scsi: target: Fix protect handling in WRITE SAME(32)

WRITE SAME(32) command handling reads WRPROTECT at the wrong offset in 1st
byte instead of 10th byte.

Link: https://lore.kernel.org/r/20210702091655.22818-1-d.bogdanov@yadro.com
Fixes: afd73f1b ("target: Perform PROTECT sanity checks for WRITE_SAME")
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/target/target_core_sbc.c

@@ -25,7 +25,7 @@
 #include "target_core_alua.h"
 
 static sense_reason_t
-sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
+sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char, u32, bool);
 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
 
 static sense_reason_t
@@ -279,14 +279,14 @@ static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 }
 
 static sense_reason_t
-sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
+sbc_setup_write_same(struct se_cmd *cmd, unsigned char flags, struct sbc_ops *ops)
 {
 	struct se_device *dev = cmd->se_dev;
 	sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 	unsigned int sectors = sbc_get_write_same_sectors(cmd);
 	sense_reason_t ret;
 
-	if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
+	if ((flags & 0x04) || (flags & 0x02)) {
 		pr_err("WRITE_SAME PBDATA and LBDATA"
 			" bits not supported for Block Discard"
 			" Emulation\n");
@@ -308,7 +308,7 @@ sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *o
 	}
 
 	/* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
-	if (flags[0] & 0x10) {
+	if (flags & 0x10) {
 		pr_warn("WRITE SAME with ANCHOR not supported\n");
 		return TCM_INVALID_CDB_FIELD;
 	}
@@ -316,7 +316,7 @@ sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *o
 	 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 	 * translated into block discard requests within backend code.
 	 */
-	if (flags[0] & 0x08) {
+	if (flags & 0x08) {
 		if (!ops->execute_unmap)
 			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
@@ -331,7 +331,7 @@ sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *o
 	if (!ops->execute_write_same)
 		return TCM_UNSUPPORTED_SCSI_OPCODE;
 
-	ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
+	ret = sbc_check_prot(dev, cmd, flags >> 5, sectors, true);
 	if (ret)
 		return ret;
 
@@ -717,10 +717,9 @@ sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_
 }
 
 static sense_reason_t
-sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
+sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect,
 	       u32 sectors, bool is_write)
 {
-	u8 protect = cdb[1] >> 5;
 	int sp_ops = cmd->se_sess->sup_prot_ops;
 	int pi_prot_type = dev->dev_attrib.pi_prot_type;
 	bool fabric_prot = false;
@@ -768,7 +767,7 @@ sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 		fallthrough;
 	default:
 		pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
-		       "PROTECT: 0x%02x\n", cdb[0], protect);
+		       "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect);
 		return TCM_INVALID_CDB_FIELD;
 	}
 
@@ -843,7 +842,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 		if (ret)
 			return ret;
 
@@ -857,7 +856,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 		if (ret)
 			return ret;
 
@@ -871,7 +870,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 		if (ret)
 			return ret;
 
@@ -892,7 +891,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 		if (ret)
 			return ret;
 
@@ -906,7 +905,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 		if (ret)
 			return ret;
 
@@ -921,7 +920,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		if (sbc_check_dpofua(dev, cmd, cdb))
 			return TCM_INVALID_CDB_FIELD;
 
-		ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
+		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 		if (ret)
 			return ret;
 
@@ -980,7 +979,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 			size = sbc_get_size(cmd, 1);
 			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 
-			ret = sbc_setup_write_same(cmd, &cdb[10], ops);
+			ret = sbc_setup_write_same(cmd, cdb[10], ops);
 			if (ret)
 				return ret;
 			break;
@@ -1079,7 +1078,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		size = sbc_get_size(cmd, 1);
 		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 
-		ret = sbc_setup_write_same(cmd, &cdb[1], ops);
+		ret = sbc_setup_write_same(cmd, cdb[1], ops);
 		if (ret)
 			return ret;
 		break;
@@ -1097,7 +1096,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
 		 * of byte 1 bit 3 UNMAP instead of original reserved field
 		 */
-		ret = sbc_setup_write_same(cmd, &cdb[1], ops);
+		ret = sbc_setup_write_same(cmd, cdb[1], ops);
 		if (ret)
 			return ret;
 		break;