From: Stefano Garzarella <sgarzare@redhat.com> stable inclusion from stable-v6.6.142 commit ce29d3bf79a265c12113885c92900044985ef18b category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15870 CVE: CVE-2026-53132 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit a4f0b001782b21663d10df983b4b208195bec66c upstream. 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 <sgarzare@redhat.com> Link: https://patch.msgid.link/20260518090656.134588-2-sgarzare@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> --- net/vmw_vsock/virtio_transport_common.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 66c3ac299bdd..3d171d41e2ac 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1166,7 +1166,7 @@ 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) { @@ -1181,10 +1181,8 @@ 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++; @@ -1222,6 +1220,8 @@ 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 @@ -1234,7 +1234,17 @@ 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: -- 2.43.0