Re: [perf] more perf_fuzzer memory corruption

From: Steven Rostedt
Date: Tue Apr 29 2014 - 15:26:44 EST


On Tue, 29 Apr 2014 14:21:56 -0400 (EDT)
Vince Weaver <vincent.weaver@xxxxxxxxx> wrote:

> Also trace-cmd is a pain to use. Any suggested events I should trace
> beyond the obvious?
>
> Part of the problem is that despite what the documentation says it doesn't
> look like you can combine the "-P pid" and "-c" children option, which
> makes debugging a forking problem like this a lot harder to trace.

Yeah, I need kernel assistance to fix some of that.

>
> It's sort of possible to get around that with a really complicated -F ""
> command line that does sudo back to me (don't want to fuzz as root) and
> such, but still awkward.

I'll try to write up a patch that lets you use -P with -c. But due to
the (crappy) implementation with ptrace, trace-cmd needs to be a parent
of task.

In the mean time, you could run this as root:

trace-cmd record -p function -F -c su non-root-user fuzz


-- Steve
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/