linux-kernel - Re: [V2][PATCH] cgroup: fix memory leak caused by missing cgroup_bpf

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: <YXBRyJMru/RbUQK5@blackbook>
Date:   Wed, 20 Oct 2021 19:28:40 +0200
From:   Michal Koutný <mkoutny@...e.com>
To:     Quanyang Wang <quanyang.wang@...driver.com>
Cc:     Ming Lei <ming.lei@...hat.com>, Tejun Heo <tj@...nel.org>,
        Zefan Li <lizefan.x@...edance.com>,
        Johannes Weiner <hannes@...xchg.org>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Andrii Nakryiko <andrii@...nel.org>,
        Jens Axboe <axboe@...nel.dk>, Roman Gushchin <guro@...com>,
        cgroups@...r.kernel.org, linux-kernel@...r.kernel.org,
        netdev@...r.kernel.org, bpf@...r.kernel.org
Subject: Re: [V2][PATCH] cgroup: fix memory leak caused by missing
 cgroup_bpf_offline

On Wed, Oct 20, 2021 at 01:22:06PM +0800, Quanyang Wang <quanyang.wang@...driver.com> wrote:
> > If only precpu_ref data is leaked, it is fine to add "Fixes: 2b0d3d3e4fcf",
> > I thought cgroup_bpf_release() needs to release more for root cgroup, but
> > looks not true.
> For now, I can only observe that precpu_ref data is leaked when running ltp
> testsuite.

I assume you refer to ref->data. I considered the ref->percpu_count_ptr
allocated with __alloc_percpu_gfp(). Could it be that kmemleak won't
detect leaked percpu allocations?

(The patch you sent resolves this as well, I'm just curious.)

Michal