From: Peilin Ye <yepeilin.cs@gmail.com>
To: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Bluez mailing list <linux-bluetooth@vger.kernel.org>,
"open list:NETWORKING [GENERAL]" <netdev@vger.kernel.org>,
linux-kernel-mentees@lists.linuxfoundation.org,
linux-kernel@vger.kernel.org
Subject: Re: [Linux-kernel-mentees] [PATCH net v2] Bluetooth: Fix slab-out-of-bounds read in hci_le_direct_adv_report_evt()
Date: Wed, 11 Nov 2020 00:18:52 -0500 [thread overview]
Message-ID: <20201111051852.GA2491141@PWN> (raw)
In-Reply-To: <AF20F58E-C800-45A8-A5B8-296DE4C0D906@holtmann.org>
On Mon, Nov 09, 2020 at 01:16:53PM +0100, Marcel Holtmann wrote:
> Hi Peilin,
>
> > `num_reports` is not being properly checked. A malformed event packet with
> > a large `num_reports` number makes hci_le_direct_adv_report_evt() read out
> > of bounds. Fix it.
> >
> > Cc: stable@vger.kernel.org
> > Fixes: 2f010b55884e ("Bluetooth: Add support for handling LE Direct Advertising Report events")
> > Reported-and-tested-by: syzbot+24ebd650e20bd263ca01@syzkaller.appspotmail.com
> > Link: https://syzkaller.appspot.com/bug?extid=24ebd650e20bd263ca01
> > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
> > ---
> > Change in v2:
> > - add "Cc: stable@" tag.
> >
> > net/bluetooth/hci_event.c | 12 +++++-------
> > 1 file changed, 5 insertions(+), 7 deletions(-)
> >
> > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> > index 4b7fc430793c..aec43ae488d1 100644
> > --- a/net/bluetooth/hci_event.c
> > +++ b/net/bluetooth/hci_event.c
> > @@ -5863,21 +5863,19 @@ static void hci_le_direct_adv_report_evt(struct hci_dev *hdev,
> > struct sk_buff *skb)
> > {
> > u8 num_reports = skb->data[0];
> > - void *ptr = &skb->data[1];
> > + struct hci_ev_le_direct_adv_info *ev = (void *)&skb->data[1];
> >
> > - hci_dev_lock(hdev);
> > + if (!num_reports || skb->len < num_reports * sizeof(*ev) + 1)
> > + return;
> >
> > - while (num_reports--) {
> > - struct hci_ev_le_direct_adv_info *ev = ptr;
> > + hci_dev_lock(hdev);
> >
> > + for (; num_reports; num_reports--, ev++)
> > process_adv_report(hdev, ev->evt_type, &ev->bdaddr,
> > ev->bdaddr_type, &ev->direct_addr,
> > ev->direct_addr_type, ev->rssi, NULL, 0,
> > false);
> >
> > - ptr += sizeof(*ev);
> > - }
> > -
> > hci_dev_unlock(hdev);
> > }
>
> patch has been applied to bluetooth-next tree.
Thank you for reviewing it,
Peilin Ye
prev parent reply other threads:[~2020-11-11 5:19 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-05 18:09 [Linux-kernel-mentees] [PATCH net] Bluetooth: Fix slab-out-of-bounds read in hci_le_direct_adv_report_evt() Peilin Ye
2020-09-09 7:17 ` [Linux-kernel-mentees] [PATCH net v2] " Peilin Ye
2020-11-09 12:16 ` Marcel Holtmann
2020-11-11 5:18 ` Peilin Ye [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201111051852.GA2491141@PWN \
--to=yepeilin.cs@gmail.com \
--cc=davem@davemloft.net \
--cc=gregkh@linuxfoundation.org \
--cc=johan.hedberg@gmail.com \
--cc=kuba@kernel.org \
--cc=linux-bluetooth@vger.kernel.org \
--cc=linux-kernel-mentees@lists.linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marcel@holtmann.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).