scsi: core: Treat device offline as a failure

When a SCSI device is offline a MODE SENSE command will return a result
with only DID_NO_CONNECT set. In sd_read_write_protect_flag() only the
status byte of the result is checked. Despite a returned status of
DID_NO_CONNECT the command is considered successful and we read
sdkp->write_prot from a buffer containing garbage.

Modify scsi_status_is_good() to treat DID_NO_CONNECT as a failure case.

Link: https://lore.kernel.org/r/20210330114727.234467-1-yanaijie@huawei.com
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Jason Yan 2021-03-30 19:47:27 +08:00 committed by Martin K. Petersen
parent 6efb943b86
commit 1ee2753422

View File

@ -30,32 +30,6 @@ enum scsi_timeouts {
*/
#define SCAN_WILD_CARD ~0
/** scsi_status_is_good - check the status return.
*
* @status: the status passed up from the driver (including host and
* driver components)
*
* This returns true for known good conditions that may be treated as
* command completed normally
*/
static inline int scsi_status_is_good(int status)
{
/*
* FIXME: bit0 is listed as reserved in SCSI-2, but is
* significant in SCSI-3. For now, we follow the SCSI-2
* behaviour and ignore reserved bits.
*/
status &= 0xfe;
return ((status == SAM_STAT_GOOD) ||
(status == SAM_STAT_CONDITION_MET) ||
/* Next two "intermediate" statuses are obsolete in SAM-4 */
(status == SAM_STAT_INTERMEDIATE) ||
(status == SAM_STAT_INTERMEDIATE_CONDITION_MET) ||
/* FIXME: this is obsolete in SAM-3 */
(status == SAM_STAT_COMMAND_TERMINATED));
}
/*
* standard mode-select header prepended to all mode-select commands
*/
@ -277,4 +251,32 @@ enum scsi_disposition {
/* Used to obtain the PCI location of a device */
#define SCSI_IOCTL_GET_PCI 0x5387
/** scsi_status_is_good - check the status return.
*
* @status: the status passed up from the driver (including host and
* driver components)
*
* This returns true for known good conditions that may be treated as
* command completed normally
*/
static inline int scsi_status_is_good(int status)
{
if (host_byte(status) == DID_NO_CONNECT)
return 0;
/*
* FIXME: bit0 is listed as reserved in SCSI-2, but is
* significant in SCSI-3. For now, we follow the SCSI-2
* behaviour and ignore reserved bits.
*/
status &= 0xfe;
return ((status == SAM_STAT_GOOD) ||
(status == SAM_STAT_CONDITION_MET) ||
/* Next two "intermediate" statuses are obsolete in SAM-4 */
(status == SAM_STAT_INTERMEDIATE) ||
(status == SAM_STAT_INTERMEDIATE_CONDITION_MET) ||
/* FIXME: this is obsolete in SAM-3 */
(status == SAM_STAT_COMMAND_TERMINATED));
}
#endif /* _SCSI_SCSI_H */