ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang

commit 5ee0fbd50fdf1c1329de8bee35ea9d7c6a81a2e0 upstream.

Commit 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
introduced this issue.  ocfs2_setattr called by chmod command holds
cluster wide inode lock when calling posix_acl_chmod.  This latter
function in turn calls ocfs2_iop_get_acl and ocfs2_iop_set_acl.  These
two are also called directly from vfs layer for getfacl/setfacl commands
and therefore acquire the cluster wide inode lock.  If a remote
conversion request comes after the first inode lock in ocfs2_setattr,
OCFS2_LOCK_BLOCKED will be set.  And this will cause the second call to
inode lock from the ocfs2_iop_get_acl() to block indefinetly.

The deleted version of ocfs2_acl_chmod() calls __posix_acl_chmod() which
does not call back into the filesystem.  Therefore, we restore
ocfs2_acl_chmod(), modify it slightly for locking as needed, and use that
instead.

Fixes: 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 0cdf497c91efbb915512aceed2bf58acaa37fa1d..749d3bc41232f6c482aaad12bb12be0bf4935f12 100644 (file)
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -322,3 +322,27 @@ struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type)
        brelse(di_bh);
        return acl;
 }
+
+int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh)
+{
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       struct posix_acl *acl;
+       int ret;
+
+       if (S_ISLNK(inode->i_mode))
+               return -EOPNOTSUPP;
+
+       if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
+               return 0;
+
+       acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh);
+       if (IS_ERR(acl) || !acl)
+               return PTR_ERR(acl);
+       ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
+       if (ret)
+               return ret;
+       ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS,
+                           acl, NULL, NULL);
+       posix_acl_release(acl);
+       return ret;
+}

diff --git a/fs/ocfs2/acl.h b/fs/ocfs2/acl.h
index 3fce68d086251a6e26ea9805361e3a1ccb351d46..035e5878db0675c7dfcd5b4c449abf7727f9e9bf 100644 (file)
--- a/fs/ocfs2/acl.h
+++ b/fs/ocfs2/acl.h
@@ -35,5 +35,6 @@ int ocfs2_set_acl(handle_t *handle,
                         struct posix_acl *acl,
                         struct ocfs2_alloc_context *meta_ac,
                         struct ocfs2_alloc_context *data_ac);
+extern int ocfs2_acl_chmod(struct inode *, struct buffer_head *);
 
 #endif /* OCFS2_ACL_H */

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 0e5b4515f92e7a875a6f396db0d5648c9c157ad1..77d30cbd944d7c7d834456469677032fdb3d55a1 100644 (file)
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1268,20 +1268,20 @@ bail_unlock_rw:
        if (size_change)
                ocfs2_rw_unlock(inode, 1);
 bail:
-       brelse(bh);
 
        /* Release quota pointers in case we acquired them */
        for (qtype = 0; qtype < OCFS2_MAXQUOTAS; qtype++)
                dqput(transfer_to[qtype]);
 
        if (!status && attr->ia_valid & ATTR_MODE) {
-               status = posix_acl_chmod(inode, inode->i_mode);
+               status = ocfs2_acl_chmod(inode, bh);
                if (status < 0)
                        mlog_errno(status);
        }
        if (inode_locked)
                ocfs2_inode_unlock(inode, 1);
 
+       brelse(bh);
        return status;
 }