Fix the handling of sendmsg() with MSG_WAITALL for userspace to round the
timeout for when a signal occurs up to at least two jiffies as a 1 jiffy
timeout may end up being effectively 0 if jiffies wraps at the wrong time.
Fixes: bc5e3a546d55 ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
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>
Abstract out the calculation of there being sufficient Tx buffer space. This is reproduced several times in the rxrpc sendmsg code. Signed-off-by: David Howells <dhowells@redhat.com>
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>
When sendmsg() finds a call to continue on with, if the call is in an
inappropriate state, it doesn't release the ref it just got on that call
before returning an error.
This causes the following symptom to show up with kasan:
BUG: KASAN: use-after-free in rxrpc_send_keepalive+0x8a2/0x940
net/rxrpc/output.c:635
Read of size 8 at addr ffff888064219698 by task kworker/0:3/11077
where line 635 is:
whdr.epoch = htonl(peer->local->rxnet->epoch);
The local endpoint (which cannot be pinned by the call) has been released,
but not the peer (which is pinned by the call).
Fix this by releasing the call in the error path.
Fixes: 37411cad633f ("rxrpc: Fix potential NULL-pointer exception")
Reported-by: syzbot+d850c266e3df14da1d31@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Use the previously-added transmit-phase skbuff private flag to simplify the socket buffer tracing a bit. Which phase the skbuff comes from can now be divined from the skb rather than having to be guessed from the call state. We can also reduce the number of rxrpc_skb_trace values by eliminating the difference between Tx and Rx in the symbols. Signed-off-by: David Howells <dhowells@redhat.com>
Add a flag in the private data on an skbuff to indicate that this is a
transmission-phase buffer rather than a receive-phase buffer.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the fact that a notification isn't sent to the recvmsg side to indicate
a call failed when sendmsg() fails to transmit a DATA packet with the error
ENETUNREACH, EHOSTUNREACH or ECONNREFUSED.
Without this notification, the afs client just sits there waiting for the
call to complete in some manner (which it's not now going to do), which
also pins the rxrpc call in place.
This can be seen if the client has a scope-level IPv6 address, but not a
global-level IPv6 address, and we try and transmit an operation to a
server's IPv6 address.
Looking in /proc/net/rxrpc/calls shows completed calls just sat there with
an abort code of RX_USER_ABORT and an error code of -ENETUNREACH.
Fixes: c54e43d752c7 ("rxrpc: Fix missing start of call timeout")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
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>
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>