almesberger, EPFL ICA
- */
-
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/skbuff.h>
-#include <linux/errno.h>
-#include <linux/slab.h>
-#include <linux/refcount.h>
-#include <net/act_api.h>
-#include <net/netlink.h>
-#include <net/pkt_cls.h>
-#include <net/sch_generic.h>
-#include <net/tc_wrapper.h>
-
-/*
- * Passing parameters to the root seems to be done more awkwardly than really
- * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
- * verified. FIXME.
- */
-
-#define PERFECT_HASH_THRESHOLD	64	/* use perfect hash if not bigger */
-#define DEFAULT_HASH_SIZE	64	/* optimized for diffserv */
-
-
-struct tcindex_data;
-
-struct tcindex_filter_result {
-	struct tcf_exts		exts;
-	struct tcf_result	res;
-	struct tcindex_data	*p;
-	struct rcu_work		rwork;
-};
-
-struct tcindex_filter {
-	u16 key;
-	struct tcindex_filter_result result;
-	struct tcindex_filter __rcu *next;
-	struct rcu_work rwork;
-};
-
-
-struct tcindex_data {
-	struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
-	struct tcindex_filter __rcu **h; /* imperfect hash; */
-	struct tcf_proto *tp;
-	u16 mask;		/* AND key with mask */
-	u32 shift;		/* shift ANDed key to the right */
-	u32 hash;		/* hash table size; 0 if undefined */
-	u32 alloc_hash;		/* allocated size */
-	u32 fall_through;	/* 0: only classify if explicit match */
-	refcount_t refcnt;	/* a temporary refcnt for perfect hash */
-	struct rcu_work rwork;
-};
-
-static inline int tcindex_filter_is_set(struct tcindex_filter_result *r)
-{
-	return tcf_exts_has_actions(&r->exts) || r->res.classid;
-}
-
-static void tcindex_data_get(struct tcindex_data *p)
-{
-	refcount_inc(&p->refcnt);
-}
-
-static void tcindex_data_put(struct tcindex_data *p)
-{
-	if (refcount_dec_and_test(&p->refcnt)) {
-		kfree(p->perfect);
-		kfree(p->h);
-		kfree(p);
-	}
-}
-
-static struct tcindex_filter_result *tcindex_lookup(struct tcindex_data *p,
-						    u16 key)
-{
-	if (p->perfect) {
-		struct tcindex_filter_result *f = p->perfect + key;
-
-		return tcindex_filter_is_set(f) ? f : NULL;
-	} else if (p->h) {
-		struct tcindex_filter __rcu **fp;
-		struct tcindex_filter *f;
-
-		fp = &p->h[key % p->hash];
-		for (f = rcu_dereference_bh_rtnl(*fp);
-		     f;
-		     fp = &f->next, f = rcu_dereference_bh_rtnl(*fp))
-			if (f->key == key)
-				return &f->result;
-	}
-
-	return NULL;
-}
-
-TC_INDIRECT_SCOPE int tcindex_classify(struct sk_buff *skb,
-				       const struct tcf_proto *tp,
-				       struct tcf_result *res)
-{
-	struct tcindex_data *p = rcu_dereference_bh(tp->root);
-	struct tcindex_filter_result *f;
-	int key = (skb->tc_index & p->mask) >> p->shift;
-
-	pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
-		 skb, tp, res, p);
-
-	f = tcindex_lookup(p, key);
-	if (!f) {
-		struct Qdisc *q = tcf_block_q(tp->chain->block);
-
-		if (!p->fall_through)
-			return -1;
-		res->classid = TC_H_MAKE(TC_H_MAJ(q->handle), key);
-		res->class = 0;
-		pr_debug("alg 0x%x\n", res->classid);
-		return 0;
-	}
-	*res = f->res;
-	pr_debug("map 0x%x\n", res->classid);
-
-	return tcf_exts_exec(skb, &f->exts, res);
-}
-
-
-static void *tcindex_get(struct tcf_proto *tp, u32 handle)
-{
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	struct tcindex_filter_result *r;
-
-	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
-	if (p->perfect && handle >= p->alloc_hash)
-		return NULL;
-	r = tcindex_lookup(p, handle);
-	return r && tcindex_filter_is_set(r) ? r : NULL;
-}
-
-static int tcindex_init(struct tcf_proto *tp)
-{
-	struct tcindex_data *p;
-
-	pr_debug("tcindex_init(tp %p)\n", tp);
-	p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
-	if (!p)
-		return -ENOMEM;
-
-	p->mask = 0xffff;
-	p->hash = DEFAULT_HASH_SIZE;
-	p->fall_through = 1;
-	refcount_set(&p->refcnt, 1); /* Paired with tcindex_destroy_work() */
-
-	rcu_assign_pointer(tp->root, p);
-	return 0;
-}
-
-static void __tcindex_destroy_rexts(struct tcindex_filter_result *r)
-{
-	tcf_exts_destroy(&r->exts);
-	tcf_exts_put_net(&r->exts);
-	tcindex_data_put(r->p);
-}
-
-static void tcindex_destroy_rexts_work(struct work_struct *work)
-{
-	struct tcindex_filter_result *r;
-
-	r = container_of(to_rcu_work(work),
-			 struct tcindex_filter_result,
-			 rwork);
-	rtnl_lock();
-	__tcindex_destroy_rexts(r);
-	rtnl_unlock();
-}
-
-static void __tcindex_destroy_fexts(struct tcindex_filter *f)
-{
-	tcf_exts_destroy(&f->result.exts);
-	tcf_exts_put_net(&f->result.exts);
-	kfree(f);
-}
-
-static void tcindex_destroy_fexts_work(struct work_struct *work)
-{
-	struct tcindex_filter *f = container_of(to_rcu_work(work),
-						struct tcindex_filter,
-						rwork);
-
-	rtnl_lock();
-	__tcindex_destroy_fexts(f);
-	rtnl_unlock();
-}
-
-static int tcindex_delete(struct tcf_proto *tp, void *arg, bool *last,
-			  bool rtnl_held, struct netlink_ext_ack *extack)
-{
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	struct tcindex_filter_result *r = arg;
-	struct tcindex_filter __rcu **walk;
-	struct tcindex_filter *f = NULL;
-
-	pr_debug("tcindex_delete(tp %p,arg %p),p %p\n", tp, arg, p);
-	if (p->perfect) {
-		if (!r->res.class)
-			return -ENOENT;
-	} else {
-		int i;
-
-		for (i = 0; i < p->hash; i++) {
-			walk = p->h + i;
-			for (f = rtnl_dereference(*walk); f;
-			     walk = &f->next, f = rtnl_dereference(*walk)) {
-				if (&f->result == r)
-					goto found;
-			}
-		}
-		return -ENOENT;
-
-found:
-		rcu_assign_pointer(*walk, rtnl_dereference(f->next));
-	}
-	tcf_unbind_filter(tp, &r->res);
-	/* all classifiers are required to call tcf_exts_destroy() after rcu
-	 * grace period, since converted-to-rcu actions are relying on that
-	 * in cleanup() callback
-	 */
-	if (f) {
-		if (tcf_exts_get_net(&f->result.exts))
-			tcf_queue_work(&f->rwork, tcindex_destroy_fexts_work);
-		else
-			__tcindex_destroy_fexts(f);
-	} else {
-		tcindex_data_get(p);
-
-		if (tcf_exts_get_net(&r->exts))
-			tcf_queue_work(&r->rwork, tcindex_destroy_rexts_work);
-		else
-			__tcindex_destroy_rexts(r);
-	}
-
-	*last = false;
-	return 0;
-}
-
-static void tcindex_destroy_work(struct work_struct *work)
-{
-	struct tcindex_data *p = container_of(to_rcu_work(work),
-					      struct tcindex_data,
-					      rwork);
-
-	tcindex_data_put(p);
-}
-
-static inline int
-valid_perfect_hash(struct tcindex_data *p)
-{
-	return  p->hash > (p->mask >> p->shift);
-}
-
-static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
-	[TCA_TCINDEX_HASH]		= { .type = NLA_U32 },
-	[TCA_TCINDEX_MASK]		= { .type = NLA_U16 },
-	[TCA_TCINDEX_SHIFT]		= { .type = NLA_U32 },
-	[TCA_TCINDEX_FALL_THROUGH]	= { .type = NLA_U32 },
-	[TCA_TCINDEX_CLASSID]		= { .type = NLA_U32 },
-};
-
-static int tcindex_filter_result_init(struct tcindex_filter_result *r,
-				      struct tcindex_data *p,
-				      struct net *net)
-{
-	memset(r, 0, sizeof(*r));
-	r->p = p;
-	return tcf_exts_init(&r->exts, net, TCA_TCINDEX_ACT,
-			     TCA_TCINDEX_POLICE);
-}
-
-static void tcindex_free_perfect_hash(struct tcindex_data *cp);
-
-static void tcindex_partial_destroy_work(struct work_struct *work)
-{
-	struct tcindex_data *p = container_of(to_rcu_work(work),
-					      struct tcindex_data,
-					      rwork);
-
-	rtnl_lock();
-	if (p->perfect)
-		tcindex_free_perfect_hash(p);
-	kfree(p);
-	rtnl_unlock();
-}
-
-static void tcindex_free_perfect_hash(struct tcindex_data *cp)
-{
-	int i;
-
-	for (i = 0; i < cp->hash; i++)
-		tcf_exts_destroy(&cp->perfect[i].exts);
-	kfree(cp->perfect);
-}
-
-static int tcindex_alloc_perfect_hash(struct net *net, struct tcindex_data *cp)
-{
-	int i, err = 0;
-
-	cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
-			      GFP_KERNEL | __GFP_NOWARN);
-	if (!cp->perfect)
-		return -ENOMEM;
-
-	for (i = 0; i < cp->hash; i++) {
-		err = tcf_exts_init(&cp->perfect[i].exts, net,
-				    TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
-		if (err < 0)
-			goto errout;
-		cp->perfect[i].p = cp;
-	}
-
-	return 0;
-
-errout:
-	tcindex_free_perfect_hash(cp);
-	return err;
-}
-
-static int
-tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
-		  u32 handle, struct tcindex_data *p,
-		  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;
-	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;
-
-	err = tcf_exts_init(&e, net, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
-	if (err < 0)
-		return err;
-	err = tcf_exts_validate(net, tp, tb, est, &e, flags, extack);
-	if (err < 0)
-		goto errout;
-
-	err = -ENOMEM;
-	/* tcindex_data attributes must look atomic to classifier/lookup so
-	 * allocate new tcindex data and RCU assign it onto root. Keeping
-	 * perfect hash and hash pointers from old data.
-	 */
-	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
-	if (!cp)
-		goto errout;
-
-	cp->mask = p->mask;
-	cp->shift = p->shift;
-	cp->hash = p->hash;
-	cp->alloc_hash = p->alloc_hash;
-	cp->fall_through = p->fall_through;
-	cp->tp = tp;
-	refcount_set(&cp->refcnt, 1); /* Paired with tcindex_destroy_work() */
-
-	if (tb[TCA_TCINDEX_HASH])
-		cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
-
-	if (tb[TCA_TCINDEX_MASK])
-		cp->mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
-
-	if (tb[TCA_TCINDEX_SHIFT]) {
-		cp->shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
-		if (cp->shift > 16) {
-			err = -EINVAL;
-			goto errout;
-		}
-	}
-	if (!cp->hash) {
-		/* Hash not specified, use perfect hash if the upper limit
-		 * of the hashing index is below the threshold.
-		 */
-		if ((cp->mask >> cp->shift) < PERFECT_HASH_THRESHOLD)
-			cp->hash = (cp->mask >> cp->shift) + 1;
-		else
-			cp->hash = DEFAULT_HASH_SIZE;
-	}
-
-	if (p->perfect) {
-		int i;
-
-		if (tcindex_alloc_perfect_hash(net, cp) < 0)
-			goto errout;
-		cp->alloc_hash = cp->hash;
-		for (i = 0; i < min(cp->hash, p->hash); i++)
-			cp->perfect[i].res = p->perfect[i].res;
-		balloc = 1;
-	}
-	cp->h = p->h;
-
-	err = tcindex_filter_result_init(&new_filter_result, cp, net);
-	if (err < 0)
-		goto errout_alloc;
-	if (r)
-		cr = r->res;
-
-	err = -EBUSY;
-
-	/* Hash already allocated, make sure that we still meet the
-	 * requirements for the allocated hash.
-	 */
-	if (cp->perfect) {
-		if (!valid_perfect_hash(cp) ||
-		    cp->hash > cp->alloc_hash)
-			goto errout_alloc;
-	} else if (cp->h && cp->hash != cp->alloc_hash) {
-		goto errout_alloc;
-	}
-
-	err = -EINVAL;
-	if (tb[TCA_TCINDEX_FALL_THROUGH])
-		cp->fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
-
-	if (!cp->perfect && !cp->h)
-		cp->alloc_hash = cp->hash;
-
-	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
-	 * but then, we'd fail handles that may become valid after some future
-	 * mask change. While this is extremely unlikely to ever matter,
-	 * the check below is safer (and also more backwards-compatible).
-	 */
-	if (cp->perfect || valid_perfect_hash(cp))
-		if (handle >= cp->alloc_hash)
-			goto errout_alloc;
-
-
-	err = -ENOMEM;
-	if (!cp->perfect && !cp->h) {
-		if (valid_perfect_hash(cp)) {
-			if (tcindex_alloc_perfect_hash(net, cp) < 0)
-				goto errout_alloc;
-			balloc = 1;
-		} else {
-			struct tcindex_filter __rcu **hash;
-
-			hash = kcalloc(cp->hash,
-				       sizeof(struct tcindex_filter *),
-				       GFP_KERNEL);
-
-			if (!hash)
-				goto errout_alloc;
-
-			cp->h = hash;
-			balloc = 2;
-		}
-	}
-
-	if (cp->perfect)
-		r = cp->perfect + handle;
-	else
-		r = tcindex_lookup(cp, handle) ? : &new_filter_result;
-
-	if (r == &new_filter_result) {
-		f = kzalloc(sizeof(*f), GFP_KERNEL);
-		if (!f)
-			goto errout_alloc;
-		f->key = handle;
-		f->next = NULL;
-		err = tcindex_filter_result_init(&f->result, cp, net);
-		if (err < 0) {
-			kfree(f);
-			goto errout_alloc;
-		}
-	}
-
-	if (tb[TCA_TCINDEX_CLASSID]) {
-		cr.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
-		tcf_bind_filter(tp, &cr, base);
-	}
-
-	oldp = p;
-	r->res = cr;
-	tcf_exts_change(&r->exts, &e);
-
-	rcu_assign_pointer(tp->root, cp);
-
-	if (r == &new_filter_result) {
-		struct tcindex_filter *nfp;
-		struct tcindex_filter __rcu **fp;
-
-		f->result.res = r->res;
-		tcf_exts_change(&f->result.exts, &r->exts);
-
-		fp = cp->h + (handle % cp->hash);
-		for (nfp = rtnl_dereference(*fp);
-		     nfp;
-		     fp = &nfp->next, nfp = rtnl_dereference(*fp))
-				; /* nothing */
-
-		rcu_assign_pointer(*fp, f);
-	} else {
-		tcf_exts_destroy(&new_filter_result.exts);
-	}
-
-	if (oldp)
-		tcf_queue_work(&oldp->rwork, tcindex_partial_destroy_work);
-	return 0;
-
-errout_alloc:
-	if (balloc == 1)
-		tcindex_free_perfect_hash(cp);
-	else if (balloc == 2)
-		kfree(cp->h);
-	tcf_exts_destroy(&new_filter_result.exts);
-errout:
-	kfree(cp);
-	tcf_exts_destroy(&e);
-	return err;
-}
-
-static int
-tcindex_change(struct net *net, struct sk_buff *in_skb,
-	       struct tcf_proto *tp, unsigned long base, u32 handle,
-	       struct nlattr **tca, void **arg, u32 flags,
-	       struct netlink_ext_ack *extack)
-{
-	struct nlattr *opt = tca[TCA_OPTIONS];
-	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	struct tcindex_filter_result *r = *arg;
-	int err;
-
-	pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
-	    "p %p,r %p,*arg %p\n",
-	    tp, handle, tca, arg, opt, p, r, *arg);
-
-	if (!opt)
-		return 0;
-
-	err = nla_parse_nested_deprecated(tb, TCA_TCINDEX_MAX, opt,
-					  tcindex_policy, NULL);
-	if (err < 0)
-		return err;
-
-	return tcindex_set_parms(net, tp, base, handle, p, r, tb,
-				 tca[TCA_RATE], flags, extack);
-}
-
-static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker,
-			 bool rtnl_held)
-{
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	struct tcindex_filter *f, *next;
-	int i;
-
-	pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
-	if (p->perfect) {
-		for (i = 0; i < p->hash; i++) {
-			if (!p->perfect[i].res.class)
-				continue;
-			if (!tc_cls_stats_dump(tp, walker, p->perfect + i))
-				return;
-		}
-	}
-	if (!p->h)
-		return;
-	for (i = 0; i < p->hash; i++) {
-		for (f = rtnl_dereference(p->h[i]); f; f = next) {
-			next = rtnl_dereference(f->next);
-			if (!tc_cls_stats_dump(tp, walker, &f->result))
-				return;
-		}
-	}
-}
-
-static void tcindex_destroy(struct tcf_proto *tp, bool rtnl_held,
-			    struct netlink_ext_ack *extack)
-{
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	int i;
-
-	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
-
-	if (p->perfect) {
-		for (i = 0; i < p->hash; i++) {
-			struct tcindex_filter_result *r = p->perfect + i;
-
-			/* tcf_queue_work() does not guarantee the ordering we
-			 * want, so we have to take this refcnt temporarily to
-			 * ensure 'p' is freed after all tcindex_filter_result
-			 * here. Imperfect hash does not need this, because it
-			 * uses linked lists rather than an array.
-			 */
-			tcindex_data_get(p);
-
-			tcf_unbind_filter(tp, &r->res);
-			if (tcf_exts_get_net(&r->exts))
-				tcf_queue_work(&r->rwork,
-					       tcindex_destroy_rexts_work);
-			else
-				__tcindex_destroy_rexts(r);
-		}
-	}
-
-	for (i = 0; p->h && i < p->hash; i++) {
-		struct tcindex_filter *f, *next;
-		bool last;
-
-		for (f = rtnl_dereference(p->h[i]); f; f = next) {
-			next = rtnl_dereference(f->next);
-			tcindex_delete(tp, &f->result, &last, rtnl_held, NULL);
-		}
-	}
-
-	tcf_queue_work(&p->rwork, tcindex_destroy_work);
-}
-
-
-static int tcindex_dump(struct net *net, struct tcf_proto *tp, void *fh,
-			struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
-{
-	struct tcindex_data *p = rtnl_dereference(tp->root);
-	struct tcindex_filter_result *r = fh;
-	struct nlattr *nest;
-
-	pr_debug("tcindex_dump(tp %p,fh %p,skb %p,t %p),p %p,r %p\n",
-		 tp, fh, skb, t, p, r);
-	pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
-
-	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
-	if (nest == NULL)
-		goto nla_put_failure;
-
-	if (!fh) {
-		t->tcm_handle = ~0; /* whatever ... */
-		if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) ||
-		    nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) ||
-		    nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) ||
-		    nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
-			goto nla_put_failure;
-		nla_nest_end(skb, nest);
-	} else {
-		if (p->perfect) {
-			t->tcm_handle = r - p->perfect;
-		} else {
-			struct tcindex_filter *f;
-			struct tcindex_filter __rcu **fp;
-			int i;
-
-			t->tcm_handle = 0;
-			for (i = 0; !t->tcm_handle && i < p->hash; i++) {
-				fp = &p->h[i];
-				for (f = rtnl_dereference(*fp);
-				     !t->tcm_handle && f;
-				     fp = &f->next, f = rtnl_dereference(*fp)) {
-					if (&f->result == r)
-						t->tcm_handle = f->key;
-				}
-			}
-		}
-		pr_debug("handle = %d\n", t->tcm_handle);
-		if (r->res.class &&
-		    nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
-			goto nla_put_failure;
-
-		if (tcf_exts_dump(skb, &r->exts) < 0)
-			goto nla_put_failure;
-		nla_nest_end(skb, nest);
-
-		if (tcf_exts_dump_stats(skb, &r->exts) < 0)
-			goto nla_put_failure;
-	}
-
-	return skb->len;
-
-nla_put_failure:
-	nla_nest_cancel(skb, nest);
-	return -1;
-}
-
-static void tcindex_bind_class(void *fh, u32 classid, unsigned long cl,
-			       void *q, unsigned long base)
-{
-	struct tcindex_filter_result *r = fh;
-
-	tc_cls_bind_class(classid, cl, q, &r->res, base);
-}
-
-static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
-	.kind		=	"tcindex",
-	.classify	=	tcindex_classify,
-	.init		=	tcindex_init,
-	.destroy	=	tcindex_destroy,
-	.get		=	tcindex_get,
-	.change		=	tcindex_change,
-	.delete		=	tcindex_delete,
-	.walk		=	tcindex_walk,
-	.dump		=	tcindex_dump,
-	.bind_class	=	tcindex_bind_class,
-	.owner		=	THIS_MODULE,
-};
-
-static int __init init_tcindex(void)
-{
-	return register_tcf_proto_ops(&cls_tcindex_ops);
-}
-
-static void __exit exit_tcindex(void)
-{
-	unregister_tcf_proto_ops(&cls_tcindex_ops);
-}
-
-module_init(init_tcindex)
-module_exit(exit_tcindex)
-MODULE_LICENSE("GPL");

tools/testing/selftests/tc-testing/tc-tests/filters/tcindex.json

-[
-    {
-        "id": "8293",
-        "name": "Add tcindex filter with default action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref 1 tcindex chain 0 handle 0x0001 classid 1:1",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "7281",
-        "name": "Add tcindex filter with hash size and pass action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex hash 32 fall_through classid 1:1 action pass",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref.*tcindex chain [0-9]+ handle 0x0001 classid 1:1.*action order [0-9]+: gact action pass",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "b294",
-        "name": "Add tcindex filter with mask shift and reclassify action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex hash 32 mask 1 shift 2 fall_through classid 1:1 action reclassify",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref.*tcindex chain [0-9]+ handle 0x0001 classid 1:1.*action order [0-9]+: gact action reclassify",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "0532",
-        "name": "Add tcindex filter with pass_on and continue actions",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex hash 32 mask 1 shift 2 pass_on classid 1:1 action continue",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref.*tcindex chain [0-9]+ handle 0x0001 classid 1:1.*action order [0-9]+: gact action continue",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "d473",
-        "name": "Add tcindex filter with pipe action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex hash 32 mask 1 shift 2 fall_through classid 1:1 action pipe",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref.*tcindex chain [0-9]+ handle 0x0001 classid 1:1.*action order [0-9]+: gact action pipe",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "2940",
-        "name": "Add tcindex filter with miltiple actions",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress"
-        ],
-        "cmdUnderTest": "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 7 tcindex hash 32 mask 1 shift 2 fall_through classid 1:1 action skbedit mark 7 pipe action gact drop",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 7 protocol ip tcindex",
-        "matchPattern": "^filter parent ffff: protocol ip pref 7 tcindex.*handle 0x0001.*action.*skbedit.*mark 7 pipe.*action.*gact action drop",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "1893",
-        "name": "List tcindex filters",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress",
-            "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1",
-            "$TC filter add dev $DEV1 parent ffff: handle 2 protocol ip prio 1 tcindex classid 1:1"
-        ],
-        "cmdUnderTest": "$TC filter show dev $DEV1 parent ffff:",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter show dev $DEV1 parent ffff:",
-        "matchPattern": "handle 0x000[0-9]+ classid 1:1",
-        "matchCount": "2",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "2041",
-        "name": "Change tcindex filter with pass action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress",
-            "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action drop"
-        ],
-        "cmdUnderTest": "$TC filter change dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action pass",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "handle 0x0001 classid 1:1.*action order [0-9]+: gact action pass",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "9203",
-        "name": "Replace tcindex filter with pass action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress",
-            "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action drop"
-        ],
-        "cmdUnderTest": "$TC filter replace dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action pass",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "handle 0x0001 classid 1:1.*action order [0-9]+: gact action pass",
-        "matchCount": "1",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    },
-    {
-        "id": "7957",
-        "name": "Delete tcindex filter with drop action",
-        "category": [
-            "filter",
-            "tcindex"
-        ],
-        "plugins": {
-            "requires": "nsPlugin"
-        },
-        "setup": [
-            "$TC qdisc add dev $DEV1 ingress",
-            "$TC filter add dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action drop"
-        ],
-        "cmdUnderTest": "$TC filter del dev $DEV1 parent ffff: handle 1 protocol ip prio 1 tcindex classid 1:1 action drop",
-        "expExitCode": "0",
-        "verifyCmd": "$TC filter get dev $DEV1 parent ffff: handle 1 prio 1 protocol ip tcindex",
-        "matchPattern": "handle 0x0001 classid 1:1.*action order [0-9]+: gact action drop",
-        "matchCount": "0",
-        "teardown": [
-            "$TC qdisc del dev $DEV1 ingress"
-        ]
-    }
-]