From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70FAD3CF1FC; Wed, 15 Jul 2026 08:43:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.132 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784104998; cv=none; b=nzLEbn/5IMA6tRMcirawxn8h+TTqsCOZdEyqsFYl3ZdWx7zoDDR1GeyWeT70kqlXlSTyezw0IaW+hsabJ4IOqOclFS9eB7yB2gKuMoGxtYRlapquoedVDvVptyVAu2yMlY9ZyaKHB3nlP4+Jve8yVH4MPL1/vmlBQ31qRJOUxkE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784104998; c=relaxed/simple; bh=5q0Y5I8yIawo2ynnBMhalYpb2NrtyICRNplR5jao6JE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DJ6jRfX3rpsfHDPmtQ5kqxtbE94EeG3/XBIyPMmBx+A3riVAdUvO7SuPb8aPo5K6giBhZYG3YN3XGUzZvmhJHBwreNOIJpqE3tLhlcmdDzBPi0NUcj6ZBrNWmdQjBknjSDCh+15gRXKYrbULJUVCHOO1ja0D4qI2izshrM7HQFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=gp+8PHzg; arc=none smtp.client-ip=115.124.30.132 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="gp+8PHzg" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1784104978; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=IAnvCrJF1q7w7fmz3FaNGMcNd/i1AfT8lqKrGtMAUZ8=; b=gp+8PHzgqHbvgE9eTyTtdC+3k0o+VdtUuzl470Vcp75RQNNhPnjLd5yf8RMdWKSy/8S9RvTjqfWcX78mRHO1BpDB6m8SiLNUGkFljIWu8hKHaMXmNp2XAWH9nUEbYiKRJ4YoYeeLWKno3LeavteehrVHdXHzr4wpbtd/T9z1wo4= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032089153;MF=lulie@linux.alibaba.com;NM=1;PH=DS;RN=9;SR=0;TI=SMTPD_---0X78Xw0Q_1784104977; Received: from localhost(mailfrom:lulie@linux.alibaba.com fp:SMTPD_---0X78Xw0Q_1784104977 cluster:ay36) by smtp.aliyun-inc.com; Wed, 15 Jul 2026 16:42:57 +0800 From: Philo Lu To: stable@vger.kernel.org Cc: tj@kernel.org, hannes@cmpxchg.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, eadavis@qq.com, surenb@google.com, akpm@linux-foundation.org, dust.li@linux.alibaba.com Subject: [PATCH 6.6.y 1/2] cgroup/psi: Set of->priv to NULL upon file release Date: Wed, 15 Jul 2026 16:42:55 +0800 Message-Id: <20260715084256.43412-2-lulie@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20260715084256.43412-1-lulie@linux.alibaba.com> References: <20260715084256.43412-1-lulie@linux.alibaba.com> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Chen Ridong commit 94a4acfec14615e971eb2c9e1fa6c992c85ff6c6 upstream. Setting of->priv to NULL when the file is released enables earlier bug detection. This allows potential bugs to manifest as NULL pointer dereferences rather than use-after-free errors[1], which are generally more difficult to diagnose. [1] https://lore.kernel.org/cgroups/38ef3ff9-b380-44f0-9315-8b3714b0948d@huaweicloud.com/T/#m8a3b3f88f0ff3da5925d342e90043394f8b2091b Signed-off-by: Chen Ridong Signed-off-by: Tejun Heo Signed-off-by: Philo Lu --- kernel/cgroup/cgroup.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index e787dc0eacd7d..4a7d334be50a5 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4061,6 +4061,7 @@ static void cgroup_file_release(struct kernfs_open_file *of) cft->release(of); put_cgroup_ns(ctx->ns); kfree(ctx); + of->priv = NULL; } static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf, -- 2.47.3