This is a note to let you know that I've just added the patch titled

iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref

to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From ae072726f6109bb1c94841d6fb3a82dde298ea85 Mon Sep 17 00:00:00 2001

From: Nicholas Bellinger nab@linux-iscsi.org Date: Fri, 27 Oct 2017 12:32:59 -0700 Subject: iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref

From: Nicholas Bellinger nab@linux-iscsi.org

commit ae072726f6109bb1c94841d6fb3a82dde298ea85 upstream.

Since commit 59b6986dbf fixed a potential NULL pointer dereference by allocating a se_tmr_req for ISCSI_TM_FUNC_TASK_REASSIGN, the se_tmr_req is currently leaked by iscsit_free_cmd() because no iscsi_cmd->se_cmd.se_tfo was associated.

To address this, treat ISCSI_TM_FUNC_TASK_REASSIGN like any other TMR and call transport_init_se_cmd() + target_get_sess_cmd() to setup iscsi_cmd->se_cmd.se_tfo with se_cmd->cmd_kref of 2.

This will ensure normal release operation once se_cmd->cmd_kref reaches zero and target_release_cmd_kref() is invoked, se_tmr_req will be released via existing target_free_cmd_mem() and core_tmr_release_req() code.

Reported-by: Donald White dew@datera.io Cc: Donald White dew@datera.io Cc: Mike Christie mchristi@redhat.com Cc: Hannes Reinecke hare@suse.com Signed-off-by: Nicholas Bellinger nab@linux-iscsi.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/target/iscsi/iscsi_target.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-)

--- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -1750,7 +1750,6 @@ iscsit_handle_task_mgt_cmd(struct iscsi_ struct iscsi_tmr_req *tmr_req; struct iscsi_tm *hdr; int out_of_order_cmdsn = 0, ret; - bool sess_ref = false; u8 function, tcm_function = TMR_UNKNOWN;

hdr = (struct iscsi_tm *) buf; @@ -1792,19 +1791,17 @@ iscsit_handle_task_mgt_cmd(struct iscsi_ buf); }

+ transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops, + conn->sess->se_sess, 0, DMA_NONE, + MSG_SIMPLE_TAG, cmd->sense_buffer + 2); + + target_get_sess_cmd(&cmd->se_cmd, true); + /* * TASK_REASSIGN for ERL=2 / connection stays inside of * LIO-Target $FABRIC_MOD */ if (function != ISCSI_TM_FUNC_TASK_REASSIGN) { - transport_init_se_cmd(&cmd->se_cmd, - &lio_target_fabric_configfs->tf_ops, - conn->sess->se_sess, 0, DMA_NONE, - MSG_SIMPLE_TAG, cmd->sense_buffer + 2); - - target_get_sess_cmd(&cmd->se_cmd, true); - sess_ref = true; - switch (function) { case ISCSI_TM_FUNC_ABORT_TASK: tcm_function = TMR_ABORT_TASK; @@ -1943,12 +1940,8 @@ attach: * For connection recovery, this is also the default action for * TMR TASK_REASSIGN. */ - if (sess_ref) { - pr_debug("Handle TMR, using sess_ref=true check\n"); - target_put_sess_cmd(&cmd->se_cmd); - } - iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + target_put_sess_cmd(&cmd->se_cmd); return 0; } EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);

Patches currently in stable-queue which might be from nab@linux-iscsi.org are

queue-3.18/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch queue-3.18/target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch