[gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Walter Dnes]

  This may be related to me running mdev instead of udev.  I've been
using /dev/shm for creating and deleting scratch files, to speed things
up when processing photographs with automated scripts.  It used to work.
But now it no longer allows writes by anybody except root.  A couple of
days ago, I did a big update, which resulted in devpts having to be
explicitly mounted.  Since I run mdev instead of udev, the instruction
to "rc-update add udev-mount sysinit" doesn't work for me.  Instead I
put an explicit "mount devpts" in /etc/local.d/000.start, which handles
the automounting.  Anybody else seeing /dev/shm as root-only, or is this
an artifact of my weird setup?

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Dale]

Walter Dnes wrote:
>   This may be related to me running mdev instead of udev.  I've been
> using /dev/shm for creating and deleting scratch files, to speed things
> up when processing photographs with automated scripts.  It used to work.
> But now it no longer allows writes by anybody except root.  A couple of
> days ago, I did a big update, which resulted in devpts having to be
> explicitly mounted.  Since I run mdev instead of udev, the instruction
> to "rc-update add udev-mount sysinit" doesn't work for me.  Instead I
> put an explicit "mount devpts" in /etc/local.d/000.start, which handles
> the automounting.  Anybody else seeing /dev/shm as root-only, or is this
> an artifact of my weird setup?
>


I'm not real sure on what you are doing but, this is what mine is:

root@fireball / # ls -al /dev/shm
total 4
drwxrwxrwt  2 root root    60 Dec  3 18:20 .
drwxr-xr-x 18 root root  4400 Dec 26 18:56 ..
-rwxr-xr-x  1 dale users   32 Dec  3 18:20 sem.lastpassffsemaphore
root@fireball / #

It seems that whatever file is there is owned by the person who created
it.  I use LastPass for my password manager so, I assume, that is what
that is.  Odd tho that I am not currently logged into LastPast but can't
imagine what else could be named that. 

That help any?  Can I get you any other info? 

Dale

:-)  :-) 

-- 
I am only responsible for what I said ... Not for what you understood or how you interpreted my words!

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[William Kenworthy]

On 27/12/12 11:19, Dale wrote:
> Walter Dnes wrote:
>>   This may be related to me running mdev instead of udev.  I've been
>> using /dev/shm for creating and deleting scratch files, to speed things
>> up when processing photographs with automated scripts.  It used to work.
>> But now it no longer allows writes by anybody except root.  A couple of
>> days ago, I did a big update, which resulted in devpts having to be
>> explicitly mounted.  Since I run mdev instead of udev, the instruction
>> to "rc-update add udev-mount sysinit" doesn't work for me.  Instead I
>> put an explicit "mount devpts" in /etc/local.d/000.start, which handles
>> the automounting.  Anybody else seeing /dev/shm as root-only, or is this
>> an artifact of my weird setup?
>>
> 
> 
> I'm not real sure on what you are doing but, this is what mine is:
> 
> root@fireball / # ls -al /dev/shm
> total 4
> drwxrwxrwt  2 root root    60 Dec  3 18:20 .
> drwxr-xr-x 18 root root  4400 Dec 26 18:56 ..
> -rwxr-xr-x  1 dale users   32 Dec  3 18:20 sem.lastpassffsemaphore
> root@fireball / #
> 
> It seems that whatever file is there is owned by the person who created
> it.  I use LastPass for my password manager so, I assume, that is what
> that is.  Odd tho that I am not currently logged into LastPast but can't
> imagine what else could be named that. 
> 
> That help any?  Can I get you any other info? 
> 
> Dale
> 
> :-)  :-) 
> 

moriah ~ # ls -al /dev/shm
total 128
drwxrwxrwt  2 root root       80 Dec 27 13:39 .
drwxr-xr-x 17 root root     4900 Dec 27 12:51 ..
-r--------  1 wdk  wdk  67108904 Dec 27 13:39 pulse-shm-259503987
-r--------  1 wdk  wdk  67108904 Dec 27 13:39 pulse-shm-3719994179
moriah

Do you have the fstab line:
"none /dev/shm tmpfs defaults  0 0"


I also grepped /usr/lib/udev/* and no shm shows in the udev rules there.

The contents of the dir are as Dale sees - I have a couple of
BillK

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Walter Dnes]

On Thu, Dec 27, 2012 at 01:49:01PM +0800, William Kenworthy wrote

> Do you have the fstab line:
> "none /dev/shm tmpfs defaults  0 0"

  I had an ancient version, which I've been copying to new installs for
years.  It was...
shm /dev/shm tmpfs nodev,nosuid,noexec  0 0

  I changed over to your line, and rebooted, but no difference.  I
finally did things the hard way in fstab...

none   /dev/shm    tmpfs rw,noatime,noexec,nosuid,nodev 0 0

...and in /etc/local.d/000.start I've added a chmod line...

#!/bin/bash
mount devpts
chmod 1777 /dev/shm

  Note that on my system, "defaults" in fstab allows scripts to execute
on /dev/shm, which is generally frowned on.  "noexec" blocks that,
notwithstanding the chmod 1777.  Out of sheer curiousity, what happens
when you create file /dev/shm/hello with 2 lines...

#!/bin/bash
echo "Hello World"

...and then you

chmod 755 /dev/shm/hello
/dev/shm/hello

  Does it execute or come back with permission denied?

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[William Kenworthy]

On 28/12/12 11:25, Walter Dnes wrote:
> chmod 755 /dev/shm/hello
> /dev/shm/hello

as a user (not root)

wdk@moriah /home/vm/qemu/mail $ vi /dev/shm/hello
wdk@moriah /home/vm/qemu/mail $ chmod 755 /dev/shm/hello
wdk@moriah /home/vm/qemu/mail $ /dev/shm/hello
Hello World
wdk@moriah /home/vm/qemu/mail $

worked fine.

and

moriah ~ # mount|grep shm
none on /dev/shm type tmpfs (rw,relatime)
moriah ~ #

BillK

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Mike Gilbert]

On Thu, Dec 27, 2012 at 10:25 PM, Walter Dnes <waltdnes@waltdnes.org> wrote:
> On Thu, Dec 27, 2012 at 01:49:01PM +0800, William Kenworthy wrote
>
>> Do you have the fstab line:
>> "none /dev/shm tmpfs defaults  0 0"
>
>   I had an ancient version, which I've been copying to new installs for
> years.  It was...
> shm /dev/shm tmpfs nodev,nosuid,noexec  0 0
>
>   I changed over to your line, and rebooted, but no difference.  I
> finally did things the hard way in fstab...
>

Have you somehow disabled the "localmount" service? That fstab line
should work fine.

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Walter Dnes]

On Fri, Dec 28, 2012 at 02:10:26PM +0800, William Kenworthy wrote
> On 28/12/12 11:25, Walter Dnes wrote:
> > chmod 755 /dev/shm/hello
> > /dev/shm/hello
> 
> as a user (not root)
> 
> wdk@moriah /home/vm/qemu/mail $ vi /dev/shm/hello
> wdk@moriah /home/vm/qemu/mail $ chmod 755 /dev/shm/hello
> wdk@moriah /home/vm/qemu/mail $ /dev/shm/hello
> Hello World
> wdk@moriah /home/vm/qemu/mail $
> 
> worked fine.
> 
> and
> 
> moriah ~ # mount|grep shm
> none on /dev/shm type tmpfs (rw,relatime)
> moriah ~ #

  Are you on regular udev?  I thought that /dev/shm was supposed to be
noexec as a security measure.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Dale]

Walter Dnes wrote:
> On Fri, Dec 28, 2012 at 02:10:26PM +0800, William Kenworthy wrote
>> On 28/12/12 11:25, Walter Dnes wrote:
>>> chmod 755 /dev/shm/hello
>>> /dev/shm/hello
>> as a user (not root)
>>
>> wdk@moriah /home/vm/qemu/mail $ vi /dev/shm/hello
>> wdk@moriah /home/vm/qemu/mail $ chmod 755 /dev/shm/hello
>> wdk@moriah /home/vm/qemu/mail $ /dev/shm/hello
>> Hello World
>> wdk@moriah /home/vm/qemu/mail $
>>
>> worked fine.
>>
>> and
>>
>> moriah ~ # mount|grep shm
>> none on /dev/shm type tmpfs (rw,relatime)
>> moriah ~ #
>   Are you on regular udev?  I thought that /dev/shm was supposed to be
> noexec as a security measure.
>

Here is some info on mine, while you are waiting on William.

root@fireball / # ls -al /dev/shm
total 4
drwxrwxrwt  2 root root    60 Dec  3 18:20 .
drwxr-xr-x 17 root root  4360 Dec 28 15:30 ..
-rwxr-xr-x  1 dale users   32 Dec  3 18:20 sem.lastpassffsemaphore
root@fireball / # equery list udev
 * Searching for udev ...
[IP-] [  ] sys-fs/udev-171-r9:0
root@fireball / #

Does that help any?  If I read that correctly, it is executable.  At
least it is for the one that is there.

Dale

:-)  :-) 

-- 
I am only responsible for what I said ... Not for what you understood or how you interpreted my words!

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[William Kenworthy]

On 29/12/12 08:17, Walter Dnes wrote:
> On Fri, Dec 28, 2012 at 02:10:26PM +0800, William Kenworthy wrote
>> On 28/12/12 11:25, Walter Dnes wrote:
>>> chmod 755 /dev/shm/hello
>>> /dev/shm/hello
>>
>> as a user (not root)
>>
>> wdk@moriah /home/vm/qemu/mail $ vi /dev/shm/hello
>> wdk@moriah /home/vm/qemu/mail $ chmod 755 /dev/shm/hello
>> wdk@moriah /home/vm/qemu/mail $ /dev/shm/hello
>> Hello World
>> wdk@moriah /home/vm/qemu/mail $
>>
>> worked fine.
>>
>> and
>>
>> moriah ~ # mount|grep shm
>> none on /dev/shm type tmpfs (rw,relatime)
>> moriah ~ #
> 
>   Are you on regular udev?  I thought that /dev/shm was supposed to be
> noexec as a security measure.
> 
*  sys-fs/udev
      Latest version available: 196-r1
      Latest version installed: 196-r1
      Size of downloaded files: 1,922 kB
      Homepage:    http://www.freedesktop.org/wiki/Software/systemd
      Description: Linux dynamic and persistent device naming support
(aka userspace devfs)
      License:     LGPL-2.1 MIT GPL-2

*  sys-fs/udev-init-scripts
      Latest version available: 18
      Latest version installed: 18
      Size of downloaded files: 4 kB
      Homepage:    http://www.gentoo.org
      Description: udev startup scripts for openrc
      License:     GPL-2

*  virtual/udev
      Latest version available: 196
      Latest version installed: 196
      Size of downloaded files: 0 kB
      Homepage:
      Description: Virtual for udev implementation and number of its
features
      License:


I am waiting on eudev so I can dump it, but I also recently found
"udevil" and am wondering if anyone can overview it and compare with
eudev ... is it a similar project, or just for user mounting?

BillK

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Bruce Hill]

On Sat, Dec 29, 2012 at 09:35:03AM +0800, William Kenworthy wrote:
> *  sys-fs/udev
>       Latest version available: 196-r1
>       Latest version installed: 196-r1
>       Size of downloaded files: 1,922 kB
>       Homepage:    http://www.freedesktop.org/wiki/Software/systemd
>       Description: Linux dynamic and persistent device naming support
> (aka userspace devfs)
>       License:     LGPL-2.1 MIT GPL-2
> 
> *  sys-fs/udev-init-scripts
>       Latest version available: 18
>       Latest version installed: 18
>       Size of downloaded files: 4 kB
>       Homepage:    http://www.gentoo.org
>       Description: udev startup scripts for openrc
>       License:     GPL-2
> 
> *  virtual/udev
>       Latest version available: 196
>       Latest version installed: 196
>       Size of downloaded files: 0 kB
>       Homepage:
>       Description: Virtual for udev implementation and number of its
> features
>       License:
> 
> 
> I am waiting on eudev so I can dump it, but I also recently found
> "udevil" and am wondering if anyone can overview it and compare with
> eudev ... is it a similar project, or just for user mounting?
> 
> BillK

Go for it!

mingdao@workstation ~/dwhelper $ eshowkw eudev
Keywords for sys-fs/eudev:
           |                           | u   |  
           | a a             p     s   | n   |  
           | l m   h i m m   p s   p   | u s | r
           | p d a p a 6 i p c 3   a x | s l | e
           | h 6 r p 6 8 p p 6 9 s r 8 | e o | p
           | a 4 m a 4 k s c 4 0 h c 6 | d t | o
-----------+---------------------------+-----+-------
      0    | + + + + + + ~ + + + + + + | o 0 | gentoo
      0-r1 | ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ | o   | gentoo
1_beta1-r1 | ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ | o   | gentoo
   9999    | o o o o o o o o o o o o o | o   | gentoo

-- 
Happy Penguin Computers               >')
126 Fenco Drive                       ( \
Tupelo, MS 38801                       ^^
support@happypenguincomputers.com
662-269-2706 662-205-6424
http://happypenguincomputers.com/

Don't top-post: http://en.wikipedia.org/wiki/Top_post#Top-posting

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Walter Dnes]

On Fri, Dec 28, 2012 at 07:23:33PM -0600, Dale wrote

> Here is some info on mine, while you are waiting on William.
> 
> root@fireball / # ls -al /dev/shm
> total 4
> drwxrwxrwt  2 root root    60 Dec  3 18:20 .
> drwxr-xr-x 17 root root  4360 Dec 28 15:30 ..
> -rwxr-xr-x  1 dale users   32 Dec  3 18:20 sem.lastpassffsemaphore
> root@fireball / # equery list udev
>  * Searching for udev ...
> [IP-] [  ] sys-fs/udev-171-r9:0
> root@fireball / #
> 
> Does that help any?  If I read that correctly, it is executable.  At
> least it is for the one that is there.

  Can you create the sample script on /dev/shm, chmod it 755, and try
to run it.  The "noexec" mount option over-rides attributes that chmod
sets.  E.g. on my machine...

[d531][waltdnes][~] chmod 744 /dev/shm/hw
[d531][waltdnes][~] ll /dev/shm/hw
-rwxr--r-- 1 waltdnes users 32 Dec 27 19:10 /dev/shm/hw
[d531][waltdnes][~] /dev/shm/hw
bash: /dev/shm/hw: Permission denied
[d531][waltdnes][~]

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] /dev/shm permissions drwxr-xr-x root:root ?

[Dale]

Walter Dnes wrote:
> On Fri, Dec 28, 2012 at 07:23:33PM -0600, Dale wrote
>
>> Here is some info on mine, while you are waiting on William.
>>
>> root@fireball / # ls -al /dev/shm
>> total 4
>> drwxrwxrwt  2 root root    60 Dec  3 18:20 .
>> drwxr-xr-x 17 root root  4360 Dec 28 15:30 ..
>> -rwxr-xr-x  1 dale users   32 Dec  3 18:20 sem.lastpassffsemaphore
>> root@fireball / # equery list udev
>>  * Searching for udev ...
>> [IP-] [  ] sys-fs/udev-171-r9:0
>> root@fireball / #
>>
>> Does that help any?  If I read that correctly, it is executable.  At
>> least it is for the one that is there.
>   Can you create the sample script on /dev/shm, chmod it 755, and try
> to run it.  The "noexec" mount option over-rides attributes that chmod
> sets.  E.g. on my machine...
>
> [d531][waltdnes][~] chmod 744 /dev/shm/hw
> [d531][waltdnes][~] ll /dev/shm/hw
> -rwxr--r-- 1 waltdnes users 32 Dec 27 19:10 /dev/shm/hw
> [d531][waltdnes][~] /dev/shm/hw
> bash: /dev/shm/hw: Permission denied
> [d531][waltdnes][~]
>

Mine does this:

root@fireball / # chmod 755 /dev/shm/hello
root@fireball / # /dev/shm/hello
-su: /dev/shm/hello: Permission denied
root@fireball / # ls -al /dev/shm/hello 
-rwxr-xr-x 1 root root 31 Dec 28 23:08 /dev/shm/hello
root@fireball / #  cat /etc/fstab | grep shm
# glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for 
# POSIX shared memory (shm_open, shm_unlink).
shm                     /dev/shm        tmpfs           nodev,nosuid,noexec     0 0
root@fireball / #

So I get permission denied too.  I did that as root to I might add in
case you don't notice.

That help?

Dale

:-)  :-) 

-- 
I am only responsible for what I said ... Not for what you understood or how you interpreted my words!