[PATCH 3.18 20/20] target/iscsi: Fix iSCSI task reassignment handling

From: Greg Kroah-Hartman
Date: Thu Nov 16 2017 - 12:31:15 EST


3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>

commit 59b6986dbfcdab96a971f9663221849de79a7556 upstream.

Allocate a task management request structure for all task management
requests, including task reassignment. This change avoids that the
se_tmr->response assignment dereferences an uninitialized se_tmr
pointer.

Reported-by: Moshe David <mdavid@xxxxxxxxxxxxx>
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Moshe David <mdavid@xxxxxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
drivers/target/iscsi/iscsi_target.c | 19 +++++++------------
include/target/target_core_base.h | 1 +
2 files changed, 8 insertions(+), 12 deletions(-)

--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -1749,7 +1749,7 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
struct iscsi_tm *hdr;
int out_of_order_cmdsn = 0, ret;
bool sess_ref = false;
- u8 function;
+ u8 function, tcm_function = TMR_UNKNOWN;

hdr = (struct iscsi_tm *) buf;
hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
@@ -1795,10 +1795,6 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
* LIO-Target $FABRIC_MOD
*/
if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
-
- u8 tcm_function;
- int ret;
-
transport_init_se_cmd(&cmd->se_cmd,
&lio_target_fabric_configfs->tf_ops,
conn->sess->se_sess, 0, DMA_NONE,
@@ -1835,15 +1831,14 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
return iscsit_add_reject_cmd(cmd,
ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
}
-
- ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
- tcm_function, GFP_KERNEL);
- if (ret < 0)
- return iscsit_add_reject_cmd(cmd,
+ }
+ ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
+ GFP_KERNEL);
+ if (ret < 0)
+ return iscsit_add_reject_cmd(cmd,
ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);

- cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
- }
+ cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;

cmd->iscsi_opcode = ISCSI_OP_SCSI_TMFUNC;
cmd->i_state = ISTATE_SEND_TASKMGTRSP;
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -231,6 +231,7 @@ enum tcm_tmreq_table {
TMR_LUN_RESET = 5,
TMR_TARGET_WARM_RESET = 6,
TMR_TARGET_COLD_RESET = 7,
+ TMR_UNKNOWN = 0xff,
};

/* fabric independent task management response values */