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Date:   Tue, 10 Jan 2023 14:39:04 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Seth Jenkins <sethjenkins@google.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Benjamin LaHaise <bcrl@kvack.org>,
        linux-fsdevel@vger.kernel.org, linux-aio@kvack.org,
        linux-kernel@vger.kernel.org, Jann Horn <jannh@google.com>,
        Pavel Emelyanov <xemul@parallels.com>, stable@vger.kernel.org
Subject: Re: [PATCH] aio: fix mremap after fork null-deref
Message-Id: <20230110143904.8f8c6c0f80aa01c938326446@linux-foundation.org>
In-Reply-To: <20221104212519.538108-1-sethjenkins@google.com>
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On Fri,  4 Nov 2022 17:25:19 -0400 Seth Jenkins <sethjenkins@google.com> wrote:

> Commit e4a0d3e720e7 ("aio: Make it possible to remap aio ring") introduced
> a null-deref if mremap is called on an old aio mapping after fork as
> mm->ioctx_table will be set to NULL.
> 

Is this a theoretical thing, or has this oops actually been observed?