From 0eb362d254814ce04848730bf32e75b8ee1a4d6c Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 28 Apr 2023 21:27:55 +0100 Subject: [PATCH] rxrpc: Make it so that a waiting process can be aborted When sendmsg() creates an rxrpc call, it queues it to wait for a connection and channel to be assigned and then waits before it can start shovelling data as the encrypted DATA packet content includes a summary of the connection parameters. However, sendmsg() may get interrupted before a connection gets assigned and further sendmsg() calls will fail with EBUSY until an assignment is made. Fix this so that the call can at least be aborted without failing on EBUSY. We have to be careful here as sendmsg() mustn't be allowed to start the call timer if the call doesn't yet have a connection assigned as an oops may follow shortly thereafter. Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg") Reported-by: Marc Dionne Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller --- net/rxrpc/sendmsg.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c index 7498a77..c1b074c 100644 --- a/net/rxrpc/sendmsg.c +++ b/net/rxrpc/sendmsg.c @@ -656,10 +656,13 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len) goto out_put_unlock; } else { switch (rxrpc_call_state(call)) { - case RXRPC_CALL_UNINITIALISED: case RXRPC_CALL_CLIENT_AWAIT_CONN: - case RXRPC_CALL_SERVER_PREALLOC: case RXRPC_CALL_SERVER_SECURING: + if (p.command == RXRPC_CMD_SEND_ABORT) + break; + fallthrough; + case RXRPC_CALL_UNINITIALISED: + case RXRPC_CALL_SERVER_PREALLOC: rxrpc_put_call(call, rxrpc_call_put_sendmsg); ret = -EBUSY; goto error_release_sock; -- 2.7.4