AF_RXRPC has a keepalive message generator that generates a message for a
peer ~20s after the last transmission to that peer to keep firewall ports
open. The implementation is incorrect in the following ways:
(1) It mixes up ktime_t and time64_t types.
(2) It uses ktime_get_real(), the output of which may jump forward or
backward due to adjustments to the time of day.
(3) If the current time jumps forward too much or jumps backwards, the
generator function will crank the base of the time ring round one slot
at a time (ie. a 1s period) until it catches up, spewing out VERSION
packets as it goes.
Fix the problem by:
(1) Only using time64_t. There's no need for sub-second resolution.
(2) Use ktime_get_seconds() rather than ktime_get_real() so that time
isn't perceived to go backwards.
(3) Simplifying rxrpc_peer_keepalive_worker() by splitting it into two
parts:
(a) The "worker" function that manages the buckets and the timer.
(b) The "dispatch" function that takes the pending peers and
potentially transmits a keepalive packet before putting them back
in the ring into the slot appropriate to the revised last-Tx time.
(4) Taking everything that's pending out of the ring and splicing it into
a temporary collector list for processing.
In the case that there's been a significant jump forward, the ring
gets entirely emptied and then the time base can be warped forward
before the peers are processed.
The warping can't happen if the ring isn't empty because the slot a
peer is in is keepalive-time dependent, relative to the base time.
(5) Limit the number of iterations of the bucket array when scanning it.
(6) Set the timer to skip any empty slots as there's no point waking up if
there's nothing to do yet.
This can be triggered by an incoming call from a server after a reboot with
AF_RXRPC and AFS built into the kernel causing a peer record to be set up
before userspace is started. The system clock is then adjusted by
userspace, thereby potentially causing the keepalive generator to have a
meltdown - which leads to a message like:
watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [kworker/0:1:23]
...
Workqueue: krxrpcd rxrpc_peer_keepalive_worker
EIP: lock_acquire+0x69/0x80
...
Call Trace:
? rxrpc_peer_keepalive_worker+0x5e/0x350
? _raw_spin_lock_bh+0x29/0x60
? rxrpc_peer_keepalive_worker+0x5e/0x350
? rxrpc_peer_keepalive_worker+0x5e/0x350
? __lock_acquire+0x3d3/0x870
? process_one_work+0x110/0x340
? process_one_work+0x166/0x340
? process_one_work+0x110/0x340
? worker_thread+0x39/0x3c0
? kthread+0xdb/0x110
? cancel_delayed_work+0x90/0x90
? kthread_stop+0x70/0x70
? ret_from_fork+0x19/0x24
Fixes: ace45bec6d ("rxrpc: Fix firewall route keepalive")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release. All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
When a new client call is requested, an rxrpc_conn_parameters struct object
is passed in with a bunch of parameters set, such as the local endpoint to
use. A pointer to the target peer record is also placed in there by
rxrpc_get_client_conn() - and this is removed if and only if a new
connection object is allocated. Thus it leaks if a new connection object
isn't allocated.
Fix this by putting any peer object attached to the rxrpc_conn_parameters
object in the function that allocated it.
Fixes: 19ffa01c9c ("rxrpc: Use structs to hold connection params and protocol info")
Signed-off-by: David Howells <dhowells@redhat.com>
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: dee46364ce ("rxrpc: Add RCU destruction for connections and calls")
Signed-off-by: David Howells <dhowells@redhat.com>
rxrpc_call structs don't pin sockets or network namespaces, but may attempt
to access both after their refcount reaches 0 so that they can detach
themselves from the network namespace. However, there's no guarantee that
the socket still exists at this point (so sock_net(&call->socket->sk) may
be invalid) and the namespace may have gone away if the call isn't pinning
a peer.
Fix this by (a) carrying a net pointer in the rxrpc_call struct and (b)
waiting for all calls to be destroyed when the network namespace goes away.
This was detected by checker:
net/rxrpc/call_object.c:634:57: warning: incorrect type in argument 1 (different address spaces)
net/rxrpc/call_object.c:634:57: expected struct sock const *sk
net/rxrpc/call_object.c:634:57: got struct sock [noderef] <asn:4>*<noident>
Fixes: 2baec2c3f8 ("rxrpc: Support network namespacing")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the firewall route keepalive part of AF_RXRPC which is currently
function incorrectly by replying to VERSION REPLY packets from the server
with VERSION REQUEST packets.
Instead, send VERSION REPLY packets to the peers of service connections to
act as keep-alives 20s after the latest packet was transmitted to that
peer.
Also, just discard VERSION REPLY packets rather than replying to them.
Signed-off-by: David Howells <dhowells@redhat.com>
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These pernet_operations modifies rxrpc_net_id-pointed
per-net entities. There is external link to AF_RXRPC
in fs/afs/Kconfig, but it seems there is no other
pernet_operations interested in that per-net entities.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the rxrpc connection expiry timers so that connections for closed
AF_RXRPC sockets get deleted in a more timely fashion, freeing up the
transport UDP port much more quickly.
(1) Replace the delayed work items with work items plus timers so that
timer_reduce() can be used to shorten them and so that the timer
doesn't requeue the work item if the net namespace is dead.
(2) Don't use queue_delayed_work() as that won't alter the timeout if the
timer is already running.
(3) Don't rearm the timers if the network namespace is dead.
Signed-off-by: David Howells <dhowells@redhat.com>
RxRPC service endpoints expire like they're supposed to by the following
means:
(1) Mark dead rxrpc_net structs (with ->live) rather than twiddling the
global service conn timeout, otherwise the first rxrpc_net struct to
die will cause connections on all others to expire immediately from
then on.
(2) Mark local service endpoints for which the socket has been closed
(->service_closed) so that the expiration timeout can be much
shortened for service and client connections going through that
endpoint.
(3) rxrpc_put_service_conn() needs to schedule the reaper when the usage
count reaches 1, not 0, as idle conns have a 1 count.
(4) The accumulator for the earliest time we might want to schedule for
should be initialised to jiffies + MAX_JIFFY_OFFSET, not ULONG_MAX as
the comparison functions use signed arithmetic.
(5) Simplify the expiration handling, adding the expiration value to the
idle timestamp each time rather than keeping track of the time in the
past before which the idle timestamp must go to be expired. This is
much easier to read.
(6) Ignore the timeouts if the net namespace is dead.
(7) Restart the service reaper work item rather the client reaper.
Signed-off-by: David Howells <dhowells@redhat.com>
The proc_remove call is dead code as it occurs after a return and
hence can never be called. Remove it.
Detected by CoverityScan, CID#1437743 ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Support network namespacing in AF_RXRPC with the following changes:
(1) All the local endpoint, peer and call lists, locks, counters, etc. are
moved into the per-namespace record.
(2) All the connection tracking is moved into the per-namespace record
with the exception of the client connection ID tree, which is kept
global so that connection IDs are kept unique per-machine.
(3) Each namespace gets its own epoch. This allows each network namespace
to pretend to be a separate client machine.
(4) The /proc/net/rxrpc_xxx files are now called /proc/net/rxrpc/xxx and
the contents reflect the namespace.
fs/afs/ should be okay with this patch as it explicitly requires the current
net namespace to be init_net to permit a mount to proceed at the moment. It
will, however, need updating so that cells, IP addresses and DNS records are
per-namespace also.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David Howells