Fix regression bug introduced in
commit 365ad353c256 ("tipc: reduce risk of user starvation during link
congestion")
Only signal -EDESTADDRREQ for RDM/DGRAM if we don't have a cached
sockaddr.
Fixes: 365ad353c256 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When sending multicast messages via blocking socket,
if sending link is congested (tsk->cong_link_cnt is set to 1),
the sending thread will be put into sleeping state. However,
tipc_sk_filter_rcv() is called under socket spin lock but
tipc_wait_for_cond() is not. So, there is no guarantee that
the setting of tsk->cong_link_cnt to 0 in tipc_sk_proto_rcv() in
CPU-1 will be perceived by CPU-0. If that is the case, the sending
thread in CPU-0 after being waken up, will continue to see
tsk->cong_link_cnt as 1 and put the sending thread into sleeping
state again. The sending thread will sleep forever.
CPU-0 | CPU-1
tipc_wait_for_cond() |
{ |
// condition_ = !tsk->cong_link_cnt |
while ((rc_ = !(condition_))) { |
... |
release_sock(sk_); |
wait_woken(); |
| if (!sock_owned_by_user(sk))
| tipc_sk_filter_rcv()
| {
| ...
| tipc_sk_proto_rcv()
| {
| ...
| tsk->cong_link_cnt--;
| ...
| sk->sk_write_space(sk);
| ...
| }
| ...
| }
sched_annotate_sleep(); |
lock_sock(sk_); |
remove_wait_queue(); |
} |
} |
This commit fixes it by adding memory barrier to tipc_sk_proto_rcv()
and tipc_wait_for_cond().
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Three conflicts, one of which, for marvell10g.c is non-trivial and requires some follow-up from Heiner or someone else. The issue is that Heiner converted the marvell10g driver over to use the generic c45 code as much as possible. However, in 'net' a bug fix appeared which makes sure that a new local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0 is cleared. Signed-off-by: David S. Miller <davem@davemloft.net>
This commit replaces schedule_timeout() with wait_woken() in function tipc_wait_for_rcvmsg(). wait_woken() uses memory barriers in its implementation to avoid potential race condition when putting a process into sleeping state and then waking it up. Acked-by: Ying Xue <ying.xue@windriver.com> Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 844cf763fba6 ("tipc: make macro tipc_wait_for_cond() smp safe")
replaced finish_wait() with remove_wait_queue() but still used
prepare_to_wait(). This causes unnecessary conditional
checking before adding to wait queue in prepare_to_wait().
This commit replaces prepare_to_wait() with add_wait_queue()
as the pair function with remove_wait_queue().
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netfilter conflicts were rather simple overlapping changes. However, the cls_tcindex.c stuff was a bit more complex. On the 'net' side, Cong is fixing several races and memory leaks. Whilst on the 'net-next' side we have Vlad adding the rtnl-ness support. What I've decided to do, in order to resolve this, is revert the conversion over to using a workqueue that Cong did, bringing us back to pure RCU. I did it this way because I believe that either Cong's races don't apply with have Vlad did things, or Cong will have to implement the race fix slightly differently. Signed-off-by: David S. Miller <davem@davemloft.net>
When a link endpoint is re-created (e.g. after a node reboot or interface reset), the link session number is varied by random, the peer endpoint will be synced with this new session number before the link is re-established. However, there is a shortcoming in this mechanism that can lead to the link never re-established or faced with a failure then. It happens when the peer endpoint is ready in ESTABLISHING state, the 'peer_session' as well as the 'in_session' flag have been set, but suddenly this link endpoint leaves. When it comes back with a random session number, there are two situations possible: 1/ If the random session number is larger than (or equal to) the previous one, the peer endpoint will be updated with this new session upon receipt of a RESET_MSG from this endpoint, and the link can be re- established as normal. Otherwise, all the RESET_MSGs from this endpoint will be rejected by the peer. In turn, when this link endpoint receives one ACTIVATE_MSG from the peer, it will move to ESTABLISHED and start to send STATE_MSGs, but again these messages will be dropped by the peer due to wrong session. The peer link endpoint can still become ESTABLISHED after receiving a traffic message from this endpoint (e.g. a BCAST_PROTOCOL or NAME_DISTRIBUTOR), but since all the STATE_MSGs are invalid, the link will be forced down sooner or later! Even in case the random session number is larger than the previous one, it can be that the ACTIVATE_MSG from the peer arrives first, and this link endpoint moves quickly to ESTABLISHED without sending out any RESET_MSG yet. Consequently, the peer link will not be updated with the new session number, and the same link failure scenario as above will happen. 2/ Another situation can be that, the peer link endpoint was reset due to any reasons in the meantime, its link state was set to RESET from ESTABLISHING but still in session, i.e. the 'in_session' flag is not reset... Now, if the random session number from this endpoint is less than the previous one, all the RESET_MSGs from this endpoint will be rejected by the peer. In the other direction, when this link endpoint receives a RESET_MSG from the peer, it moves to ESTABLISHING and starts to send ACTIVATE_MSGs, but all these messages will be rejected by the peer too. As a result, the link cannot be re-established but gets stuck with this link endpoint in state ESTABLISHING and the peer in RESET! Solution: =========== This link endpoint should not go directly to ESTABLISHED when getting ACTIVATE_MSG from the peer which may belong to the old session if the link was re-created. To ensure the session to be correct before the link is re-established, the peer endpoint in ESTABLISHING state will send back the last session number in ACTIVATE_MSG for a verification at this endpoint. Then, if needed, a new and more appropriate session number will be regenerated to force a re-synch first. In addition, when a link in ESTABLISHING state is reset, its state will move to RESET according to the link FSM, along with resetting the 'in_session' flag (and the other data) as a normal link reset, it will also be deleted if requested. The solution is backward compatible. Acked-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
When we free skb at tipc_data_input, we return a 'false' boolean. Then, skb passed to subcalling tipc_link_input in tipc_link_rcv, <snip> 1303 int tipc_link_rcv: ... 1354 if (!tipc_data_input(l, skb, l->inputq)) 1355 rc |= tipc_link_input(l, skb, l->inputq); </snip> Fix it by simple changing to a 'true' boolean when skb is being free-ed. Then, tipc_link_rcv will bypassed to subcalling tipc_link_input as above condition. Acked-by: Ying Xue <ying.xue@windriver.com> Acked-by: Jon Maloy <maloy@donjonn.com> Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
max_rcvbuf_size is no longer used since commit "414574a0af36". Signed-off-by: Zhaolong Zhang <zhangzl2013@126.com> Acked-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>