linux-kernel - Re: [PATCH] spi: rspi: avoid uninitialized variable access

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] [day] [month] [year] [list]

Date:   Fri, 11 Nov 2016 09:58:27 +0900
From:   Hiep Cao Minh <cm-hiep@...so.co.jp>
To:     Arnd Bergmann <arnd@...db.de>
CC:     Mark Brown <broonie@...nel.org>,
        Chris Brandt <chris.brandt@...esas.com>,
        linux-spi@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] spi: rspi: avoid uninitialized variable access

Hi Arnd,

On 11/10/2016 07:51 PM, Arnd Bergmann wrote:
> On Thursday, November 10, 2016 6:25:56 PM CET Hiep Cao Minh wrote:
>> Hi Arnd,
>>
>> Thanks for your fixed patch.
>>
>> On 11/08/2016 10:46 PM, Arnd Bergmann wrote:
>>> The newly introduced rspi_pio_transfer_in_or_our() function must
>>> take either a valid 'rx' or 'tx' pointer, and has undefined behavior
>>> if both are NULL, as found by 'gcc -Wmaybe-unintialized':
>>>
>>> drivers/spi/spi-rspi.c: In function 'rspi_pio_transfer_in_or_our':
>>> drivers/spi/spi-rspi.c:558:5: error: 'len' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>> Could you tell me what kind of GCC are you using?
>> I'd like to reproduce it on my environment, too.
>> I am using the Linaro's gcc of
>> "gcc-linaro-arm-linux-gnueabihf-4.8-2014.04_linux".
>> But there is no error message like this on my environment.
> The warning is currently disabled in mainline Linux, but I'm trying to
> address this and hope to still get a revert of 6e8d666e9253 ("Disable
> "maybe-uninitialized" warning globally") into v4.9.
>
> You can build with "make EXTRA_CFLAGS=-Wmaybe-uninitialized" in
> the meantime.
Thanks,
I used your command and found the warning.

Best regards,
Hiep
Jinzai Solution Inc,