[PATCH AUTOSEL 4.19 26/38] scsi: target: core: Do not overwrite CDB byte 1

Sasha Levin
2019-10-30T16:00:38Z

From: Bodo Stroesser <bstroesser@ts.fujitsu.com>

[ Upstream commit 27e84243cb63601a10e366afe3e2d05bb03c1cb5 ]

passthrough_parse_cdb() - used by TCMU and PSCSI - attepts to reset the LUN
field of SCSI-2 CDBs (bits 5,6,7 of byte 1). The current code is wrong as
for newer commands not having the LUN field it overwrites relevant command
bits (e.g. for SECURITY PROTOCOL IN / OUT). We think this code was
unnecessary from the beginning or at least it is no longer useful. So we
remove it entirely.

Link: https://lore.kernel.org/r/12498eab-76fd-eaad-1316-c2827badb76a@ts.fujitsu.com
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/target/target_core_device.c | 21 ---------------------
1 file changed, 21 deletions(-)

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 47b5ef153135c..e9ff2a7c0c0e6 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -1128,27 +1128,6 @@ passthrough_parse_cdb(struct se_cmd *cmd,
struct se_device *dev = cmd->se_dev;
unsigned int size;

- /*
- * Clear a lun set in the cdb if the initiator talking to use spoke
- * and old standards version, as we can't assume the underlying device
- * won't choke up on it.
- */
- switch (cdb[0]) {
- case READ_10: /* SBC - RDProtect */
- case READ_12: /* SBC - RDProtect */
- case READ_16: /* SBC - RDProtect */
- case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
- case VERIFY: /* SBC - VRProtect */
- case VERIFY_16: /* SBC - VRProtect */
- case WRITE_VERIFY: /* SBC - VRProtect */
- case WRITE_VERIFY_12: /* SBC - VRProtect */
- case MAINTENANCE_IN: /* SPC - Parameter Data Format for SA RTPG */
- break;
- default:
- cdb[1] &= 0x1f; /* clear logical unit number */
- break;
- }
-
/*
* For REPORT LUNS we always need to emulate the response, for everything
* else, pass it up.
--
2.20.1