Re: [PATCH] i3c: master: svc: Fix use after free vulnerability in svc_i3c_master Driver Due to Race Condition

[Kaixin Wang]

在 2024-09-12 14:57:09，"Miquel Raynal" <miquel.raynal@xxxxxxxxxxx> 写道：
>Hi,
>
>Frank.li@xxxxxxx wrote on Wed, 11 Sep 2024 11:24:57 -0400:
>
>> On Wed, Sep 11, 2024 at 11:01:35PM +0800, Kaixin Wang wrote:
>> > In the svc_i3c_master_probe function, &master->hj_work is bound with
>> > svc_i3c_master_hj_work, &master->ibi_work is bound with
>> > svc_i3c_master_ibi_work. And svc_i3c_master_ibi_work  can start the
>> > hj_work, svc_i3c_master_irq_handler can start the ibi_work.
>> >
>> > If we remove the module which will call svc_i3c_master_remove to
>> > make cleanup, it will free master->base through i3c_master_unregister
>> > while the work mentioned above will be used. The sequence of operations
>> > that may lead to a UAF bug is as follows:
>> >
>> > CPU0                                         CPU1
>> >
>> >                                     | svc_i3c_master_hj_work
>> > svc_i3c_master_remove               |
>> > i3c_master_unregister(&master->base)|
>> > device_unregister(&master->dev)     |
>> > device_release                      |
>> > //free master->base                 |
>> >                                     | i3c_master_do_daa(&master->base)
>> >                                     | //use master->base
>> >
>> > Fix it by ensuring that the work is canceled before proceeding with the
>> > cleanup in svc_i3c_master_remove.
>> >
>> > Signed-off-by: Kaixin Wang <kxwang23@xxxxxxxxxxxxxx>
>> > ---  
>> 
>> Please add fixes tag and cc stable.
>
>Yes indeed. Otherwise looks good to me once this fixed.
>
>Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
>
>Thanks,
>Miquèl
>

Thanks for the review!

Best regards,
Kaixin Wang