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2023-01-06rxrpc: Move client call connection to the I/O threadGravatar David Howells 1-408/+125
Move the connection setup of client calls to the I/O thread so that a whole load of locking and barrierage can be eliminated. This necessitates the app thread waiting for connection to complete before it can begin encrypting data. This also completes the fix for a race that exists between call connection and call disconnection whereby the data transmission code adds the call to the peer error distribution list after the call has been disconnected (say by the rxrpc socket getting closed). The fix is to complete the process of moving call connection, data transmission and call disconnection into the I/O thread and thus forcibly serialising them. Note that the issue may predate the overhaul to an I/O thread model that were included in the merge window for v6.2, but the timing is very much changed by the change given below. Fixes: cf37b5987508 ("rxrpc: Move DATA transmission into call processor work item") Reported-by: syzbot+c22650d2844392afdcfd@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Move the client conn cache management to the I/O threadGravatar David Howells 1-60/+32
Move the management of the client connection cache to the I/O thread rather than managing it from the namespace as an aggregate across all the local endpoints within the namespace. This will allow a load of locking to be got rid of in a future patch as only the I/O thread will be looking at the this. The downside is that the total number of cached connections on the system can get higher because the limit is now per-local rather than per-netns. We can, however, keep the number of client conns in use across the entire netfs and use that to reduce the expiration time of idle connection. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Remove call->state_lockGravatar David Howells 1-6/+4
All the setters of call->state are now in the I/O thread and thus the state lock is now unnecessary. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Set up a connection bundle from a call, not rxrpc_conn_parametersGravatar David Howells 1-65/+67
Use the information now stored in struct rxrpc_call to configure the connection bundle and thence the connection, rather than using the rxrpc_conn_parameters struct. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Make the set of connection IDs per local endpointGravatar David Howells 1-25/+19
Make the set of connection IDs per local endpoint so that endpoints don't cause each other's connections to get dismissed. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Make the local endpoint hold a ref on a connected callGravatar David Howells 1-3/+3
Make the local endpoint and it's I/O thread hold a reference on a connected call until that call is disconnected. Without this, we're reliant on either the AF_RXRPC socket to hold a ref (which is dropped when the call is released) or a queued work item to hold a ref (the work item is being replaced with the I/O thread). Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Stash the network namespace pointer in rxrpc_localGravatar David Howells 1-1/+1
Stash the network namespace pointer in the rxrpc_local struct in addition to a pointer to the rxrpc-specific net namespace info. Use this to remove some places where the socket is passed as a parameter. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-19rxrpc: Fix security setting propagationGravatar David Howells 1-2/+0
Fix the propagation of the security settings from sendmsg to the rxrpc_call struct. Fixes: f3441d4125fc ("rxrpc: Copy client call parameters into rxrpc_call earlier") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-01rxrpc: Remove the _bh annotation from all the spinlocksGravatar David Howells 1-2/+2
None of the spinlocks in rxrpc need a _bh annotation now as the RCU callback routines no longer take spinlocks and the bulk of the packet wrangling code is now run in the I/O thread, not softirq context. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Remove RCU from peer->error_targets listGravatar David Howells 1-0/+4
Remove the RCU requirements from the peer's list of error targets so that the error distributor can call sleeping functions. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Copy client call parameters into rxrpc_call earlierGravatar David Howells 1-1/+1
Copy client call parameters into rxrpc_call earlier so that that can be used to convey them to the connection code - which can then be offloaded to the I/O thread. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Don't hold a ref for connection workqueueGravatar David Howells 1-23/+8
Currently, rxrpc gives the connection's work item a ref on the connection when it queues it - and this is called from the timer expiration function. The problem comes when queue_work() fails (ie. the work item is already queued): the timer routine must put the ref - but this may cause the cleanup code to run. This has the unfortunate effect that the cleanup code may then be run in softirq context - which means that any spinlocks it might need to touch have to be guarded to disable softirqs (ie. they need a "_bh" suffix). (1) Don't give a ref to the work item. (2) Simplify handling of service connections by adding a separate active count so that the refcount isn't also used for this. (3) Connection destruction for both client and service connections can then be cleaned up by putting rxrpc_put_connection() out of line and making a tidy progression through the destruction code (offloaded to a workqueue if put from softirq or processor function context). The RCU part of the cleanup then only deals with the freeing at the end. (4) Make rxrpc_queue_conn() return immediately if it sees the active count is -1 rather then queuing the connection. (5) Make sure that the cleanup routine waits for the work item to complete. (6) Stash the rxrpc_net pointer in the conn struct so that the rcu free routine can use it, even if the local endpoint has been freed. Unfortunately, neither the timer nor the work item can simply get around the problem by just using refcount_inc_not_zero() as the waits would still have to be done, and there would still be the possibility of having to put the ref in the expiration function. Note the connection work item is mostly going to go away with the main event work being transferred to the I/O thread, so the wait in (6) will become obsolete. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Trace rxrpc_bundle refcountGravatar David Howells 1-11/+16
Add a tracepoint for the rxrpc_bundle refcounting. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: trace: Don't use __builtin_return_address for rxrpc_call tracingGravatar David Howells 1-1/+1
In rxrpc tracing, use enums to generate lists of points of interest rather than __builtin_return_address() for the rxrpc_call tracepoint Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: trace: Don't use __builtin_return_address for rxrpc_conn tracingGravatar David Howells 1-14/+14
In rxrpc tracing, use enums to generate lists of points of interest rather than __builtin_return_address() for the rxrpc_conn tracepoint Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: trace: Don't use __builtin_return_address for rxrpc_peer tracingGravatar David Howells 1-4/+4
In rxrpc tracing, use enums to generate lists of points of interest rather than __builtin_return_address() for the rxrpc_peer tracepoint Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: trace: Don't use __builtin_return_address for rxrpc_local tracingGravatar David Howells 1-1/+1
In rxrpc tracing, use enums to generate lists of points of interest rather than __builtin_return_address() for the rxrpc_local tracepoint Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Drop rxrpc_conn_parameters from rxrpc_connection and rxrpc_bundleGravatar David Howells 1-21/+32
Remove the rxrpc_conn_parameters struct from the rxrpc_connection and rxrpc_bundle structs and emplace the members directly. These are going to get filled in from the rxrpc_call struct in future. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Remove the [_k]net() debugging macrosGravatar David Howells 1-2/+0
Remove the _net() and knet() debugging macros in favour of tracepoints. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-11-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netGravatar Jakub Kicinski 1-15/+23
tools/lib/bpf/ringbuf.c 927cbb478adf ("libbpf: Handle size overflow for ringbuf mmap") b486d19a0ab0 ("libbpf: checkpatch: Fixed code alignments in ringbuf.c") https://lore.kernel.org/all/20221121122707.44d1446a@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-18rxrpc: Fix race between conn bundle lookup and bundle removal [ZDI-CAN-15975]Gravatar David Howells 1-15/+23
After rxrpc_unbundle_conn() has removed a connection from a bundle, it checks to see if there are any conns with available channels and, if not, removes and attempts to destroy the bundle. Whilst it does check after grabbing client_bundles_lock that there are no connections attached, this races with rxrpc_look_up_bundle() retrieving the bundle, but not attaching a connection for the connection to be attached later. There is therefore a window in which the bundle can get destroyed before we manage to attach a new connection to it. Fix this by adding an "active" counter to struct rxrpc_bundle: (1) rxrpc_connect_call() obtains an active count by prepping/looking up a bundle and ditches it before returning. (2) If, during rxrpc_connect_call(), a connection is added to the bundle, this obtains an active count, which is held until the connection is discarded. (3) rxrpc_deactivate_bundle() is created to drop an active count on a bundle and destroy it when the active count reaches 0. The active count is checked inside client_bundles_lock() to prevent a race with rxrpc_look_up_bundle(). (4) rxrpc_unbundle_conn() then calls rxrpc_deactivate_bundle(). Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-15975 Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: zdi-disclosures@trendmicro.com cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-08rxrpc: Fix congestion managementGravatar David Howells 1-1/+2
rxrpc has a problem in its congestion management in that it saves the congestion window size (cwnd) from one call to another, but if this is 0 at the time is saved, then the next call may not actually manage to ever transmit anything. To this end: (1) Don't save cwnd between calls, but rather reset back down to the initial cwnd and re-enter slow-start if data transmission is idle for more than an RTT. (2) Preserve ssthresh instead, as that is a handy estimate of pipe capacity. Knowing roughly when to stop slow start and enter congestion avoidance can reduce the tendency to overshoot and drop larger amounts of packets when probing. In future, cwind growth also needs to be constrained when the window isn't being filled due to being application limited. Reported-by: Simon Wilkinson <sxw@auristor.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-05-22rxrpc: Use refcount_t rather than atomic_tGravatar David Howells 1-14/+16
Move to using refcount_t rather than atomic_t for refcounts in rxrpc. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-29rxrpc: Fix rxrpc_peer leak in rxrpc_look_up_bundle()Gravatar Eiichi Tsukata 1-5/+9
Need to call rxrpc_put_peer() for bundle candidate before kfree() as it holds a ref to rxrpc_peer. [DH: v2: Changed to abstract out the bundle freeing code into a function] Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/20211121041608.133740-1-eiichi.tsukata@nutanix.com/ # v1
2020-11-23rxrpc: Merge prime_packet_security into init_connection_securityGravatar David Howells 1-6/+0
Merge the ->prime_packet_security() into the ->init_connection_security() hook as they're always called together. Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-15rxrpc: Fix loss of final ack on shutdownGravatar David Howells 1-0/+3
Fix the loss of transmission of a call's final ack when a socket gets shut down. This means that the server will retransmit the last data packet or send a ping ack and then get an ICMP indicating the port got closed. The server will then view this as a failure. Fixes: 3136ef49a14c ("rxrpc: Delay terminal ACK transmission on a client call") Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-15rxrpc: Fix bundle counting for exclusive connectionsGravatar David Howells 1-2/+3
Fix rxrpc_unbundle_conn() to not drop the bundle usage count when cleaning up an exclusive connection. Based on the suggested fix from Hillf Danton. Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Reported-by: syzbot+d57aaf84dd8a550e6d91@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Hillf Danton <hdanton@sina.com>
2020-09-14rxrpc: Fix an overget of the conn bundle when setting up a client connGravatar David Howells 1-1/+0
When setting up a client connection, a second ref is accidentally obtained on the connection bundle (we get one when allocating the conn and a second one when adding the conn to the bundle). Fix it to only use the ref obtained by rxrpc_alloc_client_connection() and not to add a second when adding the candidate conn to the bundle. Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-14rxrpc: Fix conn bundle leak in net-namespace exitGravatar David Howells 1-0/+1
When the network namespace exits, rxrpc_clean_up_local_conns() needs to unbundle each client connection it evicts. Fix it to do this. kernel BUG at net/rxrpc/conn_object.c:481! RIP: 0010:rxrpc_destroy_all_connections.cold+0x11/0x13 net/rxrpc/conn_object.c:481 Call Trace: rxrpc_exit_net+0x1a4/0x2e0 net/rxrpc/net_ns.c:119 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:186 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Reported-by: syzbot+52071f826a617b9c76ed@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-14rxrpc: Fix an error goto in rxrpc_connect_call()Gravatar David Howells 1-2/+3
Fix an error-handling goto in rxrpc_connect_call() whereby it will jump to free the bundle it failed to allocate. Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-08rxrpc: Allow multiple client connections to the same peerGravatar David Howells 1-0/+6
Allow the number of parallel connections to a machine to be expanded from a single connection to a maximum of four. This allows up to 16 calls to be in progress at the same time to any particular peer instead of 4. Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-08rxrpc: Rewrite the client connection managerGravatar David Howells 1-594/+487
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 <dhowells@redhat.com>
2020-08-23treewide: Use fallthrough pseudo-keywordGravatar Gustavo A. R. Silva 1-1/+1
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 <gustavoars@kernel.org>
2020-03-13rxrpc: Fix call interruptibility handlingGravatar David Howells 1-3/+10
Fix the interruptibility of kernel-initiated client calls so that they're either only interruptible when they're waiting for a call slot to come available or they're not interruptible at all. Either way, they're not interruptible during transmission. This should help prevent StoreData calls from being interrupted when writeback is in progress. It doesn't, however, handle interruption during the receive phase. Userspace-initiated calls are still interruptable. After the signal has been handled, sendmsg() will return the amount of data copied out of the buffer and userspace can perform another sendmsg() call to continue transmission. Fixes: bc5e3a546d55 ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals") Signed-off-by: David Howells <dhowells@redhat.com>
2020-02-03rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnectGravatar David Howells 1-2/+1
When a call is disconnected, the connection pointer from the call is cleared to make sure it isn't used again and to prevent further attempted transmission for the call. Unfortunately, there might be a daemon trying to use it at the same time to transmit a packet. Fix this by keeping call->conn set, but setting a flag on the call to indicate disconnection instead. Remove also the bits in the transmission functions where the conn pointer is checked and a ref taken under spinlock as this is now redundant. Fixes: 8d94aa381dab ("rxrpc: Calls shouldn't hold socket refs") Signed-off-by: David Howells <dhowells@redhat.com>
2019-10-07rxrpc: Fix call crypto state cleanupGravatar David Howells 1-0/+3
Fix the cleanup of the crypto state on a call after the call has been disconnected. As the call has been disconnected, its connection ref has been discarded and so we can't go through that to get to the security ops table. Fix this by caching the security ops pointer in the rxrpc_call struct and using that when freeing the call security state. Also use this in other places we're dealing with call-specific security. The symptoms look like: BUG: KASAN: use-after-free in rxrpc_release_call+0xb2d/0xb60 net/rxrpc/call_object.c:481 Read of size 8 at addr ffff888062ffeb50 by task syz-executor.5/4764 Fixes: 1db88c534371 ("rxrpc: Fix -Wframe-larger-than= warnings from on-stack crypto") Reported-by: syzbot+eed305768ece6682bb7f@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com>
2019-10-07rxrpc: Fix trace-after-put looking at the put connection recordGravatar David Howells 1-2/+4
rxrpc_put_*conn() calls trace_rxrpc_conn() after they have done the decrement of the refcount - which looks at the debug_id in the connection record. But unless the refcount was reduced to zero, we no longer have the right to look in the record and, indeed, it may be deleted by some other thread. Fix this by getting the debug_id out before decrementing the refcount and then passing that into the tracepoint. Fixes: 363deeab6d0f ("rxrpc: Add connection tracepoint and client conn state tracepoint") Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-30rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up [ver #2]Gravatar David Howells 1-0/+44
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 <dhowells@redhat.com> Tested-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36Gravatar Thomas Gleixner 1-6/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public licence as published by the free software foundation either version 2 of the licence or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 114 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16rxrpc: Allow the kernel to mark a call as being non-interruptibleGravatar David Howells 1-2/+6
Allow kernel services using AF_RXRPC to indicate that a call should be non-interruptible. This allows kafs to make things like lock-extension and writeback data storage calls non-interruptible. If this is set, signals will be ignored for operations on that call where possible - such as waiting to get a call channel on an rxrpc connection. It doesn't prevent UDP sendmsg from being interrupted, but that will be handled by packet retransmission. rxrpc_kernel_recv_data() isn't affected by this since that never waits, preferring instead to return -EAGAIN and leave the waiting to the caller. Userspace initiated calls can't be set to be uninterruptible at this time. Signed-off-by: David Howells <dhowells@redhat.com>
2019-03-08rxrpc: Fix client call queueing, waiting for channelGravatar David Howells 1-2/+2
rxrpc_get_client_conn() adds a new call to the front of the waiting_calls queue if the connection it's going to use already exists. This is bad as it allows calls to get starved out. Fix this by adding to the tail instead. Also change the other enqueue point in the same function to put it on the front (ie. when we have a new connection). This makes the point that in the case of a new connection the new call goes at the front (though it doesn't actually matter since the queue should be unoccupied). Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-08rxrpc: Fix client call connect/disconnect raceGravatar David Howells 1-5/+15
rxrpc_disconnect_client_call() reads the call's connection ID protocol value (call->cid) as part of that function's variable declarations. This is bad because it's not inside the locked section and so may race with someone granting use of the channel to the call. This manifests as an assertion failure (see below) where the call in the presumed channel (0 because call->cid wasn't set when we read it) doesn't match the call attached to the channel we were actually granted (if 1, 2 or 3). Fix this by moving the read and dependent calculations inside of the channel_lock section. Also, only set the channel number and pointer variables if cid is not zero (ie. unset). This problem can be induced by injecting an occasional error in rxrpc_wait_for_channel() before the call to schedule(). Make two further changes also: (1) Add a trace for wait failure in rxrpc_connect_call(). (2) Drop channel_lock before BUG'ing in the case of the assertion failure. The failure causes a trace akin to the following: rxrpc: Assertion failed - 18446612685268945920(0xffff8880beab8c00) == 18446612685268621312(0xffff8880bea69800) is false ------------[ cut here ]------------ kernel BUG at net/rxrpc/conn_client.c:824! ... RIP: 0010:rxrpc_disconnect_client_call+0x2bf/0x99d ... Call Trace: rxrpc_connect_call+0x902/0x9b3 ? wake_up_q+0x54/0x54 rxrpc_new_client_call+0x3a0/0x751 ? rxrpc_kernel_begin_call+0x141/0x1bc ? afs_alloc_call+0x1b5/0x1b5 rxrpc_kernel_begin_call+0x141/0x1bc afs_make_call+0x20c/0x525 ? afs_alloc_call+0x1b5/0x1b5 ? __lock_is_held+0x40/0x71 ? lockdep_init_map+0xaf/0x193 ? lockdep_init_map+0xaf/0x193 ? __lock_is_held+0x40/0x71 ? yfs_fs_fetch_data+0x33b/0x34a yfs_fs_fetch_data+0x33b/0x34a afs_fetch_data+0xdc/0x3b7 afs_read_dir+0x52d/0x97f afs_dir_iterate+0xa0/0x661 ? iterate_dir+0x63/0x141 iterate_dir+0xa2/0x141 ksys_getdents64+0x9f/0x11b ? filldir+0x111/0x111 ? do_syscall_64+0x3e/0x1a0 __x64_sys_getdents64+0x16/0x19 do_syscall_64+0x7d/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-15Revert "rxrpc: Allow failed client calls to be retried"Gravatar David Howells 1-4/+1
The changes introduced to allow rxrpc calls to be retried creates an issue when it comes to refcounting afs_call structs. The problem is that when rxrpc_send_data() queues the last packet for an asynchronous call, the following sequence can occur: (1) The notify_end_tx callback is invoked which causes the state in the afs_call to be changed from AFS_CALL_CL_REQUESTING or AFS_CALL_SV_REPLYING. (2) afs_deliver_to_call() can then process event notifications from rxrpc on the async_work queue. (3) Delivery of events, such as an abort from the server, can cause the afs_call state to be changed to AFS_CALL_COMPLETE on async_work. (4) For an asynchronous call, afs_process_async_call() notes that the call is complete and tried to clean up all the refs on async_work. (5) rxrpc_send_data() might return the amount of data transferred (success) or an error - which could in turn reflect a local error or a received error. Synchronising the clean up after rxrpc_kernel_send_data() returns an error with the asynchronous cleanup is then tricky to get right. Mostly revert commit c038a58ccfd6704d4d7d60ed3d6a0fca13cf13a4. The two API functions the original commit added aren't currently used. This makes rxrpc_kernel_send_data() always return successfully if it queued the data it was given. Note that this doesn't affect synchronous calls since their Rx notification function merely pokes a wait queue and does not refcounting. The asynchronous call notification function *has* to do refcounting and pass a ref over the work item to avoid the need to sync the workqueue in call cleanup. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05rxrpc: Fix some missed refs to init_netGravatar David Howells 1-4/+6
Fix some refs to init_net that should've been changed to the appropriate network namespace. Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing") Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Paolo Abeni <pabeni@redhat.com>
2018-09-28rxrpc: Fix error distributionGravatar David Howells 1-2/+2
Fix error distribution by immediately delivering the errors to all the affected calls rather than deferring them to a worker thread. The problem with the latter is that retries and things can happen in the meantime when we want to stop that sooner. To this end: (1) Stop the error distributor from removing calls from the error_targets list so that peer->lock isn't needed to synchronise against other adds and removals. (2) Require the peer's error_targets list to be accessed with RCU, thereby avoiding the need to take peer->lock over distribution. (3) Don't attempt to affect a call's state if it is already marked complete. Signed-off-by: David Howells <dhowells@redhat.com>
2018-08-01rxrpc: Trace packet transmissionGravatar David Howells 1-0/+1
Trace successful packet transmission (kernel_sendmsg() succeeded, that is) in AF_RXRPC. We can share the enum that defines the transmission points with the trace_rxrpc_tx_fail() tracepoint, so rename its constants to be applicable to both. Also, save the internal call->debug_id in the rxrpc_channel struct so that it can be used in retransmission trace lines. Signed-off-by: David Howells <dhowells@redhat.com>
2018-08-01rxrpc: remove redundant variables 'sp' and 'did_discard'Gravatar YueHaibing 1-2/+0
Variables 'sp' and 'did_discard' are being assigned, but are never used, hence they are redundant and can be removed. fix following warning: net/rxrpc/call_event.c:165:25: warning: variable 'sp' set but not used [-Wunused-but-set-variable] net/rxrpc/conn_client.c:1054:7: warning: variable 'did_discard' set but not used [-Wunused-but-set-variable] Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David Howells <dhowells@redhat.com>
2018-03-30rxrpc: Fix apparent leak of rxrpc_local objectsGravatar David Howells 1-0/+1
rxrpc_local objects cannot be disposed of until all the connections that point to them have been RCU'd as a connection object holds refcount on the local endpoint it is communicating through. Currently, this can cause an assertion failure to occur when a network namespace is destroyed as there's no check that the RCU destructors for the connections have been run before we start trying to destroy local endpoints. The kernel reports: rxrpc: AF_RXRPC: Leaked local 0000000036a41bc1 {5} ------------[ cut here ]------------ kernel BUG at ../net/rxrpc/local_object.c:439! Fix this by keeping a count of the live connections and waiting for it to go to zero at the end of rxrpc_destroy_all_connections(). Fixes: dee46364ce6f ("rxrpc: Add RCU destruction for connections and calls") Signed-off-by: David Howells <dhowells@redhat.com>
2018-03-30rxrpc: Fix checker warnings and errorsGravatar David Howells 1-1/+1
Fix various issues detected by checker. Errors: (*) rxrpc_discard_prealloc() should be using rcu_assign_pointer to set call->socket. Warnings: (*) rxrpc_service_connection_reaper() should be passing NULL rather than 0 to trace_rxrpc_conn() as the where argument. (*) rxrpc_disconnect_client_call() should get its net pointer via the call->conn rather than call->sock to avoid a warning about accessing an RCU pointer without protection. (*) Proc seq start/stop functions need annotation as they pass locks between the functions. False positives: (*) Checker doesn't correctly handle of seq-retry lock context balance in rxrpc_find_service_conn_rcu(). (*) Checker thinks execution may proceed past the BUG() in rxrpc_publish_service_conn(). (*) Variable length array warnings from SKCIPHER_REQUEST_ON_STACK() in rxkad.c. Signed-off-by: David Howells <dhowells@redhat.com>
2018-02-07rxrpc: Fix received abort handlingGravatar David Howells 1-1/+2
AF_RXRPC is incorrectly sending back to the server any abort it receives for a client connection. This is due to the final-ACK offload to the connection event processor patch. The abort code is copied into the last-call information on the connection channel and then the event processor is set. Instead, the following should be done: (1) In the case of a final-ACK for a successful call, the ACK should be scheduled as before. (2) In the case of a locally generated ABORT, the ABORT details should be cached for sending in response to further packets related to that call and no further action scheduled at call disconnect time. (3) In the case of an ACK received from the peer, the call should be considered dead, no ABORT should be transmitted at this time. In response to further non-ABORT packets from the peer relating to this call, an RX_USER_ABORT ABORT should be transmitted. (4) In the case of a call killed due to network error, an RX_USER_ABORT ABORT should be cached for transmission in response to further packets, but no ABORT should be sent at this time. Fixes: 3136ef49a14c ("rxrpc: Delay terminal ACK transmission on a client call") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>