From 2a57f182420174c7fd4b19db979a2d135231a963 Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 6 Jul 2018 20:10:03 +0200 Subject: tipc: fix wrong return value from function tipc_node_try_addr() The function for checking if there is an node address conflict is supposed to return a suggestion for a new address if it finds a conflict, and zero otherwise. But in case the peer being checked is previously unknown it does instead return a "suggestion" for the checked address itself. This results in a DSC_TRIAL_FAIL_MSG being sent unecessarily to the peer, and sometimes makes the trial period starting over again. Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values") Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/node.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'net/tipc') diff --git a/net/tipc/node.c b/net/tipc/node.c index 6a44eb812baf..0453bd451ce8 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -797,6 +797,7 @@ static u32 tipc_node_suggest_addr(struct net *net, u32 addr) } /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not + * Returns suggested address if any, otherwise 0 */ u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr) { @@ -819,12 +820,14 @@ u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr) if (n) { addr = n->addr; tipc_node_put(n); + return addr; } - /* Even this node may be in trial phase */ + + /* Even this node may be in conflict */ if (tn->trial_addr == addr) return tipc_node_suggest_addr(net, addr); - return addr; + return 0; } void tipc_node_check_dest(struct net *net, u32 addr, -- cgit v1.2.3 From e415577f57f4452150642500364cbe5fa6112813 Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 6 Jul 2018 20:10:04 +0200 Subject: tipc: correct discovery message handling during address trial period With the duplicate address discovery protocol for tipc nodes addresses we introduced a one second trial period before a node is allocated a hash number to use as address. Unfortunately, we miss to handle the case when a regular LINK REQUEST/ RESPONSE arrives from a cluster node during the trial period. Such messages are not ignored as they should be, leading to links setup attempts while the node still has no address. Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values") Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/discover.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/tipc') diff --git a/net/tipc/discover.c b/net/tipc/discover.c index 9f666e0650e2..dcadc10dffd1 100644 --- a/net/tipc/discover.c +++ b/net/tipc/discover.c @@ -133,6 +133,8 @@ static void disc_dupl_alert(struct tipc_bearer *b, u32 node_addr, } /* tipc_disc_addr_trial(): - handle an address uniqueness trial from peer + * Returns true if message should be dropped by caller, i.e., if it is a + * trial message or we are inside trial period. Otherwise false. */ static bool tipc_disc_addr_trial_msg(struct tipc_discoverer *d, struct tipc_media_addr *maddr, @@ -168,8 +170,9 @@ static bool tipc_disc_addr_trial_msg(struct tipc_discoverer *d, msg_set_type(buf_msg(d->skb), DSC_REQ_MSG); } + /* Accept regular link requests/responses only after trial period */ if (mtyp != DSC_TRIAL_MSG) - return false; + return trial; sugg_addr = tipc_node_try_addr(net, peer_id, src); if (sugg_addr) -- cgit v1.2.3 From 92018c7ca959ccd346d6235dac03cf7fc1ba51f7 Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 6 Jul 2018 20:10:05 +0200 Subject: tipc: fix correct setting of message type in second discoverer The duplicate address discovery protocol is not safe against two discoverers running in parallel. The one executing first after the trial period is over will set the node address and change its own message type to DSC_REQ_MSG. The one executing last may find that the node address is already set, and never change message type, with the result that its links may never be established. In this commmit we ensure that the message type always is set correctly after the trial period is over. Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values") Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/discover.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'net/tipc') diff --git a/net/tipc/discover.c b/net/tipc/discover.c index dcadc10dffd1..2830709957bd 100644 --- a/net/tipc/discover.c +++ b/net/tipc/discover.c @@ -287,7 +287,6 @@ static void tipc_disc_timeout(struct timer_list *t) { struct tipc_discoverer *d = from_timer(d, t, timer); struct tipc_net *tn = tipc_net(d->net); - u32 self = tipc_own_addr(d->net); struct tipc_media_addr maddr; struct sk_buff *skb = NULL; struct net *net = d->net; @@ -301,12 +300,14 @@ static void tipc_disc_timeout(struct timer_list *t) goto exit; } - /* Did we just leave the address trial period ? */ - if (!self && !time_before(jiffies, tn->addr_trial_end)) { - self = tn->trial_addr; - tipc_net_finalize(net, self); - msg_set_prevnode(buf_msg(d->skb), self); + /* Trial period over ? */ + if (!time_before(jiffies, tn->addr_trial_end)) { + /* Did we just leave it ? */ + if (!tipc_own_addr(net)) + tipc_net_finalize(net, tn->trial_addr); + msg_set_type(buf_msg(d->skb), DSC_REQ_MSG); + msg_set_prevnode(buf_msg(d->skb), tipc_own_addr(net)); } /* Adjust timeout interval according to discovery phase */ -- cgit v1.2.3 From 9faa89d4ed9d7d326f4763d262842270450f9b1f Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 6 Jul 2018 20:10:06 +0200 Subject: tipc: make function tipc_net_finalize() thread safe The setting of the node address is not thread safe, meaning that two discoverers may decide to set it simultanously, with a duplicate entry in the name table as result. We fix that with this commit. Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values") Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/net.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'net/tipc') diff --git a/net/tipc/net.c b/net/tipc/net.c index 4fbaa0464405..a7f6964c3a4b 100644 --- a/net/tipc/net.c +++ b/net/tipc/net.c @@ -121,12 +121,17 @@ int tipc_net_init(struct net *net, u8 *node_id, u32 addr) void tipc_net_finalize(struct net *net, u32 addr) { - tipc_set_node_addr(net, addr); - smp_mb(); - tipc_named_reinit(net); - tipc_sk_reinit(net); - tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr, - TIPC_CLUSTER_SCOPE, 0, addr); + struct tipc_net *tn = tipc_net(net); + + spin_lock_bh(&tn->node_list_lock); + if (!tipc_own_addr(net)) { + tipc_set_node_addr(net, addr); + tipc_named_reinit(net); + tipc_sk_reinit(net); + tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr, + TIPC_CLUSTER_SCOPE, 0, addr); + } + spin_unlock_bh(&tn->node_list_lock); } void tipc_net_stop(struct net *net) -- cgit v1.2.3