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| author | Andres Beltran <lkmlabelt@gmail.com> | 2021-04-08 19:14:39 +0300 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2021-05-14 20:37:46 +0300 |
| commit | adae1e931acd8b430d31141a283ea06d4b705417 (patch) | |
| tree | 70799e7f212ce0f991b0a675625391b8adf606f3 /drivers/scsi/storvsc_drv.c | |
| parent | 03b30cc38dd3c3521dafb1cb2ac4ecd8470bbf0a (diff) | |
| download | linux-adae1e931acd8b430d31141a283ea06d4b705417.tar.xz | |
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>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210408161439.341988-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
| -rw-r--r-- | drivers/scsi/storvsc_drv.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index e6718a74e5da..07149fa72b68 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -406,6 +406,14 @@ static void storvsc_on_channel_callback(void *context); #define STORVSC_IDE_MAX_TARGETS 1 #define STORVSC_IDE_MAX_CHANNELS 1 +/* + * Upper bound on the size of a storvsc packet. vmscsi_size_delta is not + * included in the calculation because it is set after STORVSC_MAX_PKT_SIZE + * is used in storvsc_connect_to_vsp + */ +#define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\ + sizeof(struct vstor_packet)) + struct storvsc_cmd_request { struct scsi_cmnd *cmd; @@ -701,6 +709,7 @@ static void handle_sc_creation(struct vmbus_channel *new_sc) return; memset(&props, 0, sizeof(struct vmstorage_channel_properties)); + new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE; /* * The size of vmbus_requestor is an upper bound on the number of requests @@ -1294,6 +1303,7 @@ static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size, memset(&props, 0, sizeof(struct vmstorage_channel_properties)); + device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE; /* * The size of vmbus_requestor is an upper bound on the number of requests * that can be in-progress at any one time across all channels. |