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From:   Jann Horn <jannh@google.com>
Date:   Tue, 1 Feb 2022 19:35:12 +0100
Message-ID: <CAG48ez1O2Nt2eiJ6ZbV8q+XSsg+Co4GhdaLxi-aNF4PRm5R+mg@mail.gmail.com>
Subject: Re: [PATCH 3/5] coredump: Remove the WARN_ON in dump_vma_snapshot
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Matthew Wilcox <willy@infradead.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Denys Vlasenko <vda.linux@googlemail.com>,
        Kees Cook <keescook@chromium.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Liam R . Howlett" <liam.howlett@oracle.com>
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On Mon, Jan 31, 2022 at 7:46 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> The condition is impossible and to the best of my knowledge has never
> triggered.
>
> We are in deep trouble if that conditions happens and we walk past
> the end of our allocated array.
>
> So delete the WARN_ON and the code that makes it look like the kernel
> can handle the case of walking past the end of it's vma_meta array.
>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Reviewed-by: Jann Horn <jannh@google.com>