RE: [PATCH v2] tracing: Add test for user space strings when filtering on string pointers

From: David Laight
Date: Fri Jan 14 2022 - 04:35:13 EST


From: Steven Rostedt
> Sent: 14 January 2022 02:15
>
> On Thu, 13 Jan 2022 16:51:15 -0500
> Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>
> > We could add something later. As it is currently the merge window, and this
> > is a real bug, I'm going to just leave it as is, and we can work to fix the
> > other archs later. I need to get a pull request ready by tomorrow.
>
> Actually I got this working, and looks like a reasonable answer to the
> problem. It basically requires that the user specify that the pointer
> points into user space for the kernel to read it.

Certainly look better.

I'm not sure about the difference between the _inatomic() and _nocheck()
user access functions though.

David

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