SIGEPIPE after update to 8.1-RC2
Kostik Belousov
kostikbel at gmail.com
Wed Jul 28 20:43:14 UTC 2010
On Sun, Jul 25, 2010 at 01:48:16PM +0200, Jilles Tjoelker wrote:
> On Sun, Jul 18, 2010 at 12:20:33PM +1000, Sean wrote:
> > I'm getting the same thing; what shell are you using? I changed my shell
> > on one machine from /bin/tcsh to /usr/local/bin/bash and problem
> > disappeared.
>
> That this workaround helps confirms that masked/ignored SIGPIPE is the
> problem. From a few shells I have tried, bash and zsh reset SIGPIPE to
> caught or default even if it was ignored (only in interactive mode,
> however), while tcsh, sh, mksh and ksh93 leave it ignored.
>
> The underlying problem is the program that is passing the ignored/masked
> signal to child processes. Please check if the problem occurs with
> various ways to log in (text console, ssh, xterm, etc). Things like PAM
> modules may also cause problems here.
>
> For example, sshd sets SIGPIPE to ignored, but resets it back to default
> before starting a child process, so assuming I read the code correctly
> it does not cause problems.
Hm.
pooma% cat
...
In the other shell,
pooma% ps auxww | grep cat
kostik 41346 0.0 0.0 5824 1084 2 I+ 11:34PM 0:00.00 cat
pooma% procstat -i 41346 | grep PIPE
41346 cat PIPE ---
pooma% sudo cat
...
and
pooma% ps auxww | grep cat
root 41360 0.0 0.0 5824 1084 2 S+ 11:36PM 0:00.01 cat
pooma% procstat -i 41366 | grep PIPE
41366 cat PIPE ---
And now
oma% sudo -k cat ~
Password:
...
and
pooma% ps auxww | grep cat
root 41387 0.0 0.0 5824 1084 2 S+ 11:39PM 0:00.01 cat
pooma% procstat -i 41387 | grep PIPE
41387 cat PIPE -I-
This would describe both the observed behaviour and the reason why
I was unable to repeat it after the first run.
sudo changelog has a promising entry from 2010-06-09, but I definitely
not going to read sudo code. security/sudo maintainer Cc:ed.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-stable/attachments/20100728/2cf039e5/attachment.pgp
More information about the freebsd-stable
mailing list