[PATCH net v3 05/11] rxrpc: Fix call removal to use RCU safe deletion

[David Howells <dhowells@redhat.com>]

Fix rxrpc call removal from the rxnet->calls list to use list_del_rcu()
rather than list_del_init() to prevent stuffing up reading
/proc/net/rxrpc/calls from potentially getting into an infinite loop.

Closes: https://sashiko.dev/#/patchset/20260319150150.4189381-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
cc: stable@kernel.org
---
 net/rxrpc/call_object.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 918f41d97a2f..0e47751d5937 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -654,9 +654,9 @@ void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 	if (dead) {
 		ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 
-		if (!list_empty(&call->link)) {
+		if (on_list_rcu(&call->link)) {
 			spin_lock(&rxnet->call_lock);
-			list_del_init(&call->link);
+			list_del_rcu(&call->link);
 			spin_unlock(&rxnet->call_lock);
 		}
 
@@ -738,7 +738,7 @@ void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 			_debug("Zapping call %p", call);
 
 			rxrpc_see_call(call, rxrpc_call_see_zap);
-			list_del_init(&call->link);
+			list_del_rcu(&call->link);
 
 			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
 			       call, refcount_read(&call->ref),