From: Christoph Hellwig <hch@lst.de>
To: Hillf Danton <hdanton@sina.com>
Cc: syzbot <syzbot+1fb38bb7d3ce0fa3e1c4@syzkaller.appspotmail.com>,
axboe@kernel.dk, Christoph Hellwig <hch@lst.de>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] KASAN: use-after-free Read in bdev_evict_inode
Date: Mon, 16 Aug 2021 11:34:52 +0200 [thread overview]
Message-ID: <20210816093452.GB3950@lst.de> (raw)
In-Reply-To: <20210815134930.3216-1-hdanton@sina.com>
On Sun, Aug 15, 2021 at 09:49:30PM +0800, Hillf Danton wrote:
> After putting bdi in wb_exit(), wb->bdi is no longer stable. To fix the uaf,
> add the WB_put bit to avoid derefering a unstable pointer.
>
> Only for thoughts.
This doesn't help with the fact that the bdi needs to be alive
until after inode_detach_wb is called. I posted a patch for that last
week, although I'm about to post a v2 as there are more lingering issues
in this area.
prev parent reply other threads:[~2021-08-16 9:34 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-14 11:07 [syzbot] KASAN: use-after-free Read in bdev_evict_inode syzbot
[not found] ` <20210815134930.3216-1-hdanton@sina.com>
2021-08-16 9:34 ` Christoph Hellwig [this message]
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