netdev - Re: [PATCH] net: bridge: Fix jump

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:   Sat, 27 Feb 2021 10:14:43 +0800
From:   Kefeng Wang <wangkefeng.wang@...wei.com>
To:     Cong Wang <xiyou.wangcong@...il.com>
CC:     Roopa Prabhu <roopa@...dia.com>,
        Nikolay Aleksandrov <nikolay@...dia.com>,
        "David S. Miller" <davem@...emloft.net>,
        Linux Kernel Network Developers <netdev@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] net: bridge: Fix jump_label config


On 2021/2/27 4:19, Cong Wang wrote:
> On Thu, Feb 25, 2021 at 5:39 PM Kefeng Wang <wangkefeng.wang@...wei.com> wrote:
>>
>> On 2021/2/26 5:22, Cong Wang wrote:
>>> On Wed, Feb 24, 2021 at 8:03 AM Kefeng Wang <wangkefeng.wang@...wei.com> wrote:
>>>> HAVE_JUMP_LABLE is removed by commit e9666d10a567 ("jump_label: move
>>>> 'asm goto' support test to Kconfig"), use CONFIG_JUMP_LABLE instead
>>>> of HAVE_JUMP_LABLE.
>>>>
>>>> Fixes: 971502d77faa ("bridge: netfilter: unroll NF_HOOK helper in bridge input path")
>>>> Signed-off-by: Kefeng Wang <wangkefeng.wang@...wei.com>
>>> Hmm, why do we have to use a macro here? static_key_false() is defined
>>> in both cases, CONFIG_JUMP_LABEL=y or CONFIG_JUMP_LABEL=n.
>> It seems that all nf_hooks_needed related are using the macro,
>>
>> see net/netfilter/core.c and include/linux/netfilter.h,
>>
>>     #ifdef CONFIG_JUMP_LABEL
>>     struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
>> EXPORT_SYMBOL(nf_hooks_needed);
>> #endif
>>
>>     nf_static_key_inc()/nf_static_key_dec()
> Same question: why? Clearly struct static_key is defined in both cases:

Ok,  I mean that I don't change the original logic, but that's no need 
this macro actually,

it could be built with or without CONFIG_JUMP_LABEL, only increased the 
size a little bit.


>
> #else
> struct static_key {
>          atomic_t enabled;
> };
> #endif  /* CONFIG_JUMP_LABEL */
>
> Thanks.
>