linux/net/rxrpc
David Howells 4ba68c5192 rxrpc: Return an error to sendmsg if call failed
If at the end of rxrpc sendmsg() or rxrpc_kernel_send_data() the call that
was being given data was aborted remotely or otherwise failed, return an
error rather than returning the amount of data buffered for transmission.

The call (presumably) did not complete, so there's not much point
continuing with it.  AF_RXRPC considers it "complete" and so will be
unwilling to do anything else with it - and won't send a notification for
it, deeming the return from sendmsg sufficient.

Not returning an error causes afs to incorrectly handle a StoreData
operation that gets interrupted by a change of address due to NAT
reconfiguration.

This doesn't normally affect most operations since their request parameters
tend to fit into a single UDP packet and afs_make_call() returns before the
server responds; StoreData is different as it involves transmission of a
lot of data.

This can be triggered on a client by doing something like:

	dd if=/dev/zero of=/afs/example.com/foo bs=1M count=512

at one prompt, and then changing the network address at another prompt,
e.g.:

	ifconfig enp6s0 inet 192.168.6.2 && route add 192.168.6.1 dev enp6s0

Tracing packets on an Auristor fileserver looks something like:

192.168.6.1 -> 192.168.6.3  RX 107 ACK Idle  Seq: 0  Call: 4  Source Port: 7000  Destination Port: 7001
192.168.6.3 -> 192.168.6.1  AFS (RX) 1482 FS Request: Unknown(64538) (64538)
192.168.6.3 -> 192.168.6.1  AFS (RX) 1482 FS Request: Unknown(64538) (64538)
192.168.6.1 -> 192.168.6.3  RX 107 ACK Idle  Seq: 0  Call: 4  Source Port: 7000  Destination Port: 7001
<ARP exchange for 192.168.6.2>
192.168.6.2 -> 192.168.6.1  AFS (RX) 1482 FS Request: Unknown(0) (0)
192.168.6.2 -> 192.168.6.1  AFS (RX) 1482 FS Request: Unknown(0) (0)
192.168.6.1 -> 192.168.6.2  RX 107 ACK Exceeds Window  Seq: 0  Call: 4  Source Port: 7000  Destination Port: 7001
192.168.6.1 -> 192.168.6.2  RX 74 ABORT  Seq: 0  Call: 4  Source Port: 7000  Destination Port: 7001
192.168.6.1 -> 192.168.6.2  RX 74 ABORT  Seq: 29321  Call: 4  Source Port: 7000  Destination Port: 7001

The Auristor fileserver logs code -453 (RXGEN_SS_UNMARSHAL), but the abort
code received by kafs is -5 (RX_PROTOCOL_ERROR) as the rx layer sees the
condition and generates an abort first and the unmarshal error is a
consequence of that at the application layer.

Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-afs@lists.infradead.org
Link: http://lists.infradead.org/pipermail/linux-afs/2021-December/004810.html # v1
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-22 21:03:02 +01:00
..
af_rxrpc.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
ar-internal.h rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
call_accept.c rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
call_event.c rxrpc: Fix call timer start racing with call destruction 2022-03-31 12:25:25 +02:00
call_object.c rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
conn_client.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
conn_event.c rxrpc: Merge prime_packet_security into init_connection_security 2020-11-23 18:09:30 +00:00
conn_object.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
conn_service.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
input.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
insecure.c rxrpc: Ask the security class how much space to allow in a packet 2020-11-23 19:53:11 +00:00
Kconfig net: RxRPC: make dependent Kconfig symbols be shown indented 2021-08-18 10:12:11 +01:00
key.c rxrpc: Fix handling of an unsupported token type in rxrpc_read() 2021-01-13 10:38:00 -08:00
local_event.c rxrpc: Fix a typo 2021-06-02 14:01:55 -07:00
local_object.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
Makefile rxrpc: Split the server key type (rxrpc_s) into its own file 2020-11-23 18:09:29 +00:00
misc.c rxrpc: Fix the excessive initial retransmission timeout 2020-05-11 16:42:28 +01:00
net_ns.c rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
output.c rxrpc: Adjust retransmission backoff 2022-01-22 02:03:24 +00:00
peer_event.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
peer_object.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
proc.c rxrpc: Fix locking issue 2022-05-22 21:03:01 +01:00
protocol.h rxrpc: Improve jumbo packet counting 2019-08-27 09:48:37 +01:00
recvmsg.c afs: Don't truncate iter during data fetch 2021-04-23 10:17:26 +01:00
rtt.c rxrpc: Fix _usecs_to_jiffies() by using usecs_to_jiffies() 2021-09-24 14:18:34 +01:00
rxkad.c rxrpc: rxkad: Remove redundant variable offset 2021-04-27 14:05:06 -07:00
security.c rxrpc: Hand server key parsing off to the security class 2020-11-23 18:09:29 +00:00
sendmsg.c rxrpc: Return an error to sendmsg if call failed 2022-05-22 21:03:02 +01:00
server_key.c rxrpc: fix some null-ptr-deref bugs in server_key.c 2022-03-31 15:21:31 +02:00
skbuff.c rxrpc: Use refcount_t rather than atomic_t 2022-05-22 21:03:01 +01:00
sysctl.c rxrpc: Rewrite the client connection manager 2020-09-08 21:11:43 +01:00
utils.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00