RE: [PATCH v2] selftests/lkdtm: Use /bin/sh not $SHELL

From: David Laight
Date: Thu Jun 24 2021 - 03:21:22 EST


From: Kees Cook
> Sent: 23 June 2021 23:47
>
> On Wed, Jun 23, 2021 at 04:27:47PM +0000, David Laight wrote:
...
> > You can probably even do:
> >
> > echo "$test" | /bin/sh -c cat >$TRIGGER || true
> >
> > (moving the redirect to the outer shell).
>
> Actually, it looks like the "write" is already happening in the exec'd
> process, so this can just be:
>
> echo "$test" | cat >$TRIGGER || true
>
> But it still can't be:
>
> echo "$test" >$TRIGGER
>
> which is what I had over-engineered a solution to. :)

That one fails because echo is the shell builtin.
But:
/bin/echo "$test" >$TRIGGER
should be fine.

Quite where the original came from I not sure I want to find out.

David

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