diff options
| -rw-r--r-- | block/blk-mq-debugfs.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index fa31ceaa8de6..21cbc1f071c6 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -697,7 +697,11 @@ static ssize_t blk_mq_debugfs_write(struct file *file, const char __user *buf, const struct blk_mq_debugfs_attr *attr = m->private; void *data = d_inode(file->f_path.dentry->d_parent)->i_private; - if (!attr->write) + /* + * Attributes that only implement .seq_ops are read-only and 'attr' is + * the same with 'data' in this case. + */ + if (attr == data || !attr->write) return -EPERM; return attr->write(data, buf, count, ppos); |