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Date:   Thu, 21 Apr 2022 19:29:13 +0200
From:   Artem Savkov <asavkov@redhat.com>
To:     Daniel Borkmann <daniel@iogearbox.net>
Cc:     Alan Maguire <alan.maguire@oracle.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>, bpf@vger.kernel.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org
Subject: Re: [PATCH bpf-next] selftests/bpf: fix prog_tests/uprobe_autoattach
 compilation error
Message-ID: <YmGUaXfBywiSQ+Sy@sparkplug.usersys.redhat.com>
References: <20220421132317.1583867-1-asavkov@redhat.com>
 <e5919342-0697-65f0-063f-4941e74fe1ca@iogearbox.net>
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On Thu, Apr 21, 2022 at 06:53:22PM +0200, Daniel Borkmann wrote:
> On 4/21/22 3:23 PM, Artem Savkov wrote:
> > I am getting the following compilation error for prog_tests/uprobe_autoattach.c
> > 
> > tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c: In function ‘test_uprobe_autoattach’:
> > ./test_progs.h:209:26: error: pointer ‘mem’ may be used after ‘free’ [-Werror=use-after-free]
> > 
> > mem variable is now used in one of the asserts so it shouldn't be freed right
> > away. Move free(mem) after the assert block.
> 
> Looks good, but I rephrased this a bit to avoid confusion. It's false positive given we
> only compare the addresses but don't deref mem, which the compiler might not be able to
> follow in this case.
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=6a12b8e20d7e72386594a9dbe7bf2d7fae3b3aa6

Right. Thank you for fixing up the commit message.

-- 
 Artem