diff options
| author | Jiri Pirko <jiri@mellanox.com> | 2018-02-13 12:00:17 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-02-13 12:29:02 -0500 |
| commit | 339c21d7c459238135d87da8fefbfd25d98bc375 (patch) | |
| tree | 1c8eebd7b5da3e11d1374fe328dc4c254f47d4be /net/sched | |
| parent | bb047ddd145860ff24820320a21f03cf8c071b22 (diff) | |
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: Paweł Staszewski <pstaszewski@itcare.pl>
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Fixes: 7fa9d974f3c2 ("net: sched: cls_u32: use block instead of q in tc_u_common")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/cls_u32.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index 6c7601a530e3..ed8b6a24b9e9 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -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); |