linux-kernel - Re: [PATCHv10 4/6] drm/meson: Fix overflow implicit truncation warnings

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: <CAK8P3a3_Ea2Szn61D-t--52V-zk+B-sq2mi5YbfMbTim7M9ZAQ@mail.gmail.com>
Date:   Wed, 27 Apr 2022 17:59:16 +0200
From:   Arnd Bergmann <arnd@...db.de>
To:     Sai Prakash Ranjan <quic_saipraka@...cinc.com>
Cc:     Will Deacon <will@...nel.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Arnd Bergmann <arnd@...db.de>,
        Steven Rostedt <rostedt@...dmis.org>,
        Marc Zyngier <maz@...nel.org>,
        Trilok Soni <quic_tsoni@...cinc.com>,
        quic_psodagud@...cinc.com, gregkh <gregkh@...uxfoundation.org>,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-arm-msm <linux-arm-msm@...r.kernel.org>,
        Neil Armstrong <narmstrong@...libre.com>,
        kernel test robot <lkp@...el.com>
Subject: Re: [PATCHv10 4/6] drm/meson: Fix overflow implicit truncation warnings

On Thu, Feb 24, 2022 at 7:07 AM Sai Prakash Ranjan
<quic_saipraka@...cinc.com> wrote:
>
> Fix -Woverflow warnings for drm/meson driver which is a result
> of moving arm64 custom MMIO accessor macros to asm-generic function
> implementations giving a bonus type-checking now and uncovering these
> overflow warnings.
>
> drivers/gpu/drm/meson/meson_viu.c: In function ‘meson_viu_init’:
> drivers/gpu/drm/meson/meson_registers.h:1826:48: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
>  #define  VIU_OSD_BLEND_REORDER(dest, src)      ((src) << (dest * 4))
>                                                 ^
> drivers/gpu/drm/meson/meson_viu.c:472:18: note: in expansion of macro ‘VIU_OSD_BLEND_REORDER’
>    writel_relaxed(VIU_OSD_BLEND_REORDER(0, 1) |
>                   ^~~~~~~~~~~~~~~~~~~~~
>
> Cc: Arnd Bergmann <arnd@...db.de>
> Cc: Neil Armstrong <narmstrong@...libre.com>
> Reported-by: kernel test robot <lkp@...el.com>
> Signed-off-by: Sai Prakash Ranjan <quic_saipraka@...cinc.com>

Reviewed-by: Arnd Bergmann <arnd@...db.de>

It took me a bit to understand why we got the warning in the first place, but I
should have just read the patch description, it's all there....