Thread: pgadmin3 segfaults on leaving context menu

Hello all,

pgAdmin consistently crashes with a segmentation fault for me after
leaving the right-click menu in the object browser. Either selecting
an option or clicking elsewhere to close it will cause a crash.

pgAdmin version: 1.20.0
wxgtk version: 2.8.12.1-2
gtk2 version: 2.24.27-1
OS: Arch Linux 3.19.3-3-ARCH

Both the OS-provided package and a self-compiled binary exhibit the
same behaviour.

I apologize if this issue has already been reported/fixed - there were
a few threads in the archive that looked similar, but I don't know
enough about pgAdmin to know if they're the same problem.

I hope this helps. Keep up the good work.

Kind regards,
Wander Nauta

Hello all,

I did some more digging and it seems frmMain::OnSelRightClick is
trying to unlock a mutex it doesn't own, which can result in undefined
behaviour in POSIX.

I've attached a patch that moves the unlock inside the if where the
mutex is locked. This seems to fix the crash, at least on my end, but
I couldn't say if it affects thread safety at all.

Again, I hope this helps.

Kind regards,
Wander Nauta

Ashesh; can you look at this please?

Thanks.

On Sun, Apr 19, 2015 at 3:44 PM, Wander Nauta <info@wandernauta.nl> wrote:
> Hello all,
>
> I did some more digging and it seems frmMain::OnSelRightClick is
> trying to unlock a mutex it doesn't own, which can result in undefined
> behaviour in POSIX.
>
> I've attached a patch that moves the unlock inside the if where the
> mutex is locked. This seems to fix the crash, at least on my end, but
> I couldn't say if it affects thread safety at all.
>
> Again, I hope this helps.
>
> Kind regards,
> Wander Nauta
>
>
> --
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> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgadmin-support
>



-- 
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

EnterpriseDB UK: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Hello Ashesh,

With that patch applied, pgadmin3 hangs the moment I choose an item
from the context menu. It doesn't crash or hang when I exit the menu
by clicking outside it, but clicking inside it causes the application
to stop responding.

Looking at a backtrace (attached), it seems that `onSelRightClick`
grabs the mutex, then calls `doPopup`. However, because doPopup
(indirectly) causes execSelChange, that method is now being called
with the mutex held.

Regards,
Wander


On Mon, Apr 20, 2015 at 11:21 AM, Ashesh Vashi
<ashesh.vashi@enterprisedb.com> wrote:
> Hi Wander Nauta,
>
> As per comment above the mutex lock, we need to hold the lock until, the
> context menu is getting popped up correctly.
> I've modified the code accordingly.
>
> Can you please test the attached patch?
>
> --
>
> Thanks & Regards,
>
> Ashesh Vashi
> EnterpriseDB INDIA: Enterprise PostgreSQL Company
>
>
> http://www.linkedin.com/in/asheshvashi
>
>
> On Mon, Apr 20, 2015 at 1:21 PM, Dave Page <dpage@pgadmin.org> wrote:
>>
>> Ashesh; can you look at this please?
>>
>> Thanks.
>>
>> On Sun, Apr 19, 2015 at 3:44 PM, Wander Nauta <info@wandernauta.nl> wrote:
>> > Hello all,
>> >
>> > I did some more digging and it seems frmMain::OnSelRightClick is
>> > trying to unlock a mutex it doesn't own, which can result in undefined
>> > behaviour in POSIX.
>> >
>> > I've attached a patch that moves the unlock inside the if where the
>> > mutex is locked. This seems to fix the crash, at least on my end, but
>> > I couldn't say if it affects thread safety at all.
>> >
>> > Again, I hope this helps.
>> >
>> > Kind regards,
>> > Wander Nauta
>> >
>> >
>> > --
>> > Sent via pgadmin-support mailing list (pgadmin-support@postgresql.org)
>> > To make changes to your subscription:
>> > http://www.postgresql.org/mailpref/pgadmin-support
>> >
>>
>>
>>
>> --
>> Dave Page
>> Blog: http://pgsnake.blogspot.com
>> Twitter: @pgsnake
>>
>> EnterpriseDB UK: http://www.enterprisedb.com
>> The Enterprise PostgreSQL Company
>
>