lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20191006171129.936624789@linuxfoundation.org>
Date:   Sun,  6 Oct 2019 19:21:22 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Changwei Ge <gechangwei@...e.cn>,
        Joseph Qi <joseph.qi@...ux.alibaba.com>,
        Mark Fasheh <mark@...heh.com>,
        Joel Becker <jlbec@...lplan.org>,
        Junxiao Bi <junxiao.bi@...cle.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.14 46/68] ocfs2: wait for recovering done after direct unlock request

From: Changwei Ge <gechangwei@...e.cn>

[ Upstream commit 0a3775e4f883912944481cf2ef36eb6383a9cc74 ]

There is a scenario causing ocfs2 umount hang when multiple hosts are
rebooting at the same time.

NODE1                           NODE2               NODE3
send unlock requset to NODE2
                                dies
                                                    become recovery master
                                                    recover NODE2
find NODE2 dead
mark resource RECOVERING
directly remove lock from grant list
calculate usage but RECOVERING marked
**miss the window of purging
clear RECOVERING

To reproduce this issue, crash a host and then umount ocfs2
from another node.

To solve this, just let unlock progress wait for recovery done.

Link: http://lkml.kernel.org/r/1550124866-20367-1-git-send-email-gechangwei@live.cn
Signed-off-by: Changwei Ge <gechangwei@...e.cn>
Reviewed-by: Joseph Qi <joseph.qi@...ux.alibaba.com>
Cc: Mark Fasheh <mark@...heh.com>
Cc: Joel Becker <jlbec@...lplan.org>
Cc: Junxiao Bi <junxiao.bi@...cle.com>
Cc: Changwei Ge <gechangwei@...e.cn>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/ocfs2/dlm/dlmunlock.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/fs/ocfs2/dlm/dlmunlock.c b/fs/ocfs2/dlm/dlmunlock.c
index 63d701cd1e2e7..c8e9b7031d9ad 100644
--- a/fs/ocfs2/dlm/dlmunlock.c
+++ b/fs/ocfs2/dlm/dlmunlock.c
@@ -105,7 +105,8 @@ static enum dlm_status dlmunlock_common(struct dlm_ctxt *dlm,
 	enum dlm_status status;
 	int actions = 0;
 	int in_use;
-        u8 owner;
+	u8 owner;
+	int recovery_wait = 0;
 
 	mlog(0, "master_node = %d, valblk = %d\n", master_node,
 	     flags & LKM_VALBLK);
@@ -208,9 +209,12 @@ static enum dlm_status dlmunlock_common(struct dlm_ctxt *dlm,
 		}
 		if (flags & LKM_CANCEL)
 			lock->cancel_pending = 0;
-		else
-			lock->unlock_pending = 0;
-
+		else {
+			if (!lock->unlock_pending)
+				recovery_wait = 1;
+			else
+				lock->unlock_pending = 0;
+		}
 	}
 
 	/* get an extra ref on lock.  if we are just switching
@@ -244,6 +248,17 @@ leave:
 	spin_unlock(&res->spinlock);
 	wake_up(&res->wq);
 
+	if (recovery_wait) {
+		spin_lock(&res->spinlock);
+		/* Unlock request will directly succeed after owner dies,
+		 * and the lock is already removed from grant list. We have to
+		 * wait for RECOVERING done or we miss the chance to purge it
+		 * since the removement is much faster than RECOVERING proc.
+		 */
+		__dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_RECOVERING);
+		spin_unlock(&res->spinlock);
+	}
+
 	/* let the caller's final dlm_lock_put handle the actual kfree */
 	if (actions & DLM_UNLOCK_FREE_LOCK) {
 		/* this should always be coupled with list removal */
-- 
2.20.1



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ