Re: [PATCH] scsi: storvsc: be more picky about scmnd->sc_data_direction

Vitaly Kuznetsov
2015-08-13T08:53:54Z

KY Srinivasan <kys@microsoft.com> writes:

>> -----Original Message-----
>> From: Vitaly Kuznetsov [mailto:vkuznets@redhat.com]
>> Sent: Thursday, June 25, 2015 9:12 AM
>> To: linux-scsi@vger.kernel.org
>> Cc: Long Li; KY Srinivasan; Haiyang Zhang; James E.J. Bottomley;
>> devel@linuxdriverproject.org; linux-kernel@vger.kernel.org; Radim Krčmář
>> Subject: [PATCH] scsi: storvsc: be more picky about scmnd-
>> >sc_data_direction
>>
>> Under the 'default' case in scmnd->sc_data_direction we have 3 options:
>> - DMA_NONE which we handle correctly.
>> - DMA_BIDIRECTIONAL which is never supposed to be set by SCSI stack.
>> - Garbage value.
>>
>> Do WARN() and return -EINVAL in the last two cases. virtio_scsi does
>> BUG_ON() here but it looks like an overkill.
>>
>> Reported-by: Radim Krčmář <rkrcmar@redhat.com>
>> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>

Sorry for the ping but it seems the fix never made it to scsi tree...

>> ---
>> drivers/scsi/storvsc_drv.c | 10 +++++++++-
>> 1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
>> index 3c6584f..61f4855 100644
>> --- a/drivers/scsi/storvsc_drv.c
>> +++ b/drivers/scsi/storvsc_drv.c
>> @@ -1598,10 +1598,18 @@ static int storvsc_queuecommand(struct
>> Scsi_Host *host, struct scsi_cmnd *scmnd)
>> vm_srb->data_in = READ_TYPE;
>> vm_srb->win8_extension.srb_flags |=
>> SRB_FLAGS_DATA_IN;
>> break;
>> - default:
>> + case DMA_NONE:
>> vm_srb->data_in = UNKNOWN_TYPE;
>> vm_srb->win8_extension.srb_flags |=
>> SRB_FLAGS_NO_DATA_TRANSFER;
>> break;
>> + default:
>> + /*
>> + * This is DMA_BIDIRECTIONAL or something else we are
>> never
>> + * supposed to see here.
>> + */
>> + WARN(1, "Unexpected data direction: %d\n",
>> + scmnd->sc_data_direction);
>> + return -EINVAL;
>> }
>>
>>
>> --
>> 2.4.3

--
Vitaly