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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 20 Oct 2021 10:17:41 +0800 From: Ming Lei <ming.lei@...hat.com> To: Michal Koutný <mkoutny@...e.com> Cc: Quanyang Wang <quanyang.wang@...driver.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 Tue, Oct 19, 2021 at 07:10:26PM +0200, Michal Koutný wrote: > Hi. > > On Tue, Oct 19, 2021 at 06:41:14PM +0800, Quanyang Wang <quanyang.wang@...driver.com> wrote: > > So I add 2 "Fixes tags" here to indicate that 2 commits introduce two > > different issues. > > AFAIU, both the changes are needed to cause the leak, a single patch > alone won't cause the issue. Is that correct? (Perhaps not as I realize, > see below.) > > But on second thought, the problem is the missing percpu_ref_exit() in > the (root) cgroup release path and percpu counter would allocate the > percpu_count_ptr anyway, so 4bfc0bb2c60e is only making the leak more > visible. Is this correct? > > I agree the commit 2b0d3d3e4fcf ("percpu_ref: reduce memory footprint of > percpu_ref in fast path") alone did nothing wrong. 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. Thanks, Ming
Powered by blists - more mailing lists