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From: David Gow <davidgow@google.com>
Date: Fri, 22 Dec 2023 16:39:14 +0800
Message-ID: <CABVgOSnoJEZOCdPBVqBKS=sEXeeq_6_+G4PPodY0HWJ3A7yA+A@mail.gmail.com>
Subject: Re: [PATCH] kunit: Protect string comparisons against NULL
To: Richard Fitzgerald <rf@opensource.cirrus.com>
Cc: brendan.higgins@linux.dev, rmoar@google.com, 
	linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com, 
	linux-kernel@vger.kernel.org, patches@opensource.cirrus.com
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On Wed, 20 Dec 2023 at 23:52, Richard Fitzgerald
<rf@opensource.cirrus.com> wrote:
>
> Add NULL checks to KUNIT_BINARY_STR_ASSERTION() so that it will fail
> cleanly if either pointer is NULL, instead of causing a NULL pointer
> dereference in the strcmp().
>
> A test failure could be that a string is unexpectedly NULL. This could
> be trapped by KUNIT_ASSERT_NOT_NULL() but that would terminate the test
> at that point. It's preferable that the KUNIT_EXPECT_STR*() macros can
> handle NULL pointers as a failure.
>
> Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
> ---

I think this is the right thing to do. There's possibly an argument
that this should succeed if both are NULL, but I prefer it this way.

Reviewed-by: David Gow <davidgow@google.com>

Cheers,
-- David

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