scsi: storvsc: Set correct data length for sending SCSI command without payload

In StorVSC, payload->range.len is used to indicate if this SCSI command
carries payload. This data is allocated as part of the private driver data
by the upper layer and may get passed to lower driver uninitialized.

For example, the SCSI error handling mid layer may send TEST_UNIT_READY or
REQUEST_SENSE while reusing the buffer from a failed command. The private
data section may have stale data from the previous command.

If the SCSI command doesn't carry payload, the driver may use this value as
is for communicating with host, resulting in possible corruption.

Fix this by always initializing this value.

Fixes: be0cf6ca301c ("scsi: storvsc: Set the tablesize based on the information given by the host")
Cc: stable@kernel.org
Tested-by: Roman Kisel <romank@linux.microsoft.com>
Reviewed-by: Roman Kisel <romank@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Long Li <longli@microsoft.com>
Link: https://lore.kernel.org/r/1737601642-7759-1-git-send-email-longli@linuxonhyperv.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 5a101ac06c478aad9b01072e7a6c5af48219f5c8..a8614e54544e59d4391ae8c2cf5682c5cfe74c08 100644 (file)
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1800,6 +1800,7 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
 
        length = scsi_bufflen(scmnd);
        payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
+       payload->range.len = 0;
        payload_sz = 0;
 
        if (scsi_sg_count(scmnd)) {