linux-stable.git/net/rxrpc, branch v5.4.232

rxrpc: Fix missing unlock in rxrpc_do_sendmsg()

2023-01-18T10:41:33+00:00

[ Upstream commit 4feb2c44629e6f9b459b41a5a60491069d346a95 ]

One of the error paths in rxrpc_do_sendmsg() doesn't unlock the call mutex
before returning.  Fix it to do this.

Note that this still doesn't get rid of the checker warning:

   ../net/rxrpc/sendmsg.c:617:5: warning: context imbalance in 'rxrpc_do_sendmsg' - wrong count at exit

I think the interplay between the socket lock and the call's user_mutex may
be too complicated for checker to analyse, especially as
rxrpc_new_client_call_for_sendmsg(), which it calls, returns with the
call's user_mutex if successful but unconditionally drops the socket lock.

Fixes: e754eba685aa ("rxrpc: Provide a cmsg to specify the amount of Tx data for a call")
Signed-off-by: David Howells 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rxrpc: Fix ack.bufferSize to be 0 when generating an ack

2023-01-18T10:41:02+00:00

[ Upstream commit 8889a711f9b4dcf4dd1330fa493081beebd118c9 ]

ack.bufferSize should be set to 0 when generating an ack.

Fixes: 8d94aa381dab ("rxrpc: Calls shouldn't hold socket refs")
Reported-by: Jeffrey Altman 
Signed-off-by: David Howells 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Signed-off-by: Sasha Levin

rxrpc: Fix calc of resend age

2022-09-28T09:03:58+00:00

[ Upstream commit 214a9dc7d852216e83acac7b75bc18f01ce184c2 ]

Fix the calculation of the resend age to add a microsecond value as
microseconds, not nanoseconds.

Signed-off-by: David Howells 
Signed-off-by: Sasha Levin

rxrpc: Fix local destruction being repeated

2022-09-28T09:03:58+00:00

[ Upstream commit d3d863036d688313f8d566b87acd7d99daf82749 ]

If the local processor work item for the rxrpc local endpoint gets requeued
by an event (such as an incoming packet) between it getting scheduled for
destruction and the UDP socket being closed, the rxrpc_local_destroyer()
function can get run twice.  The second time it can hang because it can end
up waiting for cleanup events that will never happen.

Signed-off-by: David Howells 
Signed-off-by: Sasha Levin

rxrpc: Fix an insufficiently large sglist in rxkad_verify_packet_2()

2022-09-15T10:04:55+00:00

[ Upstream commit 0d40f728e28393a8817d1fcae923dfa3409e488c ]

rxkad_verify_packet_2() has a small stack-allocated sglist of 4 elements,
but if that isn't sufficient for the number of fragments in the socket
buffer, we try to allocate an sglist large enough to hold all the
fragments.

However, for large packets with a lot of fragments, this isn't sufficient
and we need at least one additional fragment.

The problem manifests as skb_to_sgvec() returning -EMSGSIZE and this then
getting returned by userspace.  Most of the time, this isn't a problem as
rxrpc sets a limit of 5692, big enough for 4 jumbo subpackets to be glued
together; occasionally, however, the server will ignore the reported limit
and give a packet that's a lot bigger - say 19852 bytes with ->nr_frags
being 7.  skb_to_sgvec() then tries to return a "zeroth" fragment that
seems to occur before the fragments counted by ->nr_frags and we hit the
end of the sglist too early.

Note that __skb_to_sgvec() also has an skb_walk_frags() loop that is
recursive up to 24 deep.  I'm not sure if I need to take account of that
too - or if there's an easy way of counting those frags too.

Fix this by counting an extra frag and allocating a larger sglist based on
that.

Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Reported-by: Marc Dionne 
Signed-off-by: David Howells 
cc: linux-afs@lists.infradead.org
Signed-off-by: Sasha Levin

rxrpc: Fix decision on when to generate an IDLE ACK

2022-06-14T16:11:38+00:00

[ Upstream commit 9a3dedcf18096e8f7f22b8777d78c4acfdea1651 ]

Fix the decision on when to generate an IDLE ACK by keeping a count of the
number of packets we've received, but not yet soft-ACK'd, and the number of
packets we've processed, but not yet hard-ACK'd, rather than trying to keep
track of which DATA sequence numbers correspond to those points.

We then generate an ACK when either counter exceeds 2.  The counters are
both cleared when we transcribe the information into any sort of ACK packet
for transmission.  IDLE and DELAY ACKs are skipped if both counters are 0
(ie. no change).

Fixes: 805b21b929e2 ("rxrpc: Send an ACK after every few DATA packets we receive")
Signed-off-by: David Howells 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rxrpc: Don't let ack.previousPacket regress

2022-06-14T16:11:38+00:00

[ Upstream commit 81524b6312535897707f2942695da1d359a5e56b ]

The previousPacket field in the rx ACK packet should never go backwards -
it's now the highest DATA sequence number received, not the last on
received (it used to be used for out of sequence detection).

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rxrpc: Fix overlapping ACK accounting

2022-06-14T16:11:38+00:00

[ Upstream commit 8940ba3cfe4841928777fd45eaa92051522c7f0c ]

Fix accidental overlapping of Rx-phase ACK accounting with Tx-phase ACK
accounting through variables shared between the two.  call->acks_* members
refer to ACKs received in the Tx phase and call->ackr_* members to ACKs
sent/to be sent during the Rx phase.

Fixes: 1a2391c30c0b ("rxrpc: Fix detection of out of order acks")
Signed-off-by: David Howells 
cc: Jeffrey Altman 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rxrpc: Don't try to resend the request if we're receiving the reply

2022-06-14T16:11:38+00:00

[ Upstream commit 114af61f88fbe34d641b13922d098ffec4c1be1b ]

rxrpc has a timer to trigger resending of unacked data packets in a call.
This is not cancelled when a client call switches to the receive phase on
the basis that most calls don't last long enough for it to ever expire.
However, if it *does* expire after we've started to receive the reply, we
shouldn't then go into trying to retransmit or pinging the server to find
out if an ack got lost.

Fix this by skipping the resend code if we're into receiving the reply to a
client call.

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells 
cc: linux-afs@lists.infradead.org
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

rxrpc: Fix listen() setting the bar too high for the prealloc rings

2022-06-14T16:11:38+00:00

[ Upstream commit 88e22159750b0d55793302eeed8ee603f5c1a95c ]

AF_RXRPC's listen() handler lets you set the backlog up to 32 (if you bump
up the sysctl), but whilst the preallocation circular buffers have 32 slots
in them, one of them has to be a dead slot because we're using CIRC_CNT().

This means that listen(rxrpc_sock, 32) will cause an oops when the socket
is closed because rxrpc_service_prealloc_one() allocated one too many calls
and rxrpc_discard_prealloc() won't then be able to get rid of them because
it'll think the ring is empty.  rxrpc_release_calls_on_socket() then tries
to abort them, but oopses because call->peer isn't yet set.

Fix this by setting the maximum backlog to RXRPC_BACKLOG_MAX - 1 to match
the ring capacity.

 BUG: kernel NULL pointer dereference, address: 0000000000000086
 ...
 RIP: 0010:rxrpc_send_abort_packet+0x73/0x240 [rxrpc]
 Call Trace:
  
  ? __wake_up_common_lock+0x7a/0x90
  ? rxrpc_notify_socket+0x8e/0x140 [rxrpc]
  ? rxrpc_abort_call+0x4c/0x60 [rxrpc]
  rxrpc_release_calls_on_socket+0x107/0x1a0 [rxrpc]
  rxrpc_release+0xc9/0x1c0 [rxrpc]
  __sock_release+0x37/0xa0
  sock_close+0x11/0x20
  __fput+0x89/0x240
  task_work_run+0x59/0x90
  do_exit+0x319/0xaa0

Fixes: 00e907127e6f ("rxrpc: Preallocate peers, conns and calls for incoming service requests")
Reported-by: Marc Dionne 
Signed-off-by: David Howells 
cc: linux-afs@lists.infradead.org
Link: https://lists.infradead.org/pipermail/linux-afs/2022-March/005079.html
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin