Removing files in devfs

Removing files in devfs

[Oliver Feiler]

Hello,

	Is this behaviour supposed to be?

9:36 root@kiza /dev# l null 
crw-rw-rw-    1 root     root       1,   3 Jan  1  1970 null
9:36 root@kiza /dev# rm null
removing `null'
9:36 root@kiza /dev# l null
ls: null: No such file or directory
9:36 root@kiza /dev#

	I have kernel 2.4.16 with devfs and on every other system I tried I 
only get "rm: cannot unlink `null': Operation not permitted" when trying to 
delete something in devfs. And I cannot see any differences as far as devfs is 
concerned on the systems I tried. devfs compiled in, mounted on boot time, 
same version of devfsd.

Regards,

Oliver

-- 
Oliver Feiler                                               kiza@gmx.net
http://www.lionking.org/~kiza/pgpkey              PGP key ID: 0x561D4FD2
http://www.lionking.org/~kiza/

Re: Removing files in devfs

[Juan Quintela]

>>>>> "oliver" == Oliver Feiler <kiza@gmx.net> writes:

oliver> Hello,
oliver> Is this behaviour supposed to be?

oliver> 9:36 root@kiza /dev# l null 
oliver> crw-rw-rw-    1 root     root       1,   3 Jan  1  1970 null
oliver> 9:36 root@kiza /dev# rm null
oliver> removing `null'
oliver> 9:36 root@kiza /dev# l null
oliver> ls: null: No such file or directory
oliver> 9:36 root@kiza /dev#

oliver> I have kernel 2.4.16 with devfs and on every other system I tried I 
oliver> only get "rm: cannot unlink `null': Operation not permitted" when trying to 
oliver> delete something in devfs. And I cannot see any differences as far as devfs is 
oliver> concerned on the systems I tried. devfs compiled in, mounted on boot time, 
oliver> same version of devfsd.

oliver> Regards,

oliver> Oliver

Since 2.4.16-preX, you can't remove a {file,symlink} in devfs created
by devfs :(

That hit me hardly whith /dev/root.  I had to remove the code that
generate that link to get my system booting (where system is anything
booting with mkinitrd + devfs).

Later, Juan.


-- 
In theory, practice and theory are the same, but in practice they 
are different -- Larry McVoy

Re: Removing files in devfs

[Richard Gooch]

Oliver Feiler writes:
> Hello,
> 
> 	Is this behaviour supposed to be?
> 
> 9:36 root@kiza /dev# l null 
> crw-rw-rw-    1 root     root       1,   3 Jan  1  1970 null
> 9:36 root@kiza /dev# rm null
> removing `null'
> 9:36 root@kiza /dev# l null
> ls: null: No such file or directory
> 9:36 root@kiza /dev#
> 
> 	I have kernel 2.4.16 with devfs and on every other system I
> tried I only get "rm: cannot unlink `null': Operation not permitted"
> when trying to delete something in devfs. And I cannot see any
> differences as far as devfs is concerned on the systems I
> tried. devfs compiled in, mounted on boot time, same version of
> devfsd.

What is "every other system"?

				Regards,

					Richard....
Permanent: rgooch@atnf.csiro.au
Current:   rgooch@ras.ucalgary.ca

Re: Removing files in devfs

[Oliver Feiler]

Richard Gooch wrote:
> 
> What is "every other system"?
> 

	Sorry, the last mail didn't get a followup to the list... that should 
explain it:

----forwarded mail----

>>>>> "oliver" == Oliver Feiler <kiza@gmxpro.net> writes:

oliver> Juan Quintela wrote:
>> 
>> Since 2.4.16-preX, you can't remove a {file,symlink} in devfs created
>> by devfs :(

oliver> Hmm, that'll be it. Since the other systems I tried were both running
oliver> 2.4.17 kernels and I'm with .16 at the moment. Thanks for the hint.  


this patch should make the trick (it is a workaround, but it is not
trivial to do it an easier way without still more incestuous
relations,  Wating for Richard to do something to the respect.

Later, Juan.

diff -u linux/fs/super.c.orig linux/fs/super.c
--- linux/fs/super.c.orig       Fri Jan  4 21:28:24 2002
+++ linux/fs/super.c    Fri Jan  4 21:09:45 2002
@@ -1056,8 +1056,8 @@
        putname(fs_names);
        if (path_start >= 0) {
                name = path + path_start;
-               devfs_mk_symlink (NULL, "root", DEVFS_FL_DEFAULT,
-                                 name + 5, NULL, NULL);
+//             devfs_mk_symlink (NULL, "root", DEVFS_FL_DEFAULT,
+//                               name + 5, NULL, NULL);
                memcpy (name, "/dev/", 5);
        }
        vfsmnt = alloc_vfsmnt();


----end forward----


-- 
Oliver Feiler                                               kiza@gmx.net
http://www.lionking.org/~kiza/pgpkey              PGP key ID: 0x561D4FD2
http://www.lionking.org/~kiza/