mptcp: leverage skb deferral free

[ Upstream commit 9aa59323f2709370cb4f01acbba599a9167f317b ]

Usage of the skb deferral API is straight-forward; with multiple
subflows actives this allow moving part of the received application
load into multiple CPUs.

Also fix a typo in the related comment.

Reviewed-by: Geliang Tang <geliang@kernel.org>
Tested-by: Geliang Tang <geliang@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250927-net-next-mptcp-rcv-path-imp-v1-1-5da266aa9c1a@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 8e04ce45a8db ("mptcp: fix MSG_PEEK stream corruption")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index a25dcdf748ca754d0b7c38be0dbf158d6cc08ca7..e4398ee9b55ac82391feb92861693ed6a19a653a 100644 (file)
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1934,12 +1934,13 @@ static int __mptcp_recvmsg_mskq(struct sock *sk,
                }
 
                if (!(flags & MSG_PEEK)) {
-                       /* avoid the indirect call, we know the destructor is sock_wfree */
+                       /* avoid the indirect call, we know the destructor is sock_rfree */
                        skb->destructor = NULL;
+                       skb->sk = NULL;
                        atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
                        sk_mem_uncharge(sk, skb->truesize);
                        __skb_unlink(skb, &sk->sk_receive_queue);
-                       __kfree_skb(skb);
+                       skb_attempt_defer_free(skb);
                        msk->bytes_consumed += count;
                }