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Date:   Tue, 26 Nov 2019 09:12:58 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Marcel Holtmann <marcel@holtmann.org>
Cc:     Alexander Potapenko <glider@google.com>,
        Tomas Bortoli <tomasbortoli@gmail.com>,
        Johan Hedberg <johan.hedberg@gmail.com>,
        Bluez mailing list <linux-bluetooth@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>,
        syzbot+a0d209a4676664613e76@syzkaller.appspotmail.com
Subject: Re: [PATCH] Fix invalid-free in bcsp_close()
Message-ID: <20191126081258.GA1233188@kroah.com>
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On Tue, Nov 26, 2019 at 07:18:46AM +0100, Marcel Holtmann wrote:
> Hi Alexander,
> 
> >>> Syzbot reported an invalid-free that I introduced fixing a memleak.
> >>> 
> >>> bcsp_recv() also frees bcsp->rx_skb but never nullifies its value.
> >>> Nullify bcsp->rx_skb every time it is freed.
> >>> 
> >>> Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
> >>> Reported-by: syzbot+a0d209a4676664613e76@syzkaller.appspotmail.com
> >>> ---
> >>> drivers/bluetooth/hci_bcsp.c | 3 +++
> >>> 1 file changed, 3 insertions(+)
> >> 
> >> patch has been applied to bluetooth-next tree.
> > I believe this bug requires stable tags, as it can potentially provide
> > an arbitrary write (via __skb_unlink) and is triggerable locally with
> > user privileges.
> 
> I do not have a reproducer for it, but if you do, feel free to propose it for -stable inclusion.

Now queued up, thanks.

greg k-h