linux-kernel - [PATCH] Fix use-after-free oops in Bluetooth HID.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 07 Jul 2007 14:58:39 -0400
From:	David Woodhouse <dwmw2@...radead.org>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Marcel Holtmann <marcel@...tmann.org>,
	Jiri Kosina <jkosina@...e.cz>,
	Dmitry Torokhov <dtor@...ightbb.com>,
	Michal Piotrowski <michal.k.k.piotrowski@...il.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Greg KH <greg@...ah.com>
Subject: [PATCH] Fix use-after-free oops in Bluetooth HID.

When cleaning up HIDP sessions, we currently close the ACL connection
before deregistering the input device. Closing the ACL connection
schedules a workqueue to remove the associated objects from sysfs, but
the input device still refers to them -- and if the workqueue happens to
run before the input device removal, the kernel will oops when trying to
look up PHYSDEVPATH for the removed input device.

Fix this by deregistering the input device before closing the
connections.

Signed-off-by: David Woodhouse <dwmw2@...radead.org>
Signed-off-by: Marcel Holtmann <marcel@...tmann.org>

--- net/bluetooth/hidp/core.c~	2007-07-06 21:34:25.000000000 -0400
+++ net/bluetooth/hidp/core.c	2007-07-06 22:06:48.000000000 -0400
@@ -581,15 +581,6 @@ static int hidp_session(void *arg)
 
 	hidp_del_timer(session);
 
-	fput(session->intr_sock->file);
-
-	wait_event_timeout(*(ctrl_sk->sk_sleep),
-		(ctrl_sk->sk_state == BT_CLOSED), msecs_to_jiffies(500));
-
-	fput(session->ctrl_sock->file);
-
-	__hidp_unlink_session(session);
-
 	if (session->input) {
 		input_unregister_device(session->input);
 		session->input = NULL;
@@ -601,6 +592,15 @@ static int hidp_session(void *arg)
 		hid_free_device(session->hid);
 	}
 
+	fput(session->intr_sock->file);
+
+	wait_event_timeout(*(ctrl_sk->sk_sleep),
+		(ctrl_sk->sk_state == BT_CLOSED), msecs_to_jiffies(500));
+
+	fput(session->ctrl_sock->file);
+
+	__hidp_unlink_session(session);
+
 	up_write(&hidp_session_sem);
 
 	kfree(session);


-- 
dwmw2

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/