Debian Bug report logs - #476519
su - nobody sometimes logged back out instantly

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Message #5 received at submit@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: submit@bugs.debian.org

Subject: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 17:23:48 +0800

Package: login
Version: 1:4.1.1-1
Severity: wishlist

Sometimes just after I do "su - nobody", I get instantly logged back out.
It's like I accidentally sent a ^D to the shell.

At first I thought it might be my emacs shell buffer sending junk, but
it happens in xterm too.
And it happens or doesn't happen without any pattern as to when.

And there's nothing funny in /var/log/auth.log.

Sorry if you can't reproduce it. Just wanted to let you know. Below we
see one bad and two goods.

# su - nobody
No directory, logging in with HOME=/
nobody@jidanni1:/$ logout <--------------I did not type this.
17:02 ~# su -l nobody
No directory, logging in with HOME=/
nobody@jidanni1:/$ exit
logout
17:02 ~# su -l nobody
No directory, logging in with HOME=/
nobody@jidanni1:/$ exit
logout

Yes, I typed the "exit"s. -l or - have the same probability.

Maybe there's a race condition that sometimes kills such a shell?

Message #10 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 13:47:15 +0200

[Message part 1 (text/plain, inline)]

tags 476519 unreproducible
thanks

Hello,

On Thu, Apr 17, 2008 at 05:23:48PM +0800, jidanni@jidanni.org wrote:
> 
> Sometimes just after I do "su - nobody", I get instantly logged back out.
> It's like I accidentally sent a ^D to the shell.

I could not reproduce it in my terminals, even in a few 1000s of tries.

Could you try with the attached expect script?

Best Regards,
-- 
Nekral

[test.exp (text/plain, attachment)]

Message #17 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 19:58:19 +0800

Thanks, I tried your script with
PS1=#\  ENV= HOME=/tmp ./test.exp
but for 20 instead of 2000 passes, but didn't trigger the bug.
Maybe there are some bugs expect(1) cannot trigger like real users.
Yes it is a mystery to me.

Message #22 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Justin Pryzby <justinpryzby@users.sourceforge.net>

To: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: Bug#476519: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 08:18:00 -0400

On Thu, Apr 17, 2008 at 07:58:19PM +0800, jidanni@jidanni.org wrote:
> Thanks, I tried your script with
> PS1=#\  ENV= HOME=/tmp ./test.exp
> but for 20 instead of 2000 passes, but didn't trigger the bug.
> Maybe there are some bugs expect(1) cannot trigger like real users.
> Yes it is a mystery to me.
Do you have any signal handling customization in your shell rc files?
What does stty -a say (I'm thinking of tostop)?

Message #27 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: justinpryzby@users.sourceforge.net

Cc: 476519@bugs.debian.org

Subject: Re: Bug#476519: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 20:45:00 +0800

> Do you have any signal handling customization in your shell rc files?
> What does stty -a say (I'm thinking of tostop)?

# stty -a
speed 38400 baud; rows 39; columns 111; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>;
start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke
# trap
#

Plus su - nobody shouldn't read any rc files, as nobody has no home
directory to put them.

In /var/log/auth.log, note the seconds:
Apr 17 20:36:30 jidanni1 su[11105]: Successful su for nobody by root
Apr 17 20:36:30 jidanni1 su[11105]: + pts/1 root:nobody
Apr 17 20:36:30 jidanni1 su[11105]: pam_unix(su:session): session opened for user nobody by jidanni(uid=0)
Apr 17 20:36:30 jidanni1 su[11105]: pam_unix(su:session): session closed for user nobody
Apr 17 20:36:33 jidanni1 su[11109]: Successful su for nobody by root
Apr 17 20:36:33 jidanni1 su[11109]: + pts/1 root:nobody
Apr 17 20:36:33 jidanni1 su[11109]: pam_unix(su:session): session opened for user nobody by jidanni(uid=0)
Apr 17 20:36:34 jidanni1 su[11109]: pam_unix(su:session): session closed for user nobody

Here we see me getting logged off the same second I login -- bad. Then three
seconds later I hit ^P RET and one second after that ^D -- normal.

Message #32 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 17 Apr 2008 20:38:06 +0200

On Thu, Apr 17, 2008 at 07:58:19PM +0800, jidanni@jidanni.org wrote:
> Thanks, I tried your script with
> PS1=#\  ENV= HOME=/tmp ./test.exp
> but for 20 instead of 2000 passes, but didn't trigger the bug.
> Maybe there are some bugs expect(1) cannot trigger like real users.
> Yes it is a mystery to me.

I could not reproduce it when run by hand neither.

Could you reproduce it with another user?
Could you reproduce it with another terminal (console)?
Are you using special PAM modules?

You mentioned no messages in /var/log/auth.log, are there messages in
/var/log/syslog?

What's your probability of occurrence? (1 out of 3?)

Can you try to get a systrace of su when it fails and compare it with a
successful session.

-- 
Nekral

Message #37 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: svenjoac@gmx.de, 476519@bugs.debian.org

Cc: bug-gnu-emacs@gnu.org, nicolas.francois@centraliens.net

Subject: Re: shell-mode garbles input

Date: Fri, 18 Apr 2008 19:38:35 +0800

SJ> Please try the following:
SJ> log in as root on the console, type su - nobody (getting the "No
SJ> directory,..." message above) and type e.  Without hitting return, I got
SJ> the message: -su: e: command not found.

Holy moly, I can reproduce that. I apologize to emacs & co. It is a su bug.

Dear http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=476519 team:
please see
http://lists.gnu.org/archive/html/bug-gnu-emacs/2008-04/msg00080.html
First fix that and then maybe 476519 will get fixed in the process.

Regarding 476519:
NF> Could you reproduce it with another user?
No, but yes with the "e" bug.
NF> Could you reproduce it with another terminal (console)?
tty1: no, but didn't try hard. "e" bug: yes.
NF> Are you using special PAM modules?
I don't know, I just installed vanilla sid several years ago and don't
play around with the advanced parts.
NF> You mentioned no messages in /var/log/auth.log,
Just the normal ones I posted. On a different machine I get
  pam_env(su:session): Unable to open env file: /etc/environment: No
  such file or directory
but that doesn't affect if the bug occurs or not.
NF> are there messages in /var/log/syslog?
No.
NF> What's your probability of occurrence? (1 out of 3?)
Seems to come in clumps... maybe 5 bads in a row, then good until
close the shell window. But not always.
Or bad to nobody, good to user2, then bad to nobody.
NF> Can you try to get a systrace of su when it fails and compare it with a
NF> successful session.
If you mean strace, well, whenever I try it the bug doesn't occur,
under strace.

Anyway, fix the "e" bug and maybe 476519 will get fixed in the
process. Actually, it's the first character typed, and not just "e".

Message #42 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sat, 19 Apr 2008 15:04:24 +0200

Hello,

I can't reproduce it neither with emacs nor the "first character" bug.

Another idea: What is the shell used by root or by nobody once logged in
(echo $SHELL), and what's the default shell on the system?

-- 
Nekral

Message #47 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: Nicolas Fran?ois <nicolas.francois@centraliens.net>

Cc: 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sun, 20 Apr 2008 07:16:55 +0800

Sven, can you help out with
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=476519
I am "out of the office" this week.

On Sat, Apr 19, 2008 at 03:04:24PM +0200, Nicolas Fran?ois wrote:
> Hello,
> 
> I can't reproduce it neither with emacs nor the "first character" bug.
> 
> Another idea: What is the shell used by root or by nobody once logged in
> (echo $SHELL), and what's the default shell on the system?

Message #52 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Sven Joachim <svenjoac@gmx.de>

To: jidanni@jidanni.org

Cc: Nicolas Fran?ois <nicolas.francois@centraliens.net>, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Wed, 23 Apr 2008 08:58:42 +0200

I've played a bit around with this bug.  Meanwhile bash got upgraded to
3.2 and behaves somewhat differently: when logging in as root on the
console and typing "su - nobody", nobody is immediately logged out on
the first keystroke, as if C-d had been typed.  However, I could not
reproduce it after moving /root/.bashrc out of the way.  I figured out
that sourcing /etc/bash_completion triggers the problem with the
following minimal /root/.profile and no /root/.bashrc:

--8<---------------cut here---------------start------------->8---
# ~/.profile: executed by Bourne-compatible login shells.

if [ -f ~/.bashrc ]; then
  . ~/.bashrc
fi

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
export PATH

mesg n
--8<---------------cut here---------------end--------------->8---

Here root's shell is /bin/bash and nobody's is /bin/sh, symlinked to
/bin/bash.  Maybe this is a bash issue after all.

Sven

Message #57 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: bug-bash@gnu.org

Cc: nicolas.francois@centraliens.net, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 02 May 2008 06:08:41 +0800

As http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=476519 says, maybe
it is a bash bug: with Debian sid's BASH_VERSION=3.2.33(1)-release
about half the time the below works normally, the other half some
magic hand sends "exit" to it, logging me out right away. The first
letter of which gets bitten off or something, here in an emacs shell window:
03:44 ~# env - su - nobody
bash: xit: command not found
(I do not have the bash-completion package installed, as per
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468858 )

Message #62 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

To: jidanni@jidanni.org

Cc: bug-bash@gnu.org, svenjoac@gmx.de, 476519@bugs.debian.org, nicolas.francois@centraliens.net

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 2 May 2008 11:41:15 +0100

On Fri, May 02, 2008 at 06:08:41AM +0800, jidanni@jidanni.org wrote:
> As http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=476519 says, maybe
> it is a bash bug: with Debian sid's BASH_VERSION=3.2.33(1)-release
> about half the time the below works normally, the other half some
> magic hand sends "exit" to it, logging me out right away. The first
> letter of which gets bitten off or something, here in an emacs shell window:
> 03:44 ~# env - su - nobody
> bash: xit: command not found
> (I do not have the bash-completion package installed, as per
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468858 )

Try

sudo env -i SHELLOPTS=xtrace su -p - nobody

nobody's shell is sh (being bash) or bash, right?

$ getent passwd nobody
nobody:x:65534:65534:nobody:/nonexistent:/bin/sh

$ dpkg -S "$(command -v su)"
login: /bin/su

Which su is your su? Is it using PAM?

$ ldd /bin/su
        linux-gate.so.1 =>  (0xb8021000)
        libpam.so.0 => /lib/libpam.so.0 (0xb7fed000)
        libpam_misc.so.0 => /lib/libpam_misc.so.0 (0xb7fea000)
        libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb7e9c000)
        libdl.so.2 => /lib/i686/cmov/libdl.so.2 (0xb7e98000)
        /lib/ld-linux.so.2 (0xb8022000)

$ grep '^[^#]' /etc/pam.d/su
auth       sufficient pam_rootok.so
session       required   pam_env.so readenv=1
session       required   pam_env.so readenv=1 envfile=/etc/default/locale
session    optional   pam_mail.so nopen
@include common-auth
@include common-account
@include common-session

(also check the included files).

-- 
Stéphane

Message #67 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: stephane_chazelas@yahoo.fr

Cc: bug-bash@gnu.org, svenjoac@gmx.de, 476519@bugs.debian.org, nicolas.francois@centraliens.net

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 02 May 2008 23:27:00 +0800

SC> Try
SC> sudo env -i SHELLOPTS=xtrace su -p - nobody
(I don't use sudo)
uid=0(root) gid=0(root) groups=0(root)
# env -i SHELLOPTS=xtrace su -p - nobody
+ PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
+ '[' /bin/sh ']'
+ PS1='\u@\h:\w\$ '
+ export PATH
+ umask 022
nobody@jidanni2:/root$ kill -1 $$
+ kill -1 6215
# env -i SHELLOPTS=xtrace su -p - nobody
+ PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
+ '[' /bin/sh ']'
+ PS1='\u@\h:\w\$ '
+ export PATH
+ umask 022
nobody@jidanni2:/root$ logout
#

Above on my first attempt the shell stayed alive, so I typed kill -1
$$ (instead of exit, so it would be clear that I typed it, as that is
something the "magic hand" never uses.) On the second and later
attempts, some magic hand typed "logout" for me. The magic hand also
sometimes types "exit"...

SC> nobody's shell is sh (being bash) or bash, right?
SC> $ getent passwd nobody
SC> nobody:x:65534:65534:nobody:/nonexistent:/bin/sh
Same here.
SC> $ dpkg -S "$(command -v su)"
SC> login: /bin/su
Same here.
$ ls -og /bin/sh
lrwxrwxrwx 1 4 2008-04-29 07:04 /bin/sh -> bash
SC> Which su is your su? Is it using PAM?
SC> $ ldd /bin/su
same here except for the hex numbers.
SC> $ grep '^[^#]' /etc/pam.d/su
Same here.
SC> (also check the included files).
Never touched them.
$ cd /etc/pam.d&&find * -atime -1 -type f|xargs ls -og
-rw-r--r-- 1  392 2005-07-26 16:48 common-account
-rw-r--r-- 1  436 2005-07-26 16:48 common-auth
-rw-r--r-- 1 1097 2005-07-26 16:48 common-password
-rw-r--r-- 1  372 2005-07-26 16:48 common-session
-rw-r--r-- 1  289 2005-07-05 22:45 cron
-rw-r--r-- 1 2843 2006-09-17 15:22 login
-rw-r--r-- 1  520 2003-09-01 06:21 other
-rw-r--r-- 1 2305 2006-07-14 19:05 su
-rw-r--r-- 1  289 2007-08-13 23:54 xdm
The only thing I tampered with is probably just making a
$ ls -og /etc/environment
-rw-r--r-- 1 0 2008-05-02 03:37 /etc/environment
to stop the warning in /var/log/auth.log if it is absent.
The pam stuff came with my Debian sid installation and apt-get says
removing it "should NOT be done unless you know exactly what you are
doing!" i.e., not me, so I dare not touch it.

Message #72 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

To: jidanni@jidanni.org

Cc: nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 2 May 2008 16:50:53 +0100

On Fri, May 02, 2008 at 11:27:00PM +0800, jidanni@jidanni.org wrote:
> SC> Try
> SC> sudo env -i SHELLOPTS=xtrace su -p - nobody
> (I don't use sudo)
> uid=0(root) gid=0(root) groups=0(root)
> # env -i SHELLOPTS=xtrace su -p - nobody
> + PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
> + '[' /bin/sh ']'
> + PS1='\u@\h:\w\$ '
> + export PATH
> + umask 022
> nobody@jidanni2:/root$ kill -1 $$
> + kill -1 6215
> # env -i SHELLOPTS=xtrace su -p - nobody
> + PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
> + '[' /bin/sh ']'
> + PS1='\u@\h:\w\$ '
> + export PATH
> + umask 022
> nobody@jidanni2:/root$ logout
> #
> 
> Above on my first attempt the shell stayed alive, so I typed kill -1
> $$ (instead of exit, so it would be clear that I typed it, as that is
> something the "magic hand" never uses.) On the second and later
> attempts, some magic hand typed "logout" for me. The magic hand also
> sometimes types "exit"...
[...]

Does that happen straight away or after a delay?

The "logout" thing looks a bit like eof from the terminal.

It could be the "read" being interupted by a signal or something
like that.

strace would probably help then:

sudo env -i strace -vfo /tmp/strace.out /bin/su - nobody

And look at the last read(0 in /tmp/strace.out

It could be worth checking the ulimits as well.

-- 
Stéphane

Message #77 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

To: jidanni@jidanni.org

Cc: bug-bash@gnu.org, svenjoac@gmx.de, 476519@bugs.debian.org, nicolas.francois@centraliens.net

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 2 May 2008 16:56:52 +0100

On Fri, May 02, 2008 at 11:27:00PM +0800, jidanni@jidanni.org wrote:
> SC> Try
> SC> sudo env -i SHELLOPTS=xtrace su -p - nobody
> (I don't use sudo)
> uid=0(root) gid=0(root) groups=0(root)
> # env -i SHELLOPTS=xtrace su -p - nobody
> + PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
> + '[' /bin/sh ']'
> + PS1='\u@\h:\w\$ '
> + export PATH
> + umask 022
> nobody@jidanni2:/root$ kill -1 $$
> + kill -1 6215
> # env -i SHELLOPTS=xtrace su -p - nobody
> + PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
> + '[' /bin/sh ']'
> + PS1='\u@\h:\w\$ '
> + export PATH
> + umask 022
> nobody@jidanni2:/root$ logout
> #
[...]

Could be a tty setting as well.

stty min 0 time 10 -icanon

could reproduce that if bash was built without readline I think.
With readline, bash is meant to reset those min and time
parameters before each prompt. Maybe it fails to do so in which
case strace will tell you as well.

What does stty -a tell you?

-- 
Stéphane

Message #82 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: stephane_chazelas@yahoo.fr

Cc: nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sat, 03 May 2008 00:30:02 +0800

Here we see the typical deal. You asked me about ulimit. I tried to
get a shell oh, six times this time before the magic hand stopped
logging me out. Whereupon it bites off the first character of what I
type and logs me out, saving the message for after the next prompt.
Then I get a shell again to give you the answer.

# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ ulimit
logout
# su - nobody
bash: limit: command not found
# No directory, logging in with HOME=/
nobody@jidanni2:/$ ulimit
unlimited
nobody@jidanni2:/$ stty
speed 38400 baud; line = 0;
erase = <undef>; kill = <undef>;
-brkint -imaxbel
-onlcr
-echo

Happens also in xterm, where
# stty
speed 38400 baud; line = 0;
-brkint -imaxbel iutf8

SC> Does that happen straight away or after a delay?

The logout happens instantaneously, no waiting for me to type my first
command as nobody.

SC> The "logout" thing looks a bit like eof from the terminal.

Very much so.

SC> strace would probably help then:

No. Every time I use strace I get a shell that sticks around. The bug
is not triggered. I'll send you one anyway.

SC> And look at the last read(0 in /tmp/strace.out

SC> Could be a tty setting as well.

SC> stty min 0 time 10 -icanon

Ho ho ho, that even eats through all the shells stacked up in my emacs
shell buffer exiting each one.

SC> With readline
Has readline. I'll send you shopt output.

Message #87 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Chet Ramey <chet.ramey@case.edu>

To: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

Cc: jidanni@jidanni.org, nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de, chet.ramey@case.edu

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 02 May 2008 12:50:49 -0400

Stephane Chazelas wrote:
[...]
> 
> Could be a tty setting as well.
> 
> stty min 0 time 10 -icanon
> 
> could reproduce that if bash was built without readline I think.
> With readline, bash is meant to reset those min and time
> parameters before each prompt. Maybe it fails to do so in which
> case strace will tell you as well.

You beat met to it. :-)  Does this happen only in an emacs shell-mode
window?  If that is the case, then readline doesn't enter into the
picture -- bash disables line editing when it can tell it's being run
by emacs -- and uses read(2).  read can return failure right away
(-1/EAGAIN) or 0 (no data available) if it's called with the tty in
non-canonical mode and those tty settings.  Either value will be
translated to EOF and cause the shell to exit.

Chet

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		       Live Strong.  No day but today.
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/

Message #92 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: chet.ramey@case.edu

Cc: stephane_chazelas@yahoo.fr, nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sat, 03 May 2008 01:04:56 +0800

CR> Does this happen only in an emacs shell-mode window?
No. It happens also in xterm. Today it at least allowed me to do -c
date. I did not type exit or logout. The magic hand did.
# su - nobody -c date
No directory, logging in with HOME=/
Sat May  3 01:03:10 CST 2008
# su - nobody -c 'sh -i'
No directory, logging in with HOME=/
sh-3.2$ exit
# su - nobody
No directory, logging in with HOME=/
nobody@jidanni2:/$ logout
#

Message #97 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

To: jidanni@jidanni.org

Cc: nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Fri, 2 May 2008 21:58:50 +0100

On Sat, May 03, 2008 at 12:30:02AM +0800, jidanni@jidanni.org wrote:
> Here we see the typical deal. You asked me about ulimit.
[..]

Could you try ulimit -a?

Have you got a lot of processes running as "nobody"?

$ ps -fjlLunobody

$ sudo lsof -u nobody

Or maybe it could be "su" that exits and bash gets killed
because it is orphaned or something like that?

Too many processes running as root? You would see other
problems. Could be the number of open files by the process.

Do you get it from the Linux console (emacs -nw)?

Have you tried changing nobody's shell?

-- 
Stéphane

Message #102 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Chet Ramey <chet.ramey@case.edu>

To: jidanni@jidanni.org

Cc: svenjoac@gmx.de, stephane_chazelas@yahoo.fr, bug-bash@gnu.org, 476519@bugs.debian.org, nicolas.francois@centraliens.net, chet.ramey@case.edu

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sat, 03 May 2008 12:11:38 -0400

jidanni@jidanni.org wrote:
> CR> Does this happen only in an emacs shell-mode window?
> No. It happens also in xterm. Today it at least allowed me to do -c
> date. I did not type exit or logout. The magic hand did.
> # su - nobody -c date
> No directory, logging in with HOME=/
> Sat May  3 01:03:10 CST 2008
> # su - nobody -c 'sh -i'
> No directory, logging in with HOME=/
> sh-3.2$ exit
> # su - nobody
> No directory, logging in with HOME=/
> nobody@jidanni2:/$ logout

FWIW, I can't reproduce this on Fedora 8, the version of Linux I have
available.  This really looks like a terminal process group problem --
read will return -1/EIO if the process doing the read isn't in the same
process group as the terminal and the process is blocking SIGTTIN, which
interactve shells do by default.  Does su do anything with process
groups?

Chet


-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		       Live Strong.  No day but today.
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/

Message #107 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: stephane_chazelas@yahoo.fr

Cc: nicolas.francois@centraliens.net, bug-bash@gnu.org, 476519@bugs.debian.org, svenjoac@gmx.de

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sun, 04 May 2008 10:14:26 +0800

SC> Could you try ulimit -a?
#  su - nobody -c ulimit\ -a|grep -v unlimited
core file size          (blocks, -c) 0
scheduling priority             (-e) 0
pending signals                 (-i) 1791
max locked memory       (kbytes, -l) 32
open files                      (-n) 1024
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
max user processes              (-u) 1791
No directory, logging in with HOME=/

# ps -fjlLunobody; lsof -u nobody
both show nothing. No lots of processes for me.
SC> Do you get it from the Linux console (emacs -nw)?
Yes, just tired it in emacs -nw -f shell and after 10 good logins I got a
bad one.
SC> Have you tried changing nobody's shell?
I don't want to.
CR> Does su do anything with process groups?
That is an advanced question not for little me.

Anyway, the only other human to have reproduced any of this mess is
http://bugs.debian.org/476519#52
Nobody :-) has responded to the points of that message #52.

Message #112 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stephane Chazelas <Stephane_Chazelas@yahoo.fr>

To: jidanni@jidanni.org

Cc: svenjoac@gmx.de, bug-bash@gnu.org, 476519@bugs.debian.org, nicolas.francois@centraliens.net

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Sun, 4 May 2008 17:14:16 +0100

On Sun, May 04, 2008 at 10:14:26AM +0800, jidanni@jidanni.org wrote:
[...]
> SC> Have you tried changing nobody's shell?
> I don't want to.

Then, can you try:

su - nobody -c ksh
su - nobody -c pdksh
su - nobody -c zsh

Also, what about:

perl -e '$<=$>=$(=$)=65534; exec sh'
perl -e '$<=$>=$(=$)=65534; system sh'

> CR> Does su do anything with process groups?
> That is an advanced question not for little me.

Not as far as the strace output can tell.

> Anyway, the only other human to have reproduced any of this mess is
> http://bugs.debian.org/476519#52
> Nobody :-) has responded to the points of that message #52.

The poster seems to say that what makes a difference is what
*root* does before calling su.

That would be /etc/bash_completion? Not sure how what
bash_completion does could have an impact on su.

You've already ruled out the environment by running "env -i",
you could check the open files with lsof -p "$$", you've
already checked stty -a. You could try running ps to see if it
left some processes running behind.

I see "mesg n" in Sven's post.

That command is meant to change the tty permissions to allow
writes to the owner only, in that case root, but I can't see how
that could affect nobody's sh.

For sh to get a SIGTTIN upon the "read", it would have not to be
in the foreground process group of the terminal.

bash does put itself in the foreground process group by a:
ioctl(255, TIOCSPGRP, getpid())
255 being a dup(dup(2)).

And it reads from 0.

So one way to get that behavior could be if stderr is
redirected to a different terminal as stdin... seems like a bit
far fetched.

running out of ideas here...

-- 
Stéphane

Message #117 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: stephane_chazelas@yahoo.fr

Cc: svenjoac@gmx.de, bug-bash@gnu.org, 476519@bugs.debian.org, nicolas.francois@centraliens.net

Subject: Re: [Pkg-shadow-devel] Bug#476519: shell-mode garbles input

Date: Tue, 06 May 2008 05:50:25 +0800

All I have installed else is dash: 4 successes 0 failures.
SC> perl -e '$<=$>=$(=$)=65534; exec sh'
That gets a shell without triggering the error.
SC> perl -e '$<=$>=$(=$)=65534; system sh'
That filled emacs with \377's with luckily a little CPU left over that
I could kill emacs... *
SC> Not sure how what bash_completion does could have an impact on su.
I observed the bug with and without the bash-completion package installed.
# lsof -p $$|wc -l
18
pstree shows no processes running left behind.
I observe the bug with both mesg y and n
SC> running out of ideas here...
Me too so I hereby wait for Sven to chime in with what else he sees.

*This side issue only happened in emacs's shell, (and not with
LC_ALL=C, but yes with my zh locale) and is one of the reasons I now
use a different HISTORY file there... piped thru cat -v.
# sleep 22 && kill -1 $$& #Safety first, also makes the \377s go away.
[1] 16017
# perl -we '$<=$>=$(=$)=65534;system q(sh)'
05:40 ~$ Use "exit" to leave the shell.
05:40 ~$ sh: syntax error near unexpected token `('
05:40 258 ~$ sh:M-CM-^CM-BM-^@0: command not found
05:40 127 ~$ sh: syntax error near unexpected token `('

Anyway, no I don't believe in UFOs. Never mind this side issue. Bye.

Message #122 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: jidanni@jidanni.org, svenjoac@gmx.de

Cc: 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Tue, 13 May 2008 13:38:34 +0200

Hello,

On Thu, Apr 17, 2008 at 05:23:48PM +0800, jidanni@jidanni.org wrote:
> 
> Sometimes just after I do "su - nobody", I get instantly logged back out.
> It's like I accidentally sent a ^D to the shell.
> 
> # su - nobody
> No directory, logging in with HOME=/
> nobody@jidanni1:/$ logout <--------------I did not type this.

I received a similar bug report:
 http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006585.html
 http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006587.html

It was reported to appear on kernel 2.6.24.5 and 2.6.25, on i386
single processor systems.

It was reported to be OK with kernel 2.6.18, 2.6.23.16 or on x86_84 or on
multi-processor systems.

Jidanni and Sven, do you see similarities in your configuration and the
ones used by Siim (mentioned in the above links)

-- 
Nekral

Message #127 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Sven Joachim <svenjoac@gmx.de>

To: Nicolas François <nicolas.francois@centraliens.net>

Cc: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Tue, 13 May 2008 16:26:52 +0200

On 2008-05-13 13:38 +0200, Nicolas François wrote:

> On Thu, Apr 17, 2008 at 05:23:48PM +0800, jidanni@jidanni.org wrote:
>> 
>> Sometimes just after I do "su - nobody", I get instantly logged back out.
>> It's like I accidentally sent a ^D to the shell.
>> 
>> # su - nobody
>> No directory, logging in with HOME=/
>> nobody@jidanni1:/$ logout <--------------I did not type this.
>
> I received a similar bug report:
>  http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006585.html
>  http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006587.html
>
> It was reported to appear on kernel 2.6.24.5 and 2.6.25, on i386
> single processor systems.
>
> It was reported to be OK with kernel 2.6.18, 2.6.23.16 or on x86_84 or on
> multi-processor systems.
>
> Jidanni and Sven, do you see similarities in your configuration and the
> ones used by Siim (mentioned in the above links)

Yes, I have kernel 2.6.24.6 and an i386 single processor system.  Can
try different kernels, but no SMP or 64 bit system -- unless you send me
the money to buy one, that is. ;-)

Sven

Message #132 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: svenjoac@gmx.de

Cc: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Wed, 14 May 2008 00:34:04 +0200

On Tue, May 13, 2008 at 04:26:52PM +0200, svenjoac@gmx.de wrote:
> On 2008-05-13 13:38 +0200, Nicolas François wrote:
> 
> > On Thu, Apr 17, 2008 at 05:23:48PM +0800, jidanni@jidanni.org wrote:
> >> 
> >> Sometimes just after I do "su - nobody", I get instantly logged back out.
> >> It's like I accidentally sent a ^D to the shell.
> >> 
> >> # su - nobody
> >> No directory, logging in with HOME=/
> >> nobody@jidanni1:/$ logout <--------------I did not type this.
> >
> > I received a similar bug report:
> >  http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006585.html
> >  http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006587.html
> >
> > It was reported to appear on kernel 2.6.24.5 and 2.6.25, on i386
> > single processor systems.
> >
> > It was reported to be OK with kernel 2.6.18, 2.6.23.16 or on x86_84 or on
> > multi-processor systems.
> >
> > Jidanni and Sven, do you see similarities in your configuration and the
> > ones used by Siim (mentioned in the above links)
> 
> Yes, I have kernel 2.6.24.6 and an i386 single processor system.

For the record, I'm running a Debian kernel 2.6.24-6, or 2.6.23-1~mtu1
on a Intel(R) Core(TM)2 Duo CPU     E6550

(According to its changelog, 2.6.24-6 seems to be a 2.6.24.4)

So I might be using a too old kernel to reproduce the bug, or it does not
occur on dual cores.


Are you using a Debian kernel? Or an home-compiled kernel?

> Can
> try different kernels, but no SMP or 64 bit system -- unless you send me
> the money to buy one, that is. ;-)

If instead of receiving answers by email, I receive computer to reproduce
this bug, I will share with you ;)

-- 
Nekral

Message #137 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Sven Joachim <svenjoac@gmx.de>

To: Nicolas François <nicolas.francois@centraliens.net>

Cc: jidanni@jidanni.org, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Wed, 14 May 2008 08:49:45 +0200

On 2008-05-14 00:34 +0200, Nicolas François wrote:

> For the record, I'm running a Debian kernel 2.6.24-6, or 2.6.23-1~mtu1
> on a Intel(R) Core(TM)2 Duo CPU     E6550
>
> (According to its changelog, 2.6.24-6 seems to be a 2.6.24.4)
>
> So I might be using a too old kernel to reproduce the bug, or it does not
> occur on dual cores.

2.6.24.4 should not be too old, when the bug was reported four weeks ago
I ran it myself.

> Are you using a Debian kernel? Or an home-compiled kernel?

Home-compiled.

Cheers,
       Sven

Message #142 received at 476519@bugs.debian.org (full text, mbox, reply):

From: jidanni@jidanni.org

To: nicolas.francois@centraliens.net

Cc: svenjoac@gmx.de, 476519@bugs.debian.org

Subject: Re: [Pkg-shadow-devel] Bug#476519: su - nobody sometimes logged back out instantly

Date: Thu, 15 May 2008 10:00:18 +0800

Yes, those
http://lists.alioth.debian.org/pipermail/pkg-shadow-devel/2008-May/006589.html
etc. are all the same bug. You can merge them. It says
>  it does not occur on ibm laptops
yes it does, and also on
          product: AMD Duron(tm) processor
          size: 1GHz
$ COLUMNS=1111 dlocate -l linux-image|perl -alnwe 'print "@F[0,1]" if /^ii/'
ii linux-image-2.6-686
ii linux-image-2.6.24-1-686
ii linux-image-686

Message #147 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Nicolas François <nicolas.francois@centraliens.net>

To: bash@packages.debian.org, 476519@bugs.debian.org

Cc: 476519-submitter@bugs.debian.org

Subject: EIO received by bash when reading the character

Date: Sun, 27 Jul 2008 00:42:42 +0200

[Message part 1 (text/plain, inline)]

notfound 476519 1:4.1.1-1
tags 476519 -unreproducible
reassign 476519 bash
found 476519 3.2-4
thanks

I finally could reproduce this bug on one machine (not all), with:
 * su - nobody
 * perl -e '$<=$>=$(=$)=65534; system bash'
   + from an su - root session
   + from an ssh root session
sometimes, I get a "exit" message and return to the original shell,
sometimes, I get a prompt ("$ "), but it fails after I type the first
           character,
sometimes, I get a valid shell for the user nobody.

Thus I don't think su is involved in this bug, but this looks more like a
bash bug.

I tried to reproduce it with an strace, but could not, however I could
reproduce it with an strace and the execution of bash --noediting.
(see the attached strace.ok and strace.fail logs)
I did not find any useful differences between these two strace logs.

Best Regards,
-- 
Nekral

[strace.ok (text/plain, attachment)]

[strace.fail (text/plain, attachment)]

Message #163 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Hans van Kranenburg <hans.van.kranenburg@mendix.nl>

To: 476519@bugs.debian.org

Subject: Re: [...] sometimes logged back out instantly

Date: Wed, 03 Dec 2008 23:35:59 +0100

Hi,

I can reproduce this on a fresh installed Lenny box (mung'd host/users):

user@homer:~/ 0-$ su
homer:/home/guard/ 0-# iexit     <- i'm typing 'iptables', but get
user@host:~/ 0-$ ptables -L         kicked out almost immediately
-bash: ptables: command not found
user@host:~/ 0-$

/var/log/auth.log displays:
Dec  3 17:14:16 host su[2590]: Successful su for root by user
Dec  3 17:14:16 host su[2590]: + pts/0 guard:root
Dec  3 17:14:16 host su[2590]: pam_unix(su:session): session opened for 
user root by user(uid=1000)
Dec  3 17:14:18 host su[2590]: pam_unix(su:session): session closed for 
user root

Just like Nicolas wrote in #147 in this bugreport: "sometimes, I get a 
"exit" message and return to the original shell, sometimes, I get a 
prompt but it fails after I type the first character, sometimes, I get a 
valid shell" Which of the 3 happens seems completely random.

I've seen this behaviour on one other box, but on another dozen I 
administer daily (with afaik identical configuration) it does never ever 
happen.

If I can help or do more specific test, let me know.

Hans van Kranenburg

P.S.:

Linux host 2.6.26-1-xen-amd64 #1 SMP Sat Nov 8 21:20:04 UTC 2008 x86_64 
GNU/Linux

ii  linux-image-2.6.26-1-xen-amd64      2.6.26-10
ii  linux-modules-2.6.26-1-xen-amd64    2.6.26-10
ii  bash                                3.2-4

this is a Xen dom0

Message #170 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Frank Gevaerts <frank@gevaerts.be>

To: Debian Bug Tracking System <476519@bugs.debian.org>

Subject: 476519 seems to be indeed SMP related

Date: Wed, 06 May 2009 19:37:05 +0200

Package: bash
Severity: normal

I've seen this bug on a 1 CPU lenny xen domU, with both dom0 and domU running the standard lenny 2.6.26 kernel on a dual-quadcore system (E5310 CPUs). It goes away when I give the guest 2 CPUs instead of 1.

Also, you probably already know this, but this seems to be the same bug as http://bugs.gentoo.org/show_bug.cgi?id=232630 and https://bugs.launchpad.net/ubuntu/+source/sudo/+bug/224802.

Message #175 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Heinrich Schuchardt <heinrich.schuchardt@gmx.de>

To: 476519@bugs.debian.org

Subject: Reproduced in SID chroot - depends on /home/user/.bashrc

Date: Sat, 06 Jun 2009 14:49:34 +0200

I am using a SID chroot on a Lenny system.

In the chroot I experienced the problem that 'su user'  would end after 
any keystroke and return to the root environment.

The problem does not occur with shell /bin/sh but only with /bin/bash as 
user shell.

The problem disappeared after
rm /home/user/.bashrc

I boiled down the users .bashrc until it contained only the following 
two lines:
[ -x /usr/bin/lesspipe ] && eval "$(lesspipe)"
PROMPT_COMMAND='echo -n ">"'

If any of the above lines is removed the error disappears.

/usr/bin/lesspipe returns:
export LESSOPEN="| /usr/bin/lesspipe %s";
export LESSCLOSE="/usr/bin/lesspipe %s %s";

Best regards

Xypron

Message #180 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stefan Kaltenbrunner <stefan@kaltenbrunner.cc>

To: 476519@bugs.debian.org

Subject: SMP and or/Memory related

Date: Tue, 28 Jul 2009 19:05:57 +0200

We just hit that very same issue on Host running Lenny(inside an VMware 
ESX4 Host).
The exact conditions for this to trigger here are:

* exactly ONE cpu/core configured on the host
* exactly 16GB RAM (using 8, 14 or 18GB does not cause the issue to appear)
* bash as the shell


removing one of the above variables cures the issue here so I would 
argue that this actually might be a kernel bug

Stefan

Message #185 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Rolf Luettecke <Rolf.Luettecke@michael-telecom.de>

To: 476519@bugs.debian.org

Subject: su - nonrootuser: Often logged out on first keypress

Date: Wed, 29 Jul 2009 12:10:43 +0200

Same issue here:

Linux 2.6.26-2-amd64 #1 SMP Fri Mar 27 04:02:59 UTC 2009 x86_64 GNU/Linux
GNU bash, version 3.2.39(1)-release (x86_64-pc-linux-gnu)

i.e.:
su - nobody
su - postgres

logs me out really often on first key pressed.

su -
seems to work.


Cheers
 -Rolf

Message #190 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Marian Such <toxygen1@gmail.com>

To: 476519@bugs.debian.org

Subject: any progress?

Date: Thu, 7 Jan 2010 14:02:39 +0100

Hi,
it has been 1.5 years since the bug was reported.
As I'm hitting the bug everyday, I would like to ask if there was any  
progress.

regards
marian

Message #195 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Stig Manning <stig@sdm.co.nz>

To: 476519@bugs.debian.org

Subject: Still an issue.

Date: Fri, 27 Aug 2010 10:19:33 +1000

Now 2 years since this was reported.

Experiencing this infrequently on a number of WMWare hosts, single CPU, 
2GB Ram.

Linux evo7-dvmh-web-05 2.6.26-2-686 #1 SMP Wed Feb 10 08:59:21 UTC 2010 
i686 GNU/Linux

Cheers,
Stig

Message #200 received at 476519@bugs.debian.org (full text, mbox, reply):

From: Joern Merkel <joern.merkel@luka.de>

To: 476519@bugs.debian.org

Subject: happen on debian 5, too

Date: Thu, 14 Oct 2010 11:47:37 +0200

Hi,

I got the same Problem on a freshly installed Debian 5-box.

# uname -a
Linux mail3 2.6.26-2-amd64 #1 SMP Thu Sep 16 15:56:38 UTC 2010 x86_64 GNU/Linux

trying:

# su cyrus
cyrus@mail3:/tmp$ dexit

however, if I tried to strace it, it won't happen:

# strace su cyrus
....
rt_sigprocmask(SIG_BLOCK, ~[RTMIN RT_1], NULL, 8) = 0
rt_sigaction(SIGTERM, {0x402420, [], SA_RESTORER, 0x7fca4965ff60}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [ALRM TERM], NULL, 8) = 0
wait4(-1,
(now typing 'd's an press return)
dddddddddddddd
bash: dddddddddddddd: command not found
cyrus@mail3:/tmp$ exit
[{WIFEXITED(s) && WEXITSTATUS(s) == 127}], WSTOPPED, NULL) = 13167
getuid()                                = 108
gettimeofday({1287048698, 560056}, NULL) = 0
stat("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2309, ...}) = 0
socket(PF_FILE, SOCK_DGRAM, 0)          = 3
fcntl(3, F_SETFD, FD_CLOEXEC)           = 0
connect(3, {sa_family=AF_FILE, path="/dev/log"...}, 110) = 0
sendto(3, "<86>Oct 14 11:31:38 su[13166]: pa"..., 82, MSG_NOSIGNAL, NULL, 0) = 82
munmap(0x7fca489f2000, 2099928)         = 0
munmap(0x7fca485d3000, 2107528)         = 0
munmap(0x7fca483d1000, 2104616)         = 0
munmap(0x7fca481b8000, 2197472)         = 0
munmap(0x7fca487d6000, 2209368)         = 0
munmap(0x7fca47f80000, 2322880)         = 0
exit_group(127)                         = ?

I've found the same bugreport for gentoo:

http://bugs.gentoo.org/show_bug.cgi?id=232630

they mentioned, it may be some kind of timing issue, but there is no fix for it.

I installed some other boxes from the same repository (also Debian 5) and there
is no such behaviour.


kind regards

jm

kind regards

jm

Message #205 received at 476519@bugs.debian.org (full text, mbox, reply):

From: "Elizabeth Liu" <donald341roger@gmail.com>

To: "476519" <476519@bugs.debian.org>

Subject: Geschäftsantwort

Date: Wed, 20 Oct 2021 05:14:11 +0200

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Elizabeth Liu

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Message #208 received at 476519-submitter@bugs.debian.org (full text, mbox, reply):

From: "Elizabeth Liu" <donald341roger@gmail.com>

To: "476519-submitter" <476519-submitter@bugs.debian.org>

Subject: Geschäftsantwort

Date: Wed, 20 Oct 2021 05:14:15 +0200

[Message part 1 (text/plain, inline)]

Hallo, ich bin Frau Elizabeth Liu, wenn Sie als vor der Covid-19-Epidemie geschützt markiert wurden, meine Gebete mit Ihnen. Ich möchte Ihnen ein Geschäft im Wert von $7,400,000.00 USD anbieten. Wenn Sie interessiert sind, kontaktieren Sie mich privat. E-Mail: elizabethliu@winghangbnk.com

Elizabeth Liu

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