Commit graph

94 commits

Author SHA1 Message Date
Thomas Gleixner
8fa7292fee treewide: Switch/rename to timer_delete[_sync]()
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-05 10:30:12 +02:00
David Howells
a2ea9a9072 rxrpc: Use irq-disabling spinlocks between app and I/O thread
Where a spinlock is used by both the application thread and the I/O thread,
use irq-disabling locking so that an interrupt taken on the app thread
doesn't also slow down 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
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 13:48:31 -08:00
David Howells
f7dd0dc965 rxrpc: Adjust names and types of congestion-related fields
Adjust some of the names of fields and constants to make them look a bit
more like the TCP congestion symbol names, such as flight_size -> in_flight
and congest_mode to ca_state.

Move the persistent congestion-related fields from the rxrpc_ack_summary
struct into the rxrpc_call struct rather than copying them out and back in
again.  The rxrpc_congest tracepoint can fetch them from the call struct.

Rename the counters for soft acks and nacks to have an 's' on the front to
reflect the softness, e.g. nr_acks -> nr_sacks.

Make fields counting numbers of packets or numbers of acks u16 rather than
u8 to allow for windows of up to 8192 DATA packets in flight in future.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-23-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 13:48:28 -08:00
David Howells
9e3cccd176 rxrpc: Fix CPU time starvation in I/O thread
Starvation can happen in the rxrpc I/O thread because it goes back to the
top of the I/O loop after it does any one thing without trying to give any
other connection or call CPU time.  Also, because it processes one call
packet at a time, it tries to do the retransmission loop after each ACK
without checking to see if there are other ACKs already in the queue that
can update the SACK state.

Fix this by:

 (1) Add a received-packet queue on each call.

 (2) Distribute packets from the master Rx queue to the individual call,
     conn and error queues and 'poking' calls to add them to the attend
     queue first thing in the I/O thread.

 (3) Go through all the attention-seeking connections and calls before
     going back to the top of the I/O thread.  Each queue is extracted as a
     whole and then gone through so that new additions to insert themselves
     into the queue.

 (4) Make the call event handler go through all the packets currently on
     the call's rx_queue before transmitting and retransmitting DATA
     packets.

 (5) Drop the skb argument from the call event handler as this is now
     replaced with the rx_queue.  Instead, keep track of whether we
     received a packet or an ACK for the tests that used to rely on that.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-14-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 13:48:26 -08:00
David Howells
29e03ec757 rxrpc: Use umin() and umax() rather than min_t()/max_t() where possible
Use umin() and umax() rather than min_t()/max_t() where the type specified
is an unsigned type.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-4-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 13:48:23 -08:00
David Howells
fc9de52de3 rxrpc: Fix missing locking causing hanging calls
If a call gets aborted (e.g. because kafs saw a signal) between it being
queued for connection and the I/O thread picking up the call, the abort
will be prioritised over the connection and it will be removed from
local->new_client_calls by rxrpc_disconnect_client_call() without a lock
being held.  This may cause other calls on the list to disappear if a race
occurs.

Fix this by taking the client_call_lock when removing a call from whatever
list its ->wait_link happens to be on.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-afs@lists.infradead.org
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Fixes: 9d35d880e0 ("rxrpc: Move client call connection to the I/O thread")
Link: https://patch.msgid.link/726660.1730898202@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-07 11:30:34 -08:00
David Howells
d73f3a7488 rxrpc: Strip barriers and atomics off of timer tracking
Strip the atomic ops and barriering off of the call timer tracking as this
is handled solely within the I/O thread, except for expect_term_by which is
set by sendmsg().

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
2024-02-29 15:49:57 +00:00
David Howells
d2ce4a84c2 rxrpc: Create a procfile to display outstanding client conn bundles
Create /proc/net/rxrpc/bundles to display outstanding rxrpc client
connection bundles.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
2023-12-24 15:22:56 +00:00
David Howells
0c3bd086d1 rxrpc: Fix some minor issues with bundle tracing
Fix some superficial issues with the tracing of rxrpc_bundle structs,
including:

 (1) Set the debug_id when the bundle is allocated rather than when it is
     set up so that the "NEW" trace line displays the correct bundle ID.

 (2) Show the refcount when emitting the "FREE" traceline.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-17 00:18:15 +00:00
David Howells
9d35d880e0 rxrpc: Move client call connection to the I/O thread
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: cf37b59875 ("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
2023-01-06 09:43:33 +00:00
David Howells
0d6bf319bc rxrpc: Move the client conn cache management to the I/O thread
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
2023-01-06 09:43:33 +00:00
David Howells
96b4059f43 rxrpc: Remove call->state_lock
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
2023-01-06 09:43:33 +00:00
David Howells
1bab27af6b rxrpc: Set up a connection bundle from a call, not rxrpc_conn_parameters
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
2023-01-06 09:43:32 +00:00
David Howells
f06cb29189 rxrpc: Make the set of connection IDs per local endpoint
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
2023-01-06 09:43:32 +00:00
David Howells
5040011d07 rxrpc: Make the local endpoint hold a ref on a connected call
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
2023-01-06 09:43:31 +00:00
David Howells
8a758d98db rxrpc: Stash the network namespace pointer in rxrpc_local
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
2023-01-06 09:43:31 +00:00
David Howells
fdb99487b0 rxrpc: Fix security setting propagation
Fix the propagation of the security settings from sendmsg to the rxrpc_call
struct.

Fixes: f3441d4125 ("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>
2022-12-19 09:51:31 +00:00
David Howells
3dd9c8b5f0 rxrpc: Remove the _bh annotation from all the spinlocks
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
2022-12-01 13:36:42 +00:00
David Howells
29fb4ec385 rxrpc: Remove RCU from peer->error_targets list
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
2022-12-01 13:36:41 +00:00
David Howells
f3441d4125 rxrpc: Copy client call parameters into rxrpc_call earlier
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
2022-12-01 13:36:41 +00:00
David Howells
3cec055c56 rxrpc: Don't hold a ref for connection workqueue
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
2022-12-01 13:36:40 +00:00
David Howells
fa3492abb6 rxrpc: Trace rxrpc_bundle refcount
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
2022-12-01 13:36:39 +00:00
David Howells
cb0fc0c972 rxrpc: trace: Don't use __builtin_return_address for rxrpc_call tracing
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
2022-12-01 13:36:39 +00:00
David Howells
7fa25105b2 rxrpc: trace: Don't use __builtin_return_address for rxrpc_conn tracing
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
2022-12-01 13:36:39 +00:00
David Howells
47c810a798 rxrpc: trace: Don't use __builtin_return_address for rxrpc_peer tracing
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
2022-12-01 13:36:38 +00:00
David Howells
0fde882fc9 rxrpc: trace: Don't use __builtin_return_address for rxrpc_local tracing
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
2022-12-01 13:36:38 +00:00
David Howells
2cc800863c rxrpc: Drop rxrpc_conn_parameters from rxrpc_connection and rxrpc_bundle
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
2022-12-01 13:36:38 +00:00
David Howells
e969c92ce5 rxrpc: Remove the [_k]net() debugging macros
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
2022-12-01 13:36:38 +00:00
Jakub Kicinski
f2bb566f5c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/lib/bpf/ringbuf.c
  927cbb478a ("libbpf: Handle size overflow for ringbuf mmap")
  b486d19a0a ("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>
2022-11-29 13:04:52 -08:00
David Howells
3bcd6c7eaa rxrpc: Fix race between conn bundle lookup and bundle removal [ZDI-CAN-15975]
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: 245500d853 ("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>
2022-11-18 12:05:44 +00:00
David Howells
1fc4fa2ac9 rxrpc: Fix congestion management
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
2022-11-08 16:42:28 +00:00
David Howells
a05754295e rxrpc: Use refcount_t rather than atomic_t
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>
2022-05-22 21:03:01 +01:00
Eiichi Tsukata
ca77fba821 rxrpc: Fix rxrpc_peer leak in rxrpc_look_up_bundle()
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: 245500d853 ("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
2021-11-29 15:39:40 +00:00
David Howells
8d47a43c48 rxrpc: Merge prime_packet_security into init_connection_security
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>
2020-11-23 18:09:30 +00:00
David Howells
ddc7834af8 rxrpc: Fix loss of final ack on shutdown
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: 3136ef49a1 ("rxrpc: Delay terminal ACK transmission on a client call")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-15 13:28:00 +01:00
David Howells
f3af4ad1e0 rxrpc: Fix bundle counting for exclusive connections
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: 245500d853 ("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>
2020-10-15 13:28:00 +01:00
David Howells
f1b4497487 rxrpc: Fix an overget of the conn bundle when setting up a client conn
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: 245500d853 ("rxrpc: Rewrite the client connection manager")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-14 16:18:59 +01:00
David Howells
546a42410b rxrpc: Fix conn bundle leak in net-namespace exit
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: 245500d853 ("rxrpc: Rewrite the client connection manager")
Reported-by: syzbot+52071f826a617b9c76ed@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-14 16:18:59 +01:00
David Howells
456b2f2dc7 rxrpc: Fix an error goto in rxrpc_connect_call()
Fix an error-handling goto in rxrpc_connect_call() whereby it will jump to
free the bundle it failed to allocate.

Fixes: 245500d853 ("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>
2020-09-14 12:58:17 +01:00
David Howells
288827d53e rxrpc: Allow multiple client connections to the same peer
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>
2020-09-08 21:11:47 +01:00
David Howells
245500d853 rxrpc: Rewrite the client connection manager
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>
2020-09-08 21:11:43 +01:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
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>
2020-08-23 17:36:59 -05:00
David Howells
e138aa7d32 rxrpc: Fix call interruptibility handling
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: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:30 +00:00
David Howells
5273a191dc rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect
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: 8d94aa381d ("rxrpc: Calls shouldn't hold socket refs")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-02-03 10:25:30 +00:00
David Howells
91fcfbe885 rxrpc: Fix call crypto state cleanup
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: 1db88c5343 ("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>
2019-10-07 11:05:05 +01:00
David Howells
4c1295dccc rxrpc: Fix trace-after-put looking at the put connection record
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: 363deeab6d ("rxrpc: Add connection tracepoint and client conn state tracepoint")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-10-07 11:05:05 +01:00
David Howells
d12040b693 rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up [ver #2]
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: 3d18cbb7fd ("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>
2019-08-30 15:06:52 -07:00
Thomas Gleixner
b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
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>
2019-05-24 17:27:11 +02:00
David Howells
b960a34b73 rxrpc: Allow the kernel to mark a call as being non-interruptible
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>
2019-05-16 16:25:20 +01:00
David Howells
69ffaebb90 rxrpc: Fix client call queueing, waiting for channel
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: 45025bceef ("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>
2019-03-08 18:24:53 -08:00