wireguard-linux/net/rxrpc/local_object.c, branch jd/orphan-parallel

rxrpc: Rewrite the client connection manager

2020-09-08T20:11:43Z

Rewrite the rxrpc client connection manager so that it can support multiple connections for a given security key to a peer. The following changes are made: (1) For each open socket, the code currently maintains an rbtree with the connections placed into it, keyed by communications parameters. This is tricky to maintain as connections can be culled from the tree or replaced within it. Connections can require replacement for a number of reasons, e.g. their IDs span too great a range for the IDR data type to represent efficiently, the call ID numbers on that conn would overflow or the conn got aborted. This is changed so that there's now a connection bundle object placed in the tree, keyed on the same parameters. The bundle, however, does not need to be replaced. (2) An rxrpc_bundle object can now manage the available channels for a set of parallel connections. The lock that manages this is moved there from the rxrpc_connection struct (channel_lock). (3) There'a a dummy bundle for all incoming connections to share so that they have a channel_lock too. It might be better to give each incoming connection its own bundle. This bundle is not needed to manage which channels incoming calls are made on because that's the solely at whim of the client. (4) The restrictions on how many client connections are around are removed. Instead, a previous patch limits the number of client calls that can be allocated. Ordinarily, client connections are reaped after 2 minutes on the idle queue, but when more than a certain number of connections are in existence, the reaper starts reaping them after 2s of idleness instead to get the numbers back down. It could also be made such that new call allocations are forced to wait until the number of outstanding connections subsides. Signed-off-by: David Howells

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59Z

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

ipv6: add ip6_sock_set_recverr

2020-05-28T18:11:45Z

Add a helper to directly set the IPV6_RECVERR sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Reviewed-by: David Howells Signed-off-by: David S. Miller

ipv4: add ip_sock_set_mtu_discover

2020-05-28T18:11:45Z

Add a helper to directly set the IP_MTU_DISCOVER sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Reviewed-by: David Howells [rxrpc bits] Signed-off-by: David S. Miller

ipv4: add ip_sock_set_recverr

2020-05-28T18:11:45Z

Add a helper to directly set the IP_RECVERR sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig Reviewed-by: David Howells Signed-off-by: David S. Miller

net: add sock_enable_timestamps

2020-05-28T18:11:44Z

Add a helper to directly enable timestamps instead of setting the SO_TIMESTAMP* sockopts from kernel space and going through a fake uaccess. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

rxrpc: Fix DATA Tx to disable nofrag for UDP on AF_INET6 socket

2020-04-14T23:26:47Z

Fix the DATA packet transmission to disable nofrag for UDPv4 on an AF_INET6 socket as well as UDPv6 when trying to transmit fragmentably. Without this, packets filled to the normal size used by the kernel AFS client of 1412 bytes be rejected by udp_sendmsg() with EMSGSIZE immediately. The ->sk_error_report() notification hook is called, but rxrpc doesn't generate a trace for it. This is a temporary fix; a more permanent solution needs to involve changing the size of the packets being filled in accordance with the MTU, which isn't currently done in AF_RXRPC. The reason for not doing so was that, barring the last packet in an rx jumbo packet, jumbos can only be assembled out of 1412-byte packets - and the plan was to construct jumbos on the fly at transmission time. Also, there's no point turning on IPV6_MTU_DISCOVER, since IPv6 has to engage in this anyway since fragmentation is only done by the sender. We can then condense the switch-statement in rxrpc_send_data_packet(). Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support") Signed-off-by: David Howells Signed-off-by: David S. Miller

rxrpc: Fix missing active use pinning of rxrpc_local object

2020-01-30T21:50:41Z

The introduction of a split between the reference count on rxrpc_local objects and the usage count didn't quite go far enough. A number of kernel work items need to make use of the socket to perform transmission. These also need to get an active count on the local object to prevent the socket from being closed. Fix this by getting the active count in those places. Also split out the raw active count get/put functions as these places tend to hold refs on the rxrpc_local object already, so getting and putting an extra object ref is just a waste of time. The problem can lead to symptoms like: BUG: kernel NULL pointer dereference, address: 0000000000000018 .. CPU: 2 PID: 818 Comm: kworker/u9:0 Not tainted 5.5.0-fscache+ #51 ... RIP: 0010:selinux_socket_sendmsg+0x5/0x13 ... Call Trace: security_socket_sendmsg+0x2c/0x3e sock_sendmsg+0x1a/0x46 rxrpc_send_keepalive+0x131/0x1ae rxrpc_peer_keepalive_worker+0x219/0x34b process_one_work+0x18e/0x271 worker_thread+0x1a3/0x247 kthread+0xe6/0xeb ret_from_fork+0x1f/0x30 Fixes: 730c5fd42c1e ("rxrpc: Fix local endpoint refcounting") Signed-off-by: David Howells

rxrpc: Fix use-after-free in rxrpc_put_local()

2020-01-30T21:50:41Z

Fix rxrpc_put_local() to not access local->debug_id after calling atomic_dec_return() as, unless that returned n==0, we no longer have the right to access the object. Fixes: 06d9532fa6b3 ("rxrpc: Fix read-after-free in rxrpc_queue_local()") Signed-off-by: David Howells

rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up [ver #2]

2019-08-30T22:06:52Z

When a local endpoint is ceases to be in use, such as when the kafs module is unloaded, the kernel will emit an assertion failure if there are any outstanding client connections: rxrpc: Assertion failed ------------[ cut here ]------------ kernel BUG at net/rxrpc/local_object.c:433! and even beyond that, will evince other oopses if there are service connections still present. Fix this by: (1) Removing the triggering of connection reaping when an rxrpc socket is released. These don't actually clean up the connections anyway - and further, the local endpoint may still be in use through another socket. (2) Mark the local endpoint as dead when we start the process of tearing it down. (3) When destroying a local endpoint, strip all of its client connections from the idle list and discard the ref on each that the list was holding. (4) When destroying a local endpoint, call the service connection reaper directly (rather than through a workqueue) to immediately kill off all outstanding service connections. (5) Make the service connection reaper reap connections for which the local endpoint is marked dead. Only after destroying the connections can we close the socket lest we get an oops in a workqueue that's looking at a connection or a peer. Fixes: 3d18cbb7fd0c ("rxrpc: Fix conn expiry timers") Signed-off-by: David Howells Tested-by: Marc Dionne Signed-off-by: David S. Miller