This is a note to let you know that I've just added the patch titled
Bluetooth: use correct lock to prevent UAF of hdev object
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bluetooth-use-correct-lock-to-prevent-uaf-of-hdev-object.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e305509e678b3a4af2b3cfd410f409f7cdaabb52 Mon Sep 17 00:00:00 2001
From: Lin Ma <linma@xxxxxxxxxx>
Date: Sun, 30 May 2021 21:37:43 +0800
Subject: Bluetooth: use correct lock to prevent UAF of hdev object
From: Lin Ma <linma@xxxxxxxxxx>
commit e305509e678b3a4af2b3cfd410f409f7cdaabb52 upstream.
The hci_sock_dev_event() function will cleanup the hdev object for
sockets even if this object may still be in used within the
hci_sock_bound_ioctl() function, result in UAF vulnerability.
This patch replace the BH context lock to serialize these affairs
and prevent the race condition.
Signed-off-by: Lin Ma <linma@xxxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bluetooth/hci_sock.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -483,7 +483,7 @@ void hci_sock_dev_event(struct hci_dev *
/* Detach sockets from device */
read_lock(&hci_sk_list.lock);
sk_for_each(sk, &hci_sk_list.head) {
- bh_lock_sock_nested(sk);
+ lock_sock(sk);
if (hci_pi(sk)->hdev == hdev) {
hci_pi(sk)->hdev = NULL;
sk->sk_err = EPIPE;
@@ -492,7 +492,7 @@ void hci_sock_dev_event(struct hci_dev *
hci_dev_put(hdev);
}
- bh_unlock_sock(sk);
+ release_sock(sk);
}
read_unlock(&hci_sk_list.lock);
}
Patches currently in stable-queue which might be from linma@xxxxxxxxxx are
queue-4.4/bluetooth-fix-the-erroneous-flush_work-order.patch
queue-4.4/bluetooth-use-correct-lock-to-prevent-uaf-of-hdev-object.patch
