From nobody Sun Jun 14 14:46:43 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B86CC433EF for ; Tue, 17 May 2022 07:31:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240327AbiEQHbZ (ORCPT ); Tue, 17 May 2022 03:31:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232531AbiEQHbX (ORCPT ); Tue, 17 May 2022 03:31:23 -0400 Received: from mail-pf1-x435.google.com (mail-pf1-x435.google.com [IPv6:2607:f8b0:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2023BB16; Tue, 17 May 2022 00:31:22 -0700 (PDT) Received: by mail-pf1-x435.google.com with SMTP id v11so16155427pff.6; Tue, 17 May 2022 00:31:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1f0Z9m+vbuD/qdSf6InzF9TURBzbVV0rFya1IWbNtOo=; b=NpF/ctrLv7ZXdNrGCvD0hg21ovh+HtPwfrjn2Vn5+Kaz9xxkY2bSYYX+jvXLILwQmK GNLyzcfB9p5vtLQyy080RlDn8BI/wOniIJePP1KfvLiFgwFrQd2W2jb1Gjn+tfUWmqSg oBuNRiQ/JvyIjvF86rQ94VnSC37y9e+rwNNOkVJr86rgx1kQ6N+DBrz75BSMppUymB4a 8vIJ3KqS7hfl2k07Q0i8lZWEIxmNWOfhMWwhtEa/aH0p0X8X5hnj6QH0zvS7wnEo439v 7pQqte7CIDeDmOeRajJft70DLqgo/e06I4kSUJW1Ztg9IyrJ/WQKDI2KPfQxXVjnbHgL hPow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1f0Z9m+vbuD/qdSf6InzF9TURBzbVV0rFya1IWbNtOo=; b=zyW3g2G2h2u+w9s5Z7eI4WNhlAQ0MKGV6pfrTtEdtn2Ov4ubtqGBSZWZKrkrSTzoxt xLuu0MG5SnsAf5Pk5xT0D5VBQJJ04bUsNSjHP8kjm5uz7J8+73SHItvs8z6eVWT5bI0l 00oQq/lgZTVNW21/OFG+sSPL2arWq1YuyGylPI4alW4ZxipVrn/FcVZ4PgMekVY+CyVK iu1s3DhvzLBYp/uV9sm0yPjA8407MClb3j8wEvfDdgYDL4qjgQWxd36wj6HxClCzjhac BNc3erEWubkq+0Y2tGFWCRJA8G0i9j69eTDl/4+PVN45WVK3WjSp1xbNRmr2nfaFQUKr qFxg== X-Gm-Message-State: AOAM533xoHriCkdHJs0oa3y4qMUY/QG2sYliwAz1xVeb0fG0MRDrLXCo OOos9jctqbwvykXSkXrKyOI= X-Google-Smtp-Source: ABdhPJwBwlRgEtz4CIsRDE4/P/1KoC5oYgFYvc/cOm0mBXaUY0xTLJMW8V47e9NdfQAaW9fdCky+9g== X-Received: by 2002:a63:89c7:0:b0:3da:ee16:c84 with SMTP id v190-20020a6389c7000000b003daee160c84mr18727427pgd.320.1652772681611; Tue, 17 May 2022 00:31:21 -0700 (PDT) Received: from localhost.localdomain ([103.197.71.140]) by smtp.gmail.com with ESMTPSA id c22-20020a17090ad91600b001df3d5a441bsm914186pjv.53.2022.05.17.00.31.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 May 2022 00:31:21 -0700 (PDT) From: Shida Zhang X-Google-Original-From: Shida Zhang To: tj@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org Cc: zhangshida@kylinos.cn, starzhangzsd@gmail.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: [PATCH] cgroup: fix potential null pointer risk Date: Tue, 17 May 2022 15:31:06 +0800 Message-Id: <20220517073106.1704628-1-zhangshida@kylinos.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" We previously assumed 'parent' could be null, so null pointer judgment should be added. Signed-off-by: Shida Zhang --- kernel/cgroup/cgroup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index adb820e98f24..7f230b0ab644 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5701,7 +5701,8 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) } spin_unlock_irq(&css_set_lock); =20 - cgroup1_check_for_release(parent); + if (parent) + cgroup1_check_for_release(parent); =20 cgroup_bpf_offline(cgrp); =20 --=20 2.25.1