From a8c3209998afb5c4941b49e35b513cea9050cb4a Mon Sep 17 00:00:00 2001 From: Andres Beltran <lkmlabelt@gmail.com> Date: Tue, 8 Dec 2020 05:53:11 +0100 Subject: Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer Pointers to ring-buffer packets sent by Hyper-V are used within the guest VM. Hyper-V can send packets with erroneous values or modify packet fields after they are processed by the guest. To defend against these scenarios, return a copy of the incoming VMBus packet after validating its length and offset fields in hv_pkt_iter_first(). In this way, the packet can no longer be modified by the host. Signed-off-by: Andres Beltran <lkmlabelt@gmail.com> Co-developed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: netdev@vger.kernel.org Cc: linux-scsi@vger.kernel.org Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20201208045311.10244-1-parri.andrea@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org> --- drivers/net/hyperv/hyperv_net.h | 3 +++ drivers/net/hyperv/netvsc.c | 2 ++ drivers/net/hyperv/rndis_filter.c | 2 ++ 3 files changed, 7 insertions(+) (limited to 'drivers/net/hyperv') diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index 2a87cfa27ac0..7ea6936f86ef 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -860,9 +860,12 @@ static inline u32 netvsc_rqstor_size(unsigned long ringbytes) ringbytes / NETVSC_MIN_IN_MSG_SIZE; } +#define NETVSC_MAX_XFER_PAGE_RANGES 375 #define NETVSC_XFER_HEADER_SIZE(rng_cnt) \ (offsetof(struct vmtransfer_page_packet_header, ranges) + \ (rng_cnt) * sizeof(struct vmtransfer_page_range)) +#define NETVSC_MAX_PKT_SIZE (NETVSC_XFER_HEADER_SIZE(NETVSC_MAX_XFER_PAGE_RANGES) + \ + sizeof(struct nvsp_message) + (sizeof(u32) * VRSS_SEND_TAB_SIZE)) struct multi_send_data { struct sk_buff *skb; /* skb containing the pkt */ diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 2350342b961f..1510a236aa34 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -1530,6 +1530,8 @@ struct netvsc_device *netvsc_device_add(struct hv_device *device, /* Open the channel */ device->channel->rqstor_size = netvsc_rqstor_size(netvsc_ring_bytes); + device->channel->max_pkt_size = NETVSC_MAX_PKT_SIZE; + ret = vmbus_open(device->channel, netvsc_ring_bytes, netvsc_ring_bytes, NULL, 0, netvsc_channel_cb, net_device->chan_table); diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 598713c0d5a8..7e6dee2f02a4 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -1174,6 +1174,8 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc) nvchan->channel = new_sc; new_sc->rqstor_size = netvsc_rqstor_size(netvsc_ring_bytes); + new_sc->max_pkt_size = NETVSC_MAX_PKT_SIZE; + ret = vmbus_open(new_sc, netvsc_ring_bytes, netvsc_ring_bytes, NULL, 0, netvsc_channel_cb, nvchan); -- cgit v1.2.3-70-g09d2