diff options
author | Jeremy Kerr <jk@codeconstruct.com.au> | 2021-09-29 09:26:09 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-09-29 12:00:11 +0200 |
commit | 7b14e15ae6f4850392800482efb54d5cf4ae300c (patch) | |
tree | 4857420af83ce1abaa4ff581b31303fcc5c5c109 /net/mctp | |
parent | mctp: Add refcounts to mctp_dev (diff) | |
download | linux-7b14e15ae6f4850392800482efb54d5cf4ae300c.tar.xz linux-7b14e15ae6f4850392800482efb54d5cf4ae300c.zip |
mctp: Implement a timeout for tags
Currently, a MCTP (local-eid,remote-eid,tag) tuple is allocated to a
socket on send, and only expires when the socket is closed.
This change introduces a tag timeout, freeing the tuple after a fixed
expiry - currently six seconds. This is greater than (but close to) the
max response timeout in upper-layer bindings.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mctp')
-rw-r--r-- | net/mctp/af_mctp.c | 44 | ||||
-rw-r--r-- | net/mctp/route.c | 8 |
2 files changed, 52 insertions, 0 deletions
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c index 2767d548736b..46e5ede385cb 100644 --- a/net/mctp/af_mctp.c +++ b/net/mctp/af_mctp.c @@ -223,16 +223,60 @@ static const struct proto_ops mctp_dgram_ops = { .sendpage = sock_no_sendpage, }; +static void mctp_sk_expire_keys(struct timer_list *timer) +{ + struct mctp_sock *msk = container_of(timer, struct mctp_sock, + key_expiry); + struct net *net = sock_net(&msk->sk); + unsigned long next_expiry, flags; + struct mctp_sk_key *key; + struct hlist_node *tmp; + bool next_expiry_valid = false; + + spin_lock_irqsave(&net->mctp.keys_lock, flags); + + hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) { + spin_lock(&key->lock); + + if (!time_after_eq(key->expiry, jiffies)) { + key->valid = false; + hlist_del_rcu(&key->hlist); + hlist_del_rcu(&key->sklist); + spin_unlock(&key->lock); + mctp_key_unref(key); + continue; + } + + if (next_expiry_valid) { + if (time_before(key->expiry, next_expiry)) + next_expiry = key->expiry; + } else { + next_expiry = key->expiry; + next_expiry_valid = true; + } + spin_unlock(&key->lock); + } + + spin_unlock_irqrestore(&net->mctp.keys_lock, flags); + + if (next_expiry_valid) + mod_timer(timer, next_expiry); +} + static int mctp_sk_init(struct sock *sk) { struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk); INIT_HLIST_HEAD(&msk->keys); + timer_setup(&msk->key_expiry, mctp_sk_expire_keys, 0); return 0; } static void mctp_sk_close(struct sock *sk, long timeout) { + struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk); + + del_timer_sync(&msk->key_expiry); sk_common_release(sk); } diff --git a/net/mctp/route.c b/net/mctp/route.c index 37aa67847a5a..c342adf4f97f 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -24,6 +24,8 @@ #include <net/sock.h> static const unsigned int mctp_message_maxlen = 64 * 1024; +static const unsigned long mctp_key_lifetime = 6 * CONFIG_HZ; + /* route output callbacks */ static int mctp_route_discard(struct mctp_route *route, struct sk_buff *skb) @@ -175,6 +177,9 @@ static int mctp_key_add(struct mctp_sk_key *key, struct mctp_sock *msk) if (!rc) { refcount_inc(&key->refs); + key->expiry = jiffies + mctp_key_lifetime; + timer_reduce(&msk->key_expiry, key->expiry); + hlist_add_head(&key->hlist, &net->mctp.keys); hlist_add_head(&key->sklist, &msk->keys); } @@ -497,6 +502,9 @@ static void mctp_reserve_tag(struct net *net, struct mctp_sk_key *key, lockdep_assert_held(&mns->keys_lock); + key->expiry = jiffies + mctp_key_lifetime; + timer_reduce(&msk->key_expiry, key->expiry); + /* we hold the net->key_lock here, allowing updates to both * then net and sk */ |