2024-03-05 16:54:56

by Michal Hocko

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Subject: Re: CVE-2023-52521: bpf: Annotate bpf_long_memcpy with data_race

On Sat 02-03-24 22:53:05, Greg KH wrote:
> Description
> ===========
>
> In the Linux kernel, the following vulnerability has been resolved:
>
> bpf: Annotate bpf_long_memcpy with data_race
>
> syzbot reported a data race splat between two processes trying to
> update the same BPF map value via syscall on different CPUs:
>
> BUG: KCSAN: data-race in bpf_percpu_array_update / bpf_percpu_array_update

I would like to dispute this CVE. It adds data_race annotation which
doesn't have any impact on the code generation.
--
Michal Hocko
SUSE Labs


2024-03-05 22:23:17

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: CVE-2023-52521: bpf: Annotate bpf_long_memcpy with data_race

On Tue, Mar 05, 2024 at 05:54:45PM +0100, Michal Hocko wrote:
> On Sat 02-03-24 22:53:05, Greg KH wrote:
> > Description
> > ===========
> >
> > In the Linux kernel, the following vulnerability has been resolved:
> >
> > bpf: Annotate bpf_long_memcpy with data_race
> >
> > syzbot reported a data race splat between two processes trying to
> > update the same BPF map value via syscall on different CPUs:
> >
> > BUG: KCSAN: data-race in bpf_percpu_array_update / bpf_percpu_array_update
>
> I would like to dispute this CVE. It adds data_race annotation which
> doesn't have any impact on the code generation.

Ah, my fault, I thought the "BUG: KCSAN:" line was a real BUG() call,
it's just a syslog dump, good catch.

I'll go revoke this now, thanks for the review!

greg k-h