Messages in this thread | ![/](/images/icornerl.gif) | | From | Zheng Hacker <> | Date | Wed, 26 Apr 2023 01:18:12 +0800 | Subject | Re: [PATCH] HID: intel-ish-hid: pci-ish: Fix use after free bug in ish_remove due to race condition |
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srinivas pandruvada <srinivas.pandruvada@linux.intel.com> 于2023年4月25日周二 23:55写道: > > On Thu, 2023-04-13 at 01:14 +0800, Zheng Wang wrote: > > In ish_probe, it calls ish_dev_init to init the device. In this > > function, > > ishtp_device_init is called and &dev->bh_hbm_work is bound with > > bh_hbm_work_fn. recv_hbm may be called to start the timer work. > > > > If we remove the module which will call ish_remove to make cleanup, > > there may be an unfinished work. The possible sequence is as follows: > > > > Fix it by canceling the work before cleanup in > > ishtp_bus_remove_all_clients > > > > CPU0 CPUc1 > > > > |bh_hbm_work_fn > > ish_remove | > > ishtp_bus_remove_all_clients | > > kfree(ishtp_dev->fw_clients); | > > | > > |&dev->fw_clients[...] > > | //use > > > > Fixes: 3703f53b99e4 ("HID: intel_ish-hid: ISH Transport layer") > > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> > > It is a extremely rare case, so it is OK to not mark for stable.
Got it, thanks!
Best regards, Zheng
> > > --- > > drivers/hid/intel-ish-hid/ishtp/bus.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/hid/intel-ish-hid/ishtp/bus.c > > b/drivers/hid/intel-ish-hid/ishtp/bus.c > > index 81385ab37fa9..ada7cd08dbeb 100644 > > --- a/drivers/hid/intel-ish-hid/ishtp/bus.c > > +++ b/drivers/hid/intel-ish-hid/ishtp/bus.c > > @@ -744,6 +744,7 @@ void ishtp_bus_remove_all_clients(struct > > ishtp_device *ishtp_dev, > > */ > > } > > spin_unlock_irqrestore(&ishtp_dev->cl_list_lock, flags); > > + cancel_work_sync(&ishtp_dev->bh_hbm_work); > > > > /* Release DMA buffers for client messages */ > > ishtp_cl_free_dma_buf(ishtp_dev); >
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