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Date: Fri, 9 Jun 2017 13:45:47 +0200
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20170609114547.GB4462@noname.redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 1/2] commit: Fix use after free in
 completion
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To: qemu-block@nongnu.org
Cc: mreitz@redhat.com, qemu-devel@nongnu.org, qemu-stable@nongnu.org

Am 02.06.2017 um 23:12 hat Kevin Wolf geschrieben:
> The final bdrv_set_backing_hd() could be working on already freed nodes
> because the commit job drops its references (through BlockBackends) to
> both overlay_bs and top already a bit earlier.
> 
> One way to trigger the bug is hot unplugging a disk for which
> blockdev_mark_auto_del() cancels the block job.
> 
> Fix this by taking BDS-level references while we're still using the
> nodes.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Cc: qemu-stable@nongnu.org