scsi: target/iscsi: Make sure PDU processing continues if parsing a command fails

Currently the iSCSI target driver sends a CHECK CONDITION code back to the
initiator if the immediate data buffer is too large but it does not discard
that immediate data buffer. The result is that the iSCSI target driver
attempts to parse the immediate data itself as iSCSI PDUs and that all
further iSCSI communication fails. Fix this by receiving and discarding too
large immediate data buffers.

Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Bart Van Assche 2019-04-02 12:58:15 -07:00 committed by Martin K. Petersen
parent 2e39f1c906
commit 4b3766ec0e
1 changed files with 18 additions and 21 deletions

View File

@ -1285,27 +1285,27 @@ iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
bool dump_payload) bool dump_payload)
{ {
int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION; int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
int rc;
/* /*
* Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes. * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
*/ */
if (dump_payload) if (dump_payload) {
goto after_immediate_data; u32 length = min(cmd->se_cmd.data_length - cmd->write_data_done,
/* cmd->first_burst_len);
* Check for underflow case where both EDTL and immediate data payload
* exceeds what is presented by CDB's TRANSFER LENGTH, and what has pr_debug("Dumping min(%d - %d, %d) = %d bytes of immediate data\n",
* already been set in target_cmd_size_check() as se_cmd->data_length. cmd->se_cmd.data_length, cmd->write_data_done,
* cmd->first_burst_len, length);
* For this special case, fail the command and dump the immediate data rc = iscsit_dump_data_payload(cmd->conn, length, 1);
* payload. pr_debug("Finished dumping immediate data\n");
*/ if (rc < 0)
if (cmd->first_burst_len > cmd->se_cmd.data_length) { immed_ret = IMMEDIATE_DATA_CANNOT_RECOVER;
cmd->sense_reason = TCM_INVALID_CDB_FIELD; } else {
goto after_immediate_data; immed_ret = iscsit_handle_immediate_data(cmd, hdr,
cmd->first_burst_len);
} }
immed_ret = iscsit_handle_immediate_data(cmd, hdr,
cmd->first_burst_len);
after_immediate_data:
if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) { if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
/* /*
* A PDU/CmdSN carrying Immediate Data passed * A PDU/CmdSN carrying Immediate Data passed
@ -1318,12 +1318,9 @@ after_immediate_data:
return -1; return -1;
if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) { if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
int rc;
rc = iscsit_dump_data_payload(cmd->conn,
cmd->first_burst_len, 1);
target_put_sess_cmd(&cmd->se_cmd); target_put_sess_cmd(&cmd->se_cmd);
return rc;
return 0;
} else if (cmd->unsolicited_data) } else if (cmd->unsolicited_data)
iscsit_set_unsolicited_dataout(cmd); iscsit_set_unsolicited_dataout(cmd);