Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1721189

[PATCH 3.18 19/22] Bluetooth: bnep: fix possible might sleep error in bnep_session

Show all headers | View raw

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jeffy Chen <jeffy.chen@rock-chips.com>

commit 25717382c1dd0ddced2059053e3ca5088665f7a5 upstream.

It looks like bnep_session has same pattern as the issue reported in
old rfcomm:

	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (condition)
			break;
		// may call might_sleep here
		schedule();
	}
	__set_current_state(TASK_RUNNING);

Which fixed at:
	dfb2fae Bluetooth: Fix nested sleeps

So let's fix it at the same way, also follow the suggestion of:
https://lwn.net/Articles/628628/

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: AL Yu-Chen Cho <acho@suse.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/bluetooth/bnep/core.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

--- a/net/bluetooth/bnep/core.c
+++ b/net/bluetooth/bnep/core.c
@@ -451,16 +451,16 @@ static int bnep_session(void *arg)
 	struct net_device *dev = s->dev;
 	struct sock *sk = s->sock->sk;
 	struct sk_buff *skb;
-	wait_queue_t wait;
+	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 
 	BT_DBG("");
 
 	set_user_nice(current, -15);
 
-	init_waitqueue_entry(&wait, current);
 	add_wait_queue(sk_sleep(sk), &wait);
 	while (1) {
-		set_current_state(TASK_INTERRUPTIBLE);
+		/* Ensure session->terminate is updated */
+		smp_mb__before_atomic();
 
 		if (atomic_read(&s->terminate))
 			break;
@@ -482,9 +482,8 @@ static int bnep_session(void *arg)
 				break;
 		netif_wake_queue(dev);
 
-		schedule();
+		wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
 	}
-	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(sk_sleep(sk), &wait);
 
 	/* Cleanup session */
@@ -621,7 +620,7 @@ int bnep_del_connection(struct bnep_conn
 	s = __bnep_get_session(req->dst);
 	if (s) {
 		atomic_inc(&s->terminate);
-		wake_up_process(s->task);
+		wake_up_interruptible(sk_sleep(s->sock->sk));
 	} else
 		err = -ENOENT;
 

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 3.18 00/22] 3.18.68-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 19/22] Bluetooth: bnep: fix possible might sleep error in bnep_session Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 05/22] irda: do not leak initialized list.dev to userspace Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 20/22] iio: imu: adis16480: Fix acceleration scale factor for adis16480 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 01/22] dccp: purge write queue in dccp_destroy_sock() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 13/22] cifs: Fix df output for users with quota limits Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 03/22] sctp: fully initialize the IPv6 address in sctp_v6_to_addr() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 07/22] net_sched: fix order of queue length updates in qdisc_replace() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 22/22] ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 17/22] Bluetooth: hidp: fix possible might sleep error in hidp_session_thread Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 09/22] ALSA: core: Fix unexpected error at replacing user TLV Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 06/22] net: sched: fix NULL pointer dereference when action calls some targets Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 04/22] tcp: when rearming RTO, if RTO time is in past then fire RTO ASAP Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 08/22] Input: trackpoint - add new trackpoint firmware ID Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:20 +0200
  [PATCH 3.18 12/22] tracing: Fix freeing of filter in create_filter() when set_str is false Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 18/22] Bluetooth: cmtp: fix possible might sleep error in cmtp_session Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 14/22] cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 02/22] dccp: defer ccid_hc_tx_delete() at dismantle time Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 10/22] ALSA: hda - Add stereo mic quirk for Lenovo G50-70 (17aa:3978) Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 16/22] perf/core: Fix group {cpu,task} validation Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  [PATCH 3.18 21/22] staging: rtl8188eu: add RNX-N150NUB support Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-08-28 10:30 +0200
  Re: [PATCH 3.18 00/22] 3.18.68-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2017-08-28 21:40 +0200
  Re: [PATCH 3.18 00/22] 3.18.68-stable review Guenter Roeck <linux@roeck-us.net> - 2017-08-29 02:10 +0200

csiph-web