On 25/10/10 15:57, Paul Ortyl wrote:

> I have filed an Ubuntu bug after being unable to use --db-attach=yes feature
> of valgrind.
> https://bugs.launchpad.net/bugs/665850
>
> It looks like this feature has been destroyed "by design":
> https://wiki.ubuntu.com/Security/Features#ptrace
> https://wiki.ubuntu.com/SecurityTeam/Roadmap/KernelHardening#ptrace%20Protection
>
> This new hardened behaviour can be deactivated by modifying
> /proc/sys/kernel/yama/ptrace_scope
> which is then global and not really pretty solution.

As I read that, you can still ptrace your own descendants (which is what 
valgrind does) just not other processes owned by the same user.

So I think the diagnosis you were given may be wrong.

That said, the db-attach feature is very fragile and often fails and I 
would generally advise only trying to use it as a last resort - it is 
normally quite possible to find and fix problems without it.

Tom

-- 
Tom Hughes ([email protected])
http://compton.nu/

------------------------------------------------------------------------------
Nokia and AT&T present the 2010 Calling All Innovators-North America contest
Create new apps & games for the Nokia N8 for consumers in  U.S. and Canada
$10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing
Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store 
http://p.sf.net/sfu/nokia-dev2dev
_______________________________________________
Valgrind-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/valgrind-users

Reply via email to