target: Add workaround for zero-length control CDB handling
This patch adds a work-around for handling zero allocation length
control CDBs (type SCF_SCSI_CONTROL_SG_IO_CDB) that was causing an
OOPs with the following raw calls:
# sg_raw -v /dev/sdd 3 0 0 0 0 0
# sg_raw -v /dev/sdd 0x1a 0 1 0 0 0
This patch will follow existing zero-length handling for data I/O
and silently return with GOOD status. This addresses the zero length
issue, but the proper long-term resolution for handling arbitary
allocation lengths will be to refactor out data-phase handling in
individual CDB emulation logic within target_core_cdb.c
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 2869fb7..50d6911 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -3759,6 +3759,11 @@
struct se_task *task;
unsigned long flags;
+ /* Workaround for handling zero-length control CDBs */
+ if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
+ !cmd->data_length)
+ return 0;
+
task = transport_generic_get_task(cmd, cmd->data_direction);
if (!task)
return -ENOMEM;
@@ -3830,6 +3835,14 @@
else if (!task_cdbs && (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)) {
cmd->t_state = TRANSPORT_COMPLETE;
atomic_set(&cmd->t_transport_active, 1);
+
+ if (cmd->t_task_cdb[0] == REQUEST_SENSE) {
+ u8 ua_asc = 0, ua_ascq = 0;
+
+ core_scsi3_ua_clear_for_request_sense(cmd,
+ &ua_asc, &ua_ascq);
+ }
+
INIT_WORK(&cmd->work, target_complete_ok_work);
queue_work(target_completion_wq, &cmd->work);
return 0;
