[PATCH AUTOSEL 4.14 10/15] rxrpc: Fix connection-level abort handling

Sasha Levin
2018-10-22T10:20:21Z

From: David Howells <dhowells@redhat.com>

[ Upstream commit 647530924f47c93db472ee3cf43b7ef1425581b6 ]

Fix connection-level abort handling to cache the abort and error codes
properly so that a new incoming call can be properly aborted if it races
with the parent connection being aborted by another CPU.

The abort_code and error parameters can then be dropped from
rxrpc_abort_calls().

Fixes: f5c17aaeb2ae ("rxrpc: Calls should only have one terminal state")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/rxrpc/ar-internal.h | 4 ++--
net/rxrpc/call_accept.c | 4 ++--
net/rxrpc/conn_event.c | 26 +++++++++++++++-----------
3 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index e6c2c4f56fb1..71c7f1dd4599 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -424,8 +424,7 @@ struct rxrpc_connection {
spinlock_t state_lock; /* state-change lock */
enum rxrpc_conn_cache_state cache_state;
enum rxrpc_conn_proto_state state; /* current state of connection */
- u32 local_abort; /* local abort code */
- u32 remote_abort; /* remote abort code */
+ u32 abort_code; /* Abort code of connection abort */
int debug_id; /* debug ID for printks */
atomic_t serial; /* packet serial number counter */
unsigned int hi_serial; /* highest serial number received */
@@ -435,6 +434,7 @@ struct rxrpc_connection {
u8 security_size; /* security header size */
u8 security_ix; /* security type */
u8 out_clientflag; /* RXRPC_CLIENT_INITIATED if we are client */
+ short error; /* Local error code */
};

/*
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c
index 62b1581d44a5..2dd13f5c47c8 100644
--- a/net/rxrpc/call_accept.c
+++ b/net/rxrpc/call_accept.c
@@ -418,11 +418,11 @@ struct rxrpc_call *rxrpc_new_incoming_call(struct rxrpc_local *local,

case RXRPC_CONN_REMOTELY_ABORTED:
rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
- conn->remote_abort, -ECONNABORTED);
+ conn->abort_code, conn->error);
break;
case RXRPC_CONN_LOCALLY_ABORTED:
rxrpc_abort_call("CON", call, sp->hdr.seq,
- conn->local_abort, -ECONNABORTED);
+ conn->abort_code, conn->error);
break;
default:
BUG();
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 0435c4167a1a..75ec1ad595b7 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -117,7 +117,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,

switch (chan->last_type) {
case RXRPC_PACKET_TYPE_ABORT:
- _proto("Tx ABORT %%%u { %d } [re]", serial, conn->local_abort);
+ _proto("Tx ABORT %%%u { %d } [re]", serial, conn->abort_code);
break;
case RXRPC_PACKET_TYPE_ACK:
trace_rxrpc_tx_ack(NULL, serial, chan->last_seq, 0,
@@ -135,13 +135,12 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
* pass a connection-level abort onto all calls on that connection
*/
static void rxrpc_abort_calls(struct rxrpc_connection *conn,
- enum rxrpc_call_completion compl,
- u32 abort_code, int error)
+ enum rxrpc_call_completion compl)
{
struct rxrpc_call *call;
int i;

- _enter("{%d},%x", conn->debug_id, abort_code);
+ _enter("{%d},%x", conn->debug_id, conn->abort_code);

spin_lock(&conn->channel_lock);

@@ -153,9 +152,11 @@ static void rxrpc_abort_calls(struct rxrpc_connection *conn,
if (compl == RXRPC_CALL_LOCALLY_ABORTED)
trace_rxrpc_abort("CON", call->cid,
call->call_id, 0,
- abort_code, error);
+ conn->abort_code,
+ conn->error);
if (rxrpc_set_call_completion(call, compl,
- abort_code, error))
+ conn->abort_code,
+ conn->error))
rxrpc_notify_socket(call);
}
}
@@ -188,10 +189,12 @@ static int rxrpc_abort_connection(struct rxrpc_connection *conn,
return 0;
}

+ conn->error = error;
+ conn->abort_code = abort_code;
conn->state = RXRPC_CONN_LOCALLY_ABORTED;
spin_unlock_bh(&conn->state_lock);

- rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code, error);
+ rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED);

msg.msg_name = &conn->params.peer->srx.transport;
msg.msg_namelen = conn->params.peer->srx.transport_len;
@@ -210,7 +213,7 @@ static int rxrpc_abort_connection(struct rxrpc_connection *conn,
whdr._rsvd = 0;
whdr.serviceId = htons(conn->service_id);

- word = htonl(conn->local_abort);
+ word = htonl(conn->abort_code);

iov[0].iov_base = &whdr;
iov[0].iov_len = sizeof(whdr);
@@ -221,7 +224,7 @@ static int rxrpc_abort_connection(struct rxrpc_connection *conn,

serial = atomic_inc_return(&conn->serial);
whdr.serial = htonl(serial);
- _proto("Tx CONN ABORT %%%u { %d }", serial, conn->local_abort);
+ _proto("Tx CONN ABORT %%%u { %d }", serial, conn->abort_code);

ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
if (ret < 0) {
@@ -289,9 +292,10 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
abort_code = ntohl(wtmp);
_proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);

+ conn->error = -ECONNABORTED;
+ conn->abort_code = abort_code;
conn->state = RXRPC_CONN_REMOTELY_ABORTED;
- rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED,
- abort_code, -ECONNABORTED);
+ rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED);
return -ECONNABORTED;

case RXRPC_PACKET_TYPE_CHALLENGE:
--
2.17.1