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To:     Walter Wu <walter-zh.wu@mediatek.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        John Stultz <john.stultz@linaro.org>,
        Stephen Boyd <sboyd@kernel.org>, Tejun Heo <tj@kernel.org>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Marco Elver <elver@google.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Matthias Brugger <matthias.bgg@gmail.com>
Cc:     kasan-dev@googlegroups.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        wsd_upstream <wsd_upstream@mediatek.com>,
        linux-mediatek@lists.infradead.org,
        Walter Wu <walter-zh.wu@mediatek.com>
Subject: Re: [PATCH v4 0/6] kasan: add workqueue and timer stack for generic KASAN
In-Reply-To: <20200924040152.30851-1-walter-zh.wu@mediatek.com>
References: <20200924040152.30851-1-walter-zh.wu@mediatek.com>
Date:   Wed, 30 Sep 2020 17:29:40 +0200
Message-ID: <87h7rfi8pn.fsf@nanos.tec.linutronix.de>
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On Thu, Sep 24 2020 at 12:01, Walter Wu wrote:
> Syzbot reports many UAF issues for workqueue or timer, see [1] and [2].
> In some of these access/allocation happened in process_one_work(),
> we see the free stack is useless in KASAN report, it doesn't help
> programmers to solve UAF on workqueue. The same may stand for times.
>
> This patchset improves KASAN reports by making them to have workqueue
> queueing stack and timer stack information. It is useful for programmers
> to solve use-after-free or double-free memory issue.
>
> Generic KASAN also records the last two workqueue and timer stacks and
> prints them in KASAN report. It is only suitable for generic KASAN.
>
> [1]https://groups.google.com/g/syzkaller-bugs/search?q=%22use-after-free%22+process_one_work
> [2]https://groups.google.com/g/syzkaller-bugs/search?q=%22use-after-free%22%20expire_timers

How are these links useful for people who do not have a gurgle account?