rxrpc: Fix overwaking on call poking

If an rxrpc call is given a poke, it will get woken up unconditionally, even if there's already a poke pending (for which there will have been a wake) or if the call refcount has gone to 0. Fix this by only waking the call if it is still referenced and if it doesn't already have a poke pending. Fixes: 15f661d ("rxrpc: Implement a mechanism to send an event notification to a call") Signed-off-by: David Howells <[email protected]> cc: Marc Dionne <[email protected]> cc: [email protected]
wafgo · Feb 7, 2023 · a33395a · a33395a
1 parent 16d5677
commit a33395a
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
@@ -54,12 +54,14 @@ void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
 		spin_lock_bh(&local->lock);
 		busy = !list_empty(&call->attend_link);
 		trace_rxrpc_poke_call(call, busy, what);
+		if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
+			busy = true;
 		if (!busy) {
-			rxrpc_get_call(call, rxrpc_call_get_poke);
 			list_add_tail(&call->attend_link, &local->call_attend_q);
 		}
 		spin_unlock_bh(&local->lock);
-		rxrpc_wake_up_io_thread(local);
+		if (!busy)
+			rxrpc_wake_up_io_thread(local);
 	}
 }