From: Will Deacon <will@kernel.org> mainline inclusion from mainline-v6.17-rc1 commit 0dab92484474587b82e8e0455839eaf5ac7bf894 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICWO1M CVE: CVE-2025-39718 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- When receiving a vsock packet in the guest, only the virtqueue buffer size is validated prior to virtio_vsock_skb_rx_put(). Unfortunately, virtio_vsock_skb_rx_put() uses the length from the packet header as the length argument to skb_put(), potentially resulting in SKB overflow if the host has gone wonky. Validate the length as advertised by the packet header before calling virtio_vsock_skb_rx_put(). Cc: <stable@vger.kernel.org> Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") Signed-off-by: Will Deacon <will@kernel.org> Message-Id: <20250717090116.11987-3-will@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Ziming Du <duziming2@huawei.com> --- net/vmw_vsock/virtio_transport.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c index 2925f5d27ad3f..c4877cb7a5737 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -497,8 +497,9 @@ static void virtio_transport_rx_work(struct work_struct *work) do { virtqueue_disable_cb(vq); for (;;) { + unsigned int len, payload_len; + struct virtio_vsock_hdr *hdr; struct sk_buff *skb; - unsigned int len; if (!virtio_transport_more_replies(vsock)) { /* Stop rx until the device processes already @@ -515,12 +516,19 @@ static void virtio_transport_rx_work(struct work_struct *work) vsock->rx_buf_nr--; /* Drop short/long packets */ - if (unlikely(len < sizeof(struct virtio_vsock_hdr) || + if (unlikely(len < sizeof(*hdr) || len > virtio_vsock_skb_len(skb))) { kfree_skb(skb); continue; } + hdr = virtio_vsock_hdr(skb); + payload_len = le32_to_cpu(hdr->len); + if (unlikely(payload_len > len - sizeof(*hdr))) { + kfree_skb(skb); + continue; + } + virtio_vsock_skb_rx_put(skb); virtio_transport_deliver_tap_pkt(skb); virtio_transport_recv_pkt(&virtio_transport, skb); -- 2.43.0