linux/net/tipc/node.c, branch v5.8

Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"

2020-06-02T22:13:46Z

This reverts commit de058420767df21e2b6b0f3bb36d1616fb962032. There is no actual tipc_node refcnt leak as stated in the above commit. The refcnt is hold carefully for the case of an asynchronous decryption (i.e. -EINPROGRESS/-EBUSY and skb = NULL is returned), so that the node object cannot be freed in the meantime. The counter will be re-balanced when the operation's callback arrives with the decrypted buffer if any. In other cases, e.g. a synchronous crypto the counter will be decreased immediately when it is done. Now with that commit, a kernel panic will occur when there is no node found (i.e. n = NULL) in the 'tipc_rcv()' or a premature release of the node object. This commit solves the issues by reverting the said commit, but keeping one valid case that the 'skb_linearize()' is failed. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Tested-by: Hoang Le Signed-off-by: David S. Miller

tipc: add support for broadcast rcv stats dumping

2020-05-26T22:16:52Z

This commit enables dumping the statistics of a broadcast-receiver link like the traditional 'broadcast-link' one (which is for broadcast- sender). The link dumping can be triggered via netlink (e.g. the iproute2/tipc tool) by the link flag - 'TIPC_NLA_LINK_BROADCAST' as the indicator. The name of a broadcast-receiver link of a specific peer will be in the format: 'broadcast-link:'. For example: Link Window:50 packets RX packets:7841 fragments:2408/440 bundles:0/0 TX packets:0 fragments:0/0 bundles:0/0 RX naks:0 defs:124 dups:0 TX naks:21 acks:0 retrans:0 Congestion link:0 Send queue max:0 avg:0 In addition, the broadcast-receiver link statistics can be reset in the usual way via netlink by specifying that link name in command. Note: the 'tipc_link_name_ext()' is removed because the link name can now be retrieved simply via the 'l->name'. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: enable broadcast retrans via unicast

2020-05-26T22:16:52Z

In some environment, broadcast traffic is suppressed at high rate (i.e. a kind of bandwidth limit setting). When it is applied, TIPC broadcast can still run successfully. However, when it comes to a high load, some packets will be dropped first and TIPC tries to retransmit them but the packet retransmission is intentionally broadcast too, so making things worse and not helpful at all. This commit enables the broadcast retransmission via unicast which only retransmits packets to the specific peer that has really reported a gap i.e. not broadcasting to all nodes in the cluster, so will prevent from being suppressed, and also reduce some overheads on the other peers due to duplicates, finally improve the overall TIPC broadcast performance. Note: the functionality can be turned on/off via the sysctl file: echo 1 > /proc/sys/net/tipc/bc_retruni echo 0 > /proc/sys/net/tipc/bc_retruni Default is '0', i.e. the broadcast retransmission still works as usual. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: introduce Gap ACK blocks for broadcast link

2020-05-26T22:16:52Z

As achieved through commit 9195948fbf34 ("tipc: improve TIPC throughput by Gap ACK blocks"), we apply the same mechanism for the broadcast link as well. The 'Gap ACK blocks' data field in a 'PROTOCOL/STATE_MSG' will consist of two parts built for both the broadcast and unicast types: 31 16 15 0 +-------------+-------------+-------------+-------------+ | bgack_cnt | ugack_cnt | len | +-------------+-------------+-------------+-------------+ - | gap | ack | | +-------------+-------------+-------------+-------------+ > bc gacks : : : | +-------------+-------------+-------------+-------------+ - | gap | ack | | +-------------+-------------+-------------+-------------+ > uc gacks : : : | +-------------+-------------+-------------+-------------+ - which is "automatically" backward-compatible. We also increase the max number of Gap ACK blocks to 128, allowing upto 64 blocks per type (total buffer size = 516 bytes). Besides, the 'tipc_link_advance_transmq()' function is refactored which is applicable for both the unicast and broadcast cases now, so some old functions can be removed and the code is optimized. With the patch, TIPC broadcast is more robust regardless of packet loss or disorder, latency, ... in the underlying network. Its performance is boost up significantly. For example, experiment with a 5% packet loss rate results: $ time tipc-pipe --mc --rdm --data_size 123 --data_num 1500000 real 0m 42.46s user 0m 1.16s sys 0m 17.67s Without the patch: $ time tipc-pipe --mc --rdm --data_size 123 --data_num 1500000 real 8m 27.94s user 0m 0.55s sys 0m 2.38s Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: Fix potential tipc_node refcnt leak in tipc_rcv

2020-04-18T20:24:20Z

tipc_rcv() invokes tipc_node_find() twice, which returns a reference of the specified tipc_node object to "n" with increased refcnt. When tipc_rcv() returns or a new object is assigned to "n", the original local reference of "n" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in some paths of tipc_rcv(), which forget to decrease the refcnt increased by tipc_node_find() and will cause a refcnt leak. Fix this issue by calling tipc_node_put() before the original object pointed by "n" becomes invalid. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: David S. Miller

tipc: Add a missing case of TIPC_DIRECT_MSG type

2020-03-26T18:21:02Z

In the commit f73b12812a3d ("tipc: improve throughput between nodes in netns"), we're missing a check to handle TIPC_DIRECT_MSG type, it's still using old sending mechanism for this message type. So, throughput improvement is not significant as expected. Besides that, when sending a large message with that type, we're also handle wrong receiving queue, it should be enqueued in socket receiving instead of multicast messages. Fix this by adding the missing case for TIPC_DIRECT_MSG. Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Reported-by: Tuong Lien Signed-off-by: Hoang Le Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: make three functions static

2020-02-10T09:23:00Z

Fix the following sparse warning: net/tipc/node.c:281:6: warning: symbol 'tipc_node_free' was not declared. Should it be static? net/tipc/node.c:2801:5: warning: symbol '__tipc_nl_node_set_key' was not declared. Should it be static? net/tipc/node.c:2878:5: warning: symbol '__tipc_nl_node_flush_key' was not declared. Should it be static? Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Fixes: e1f32190cf7d ("tipc: add support for AEAD key setting via netlink") Signed-off-by: Chen Wandun Signed-off-by: David S. Miller

tipc: introduce variable window congestion control

2019-12-11T01:31:15Z

We introduce a simple variable window congestion control for links. The algorithm is inspired by the Reno algorithm, covering both 'slow start', 'congestion avoidance', and 'fast recovery' modes. - We introduce hard lower and upper window limits per link, still different and configurable per bearer type. - We introduce a 'slow start theshold' variable, initially set to the maximum window size. - We let a link start at the minimum congestion window, i.e. in slow start mode, and then let is grow rapidly (+1 per rceived ACK) until it reaches the slow start threshold and enters congestion avoidance mode. - In congestion avoidance mode we increment the congestion window for each window-size number of acked packets, up to a possible maximum equal to the configured maximum window. - For each non-duplicate NACK received, we drop back to fast recovery mode, by setting the both the slow start threshold to and the congestion window to (current_congestion_window / 2). - If the timeout handler finds that the transmit queue has not moved since the previous timeout, it drops the link back to slow start and forces a probe containing the last sent sequence number to the sent to the peer, so that this can discover the stale situation. This change does in reality have effect only on unicast ethernet transport, as we have seen that there is no room whatsoever for increasing the window max size for the UDP bearer. For now, we also choose to keep the limits for the broadcast link unchanged and equal. This algorithm seems to give a 50-100% throughput improvement for messages larger than MTU. Suggested-by: Xin Long Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: update replicast capability for broadcast send link

2019-11-22T17:29:50Z

When setting up a cluster with non-replicast/replicast capability supported. This capability will be disabled for broadcast send link in order to be backwards compatible. However, when these non-support nodes left and be removed out the cluster. We don't update this capability on broadcast send link. Then, some of features that based on this capability will also disabling as unexpected. In this commit, we make sure the broadcast send link capabilities will be re-calculated as soon as a node removed/rejoined a cluster. Acked-by: Jon Maloy Signed-off-by: Hoang Le Signed-off-by: David S. Miller

tipc: add support for AEAD key setting via netlink

2019-11-08T22:01:59Z

This commit adds two netlink commands to TIPC in order for user to be able to set or remove AEAD keys: - TIPC_NL_KEY_SET - TIPC_NL_KEY_FLUSH When the 'KEY_SET' is given along with the key data, the key will be initiated and attached to TIPC crypto. On the other hand, the 'KEY_FLUSH' command will remove all existing keys if any. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller