Is there a way to tell from "struct dentry" or "struct vfsmount" that whether the directory entries are controllable from userspace's requests or not? TOMOYO wants to use /proc/self/ rather than /proc/$PID/ if $PID matches current thread's process ID in order to prevent current thread from accessing other process's information unless needed. Converting "$PID" to "self" in core code (i.e. __d_path()) was refused in the past, with a response "do the conversion after returning from __d_path()". But since procfs can be mounted on various locations (e.g. /proc/ /proc2/ /p/ /tmp/foo/100/p/ ), the caller of __d_path() (i.e. TOMOYO) cannot tell that whether the numeric part in the returned string represents process ID or not. If TOMOYO traverses the vfsmount tree up manually in order to detect the process ID part, TOMOYO will no longer use __d_path(). Thus, I'm considering to use a different way for representing files on procfs (e.g. proc:$PID/mounts rather than /proc/$PID/mounts) so that TOMOYO can convert "$PID" to "self". That will be possible. There are two types of filesystems. One is filesystems (e.g. ext3 tmpfs nfs) where dentries can be controlled from userspace using creat()/rename()/link() etc. The other is filesystems (e.g. procfs sysfs securityfs) where dentries cannot be controlled from userspace using creat()/rename()/link() etc. Using different way for representing files on only procfs sounds a bit strange. Thus, I'm considering to use a unified way for representing files on the latter type of filesystems (e.g. proc:$PID/mounts sys:power/state ). But I don't know how to tell the former type and the latter type. Is there a way to tell it from "struct dentry" or "struct vfsmount"? Regards. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
