tree 0944eefed2d209e9bd7ccbdebebedf367757f61a
parent 04d36d748fac349b068ef621611f454010054c58
author David Howells <dhowells@redhat.com> 1580421036 +0000
committer David Howells <dhowells@redhat.com> 1580725530 +0000

rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect

When a call is disconnected, the connection pointer from the call is
cleared to make sure it isn't used again and to prevent further attempted
transmission for the call.  Unfortunately, there might be a daemon trying
to use it at the same time to transmit a packet.

Fix this by keeping call->conn set, but setting a flag on the call to
indicate disconnection instead.

Remove also the bits in the transmission functions where the conn pointer is
checked and a ref taken under spinlock as this is now redundant.

Fixes: 8d94aa381dab ("rxrpc: Calls shouldn't hold socket refs")
Signed-off-by: David Howells <dhowells@redhat.com>