lkml.org 
[lkml]   [2014]   [Jul]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.8 115/116] iscsi-target: Fix incorrect np->np_thread NULL assignment
Date
3.8.13.27 -stable review patch.  If anyone has any objections, please let me know.

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

From: Nicholas Bellinger <nab@linux-iscsi.org>

commit db6077fd0b7dd41dc6ff18329cec979379071f87 upstream.

When shutting down a target there is a race condition between
iscsit_del_np() and __iscsi_target_login_thread().
The latter sets the thread pointer to NULL, and the former
tries to issue kthread_stop() on that pointer without any
synchronization.

This patch moves the np->np_thread NULL assignment into
iscsit_del_np(), after kthread_stop() has completed. It also
removes the signal_pending() + np_state check, and only
exits when kthread_should_stop() is true.

Reported-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/target/iscsi/iscsi_target.c | 1 +
drivers/target/iscsi/iscsi_target_login.c | 5 -----
2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
index a6326f1..ba56bfe 100644
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -460,6 +460,7 @@ int iscsit_del_np(struct iscsi_np *np)
*/
send_sig(SIGINT, np->np_thread, 1);
kthread_stop(np->np_thread);
+ np->np_thread = NULL;
}
iscsit_del_np_comm(np);

diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index fdb632f..6b82c62 100644
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -1167,11 +1167,6 @@ old_sess_out:

out:
stop = kthread_should_stop();
- if (!stop && signal_pending(current)) {
- spin_lock_bh(&np->np_thread_lock);
- stop = (np->np_thread_state == ISCSI_NP_THREAD_SHUTDOWN);
- spin_unlock_bh(&np->np_thread_lock);
- }
/* Wait for another socket.. */
if (!stop)
return 1;
--
1.9.1


\
 
 \ /
  Last update: 2014-07-23 01:41    [W:0.998 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site