SIGCHLD may be inherited blocked

[Nicolas Williams]

On Fri, Jun 07, 2002 at 03:40:28PM -0500, Chris Adams wrote:
> Funny; I just ran into a case of sshd running with SIGALRM blocked on
> Linux (caused problems because I restarted sendmail from an ssh login,
> and it would never time out connections because SIGALRM was always
> blocked).
> 
> Would it be a problem for sshd to clear the blocked signals at start?
> Is there a valid case for it to inherit blocked signals?

Doing a quick search I see that POSIX requires signal masks to be
inherited across exec*(). It seems that there may be or have been some
question as to whether its the signal-blocking-during-delivery mask or
the signal block mask that should be inherited.

I think sshd should, in fact, clear at least SIGCHLD's blocking, and
maybe [all] others as well. But then, sshd does not bother closing
extraneous file descriptors (nor do I think it should), so how best to
put the argument that sshd should initialize the signal blocking masks?

Cheers,

Nico
-- 
-DISCLAIMER: an automatically appended disclaimer may follow. By posting-
-to a public e-mail mailing list I hereby grant permission to distribute-
-and copy this message.-

Visit our website at http://www.ubswarburg.com

This message contains confidential information and is intended only 
for the individual named.  If you are not the named addressee you 
should not disseminate, distribute or copy this e-mail.  Please 
notify the sender immediately by e-mail if you have received this 
e-mail by mistake and delete this e-mail from your system.

E-mail transmission cannot be guaranteed to be secure or error-free 
as information could be intercepted, corrupted, lost, destroyed, 
arrive late or incomplete, or contain viruses.  The sender therefore 
does not accept liability for any errors or omissions in the contents 
of this message which arise as a result of e-mail transmission.  If 
verification is required please request a hard-copy version.  This 
message is provided for informational purposes and should not be 
construed as a solicitation or offer to buy or sell any securities or 
related financial instruments.