linux-kernel - Re: [PATCH V2] bpf: task_group_seq_get_next: cleanup the usage of get/put_task

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: <05c66b19-d083-57df-b1ee-73035613df36@iogearbox.net>
Date:   Fri, 25 Aug 2023 16:28:17 +0200
From:   Daniel Borkmann <daniel@...earbox.net>
To:     Oleg Nesterov <oleg@...hat.com>, Yonghong Song <yhs@...com>,
        Kui-Feng Lee <kuifeng@...com>,
        Andrii Nakryiko <andrii@...nel.org>
Cc:     "Eric W. Biederman" <ebiederm@...ssion.com>,
        Martin KaFai Lau <martin.lau@...nel.org>,
        bpf@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH V2] bpf: task_group_seq_get_next: cleanup the usage of
 get/put_task_struct

Hi Oleg,

On 8/22/23 2:05 PM, Oleg Nesterov wrote:
> get_pid_task() makes no sense, the code does put_task_struct() soon after.
> Use find_task_by_pid_ns() instead of find_pid_ns + get_pid_task and kill
> put_task_struct(), this allows to do get_task_struct() only once before
> return.
> 
> While at it, kill the unnecessary "if (!pid)" check in the "if (!*tid)"
> block, this matches the next usage of find_pid_ns() + get_pid_task() in
> this function.
> 
> Signed-off-by: Oleg Nesterov <oleg@...hat.com>
> Acked-by: Yonghong Song <yonghong.song@...ux.dev>

Could you rebase this against bpf-next tree so this can run through our BPF
CI? Right now the CI cannot pick the patch up due to merge conflict [0].

Thanks,
Daniel

   [0] https://patchwork.kernel.org/project/netdevbpf/patch/20230822120549.GA22091@redhat.com/