path: root/net/rxrpc/conn_object.c
diff options
authorDavid Howells <dhowells@redhat.com>2020-02-06 13:55:01 +0000
committerDavid S. Miller <davem@davemloft.net>2020-02-07 11:19:38 +0100
commitb39a934ec72fa2b5a74123891f25273a38378b90 (patch)
tree5379ccc45be371b09cd4ac292ff8c2b2724edb04 /net/rxrpc/conn_object.c
parentMerge tag 'mlx5-fixes-2020-02-06' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux (diff)
rxrpc: Fix service call disconnection
The recent patch that substituted a flag on an rxrpc_call for the connection pointer being NULL as an indication that a call was disconnected puts the set_bit in the wrong place for service calls. This is only a problem if a call is implicitly terminated by a new call coming in on the same connection channel instead of a terminating ACK packet. In such a case, rxrpc_input_implicit_end_call() calls __rxrpc_disconnect_call(), which is now (incorrectly) setting the disconnection bit, meaning that when rxrpc_release_call() is later called, it doesn't call rxrpc_disconnect_call() and so the call isn't removed from the peer's error distribution list and the list gets corrupted. KASAN finds the issue as an access after release on a call, but the position at which it occurs is confusing as it appears to be related to a different call (the call site is where the latter call is being removed from the error distribution list and either the next or pprev pointer points to a previously released call). Fix this by moving the setting of the flag from __rxrpc_disconnect_call() to rxrpc_disconnect_call() in the same place that the connection pointer was being cleared. Fixes: 5273a191dca6 ("rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 1 insertions, 2 deletions
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index c0b3154f7a7e..19e141eeed17 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -171,8 +171,6 @@ void __rxrpc_disconnect_call(struct rxrpc_connection *conn,
_enter("%d,%x", conn->debug_id, call->cid);
- set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
if (rcu_access_pointer(chan->call) == call) {
/* Save the result of the call so that we can repeat it if necessary
* through the channel, whilst disposing of the actual call record.
@@ -225,6 +223,7 @@ void rxrpc_disconnect_call(struct rxrpc_call *call)
__rxrpc_disconnect_call(conn, call);
+ set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
conn->idle_timestamp = jiffies;