remove special TIMEOUT handling from incoming queue

[elogind.git] / FAQ

diff --git a/FAQ b/FAQ
index a3bec17408f2e722fbe2155326faebb51bca8148..bd9d63a4d50ef7e54f8b7041aeb1f8587d146b63 100644 (file)
--- a/FAQ
+++ b/FAQ
@@ -23,7 +23,7 @@ A: To quote Al Viro (Linux VFS kernel maintainer):
        - the former had stayed around for many months with maintainer
          claiming that everything works fine
        - the latter had stayed, period.
-       - the devfs maintainer/author disappeared and stoped maintaining
+       - the devfs maintainer/author disappeared and stopped maintaining
          the code.
 
 Q: But udev will not automatically load a driver if a /dev node is opened
@@ -72,10 +72,6 @@ A: udev is entirely in userspace.  If the kernel supports a greater number
 Q: Will udev support symlinks?
 A: Yes, It now does.  Multiple symlinks per device node too.
 
-Q: How will udev support changes to device permissions?
-A: On shutdown, udev will save the state of existing device permissions to
-   its database, and then used the on the next boot time.
-
 Q: How will udev handle the /dev filesystem?
 A: /dev can be a ramfs, or a backing filesystem.  udev does not care what
    kind of filesystem it runs on.
@@ -84,6 +80,33 @@ Q: How will udev handle devices found before init runs?
 A: udev will be placed in initramfs and run for every device that is found.
    Work to get this implemented is still underway.
 
+Q: Can I use udev to automount a USB device when I connect it?
+A: Technically, yes, but udev is not intended for this. Projects that do
+   automount hotplugged storage devices are:
+     * Usb-mount http://users.actrix.co.nz/michael/usbmount.html
+     * devlabel http://linux.dell.com/projects.shtml#devlabel   
+                                                             
+   Alternatively, it is easy to add the following to fstab:  
+   /udev/pendrive       /pendrive       vfat    user,noauto             0       0
+
+   This means that users can access the device with:
+   $ mount /pendrive
+   And don't have to be root but will get full permissions on /pendrive.
+   This works even without udev if /udev/pendrive is replaced by /dev/sda1
+
+Q: Are there any security issues that I should be aware of?
+A: When using dynamic device numbers, a given pair of major/minor numbers may
+   point to different hardware over time. If a user has permission to access a
+   specific device node directly and is able to create hard links to this node,
+   he or she can do so to create a copy of the device node. When the device is
+   unplugged and udev removes the device node, the user's copy remains.
+   If the device node is later recreated with different permissions the hard 
+   link can still be used to access the device using the old permissions.
+   (The same problem exists when using PAM to change permissions on login.)
+    
+   The simplest solution is to prevent the creation of hard links by putting
+   /dev in a separate filesystem (tmpfs, ramfs, ...).
+    
 Q: I have other questions about udev, where do I ask them?
 A: The linux-hotplug-devel mailing list is the proper place for it.  The
    address for it is linux-hotplug-devel@lists.sourceforge.net