[Nagiosplug-devel] [ nagiosplug-Patches-1455619 ] check_procs segfaults with zombies

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Patches item #1455619, was opened at 2006-03-21 20:03
Message generated for change (Comment added) made by tonvoon
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Category: Bugfix
Group: None
>Status: Pending
Resolution: None
Priority: 5
Submitted By: gerhard lausser (lausser)
>Assigned to: Ton Voon (tonvoon)
Summary: check_procs segfaults with zombies

Initial Comment:
Hi,
under solaris, ps produces output like this for 
zombie processes:
Z 55618 28898 15263    0    0  0.0 

The statement 
cols = sscanf (input_line, PS_FORMAT, PS_VARLIST);
which is actually this one:
...sscanf (input_line, "%s %d %d %d %d %d %f %s%n", 
procstat,&procuid,&procpid,&procpid,&procvsz,&procrss,
&procpcpu,procprog,&pos);

does not fill the pos variable with a value because 
there is no match for the last %s. pos keeps the 
value it got when the last time a non-zombie process 
was found.

pos points to the arguments following procprog which 
is senseless in this case anyway. but later it is 
used to initialize the procargs array.
asprintf (&procargs, "%s", input_line + pos);
In the case of a zombie pos has a value related to 
the last input_line but not the current one, so an 
illegal byte beyond the strings end may be accessed.

I made a patch which takes this into account.

Greetings from Munich,
Gerhard


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>Comment By: Ton Voon (tonvoon)
Date: 2006-03-22 13:15

Message:
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user_id=664364

Gerhard,

Thanks for the patch. For the upcoming 1.4.3 release, Solaris processes will 
be read differently. A new executable, pst, will be created which will return 
the equivalent ps output. Please can you try this and see if it fixes your 
zombie issues.

If not, I'll be happy to accept a patch against that.

Please try the snapshot at http://nagiosplug.sourceforge.net/snapshot/

Ton

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You can respond by visiting: 
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