iscsi-target: Fix iscsit_sequence_cmd reject handling for iser

This patch moves ISCSI_OP_REJECT failures into iscsit_sequence_cmd()
in order to avoid external iscsit_reject_cmd() reject usage for all
PDU types.

It also updates PDU specific handlers for traditional iscsi-target
code to not reset the session after posting a ISCSI_OP_REJECT during
setup.

(v2: Fix CMDSN_LOWER_THAN_EXP for ISCSI_OP_SCSI to call
     target_put_sess_cmd() after iscsit_sequence_cmd() failure)

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@vger.kernel.org  # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

4 files changed, 59 insertions, 31 deletions

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index 2a25bd3..4319dad 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -1052,11 +1052,11 @@ int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 	 * be acknowledged. (See below)
 	 */
 	if (!cmd->immediate_data) {
-		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
-		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
-			if (!cmd->sense_reason)
-				return 0;
-
+		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
+					(unsigned char *)hdr, hdr->cmdsn);
+		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
+			return -1;
+		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
 			return 0;
 		}
@@ -1083,6 +1083,9 @@ int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
 	 */
 	if (cmd->sense_reason) {
+		if (cmd->reject_reason)
+			return 0;
+
 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
 		return 1;
 	}
@@ -1091,10 +1094,8 @@ int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 	 * the backend memory allocation.
 	 */
 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
-	if (cmd->sense_reason) {
-		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
+	if (cmd->sense_reason)
 		return 1;
-	}
 
 	return 0;
 }
@@ -1104,6 +1105,7 @@ static int
 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
 			  bool dump_payload)
 {
+	struct iscsi_conn *conn = cmd->conn;
 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
 	/*
 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
@@ -1120,12 +1122,22 @@ after_immediate_data:
 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
 		 * Immediate Bit is not set.
 		 */
-		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd, hdr->cmdsn);
+		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
+					(unsigned char *)hdr, hdr->cmdsn);
+		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
+			return -1;
+		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
+			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
+			return 0;
+		}
 
 		if (cmd->sense_reason) {
-			if (iscsit_dump_data_payload(cmd->conn,
-					cmd->first_burst_len, 1) < 0)
-				return -1;
+			int rc;
+
+			rc = iscsit_dump_data_payload(cmd->conn,
+						      cmd->first_burst_len, 1);
+			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
+			return rc;
 		} else if (cmd->unsolicited_data)
 			iscsit_set_unsoliticed_dataout(cmd);
 
@@ -1159,7 +1171,7 @@ iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 
 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
 	if (rc < 0)
-		return rc;
+		return 0;
 	/*
 	 * Allocation iovecs needed for struct socket operations for
 	 * traditional iSCSI block I/O.
@@ -1494,7 +1506,7 @@ static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
 
 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
 	if (rc < 0)
-		return rc;
+		return 0;
 	else if (!cmd)
 		return 0;
 
@@ -1579,10 +1591,10 @@ int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 			return 0;
 		}
 
-		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
+		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
+				(unsigned char *)hdr, hdr->cmdsn);
                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
 			return 0;
-
 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
 			return -1;
 
@@ -1623,7 +1635,7 @@ static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 
 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
 	if (ret < 0)
-		return ret;
+		return 0;
 	/*
 	 * Handle NOP-OUT payload for traditional iSCSI sockets
 	 */
@@ -1893,7 +1905,7 @@ attach:
 	spin_unlock_bh(&conn->cmd_lock);
 
 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
-		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
+		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
 			out_of_order_cmdsn = 1;
 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
@@ -1996,7 +2008,8 @@ iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
 
 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
-		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
+		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
+				(unsigned char *)hdr, hdr->cmdsn);
 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
 			return -1;
 
@@ -2022,7 +2035,7 @@ iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 
 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
 	if (rc < 0)
-		return rc;
+		return 0;
 
 	rx_size = payload_length;
 	if (payload_length) {
@@ -2284,7 +2297,7 @@ iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 		if (ret < 0)
 			return ret;
 	} else {
-		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
+		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
 			logout_remove = 0;
 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
diff --git a/drivers/target/iscsi/iscsi_target_erl1.c b/drivers/target/iscsi/iscsi_target_erl1.c
index d00f132..586c268 100644
--- a/drivers/target/iscsi/iscsi_target_erl1.c
+++ b/drivers/target/iscsi/iscsi_target_erl1.c
@@ -1088,7 +1088,7 @@ int iscsit_handle_ooo_cmdsn(
 
 	ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
 	if (!ooo_cmdsn)
-		return CMDSN_ERROR_CANNOT_RECOVER;
+		return -ENOMEM;
 
 	ooo_cmdsn->cmd			= cmd;
 	ooo_cmdsn->batch_count		= (batch) ?
@@ -1099,10 +1099,10 @@ int iscsit_handle_ooo_cmdsn(
 
 	if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
 		kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
-		return CMDSN_ERROR_CANNOT_RECOVER;
+		return -ENOMEM;
 	}
 
-	return CMDSN_HIGHER_THAN_EXP;
+	return 0;
 }
 
 static int iscsit_set_dataout_timeout_values(
diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c
index 96ce6f2..1df06d5 100644
--- a/drivers/target/iscsi/iscsi_target_util.c
+++ b/drivers/target/iscsi/iscsi_target_util.c
@@ -283,13 +283,12 @@ static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cm
  * Commands may be received out of order if MC/S is in use.
  * Ensure they are executed in CmdSN order.
  */
-int iscsit_sequence_cmd(
-	struct iscsi_conn *conn,
-	struct iscsi_cmd *cmd,
-	__be32 cmdsn)
+int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
+			unsigned char *buf, __be32 cmdsn)
 {
-	int ret;
-	int cmdsn_ret;
+	int ret, cmdsn_ret;
+	bool reject = false;
+	u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
 
 	mutex_lock(&conn->sess->cmdsn_mutex);
 
@@ -299,9 +298,19 @@ int iscsit_sequence_cmd(
 		ret = iscsit_execute_cmd(cmd, 0);
 		if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
 			iscsit_execute_ooo_cmdsns(conn->sess);
+		else if (ret < 0) {
+			reject = true;
+			ret = CMDSN_ERROR_CANNOT_RECOVER;
+		}
 		break;
 	case CMDSN_HIGHER_THAN_EXP:
 		ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
+		if (ret < 0) {
+			reject = true;
+			ret = CMDSN_ERROR_CANNOT_RECOVER;
+			break;
+		}
+		ret = CMDSN_HIGHER_THAN_EXP;
 		break;
 	case CMDSN_LOWER_THAN_EXP:
 		cmd->i_state = ISTATE_REMOVE;
@@ -309,11 +318,16 @@ int iscsit_sequence_cmd(
 		ret = cmdsn_ret;
 		break;
 	default:
+		reason = ISCSI_REASON_PROTOCOL_ERROR;
+		reject = true;
 		ret = cmdsn_ret;
 		break;
 	}
 	mutex_unlock(&conn->sess->cmdsn_mutex);
 
+	if (reject)
+		iscsit_reject_cmd(cmd, reason, buf);
+
 	return ret;
 }
 EXPORT_SYMBOL(iscsit_sequence_cmd);
diff --git a/drivers/target/iscsi/iscsi_target_util.h b/drivers/target/iscsi/iscsi_target_util.h
index a442265..e4fc34a 100644
--- a/drivers/target/iscsi/iscsi_target_util.h
+++ b/drivers/target/iscsi/iscsi_target_util.h
@@ -13,7 +13,8 @@ extern struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *, gfp_t);
 extern struct iscsi_seq *iscsit_get_seq_holder_for_datain(struct iscsi_cmd *, u32);
 extern struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *);
 extern struct iscsi_r2t *iscsit_get_holder_for_r2tsn(struct iscsi_cmd *, u32);
-int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd, __be32 cmdsn);
+extern int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
+			       unsigned char * ,__be32 cmdsn);
 extern int iscsit_check_unsolicited_dataout(struct iscsi_cmd *, unsigned char *);
 extern struct iscsi_cmd *iscsit_find_cmd_from_itt(struct iscsi_conn *, itt_t);
 extern struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(struct iscsi_conn *,