From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: [PATCH-block v2 0/3] blk-cgroup: Fix potential UAF & miscellaneous cleanup Date: Sun, 11 Dec 2022 17:20:55 -0500 Message-ID: <20221211222058.2946830-1-longman@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670797276; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=pSMLLAxVMXnoWPwPea+ElcFQc/uDEfReQyP/onbm6ts=; b=Yx8PRi6/WCqBSS+vFv3eG+d+RJgsaiajZtz1pWe3TZwzgumByBh21XouIQ4dWkd9ahNqMz 3XghyUKqP2wWVWqAapLuiSrLpAct7xqG6E8+a9yi9YlxzJqN14X14oV8AcZaVeZ550mfso a09mg/BKFXmPhugHwbZqVYmwxIWk3aw= List-ID: Content-Type: text/plain; charset="us-ascii" To: Jens Axboe , Tejun Heo , Josef Bacik , Zefan Li , Johannes Weiner , Andrew Morton Cc: cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, =?UTF-8?q?Michal=20Koutn=C3=BD?= , "Dennis Zhou (Facebook)" , Waiman Long v2: - Remove unnecessary rcu_read_{lock|unlock} from cgroup_rstat_css_cpu_flush() in patch 3. It was found that blkcg_destroy_blkgs() may be called with all blkcg references gone. This may potentially cause user-after-free and so should be fixed. The last 2 patches are miscellaneous cleanups of commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()"). Waiman Long (3): bdi, blk-cgroup: Fix potential UAF of blkcg blk-cgroup: Don't flush a blkg if destroyed blk-cgroup: Flush stats at blkgs destruction path block/blk-cgroup.c | 26 ++++++++++++++++++++++++++ include/linux/cgroup.h | 1 + kernel/cgroup/rstat.c | 18 ++++++++++++++++++ mm/backing-dev.c | 8 ++++++-- 4 files changed, 51 insertions(+), 2 deletions(-) -- 2.31.1