4.4-stable review patch. If anyone has any objections, please let me know.
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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 | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-)
--- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -1759,7 +1759,6 @@ 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; @@ -1801,18 +1800,17 @@ iscsit_handle_task_mgt_cmd(struct iscsi_ buf); }
+ transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops, + conn->sess->se_sess, 0, DMA_NONE, + TCM_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, &iscsi_ops, - conn->sess->se_sess, 0, DMA_NONE, - TCM_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; @@ -1951,12 +1949,8 @@ 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);