ocfs2: quota_local: fix possible uninitialized-variable access in ocfs2_local_read_info()

A memory block is allocated through kmalloc(), and its return value is
assigned to the pointer oinfo. However, oinfo->dqi_gqinode is not
initialized but it is accessed in:
  iput(oinfo->dqi_gqinode);

To fix this possible uninitialized-variable access, assign NULL to
oinfo->dqi_gqinode, and add ocfs2_qinfo_lock_res_init() behind the
assignment in ocfs2_local_read_info().  Remove ocfs2_qinfo_lock_res_init()
in ocfs2_global_read_info().

Link: https://lkml.kernel.org/r/20210804031832.57154-1-islituo@gmail.com
Signed-off-by: Tuo Li <islituo@gmail.com>
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
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: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/quota_global.c

@@ -357,7 +357,6 @@ int ocfs2_global_read_info(struct super_block *sb, int type)
 	}
 	oinfo->dqi_gi.dqi_sb = sb;
 	oinfo->dqi_gi.dqi_type = type;
-	ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
 	oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk);
 	oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops;
 	oinfo->dqi_gqi_bh = NULL;

fs/ocfs2/quota_local.c

@@ -702,6 +702,8 @@ static int ocfs2_local_read_info(struct super_block *sb, int type)
 	info->dqi_priv = oinfo;
 	oinfo->dqi_type = type;
 	INIT_LIST_HEAD(&oinfo->dqi_chunk);
+	oinfo->dqi_gqinode = NULL;
+	ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
 	oinfo->dqi_rec = NULL;
 	oinfo->dqi_lqi_bh = NULL;
 	oinfo->dqi_libh = NULL;