linux-kernel - Re: [PATCH 3/4] binder: fix freeze UAF in binder_release

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAH5fLggAoKssv+nmg54ibsdTtPF_kxU=WGHK6zQDRxaSd8dpdw@mail.gmail.com>
Date: Wed, 25 Sep 2024 10:03:55 +0200
From: Alice Ryhl <aliceryhl@...gle.com>
To: Carlos Llamas <cmllamas@...gle.com>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Arve Hjønnevåg <arve@...roid.com>, 
	Todd Kjos <tkjos@...roid.com>, Martijn Coenen <maco@...roid.com>, 
	Joel Fernandes <joel@...lfernandes.org>, Christian Brauner <brauner@...nel.org>, 
	Suren Baghdasaryan <surenb@...gle.com>, Yu-Ting Tseng <yutingtseng@...gle.com>, linux-kernel@...r.kernel.org, 
	kernel-team@...roid.com, stable@...r.kernel.org
Subject: Re: [PATCH 3/4] binder: fix freeze UAF in binder_release_work()

On Tue, Sep 24, 2024 at 8:44 PM Carlos Llamas <cmllamas@...gle.com> wrote:
>
> When a binder reference is cleaned up, any freeze work queued in the
> associated process should also be removed. Otherwise, the reference is
> freed while its ref->freeze.work is still queued in proc->work leading
> to a use-after-free issue as shown by the following KASAN report:
>
>   ==================================================================
>   BUG: KASAN: slab-use-after-free in binder_release_work+0x398/0x3d0
>   Read of size 8 at addr ffff31600ee91488 by task kworker/5:1/211
>
>   CPU: 5 UID: 0 PID: 211 Comm: kworker/5:1 Not tainted 6.11.0-rc7-00382-gfc6c92196396 #22
>   Hardware name: linux,dummy-virt (DT)
>   Workqueue: events binder_deferred_func
>   Call trace:
>    binder_release_work+0x398/0x3d0
>    binder_deferred_func+0xb60/0x109c
>    process_one_work+0x51c/0xbd4
>    worker_thread+0x608/0xee8
>
>   Allocated by task 703:
>    __kmalloc_cache_noprof+0x130/0x280
>    binder_thread_write+0xdb4/0x42a0
>    binder_ioctl+0x18f0/0x25ac
>    __arm64_sys_ioctl+0x124/0x190
>    invoke_syscall+0x6c/0x254
>
>   Freed by task 211:
>    kfree+0xc4/0x230
>    binder_deferred_func+0xae8/0x109c
>    process_one_work+0x51c/0xbd4
>    worker_thread+0x608/0xee8
>   ==================================================================
>
> This commit fixes the issue by ensuring any queued freeze work is removed
> when cleaning up a binder reference.
>
> Fixes: d579b04a52a1 ("binder: frozen notification")
> Cc: stable@...r.kernel.org
> Signed-off-by: Carlos Llamas <cmllamas@...gle.com>

Reviewed-by: Alice Ryhl <aliceryhl@...gle.com>