From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B7E92305678 for ; Thu, 28 May 2026 10:00:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779962436; cv=none; b=B5zEsUPDWRVicjP75DLRAGb5HG15Te3z2184QsjI4zN7bw8na2pAiLXa+6SxQOzHSUKhiA4gRneS8UNzB1ATQuojvFJt1khPxgD/nrRTnO8+zu6DMZ6c1QdOMB6igb9bS4nTeZ4mDYfW1x6bvR8ShssNTlpEKEflOcn8XwWNJyo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779962436; c=relaxed/simple; bh=Q6wf5Xibhdg8bY+2XRpDXJNFamzNAinAhWrs6FN6Jq0=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=IbQZGy+ygwK7Skly8wvRKy8ka7wGJmrKfM9OhtdT7tYMI0Iuf+8y9TOKdNBl4qz/MLIn4BfsGPRpWaURoE1RFWsjC16+yEkCgyYbdJWHPZ8wrcXawkUZihygAUXwiGpWgmvISwVel6duDidNBC6qhQRM5SVFGe13c40dk/7dKmk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KeWT9LYn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="KeWT9LYn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2FE51F000E9; Thu, 28 May 2026 10:00:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779962435; bh=Jo8ko4ont4IPCzwhD1+Qd+wm/qjqFadBxA4aKEJz0TQ=; h=Subject:To:Cc:From:Date; b=KeWT9LYnTXPocrsjdv8Q7W7WfiVzSgwcJns+Bp13trHpVHCmmclYxjHnPaOJX1K7S L3mfdJ1wlKRze17eHP6gGa+w84yU5yclDy6pop/bM+gV1IOif2qwUucHGx1TJDmvK0 zTvtiBWZLTpIfoN0LtD+ymfipDv2QtvO+GVXXLog= Subject: FAILED: patch "[PATCH] vsock/virtio: reset connection on receiving queue overflow" failed to apply to 5.15-stable tree To: sgarzare@redhat.com,pabeni@redhat.com Cc: From: Date: Thu, 28 May 2026 11:59:41 +0200 Message-ID: <2026052841-mobility-surgery-8063@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x a4f0b001782b21663d10df983b4b208195bec66c # git commit -s git send-email --to '' --in-reply-to '2026052841-mobility-surgery-8063@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From a4f0b001782b21663d10df983b4b208195bec66c Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Mon, 18 May 2026 11:06:55 +0200 Subject: [PATCH] vsock/virtio: reset connection on receiving queue overflow When there is no more space to queue an incoming packet, the packet is silently dropped. This causes data loss without any notification to either peer, since there is no retransmission. Under normal circumstances, this should never happen. However, it could happen if the other peer doesn't respect the credit, or if the skb overhead, which we recently began to take into account with commit 059b7dbd20a6 ("vsock/virtio: fix potential unbounded skb queue"), is too high. Fix this by resetting the connection and setting the local socket error to ENOBUFS when virtio_transport_recv_enqueue() can no longer queue a packet, so both peers are explicitly notified of the failure rather than silently losing data. Fixes: ae6fcfbf5f03 ("vsock/virtio: discard packets if credit is not respected") Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella Link: https://patch.msgid.link/20260518090656.134588-2-sgarzare@redhat.com Signed-off-by: Paolo Abeni diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 1e3409d28164..5028ff534888 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1335,7 +1335,7 @@ virtio_transport_recv_connecting(struct sock *sk, return err; } -static void +static bool virtio_transport_recv_enqueue(struct vsock_sock *vsk, struct sk_buff *skb) { @@ -1350,10 +1350,8 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk, spin_lock_bh(&vvs->rx_lock); can_enqueue = virtio_transport_inc_rx_pkt(vvs, len); - if (!can_enqueue) { - free_pkt = true; + if (!can_enqueue) goto out; - } if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOM) vvs->msg_count++; @@ -1393,6 +1391,8 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk, spin_unlock_bh(&vvs->rx_lock); if (free_pkt) kfree_skb(skb); + + return can_enqueue; } static int @@ -1405,7 +1405,17 @@ virtio_transport_recv_connected(struct sock *sk, switch (le16_to_cpu(hdr->op)) { case VIRTIO_VSOCK_OP_RW: - virtio_transport_recv_enqueue(vsk, skb); + if (!virtio_transport_recv_enqueue(vsk, skb)) { + /* There is no more space to queue the packet, so let's + * close the connection; otherwise, we'll lose data. + */ + (void)virtio_transport_reset(vsk, skb); + virtio_transport_do_close(vsk, true); + sk->sk_err = ENOBUFS; + sk_error_report(sk); + vsock_remove_sock(vsk); + break; + } vsock_data_ready(sk); return err; case VIRTIO_VSOCK_OP_CREDIT_REQUEST: