linux-kernel-mentees.lists.linuxfoundation.org archive mirror
 help / color / mirror / Atom feed
From: Peilin Ye <yepeilin.cs@gmail.com>
To: Marcel Holtmann <marcel@holtmann.org>,
	Johan Hedberg <johan.hedberg@gmail.com>
Cc: netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com,
	Russell King <linux@armlinux.org.uk>,
	"David S . Miller" <davem@davemloft.net>,
	linux-bluetooth@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
	linux-kernel-mentees@lists.linuxfoundation.org,
	Peilin Ye <yepeilin.cs@gmail.com>,
	linux-kernel@vger.kernel.org
Subject: [Linux-kernel-mentees] [PATCH v2] net/bluetooth: Fix slab-out-of-bounds read in hci_extended_inquiry_result_evt()
Date: Thu,  9 Jul 2020 09:02:24 -0400	[thread overview]
Message-ID: <20200709130224.214204-1-yepeilin.cs@gmail.com> (raw)
In-Reply-To: <20200709051802.185168-1-yepeilin.cs@gmail.com>

Check upon `num_rsp` is insufficient. A malformed event packet with a
large `num_rsp` number makes hci_extended_inquiry_result_evt() go out
of bounds. Fix it.

This patch fixes the following syzbot bug:

    https://syzkaller.appspot.com/bug?id=4bf11aa05c4ca51ce0df86e500fce486552dc8d2

Reported-by: syzbot+d8489a79b781849b9c46@syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
---
Changes in v2:
    - Use `skb->len` instead of `skb->truesize` as the length limit.
    - Leave `num_rsp` as of type `int`.

 net/bluetooth/hci_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 03a0759f2fc2..91cb3707d20a 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4375,7 +4375,7 @@ static void hci_extended_inquiry_result_evt(struct hci_dev *hdev,
 
 	BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
 
-	if (!num_rsp)
+	if (!num_rsp || skb->len < num_rsp * sizeof(*info))
 		return;
 
 	if (hci_dev_test_flag(hdev, HCI_PERIODIC_INQ))
-- 
2.25.1

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

  reply	other threads:[~2020-07-09 13:04 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-09  5:18 [Linux-kernel-mentees] [PATCH] net/bluetooth: Fix slab-out-of-bounds read in hci_extended_inquiry_result_evt() Peilin Ye
2020-07-09 13:02 ` Peilin Ye [this message]
2020-07-10 10:43   ` [Linux-kernel-mentees] [PATCH v2] " Greg KH
2020-07-10 16:09   ` [Linux-kernel-mentees] [PATCH v3] " Peilin Ye
2020-07-10 17:08     ` Marcel Holtmann
2021-07-01 15:39   ` maybe similar bug exists for HCI_EV_INQUIRY_RESULT* like [Linux-kernel-mentees] [PATCH v2] net/bluetooth: " Alexander Larkin
2021-07-01 21:06     ` Peilin Ye

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=20200709130224.214204-1-yepeilin.cs@gmail.com \
    --to=yepeilin.cs@gmail.com \
    --cc=davem@davemloft.net \
    --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=linux@armlinux.org.uk \
    --cc=marcel@holtmann.org \
    --cc=netdev@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    /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).