Re: udp.sendmsg

[David Smith <dsmith at redhat dot com>]

On 08/25/2016 11:18 AM, webman@manfbraun.de wrote:
> Hello !
> 
> Many thanks for your answer!
> Sometimes, writing "it's not working" reactivates some areas
> in the own brain, do dig deeper ...
> What ist failing for me, is my modified version of the original
> script. I run the original and no errors at all ... ;-)
> 
> So, here is MY version - with my little newbies thinking about
> this type of scripts ;-)
> 
> =======================
> probe begin { printf("Monitoring use of port 53\n") }
> probe end { printf("Stopped.\n") }
> 
> probe udp.sendmsg {
>         if ( dport == 53 ) {
>                 task = pid2task(pid());
>                 printf(
>                         "UDP53 %5d.%6d %15s %d(%s/%s) %d(%s)\n",
>                         gettimeofday_s(),
>                         gettimeofday_ms(),
>                         daddr,
>                         pid(),
>                         task_execname(task),
>                         execname(),
>                         ppid(),
>                         pexecname()
>                         )
>         }
> }

OK, here's a couple of things about your script.

  task = pid2task(pid())

is the same thing as:

  task = task_current()

Plus, since task is the current task, task_execname(task) and execname()
are always going to return the same string.

So, at that point you really don't need your 'task' variable.

If you are still getting that kernel_string copy fault error, you'll
need to delete/replace one function call at a time so that we can narrow
down which function is causing the fault.

-- 
David Smith
dsmith@redhat.com
Red Hat
http://www.redhat.com
256.217.0141 (direct)
256.837.0057 (fax)