On Wed, Aug 26, 2020 at 2:30 PM 'Andrey Konovalov' via kasan-dev <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > > On Tue, Aug 25, 2020 at 10:26 AM 'Marco Elver' via kasan-dev > <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > > > > On Tue, 25 Aug 2020 at 03:57, Walter Wu <walter-zh.wu@xxxxxxxxxxxx> 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 > > > [3]https://bugzilla.kernel.org/show_bug.cgi?id=198437 > > > > > > Walter Wu (6): > > > timer: kasan: record timer stack > > > workqueue: kasan: record workqueue stack > > > kasan: print timer and workqueue stack > > > lib/test_kasan.c: add timer test case > > > lib/test_kasan.c: add workqueue test case > > > kasan: update documentation for generic kasan > > > > Acked-by: Marco Elver <elver@xxxxxxxxxx> > > Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Thanks! The UAF reports with RCU stacks that I see now are just 🔥🔥🔥 > > > --- > > > > > > Changes since v2: > > > - modify kasan document to be more readable. > > > Thanks for Marco suggestion. > > > > > > Changes since v1: > > > - Thanks for Marco and Thomas suggestion. > > > - Remove unnecessary code and fix commit log > > > - reuse kasan_record_aux_stack() and aux_stack > > > to record timer and workqueue stack. > > > - change the aux stack title for common name. > > > > > > --- > > > > > > Documentation/dev-tools/kasan.rst | 4 ++-- > > > kernel/time/timer.c | 3 +++ > > > kernel/workqueue.c | 3 +++ > > > lib/test_kasan.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > mm/kasan/report.c | 4 ++-- > > > 5 files changed, 64 insertions(+), 4 deletions(-) > > > > > > -- > > > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > > > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20200825015654.27781-1-walter-zh.wu%40mediatek.com. > > > > -- > > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/CANpmjNOvj%2B%3Dv7VDVDXpsUNZ9o0%2BKoJVJs0MjLhwr0XpYcYQZ5g%40mail.gmail.com. > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/CAAeHK%2ByVShDPCxVKDsO_5SwoM2ZG7x7byUJ74PtB7ekY61L2YQ%40mail.gmail.com.
