ocfs2: take inode cluster lock before moving reflinked inode from orphan dir
authorAshish Samant <ashish.samant@oracle.com>
Fri, 11 May 2018 23:02:07 +0000 (16:02 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 20 Jun 2018 19:02:57 +0000 (04:02 +0900)
commit12ddc2639e31d96f5b136a84baf7d2b312db5519
tree39a4bede1bf23c2b7439e7a83233ae92e8e3f4e5
parent553495752c8241ef0a4a2c2fc3a5c8298899ec81
ocfs2: take inode cluster lock before moving reflinked inode from orphan dir

[ Upstream commit e4383029201470523c3ffe339bd7d57e9b4a7d65 ]

While reflinking an inode, we create a new inode in orphan directory,
then take EX lock on it, reflink the original inode to orphan inode and
release EX lock.  Once the lock is released another node could request
it in EX mode from ocfs2_recover_orphans() which causes downconvert of
the lock, on this node, to NL mode.

Later we attempt to initialize security acl for the orphan inode and
move it to the reflink destination.  However, while doing this we dont
take EX lock on the inode.  This could potentially cause problems
because we could be starting transaction, accessing journal and
modifying metadata of the inode while holding NL lock and with another
node holding EX lock on the inode.

Fix this by taking orphan inode cluster lock in EX mode before
initializing security and moving orphan inode to reflink destination.
Use the __tracker variant while taking inode lock to avoid recursive
locking in the ocfs2_init_security_and_acl() call chain.

Link: http://lkml.kernel.org/r/1523475107-7639-1-git-send-email-ashish.samant@oracle.com
Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Acked-by: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/ocfs2/refcounttree.c