+ ocfs2-add-journal-null-check-in-ocfs2_checkpoint_inode.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: ocfs2: add journal NULL check in ocfs2_checkpoint_inode()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     ocfs2-add-journal-null-check-in-ocfs2_checkpoint_inode.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ocfs2-add-journal-null-check-in-ocfs2_checkpoint_inode.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Joseph Qi <joseph.qi@linux.alibaba.com>
Subject: ocfs2: add journal NULL check in ocfs2_checkpoint_inode()
Date: Sun, 31 May 2026 21:16:45 +0800

During unmount, ocfs2_journal_shutdown() frees the journal and sets
osb->journal to NULL. Later, when VFS evicts remaining cached inodes,
ocfs2_evict_inode() -> ocfs2_clear_inode() -> ocfs2_checkpoint_inode()
-> ocfs2_ci_fully_checkpointed() dereferences osb->journal, causing a
NULL pointer dereference.

Fix this by adding a NULL check for osb->journal in
ocfs2_checkpoint_inode(). If the journal is NULL, it has already been
fully flushed and destroyed during shutdown, so there is nothing to
checkpoint.

Link: https://lore.kernel.org/20260531131645.3650299-1-joseph.qi@linux.alibaba.com
Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Fixes: da5e7c87827e ("ocfs2: cleanup journal init and shutdown")
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Tested-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/ocfs2/journal.h |    3 +++
 1 file changed, 3 insertions(+)

--- a/fs/ocfs2/journal.h~ocfs2-add-journal-null-check-in-ocfs2_checkpoint_inode
+++ a/fs/ocfs2/journal.h
@@ -196,6 +196,9 @@ static inline void ocfs2_checkpoint_inod
 	if (ocfs2_mount_local(osb))
 		return;
 
+	if (!osb->journal)
+		return;
+
 	if (!ocfs2_ci_fully_checkpointed(INODE_CACHE(inode))) {
 		/* WARNING: This only kicks off a single
 		 * checkpoint. If someone races you and adds more
_

Patches currently in -mm which might be from joseph.qi@linux.alibaba.com are

ocfs2-add-journal-null-check-in-ocfs2_checkpoint_inode.patch