linux-kernel - Re: [PATCH 1/7] fs: introduce kernel_pread

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: <5227a1bb-52e5-d547-2650-b06bee259012@broadcom.com>
Date:   Fri, 23 Aug 2019 12:55:30 -0700
From:   Scott Branden <scott.branden@...adcom.com>
To:     Takashi Iwai <tiwai@...e.de>
Cc:     Luis Chamberlain <mcgrof@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        David Brown <david.brown@...aro.org>,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Shuah Khan <shuah@...nel.org>, bjorn.andersson@...aro.org,
        Shuah Khan <skhan@...uxfoundation.org>,
        Arnd Bergmann <arnd@...db.de>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        linux-fsdevel@...r.kernel.org,
        BCM Kernel Feedback <bcm-kernel-feedback-list@...adcom.com>,
        Olof Johansson <olof@...om.net>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Dan Carpenter <dan.carpenter@...cle.com>,
        Colin Ian King <colin.king@...onical.com>,
        Kees Cook <keescook@...omium.org>,
        linux-kselftest@...r.kernel.org, Mimi Zohar <zohar@...ux.ibm.com>
Subject: Re: [PATCH 1/7] fs: introduce kernel_pread_file* support

Hi Takashi

On 2019-08-23 5:29 a.m., Takashi Iwai wrote:
> On Thu, 22 Aug 2019 21:24:45 +0200,
> Scott Branden wrote:
>> Add kernel_pread_file* support to kernel to allow for partial read
>> of files with an offset into the file.  Existing kernel_read_file
>> functions call new kernel_pread_file functions with offset=0 and
>> flags=KERNEL_PREAD_FLAG_WHOLE.
> Would this change passes the security check like ima?
> I thought security_kernel_post_read_file() checks the whole content
> for calculating the hash...

It passes the fw_run_tests.sh.  How do you test the firmware loader 
passes this security check?


What exactly does this ima do?  How do you enable/disable using it?

Any reasonable device would check the integrity of the firmware image 
being loaded to it.

And, if part of a security model, authenticate the image.

Whatever security check you are referring to is not needed by 
request_firmware_into_buf when loading

a partial file into a buffer.


>
>
> thanks,
>
> Takashi