From: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx> [ Upstream commit 6fd13d699d24beaa28310848fe65fd898fbb9043 ] The validation on the length of incoming packets performed in storvsc_on_channel_callback() does not apply to unsolicited packets with ID of 0 sent by Hyper-V. Adjust the validation for such unsolicited packets. Link: https://lore.kernel.org/r/20211007122828.469289-1-parri.andrea@xxxxxxxxx Fixes: 91b1b640b834b2 ("scsi: storvsc: Validate length of incoming packet in storvsc_on_channel_callback()") Reported-by: Dexuan Cui <decui@xxxxxxxxxxxxx> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/storvsc_drv.c | 32 +++++++++++++++++++++++--------- 1 file changed, 23 insertions(+), 9 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 37506b3fe5a9..5fa1120a87f7 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -1285,11 +1285,15 @@ static void storvsc_on_channel_callback(void *context) foreach_vmbus_pkt(desc, channel) { struct vstor_packet *packet = hv_pkt_data(desc); struct storvsc_cmd_request *request = NULL; + u32 pktlen = hv_pkt_datalen(desc); u64 rqst_id = desc->trans_id; + u32 minlen = rqst_id ? sizeof(struct vstor_packet) - + stor_device->vmscsi_size_delta : sizeof(enum vstor_packet_operation); - if (hv_pkt_datalen(desc) < sizeof(struct vstor_packet) - - stor_device->vmscsi_size_delta) { - dev_err(&device->device, "Invalid packet len\n"); + if (pktlen < minlen) { + dev_err(&device->device, + "Invalid pkt: id=%llu, len=%u, minlen=%u\n", + rqst_id, pktlen, minlen); continue; } @@ -1302,13 +1306,23 @@ static void storvsc_on_channel_callback(void *context) if (rqst_id == 0) { /* * storvsc_on_receive() looks at the vstor_packet in the message - * from the ring buffer. If the operation in the vstor_packet is - * COMPLETE_IO, then we call storvsc_on_io_completion(), and - * dereference the guest memory address. Make sure we don't call - * storvsc_on_io_completion() with a guest memory address that is - * zero if Hyper-V were to construct and send such a bogus packet. + * from the ring buffer. + * + * - If the operation in the vstor_packet is COMPLETE_IO, then + * we call storvsc_on_io_completion(), and dereference the + * guest memory address. Make sure we don't call + * storvsc_on_io_completion() with a guest memory address + * that is zero if Hyper-V were to construct and send such + * a bogus packet. + * + * - If the operation in the vstor_packet is FCHBA_DATA, then + * we call cache_wwn(), and access the data payload area of + * the packet (wwn_packet); however, there is no guarantee + * that the packet is big enough to contain such area. + * Future-proof the code by rejecting such a bogus packet. */ - if (packet->operation == VSTOR_OPERATION_COMPLETE_IO) { + if (packet->operation == VSTOR_OPERATION_COMPLETE_IO || + packet->operation == VSTOR_OPERATION_FCHBA_DATA) { dev_err(&device->device, "Invalid packet with ID of 0\n"); continue; } -- 2.33.0
