lkml.org 
[lkml]   [2021]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 4/4] bpf: export bpf_jit_current
From
Date
Le 13/10/2021 à 10:35, Lorenz Bauer a écrit :
> On Tue, 12 Oct 2021 at 17:29, Nicolas Dichtel <nicolas.dichtel@6wind.com> wrote:
>>
>> Le 12/10/2021 à 15:59, Lorenz Bauer a écrit :
>>> Expose bpf_jit_current as a read only value via sysctl.
>>>
>>> Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
>>> ---
>>
>> [snip]
>>
>>> + {
>>> + .procname = "bpf_jit_current",
>>> + .data = &bpf_jit_current,
>>> + .maxlen = sizeof(long),
>>> + .mode = 0400,
>> Why not 0444 ?
>
> This mirrors what the other BPF related sysctls do, which only allow
> access from root with CAP_SYS_ADMIN. I'd prefer 0444 as well, but
> Daniel explicitly locked down these sysctls in
> 2e4a30983b0f9b19b59e38bbf7427d7fdd480d98.
Even after this patch, bpf_jit_enable is 0644.

In fact, if you have CAP_BPF or CAP_SYS_ADMIN, this value has no impact for your
programs. But I you don't have one of these capabilities, it may be rejected,
but you cannot read these values, which help to understand why.


Regards,
Nicolas

\
 
 \ /
  Last update: 2021-10-13 14:30    [W:0.031 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site