From: Jiang Yi <jiangyilism@gmail.com>
Date: Fri, 2 Jun 2017 11:45:09 +0800
Subject: target: reject COMPARE_AND_WRITE if emulate_caw is not set
Git-commit: 12f66e4a0f7b5624901ba4301210e026c9ddf78d
Patch-mainline: v4.13-rc1
References: fate#323946
In struct se_dev_attrib, there is a field emulate_caw exposed
as a /sys/kernel/config/target/core/$HBA/$DEV/attrib/.
If this field is set zero, it means the corresponding struct se_device
does not support the scsi cmd COMPARE_AND_WRITE
In function sbc_parse_cdb(), go ahead and reject scsi COMPARE_AND_WRITE
if emulate_caw is not set, because it has been explicitly disabled
from user-space.
(Make pr_err ratelimited - nab)
Signed-off-by: Jiang Yi <jiangyilism@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Acked-by: Lee Duncan <lduncan@suse.com>
---
drivers/target/target_core_sbc.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 4316f7b65fb7..ff4a6ec30adf 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -1005,6 +1005,12 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool succes
break;
}
case COMPARE_AND_WRITE:
+ if (!dev->dev_attrib.emulate_caw) {
+ pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject"
+ " COMPARE_AND_WRITE\n", dev->se_hba->backend->ops->name,
+ dev->dev_group.cg_item.ci_name, dev->t10_wwn.unit_serial);
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
+ }
sectors = cdb[13];
/*
* Currently enforce COMPARE_AND_WRITE for a single sector