linux-kernel - Re: [PATCH/RFC] RDMA/iwpm: Fix uninitialized error code in iwpm_send

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]

Date:   Wed, 29 Nov 2017 09:24:42 +0100
From:   Geert Uytterhoeven <geert@...ux-m68k.org>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Jason Gunthorpe <jgg@...pe.ca>,
        Tatyana Nikolova <Tatyana.E.Nikolova@...el.com>,
        Doug Ledford <dledford@...hat.com>,
        linux-rdma <linux-rdma@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH/RFC] RDMA/iwpm: Fix uninitialized error code in iwpm_send_mapinfo()

Hi Arnd,

On Wed, Nov 29, 2017 at 9:20 AM, Arnd Bergmann <arnd@...db.de> wrote:
> On Wed, Nov 29, 2017 at 9:10 AM, Geert Uytterhoeven
> <geert@...ux-m68k.org> wrote:
>> On Wed, Nov 29, 2017 at 12:08 AM, Jason Gunthorpe <jgg@...pe.ca> wrote:
>>> On Thu, Nov 16, 2017 at 11:26:04AM +0100, Geert Uytterhoeven wrote:
>>>> With gcc-4.1.2:
>>>>
>>>>     drivers/infiniband/core/iwpm_util.c: In function ‘iwpm_send_mapinfo’:
>>>>     drivers/infiniband/core/iwpm_util.c:647: warning: ‘ret’ may be used uninitialized in this function
>>>>
>>>> Indeed, if nl_client is not found in any of the scanned has buckets, ret
>>>> will be used uninitialized.
>>>>
>>>> Preinitialize ret to zero to fix this.
>>>
>>> Did we come to a conclusion if we should apply this to the RMDA tree? The
>>> patch was marked RFC..
>>
>> So far no one commented on what's the correct behavior in case of failure,
>> which was the actual reason for the RFC.
>
> As I said above, I think initializing to -EINVAL would be better than 0 here,

Sorry, I misread your comment as the -EINVAL being part of another function.

> but initializing 'ret' at declaration time is appropriate here (though
> I normally
> try to avoid doing so, see https://rusty.ozlabs.org/?p=232)

+1, but if loops are involved, you have not much choice.
I could move the preinitialization to just before the loop?
Would you like that?

Thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds