Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
From:   Dongliang Mu <mudongliangabcd@gmail.com>
Date:   Tue, 21 Jun 2022 22:36:04 +0800
Message-ID: <CAD-N9QVVKUDFKMSxUc-smcz0B_7PrjN3DPku+cDM3ZKDn0XLBA@mail.gmail.com>
Subject: Unitialized Variable and Null Pointer Dereference bug in gb_bootrom_get_firmware
To:     vireshk@kernel.org, Johan Hovold <johan@kernel.org>,
        elder@kernel.org, Greg KH <gregkh@linuxfoundation.org>
Cc:     greybus-dev@lists.linaro.org, linux-staging@lists.linux.dev,
        linux-kernel <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi maintainers,

I would like to send one bug report.

In gb_bootrom_get_firmware, if the first branch is satisfied, it will
go to queue_work, leading to the dereference of uninitialized const
variable "fw". If the second branch is satisfied, it will go to unlock
with fw as NULL pointer, leading to a NULL Pointer Dereference.

The Fixes commit should be [1], introducing the dereference of "fw" in
the error handling code.

I am not sure how to fix this bug. Any comment on removing the
dereference of fw?

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a4293e1d4e6416477976ee3bd248589d3fc4bb19

--
My best regards to you.

     No System Is Safe!
     Dongliang Mu