Code: void file_sb_list_del(struct file *file)
{
	if (!list_empty(&file->f_u.fu_list)) {
		lg_local_lock_cpu(&files_lglock, file_list_cpu(file));
		list_del_init(&file->f_u.fu_list);
		lg_local_unlock_cpu(&files_lglock, file_list_cpu(file));
	}
}

Vulnerability Type: DoS 
CWE ID: CWE-17
Summary: The filesystem implementation in the Linux kernel before 3.13 performs certain operations on lists of files with an inappropriate locking approach, which allows local users to cause a denial of service (soft lockup or system crash) via unspecified use of Asynchronous I/O (AIO) operations.
Commit Message: get rid of s_files and files_lock

The only thing we need it for is alt-sysrq-r (emergency remount r/o)
and these days we can do just as well without going through the
list of files.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>