Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 339c21d7 authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
Browse files

net: sched: fix tc_u_common lookup 



The offending commit wrongly assumes 1:1 mapping between block and q.
However, there are multiple blocks for a single q for classful qdiscs.
Since the obscure tc_u_common sharing mechanism expects it to be shared
among a qdisc, fix it by storing q pointer in case the block is not
shared.

Reported-by: default avatarPaweł Staszewski <pstaszewski@itcare.pl>
Reported-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
Fixes: 7fa9d974 ("net: sched: cls_u32: use block instead of q in tc_u_common")
Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bb047ddd

net/sched/cls_u32.c

+20 −4
Original line number Diff line number Diff line
@@ -96,7 +96,7 @@ struct tc_u_hnode { 


struct tc_u_common {

	struct tc_u_hnode __rcu	*hlist;

	struct tcf_block	*block;

	void			*ptr;

	int			refcnt;

	struct idr		handle_idr;

	struct hlist_node	hnode;
@@ -330,9 +330,25 @@ static struct hlist_head *tc_u_common_hash; 
#define U32_HASH_SHIFT 10

#define U32_HASH_SIZE (1 << U32_HASH_SHIFT)



static void *tc_u_common_ptr(const struct tcf_proto *tp)

{

	struct tcf_block *block = tp->chain->block;



	/* The block sharing is currently supported only

	 * for classless qdiscs. In that case we use block

	 * for tc_u_common identification. In case the

	 * block is not shared, block->q is a valid pointer

	 * and we can use that. That works for classful qdiscs.

	 */

	if (tcf_block_shared(block))

		return block;

	else

		return block->q;

}



static unsigned int tc_u_hash(const struct tcf_proto *tp)

{

	return hash_ptr(tp->chain->block, U32_HASH_SHIFT);

	return hash_ptr(tc_u_common_ptr(tp), U32_HASH_SHIFT);

}



static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
@@ -342,7 +358,7 @@ static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp) 


	h = tc_u_hash(tp);

	hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) {

		if (tc->block == tp->chain->block)

		if (tc->ptr == tc_u_common_ptr(tp))

			return tc;

	}

	return NULL;
@@ -371,7 +387,7 @@ static int u32_init(struct tcf_proto *tp) 
			kfree(root_ht);

			return -ENOBUFS;

		}

		tp_c->block = tp->chain->block;

		tp_c->ptr = tc_u_common_ptr(tp);

		INIT_HLIST_NODE(&tp_c->hnode);

		idr_init(&tp_c->handle_idr);