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linux-2.6/net/bluetooth/hci_conn.c

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/*
BlueZ - Bluetooth protocol stack for Linux
Copyright (c) 2000-2001, 2010, Code Aurora Forum. All rights reserved.
Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as
published by the Free Software Foundation;
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
SOFTWARE IS DISCLAIMED.
*/
/* Bluetooth HCI connection handling. */
#include <linux/export.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/a2mp.h>
#include <net/bluetooth/smp.h>
static void hci_le_create_connection(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
struct hci_cp_le_create_conn cp;
conn->state = BT_CONNECT;
conn->out = true;
conn->link_mode |= HCI_LM_MASTER;
conn->sec_level = BT_SECURITY_LOW;
memset(&cp, 0, sizeof(cp));
cp.scan_interval = __constant_cpu_to_le16(0x0060);
cp.scan_window = __constant_cpu_to_le16(0x0030);
bacpy(&cp.peer_addr, &conn->dst);
cp.peer_addr_type = conn->dst_type;
cp.conn_interval_min = __constant_cpu_to_le16(0x0028);
cp.conn_interval_max = __constant_cpu_to_le16(0x0038);
cp.supervision_timeout = __constant_cpu_to_le16(0x002a);
cp.min_ce_len = __constant_cpu_to_le16(0x0000);
cp.max_ce_len = __constant_cpu_to_le16(0x0000);
hci_send_cmd(hdev, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
}
static void hci_le_create_connection_cancel(struct hci_conn *conn)
{
hci_send_cmd(conn->hdev, HCI_OP_LE_CREATE_CONN_CANCEL, 0, NULL);
}
static void hci_acl_create_connection(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
struct inquiry_entry *ie;
struct hci_cp_create_conn cp;
BT_DBG("hcon %p", conn);
conn->state = BT_CONNECT;
conn->out = true;
conn->link_mode = HCI_LM_MASTER;
conn->attempt++;
conn->link_policy = hdev->link_policy;
memset(&cp, 0, sizeof(cp));
bacpy(&cp.bdaddr, &conn->dst);
cp.pscan_rep_mode = 0x02;
ie = hci_inquiry_cache_lookup(hdev, &conn->dst);
if (ie) {
if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
cp.pscan_rep_mode = ie->data.pscan_rep_mode;
cp.pscan_mode = ie->data.pscan_mode;
cp.clock_offset = ie->data.clock_offset |
__constant_cpu_to_le16(0x8000);
}
memcpy(conn->dev_class, ie->data.dev_class, 3);
if (ie->data.ssp_mode > 0)
set_bit(HCI_CONN_SSP_ENABLED, &conn->flags);
}
cp.pkt_type = cpu_to_le16(conn->pkt_type);
if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
cp.role_switch = 0x01;
else
cp.role_switch = 0x00;
hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
}
static void hci_acl_create_connection_cancel(struct hci_conn *conn)
{
struct hci_cp_create_conn_cancel cp;
BT_DBG("hcon %p", conn);
if (conn->hdev->hci_ver < BLUETOOTH_VER_1_2)
return;
bacpy(&cp.bdaddr, &conn->dst);
hci_send_cmd(conn->hdev, HCI_OP_CREATE_CONN_CANCEL, sizeof(cp), &cp);
}
void hci_acl_disconn(struct hci_conn *conn, __u8 reason)
{
struct hci_cp_disconnect cp;
BT_DBG("hcon %p", conn);
conn->state = BT_DISCONN;
cp.handle = cpu_to_le16(conn->handle);
cp.reason = reason;
hci_send_cmd(conn->hdev, HCI_OP_DISCONNECT, sizeof(cp), &cp);
}
static void hci_amp_disconn(struct hci_conn *conn, __u8 reason)
{
struct hci_cp_disconn_phy_link cp;
BT_DBG("hcon %p", conn);
conn->state = BT_DISCONN;
cp.phy_handle = HCI_PHY_HANDLE(conn->handle);
cp.reason = reason;
hci_send_cmd(conn->hdev, HCI_OP_DISCONN_PHY_LINK,
sizeof(cp), &cp);
}
static void hci_add_sco(struct hci_conn *conn, __u16 handle)
{
struct hci_dev *hdev = conn->hdev;
struct hci_cp_add_sco cp;
BT_DBG("hcon %p", conn);
conn->state = BT_CONNECT;
conn->out = true;
conn->attempt++;
cp.handle = cpu_to_le16(handle);
cp.pkt_type = cpu_to_le16(conn->pkt_type);
hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
}
void hci_setup_sync(struct hci_conn *conn, __u16 handle)
{
struct hci_dev *hdev = conn->hdev;
struct hci_cp_setup_sync_conn cp;
BT_DBG("hcon %p", conn);
conn->state = BT_CONNECT;
conn->out = true;
conn->attempt++;
cp.handle = cpu_to_le16(handle);
cp.pkt_type = cpu_to_le16(conn->pkt_type);
cp.tx_bandwidth = __constant_cpu_to_le32(0x00001f40);
cp.rx_bandwidth = __constant_cpu_to_le32(0x00001f40);
cp.max_latency = __constant_cpu_to_le16(0xffff);
cp.voice_setting = cpu_to_le16(hdev->voice_setting);
cp.retrans_effort = 0xff;
hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp);
}
void hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max,
u16 latency, u16 to_multiplier)
{
struct hci_cp_le_conn_update cp;
struct hci_dev *hdev = conn->hdev;
memset(&cp, 0, sizeof(cp));
cp.handle = cpu_to_le16(conn->handle);
cp.conn_interval_min = cpu_to_le16(min);
cp.conn_interval_max = cpu_to_le16(max);
cp.conn_latency = cpu_to_le16(latency);
cp.supervision_timeout = cpu_to_le16(to_multiplier);
cp.min_ce_len = __constant_cpu_to_le16(0x0001);
cp.max_ce_len = __constant_cpu_to_le16(0x0001);
hci_send_cmd(hdev, HCI_OP_LE_CONN_UPDATE, sizeof(cp), &cp);
}
void hci_le_start_enc(struct hci_conn *conn, __le16 ediv, __u8 rand[8],
__u8 ltk[16])
{
struct hci_dev *hdev = conn->hdev;
struct hci_cp_le_start_enc cp;
BT_DBG("hcon %p", conn);
memset(&cp, 0, sizeof(cp));
cp.handle = cpu_to_le16(conn->handle);
memcpy(cp.ltk, ltk, sizeof(cp.ltk));
cp.ediv = ediv;
memcpy(cp.rand, rand, sizeof(cp.rand));
hci_send_cmd(hdev, HCI_OP_LE_START_ENC, sizeof(cp), &cp);
}
/* Device _must_ be locked */
void hci_sco_setup(struct hci_conn *conn, __u8 status)
{
struct hci_conn *sco = conn->link;
if (!sco)
return;
BT_DBG("hcon %p", conn);
if (!status) {
if (lmp_esco_capable(conn->hdev))
hci_setup_sync(sco, conn->handle);
else
hci_add_sco(sco, conn->handle);
} else {
hci_proto_connect_cfm(sco, status);
hci_conn_del(sco);
}
}
static void hci_conn_disconnect(struct hci_conn *conn)
{
__u8 reason = hci_proto_disconn_ind(conn);
switch (conn->type) {
case AMP_LINK:
hci_amp_disconn(conn, reason);
break;
default:
hci_acl_disconn(conn, reason);
break;
}
}
static void hci_conn_timeout(struct work_struct *work)
{
struct hci_conn *conn = container_of(work, struct hci_conn,
disc_work.work);
BT_DBG("hcon %p state %s", conn, state_to_string(conn->state));
if (atomic_read(&conn->refcnt))
return;
switch (conn->state) {
case BT_CONNECT:
case BT_CONNECT2:
if (conn->out) {
if (conn->type == ACL_LINK)
hci_acl_create_connection_cancel(conn);
else if (conn->type == LE_LINK)
hci_le_create_connection_cancel(conn);
}
break;
case BT_CONFIG:
case BT_CONNECTED:
hci_conn_disconnect(conn);
break;
default:
conn->state = BT_CLOSED;
break;
}
}
/* Enter sniff mode */
static void hci_conn_enter_sniff_mode(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
BT_DBG("hcon %p mode %d", conn, conn->mode);
if (test_bit(HCI_RAW, &hdev->flags))
return;
if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
return;
if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
return;
if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
struct hci_cp_sniff_subrate cp;
cp.handle = cpu_to_le16(conn->handle);
cp.max_latency = __constant_cpu_to_le16(0);
cp.min_remote_timeout = __constant_cpu_to_le16(0);
cp.min_local_timeout = __constant_cpu_to_le16(0);
hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
}
if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
struct hci_cp_sniff_mode cp;
cp.handle = cpu_to_le16(conn->handle);
cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
cp.attempt = __constant_cpu_to_le16(4);
cp.timeout = __constant_cpu_to_le16(1);
hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
}
}
static void hci_conn_idle(unsigned long arg)
{
struct hci_conn *conn = (void *) arg;
BT_DBG("hcon %p mode %d", conn, conn->mode);
hci_conn_enter_sniff_mode(conn);
}
static void hci_conn_auto_accept(unsigned long arg)
{
struct hci_conn *conn = (void *) arg;
struct hci_dev *hdev = conn->hdev;
hci_send_cmd(hdev, HCI_OP_USER_CONFIRM_REPLY, sizeof(conn->dst),
&conn->dst);
}
struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst)
{
struct hci_conn *conn;
BT_DBG("%s dst %pMR", hdev->name, dst);
conn = kzalloc(sizeof(struct hci_conn), GFP_KERNEL);
if (!conn)
return NULL;
bacpy(&conn->dst, dst);
conn->hdev = hdev;
conn->type = type;
conn->mode = HCI_CM_ACTIVE;
conn->state = BT_OPEN;
conn->auth_type = HCI_AT_GENERAL_BONDING;
conn->io_capability = hdev->io_capability;
conn->remote_auth = 0xff;
conn->key_type = 0xff;
set_bit(HCI_CONN_POWER_SAVE, &conn->flags);
Bluetooth: Add different pairing timeout for Legacy Pairing The Bluetooth stack uses a reference counting for all established ACL links and if no user (L2CAP connection) is present, the link will be terminated to save power. The problem part is the dedicated pairing when using Legacy Pairing (Bluetooth 2.0 and before). At that point no user is present and pairing attempts will be disconnected within 10 seconds or less. In previous kernel version this was not a problem since the disconnect timeout wasn't triggered on incoming connections for the first time. However this caused issues with broken host stacks that kept the connections around after dedicated pairing. When the support for Simple Pairing got added, the link establishment procedure needed to be changed and now causes issues when using Legacy Pairing When using Simple Pairing it is possible to do a proper reference counting of ACL link users. With Legacy Pairing this is not possible since the specification is unclear in some areas and too many broken Bluetooth devices have already been deployed. So instead of trying to deal with all the broken devices, a special pairing timeout will be introduced that increases the timeout to 60 seconds when pairing is triggered. If a broken devices now puts the stack into an unforeseen state, the worst that happens is the disconnect timeout triggers after 120 seconds instead of 4 seconds. This allows successful pairings with legacy and broken devices now. Based on a report by Johan Hedberg <johan.hedberg@nokia.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-04-26 18:01:22 +00:00
conn->disc_timeout = HCI_DISCONN_TIMEOUT;
switch (type) {
case ACL_LINK:
conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
break;
case SCO_LINK:
if (lmp_esco_capable(hdev))
conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
(hdev->esco_type & EDR_ESCO_MASK);
else
conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
break;
case ESCO_LINK:
conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
break;
}
skb_queue_head_init(&conn->data_q);
INIT_LIST_HEAD(&conn->chan_list);
INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
setup_timer(&conn->idle_timer, hci_conn_idle, (unsigned long)conn);
setup_timer(&conn->auto_accept_timer, hci_conn_auto_accept,
(unsigned long) conn);
atomic_set(&conn->refcnt, 0);
hci_dev_hold(hdev);
hci_conn_hash_add(hdev, conn);
if (hdev->notify)
hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
atomic_set(&conn->devref, 0);
Bluetooth: Fix issue with sysfs handling for connections Due to a semantic changes in flush_workqueue() the current approach of synchronizing the sysfs handling for connections doesn't work anymore. The whole approach is actually fully broken and based on assumptions that are no longer valid. With the introduction of Simple Pairing support, the creation of low-level ACL links got changed. This change invalidates the reason why in the past two independent work queues have been used for adding/removing sysfs devices. The adding of the actual sysfs device is now postponed until the host controller successfully assigns an unique handle to that link. So the real synchronization happens inside the controller and not the host. The only left-over problem is that some internals of the sysfs device handling are not initialized ahead of time. This leaves potential access to invalid data and can cause various NULL pointer dereferences. To fix this a new function makes sure that all sysfs details are initialized when an connection attempt is made. The actual sysfs device is only registered when the connection has been successfully established. To avoid a race condition with the registration, the check if a device is registered has been moved into the removal work. As an extra protection two flush_work() calls are left in place to make sure a previous add/del work has been completed first. Based on a report by Marc Pignat <marc.pignat@hevs.ch> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Tested-by: Justin P. Mattock <justinmattock@gmail.com> Tested-by: Roger Quadros <ext-roger.quadros@nokia.com> Tested-by: Marc Pignat <marc.pignat@hevs.ch>
2009-05-03 01:24:06 +00:00
hci_conn_init_sysfs(conn);
return conn;
}
int hci_conn_del(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);
del_timer(&conn->idle_timer);
cancel_delayed_work_sync(&conn->disc_work);
del_timer(&conn->auto_accept_timer);
if (conn->type == ACL_LINK) {
struct hci_conn *sco = conn->link;
if (sco)
sco->link = NULL;
/* Unacked frames */
hdev->acl_cnt += conn->sent;
} else if (conn->type == LE_LINK) {
if (hdev->le_pkts)
hdev->le_cnt += conn->sent;
else
hdev->acl_cnt += conn->sent;
} else {
struct hci_conn *acl = conn->link;
if (acl) {
acl->link = NULL;
hci_conn_put(acl);
}
}
hci_chan_list_flush(conn);
if (conn->amp_mgr)
amp_mgr_put(conn->amp_mgr);
hci_conn_hash_del(hdev, conn);
if (hdev->notify)
hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
skb_queue_purge(&conn->data_q);
hci_conn_put_device(conn);
Bluetooth: Move hci_conn_del_sysfs() back to avoid device destruct too early The following commit introduce a regression: commit 7d0db0a373195385a2e0b19d1f5e4b186fdcffac Author: Marcel Holtmann <marcel@holtmann.org> Date: Mon Jul 14 20:13:51 2008 +0200 [Bluetooth] Use a more unique bus name for connections I get panic as following (by netconsole): [ 2709.344034] usb 5-1: new full speed USB device using uhci_hcd and address 4 [ 2709.505776] usb 5-1: configuration #1 chosen from 1 choice [ 2709.569207] Bluetooth: Generic Bluetooth USB driver ver 0.4 [ 2709.570169] usbcore: registered new interface driver btusb [ 2845.742781] BUG: unable to handle kernel paging request at 6b6b6c2f [ 2845.742958] IP: [<c015515c>] __lock_acquire+0x6c/0xa80 [ 2845.743087] *pde = 00000000 [ 2845.743206] Oops: 0002 [#1] SMP [ 2845.743377] last sysfs file: /sys/class/bluetooth/hci0/hci0:6/type [ 2845.743742] Modules linked in: btusb netconsole snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss rfcomm l2cap bluetooth vfat fuse snd_hda_codec_idt snd_hda_intel snd_hda_codec snd_hwdep snd_pcm pl2303 snd_timer psmouse usbserial snd 3c59x e100 serio_raw soundcore i2c_i801 intel_agp mii agpgart snd_page_alloc rtc_cmos rtc_core thermal processor rtc_lib button thermal_sys sg evdev [ 2845.743742] [ 2845.743742] Pid: 0, comm: swapper Not tainted (2.6.29-rc5-smp #54) Dell DM051 [ 2845.743742] EIP: 0060:[<c015515c>] EFLAGS: 00010002 CPU: 0 [ 2845.743742] EIP is at __lock_acquire+0x6c/0xa80 [ 2845.743742] EAX: 00000046 EBX: 00000046 ECX: 6b6b6b6b EDX: 00000002 [ 2845.743742] ESI: 6b6b6b6b EDI: 00000000 EBP: c064fd14 ESP: c064fcc8 [ 2845.743742] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 [ 2845.743742] Process swapper (pid: 0, ti=c064e000 task=c05d1400 task.ti=c064e000) [ 2845.743742] Stack: [ 2845.743742] c05d1400 00000002 c05d1400 00000001 00000002 00000000 f65388dc c05d1400 [ 2845.743742] 6b6b6b6b 00000292 c064fd0c c0153732 00000000 00000000 00000001 f700fa50 [ 2845.743742] 00000046 00000000 00000000 c064fd40 c0155be6 00000000 00000002 00000001 [ 2845.743742] Call Trace: [ 2845.743742] [<c0153732>] ? trace_hardirqs_on_caller+0x72/0x1c0 [ 2845.743742] [<c0155be6>] ? lock_acquire+0x76/0xa0 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c046c885>] ? _spin_lock_irqsave+0x45/0x80 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1f94>] ? skb_queue_purge+0x14/0x20 [ 2845.743742] [<f8171f5a>] ? hci_conn_del+0x10a/0x1c0 [bluetooth] [ 2845.743742] [<f81399c9>] ? l2cap_disconn_ind+0x59/0xb0 [l2cap] [ 2845.743742] [<f81795ce>] ? hci_conn_del_sysfs+0x8e/0xd0 [bluetooth] [ 2845.743742] [<f8175758>] ? hci_event_packet+0x5f8/0x31c0 [bluetooth] [ 2845.743742] [<c03dfe19>] ? sock_def_readable+0x59/0x80 [ 2845.743742] [<c046c14d>] ? _read_unlock+0x1d/0x20 [ 2845.743742] [<f8178aa9>] ? hci_send_to_sock+0xe9/0x1d0 [bluetooth] [ 2845.743742] [<c015388b>] ? trace_hardirqs_on+0xb/0x10 [ 2845.743742] [<f816fa6a>] ? hci_rx_task+0x2ba/0x490 [bluetooth] [ 2845.743742] [<c0133661>] ? tasklet_action+0x31/0xc0 [ 2845.743742] [<c013367c>] ? tasklet_action+0x4c/0xc0 [ 2845.743742] [<c0132eb7>] ? __do_softirq+0xa7/0x170 [ 2845.743742] [<c0116dec>] ? ack_apic_level+0x5c/0x1c0 [ 2845.743742] [<c0132fd7>] ? do_softirq+0x57/0x60 [ 2845.743742] [<c01333dc>] ? irq_exit+0x7c/0x90 [ 2845.743742] [<c01055bb>] ? do_IRQ+0x4b/0x90 [ 2845.743742] [<c01333d5>] ? irq_exit+0x75/0x90 [ 2845.743742] [<c010392c>] ? common_interrupt+0x2c/0x34 [ 2845.743742] [<c010a14f>] ? mwait_idle+0x4f/0x70 [ 2845.743742] [<c0101c05>] ? cpu_idle+0x65/0xb0 [ 2845.743742] [<c045731e>] ? rest_init+0x4e/0x60 [ 2845.743742] Code: 0f 84 69 02 00 00 83 ff 07 0f 87 1e 06 00 00 85 ff 0f 85 08 05 00 00 8b 4d cc 8b 49 04 85 c9 89 4d d4 0f 84 f7 04 00 00 8b 75 d4 <f0> ff 86 c4 00 00 00 89 f0 e8 56 a9 ff ff 85 c0 0f 85 6e 03 00 [ 2845.743742] EIP: [<c015515c>] __lock_acquire+0x6c/0xa80 SS:ESP 0068:c064fcc8 [ 2845.743742] ---[ end trace 4c985b38f022279f ]--- [ 2845.743742] Kernel panic - not syncing: Fatal exception in interrupt [ 2845.743742] ------------[ cut here ]------------ [ 2845.743742] WARNING: at kernel/smp.c:329 smp_call_function_many+0x151/0x200() [ 2845.743742] Hardware name: Dell DM051 [ 2845.743742] Modules linked in: btusb netconsole snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss rfcomm l2cap bluetooth vfat fuse snd_hda_codec_idt snd_hda_intel snd_hda_codec snd_hwdep snd_pcm pl2303 snd_timer psmouse usbserial snd 3c59x e100 serio_raw soundcore i2c_i801 intel_agp mii agpgart snd_page_alloc rtc_cmos rtc_core thermal processor rtc_lib button thermal_sys sg evdev [ 2845.743742] Pid: 0, comm: swapper Tainted: G D 2.6.29-rc5-smp #54 [ 2845.743742] Call Trace: [ 2845.743742] [<c012e076>] warn_slowpath+0x86/0xa0 [ 2845.743742] [<c015041b>] ? trace_hardirqs_off+0xb/0x10 [ 2845.743742] [<c0146384>] ? up+0x14/0x40 [ 2845.743742] [<c012e661>] ? release_console_sem+0x31/0x1e0 [ 2845.743742] [<c046c8ab>] ? _spin_lock_irqsave+0x6b/0x80 [ 2845.743742] [<c015041b>] ? trace_hardirqs_off+0xb/0x10 [ 2845.743742] [<c046c900>] ? _read_lock_irqsave+0x40/0x80 [ 2845.743742] [<c012e7f2>] ? release_console_sem+0x1c2/0x1e0 [ 2845.743742] [<c0146384>] ? up+0x14/0x40 [ 2845.743742] [<c015041b>] ? trace_hardirqs_off+0xb/0x10 [ 2845.743742] [<c046a3d7>] ? __mutex_unlock_slowpath+0x97/0x160 [ 2845.743742] [<c046a563>] ? mutex_trylock+0xb3/0x180 [ 2845.743742] [<c046a4a8>] ? mutex_unlock+0x8/0x10 [ 2845.743742] [<c015b991>] smp_call_function_many+0x151/0x200 [ 2845.743742] [<c010a1a0>] ? stop_this_cpu+0x0/0x40 [ 2845.743742] [<c015ba61>] smp_call_function+0x21/0x30 [ 2845.743742] [<c01137ae>] native_smp_send_stop+0x1e/0x50 [ 2845.743742] [<c012e0f5>] panic+0x55/0x110 [ 2845.743742] [<c01065a8>] oops_end+0xb8/0xc0 [ 2845.743742] [<c010668f>] die+0x4f/0x70 [ 2845.743742] [<c011a8c9>] do_page_fault+0x269/0x610 [ 2845.743742] [<c011a660>] ? do_page_fault+0x0/0x610 [ 2845.743742] [<c046cbaf>] error_code+0x77/0x7c [ 2845.743742] [<c015515c>] ? __lock_acquire+0x6c/0xa80 [ 2845.743742] [<c0153732>] ? trace_hardirqs_on_caller+0x72/0x1c0 [ 2845.743742] [<c0155be6>] lock_acquire+0x76/0xa0 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c046c885>] _spin_lock_irqsave+0x45/0x80 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1aad>] skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1f94>] skb_queue_purge+0x14/0x20 [ 2845.743742] [<f8171f5a>] hci_conn_del+0x10a/0x1c0 [bluetooth] [ 2845.743742] [<f81399c9>] ? l2cap_disconn_ind+0x59/0xb0 [l2cap] [ 2845.743742] [<f81795ce>] ? hci_conn_del_sysfs+0x8e/0xd0 [bluetooth] [ 2845.743742] [<f8175758>] hci_event_packet+0x5f8/0x31c0 [bluetooth] [ 2845.743742] [<c03dfe19>] ? sock_def_readable+0x59/0x80 [ 2845.743742] [<c046c14d>] ? _read_unlock+0x1d/0x20 [ 2845.743742] [<f8178aa9>] ? hci_send_to_sock+0xe9/0x1d0 [bluetooth] [ 2845.743742] [<c015388b>] ? trace_hardirqs_on+0xb/0x10 [ 2845.743742] [<f816fa6a>] hci_rx_task+0x2ba/0x490 [bluetooth] [ 2845.743742] [<c0133661>] ? tasklet_action+0x31/0xc0 [ 2845.743742] [<c013367c>] tasklet_action+0x4c/0xc0 [ 2845.743742] [<c0132eb7>] __do_softirq+0xa7/0x170 [ 2845.743742] [<c0116dec>] ? ack_apic_level+0x5c/0x1c0 [ 2845.743742] [<c0132fd7>] do_softirq+0x57/0x60 [ 2845.743742] [<c01333dc>] irq_exit+0x7c/0x90 [ 2845.743742] [<c01055bb>] do_IRQ+0x4b/0x90 [ 2845.743742] [<c01333d5>] ? irq_exit+0x75/0x90 [ 2845.743742] [<c010392c>] common_interrupt+0x2c/0x34 [ 2845.743742] [<c010a14f>] ? mwait_idle+0x4f/0x70 [ 2845.743742] [<c0101c05>] cpu_idle+0x65/0xb0 [ 2845.743742] [<c045731e>] rest_init+0x4e/0x60 [ 2845.743742] ---[ end trace 4c985b38f02227a0 ]--- [ 2845.743742] ------------[ cut here ]------------ [ 2845.743742] WARNING: at kernel/smp.c:226 smp_call_function_single+0x8e/0x110() [ 2845.743742] Hardware name: Dell DM051 [ 2845.743742] Modules linked in: btusb netconsole snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss rfcomm l2cap bluetooth vfat fuse snd_hda_codec_idt snd_hda_intel snd_hda_codec snd_hwdep snd_pcm pl2303 snd_timer psmouse usbserial snd 3c59x e100 serio_raw soundcore i2c_i801 intel_agp mii agpgart snd_page_alloc rtc_cmos rtc_core thermal processor rtc_lib button thermal_sys sg evdev [ 2845.743742] Pid: 0, comm: swapper Tainted: G D W 2.6.29-rc5-smp #54 [ 2845.743742] Call Trace: [ 2845.743742] [<c012e076>] warn_slowpath+0x86/0xa0 [ 2845.743742] [<c012e000>] ? warn_slowpath+0x10/0xa0 [ 2845.743742] [<c015041b>] ? trace_hardirqs_off+0xb/0x10 [ 2845.743742] [<c0146384>] ? up+0x14/0x40 [ 2845.743742] [<c012e661>] ? release_console_sem+0x31/0x1e0 [ 2845.743742] [<c046c8ab>] ? _spin_lock_irqsave+0x6b/0x80 [ 2845.743742] [<c015041b>] ? trace_hardirqs_off+0xb/0x10 [ 2845.743742] [<c046c900>] ? _read_lock_irqsave+0x40/0x80 [ 2845.743742] [<c012e7f2>] ? release_console_sem+0x1c2/0x1e0 [ 2845.743742] [<c0146384>] ? up+0x14/0x40 [ 2845.743742] [<c015b7be>] smp_call_function_single+0x8e/0x110 [ 2845.743742] [<c010a1a0>] ? stop_this_cpu+0x0/0x40 [ 2845.743742] [<c026d23f>] ? cpumask_next_and+0x1f/0x40 [ 2845.743742] [<c015b95a>] smp_call_function_many+0x11a/0x200 [ 2845.743742] [<c010a1a0>] ? stop_this_cpu+0x0/0x40 [ 2845.743742] [<c015ba61>] smp_call_function+0x21/0x30 [ 2845.743742] [<c01137ae>] native_smp_send_stop+0x1e/0x50 [ 2845.743742] [<c012e0f5>] panic+0x55/0x110 [ 2845.743742] [<c01065a8>] oops_end+0xb8/0xc0 [ 2845.743742] [<c010668f>] die+0x4f/0x70 [ 2845.743742] [<c011a8c9>] do_page_fault+0x269/0x610 [ 2845.743742] [<c011a660>] ? do_page_fault+0x0/0x610 [ 2845.743742] [<c046cbaf>] error_code+0x77/0x7c [ 2845.743742] [<c015515c>] ? __lock_acquire+0x6c/0xa80 [ 2845.743742] [<c0153732>] ? trace_hardirqs_on_caller+0x72/0x1c0 [ 2845.743742] [<c0155be6>] lock_acquire+0x76/0xa0 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c046c885>] _spin_lock_irqsave+0x45/0x80 [ 2845.743742] [<c03e1aad>] ? skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1aad>] skb_dequeue+0x1d/0x70 [ 2845.743742] [<c03e1f94>] skb_queue_purge+0x14/0x20 [ 2845.743742] [<f8171f5a>] hci_conn_del+0x10a/0x1c0 [bluetooth] [ 2845.743742] [<f81399c9>] ? l2cap_disconn_ind+0x59/0xb0 [l2cap] [ 2845.743742] [<f81795ce>] ? hci_conn_del_sysfs+0x8e/0xd0 [bluetooth] [ 2845.743742] [<f8175758>] hci_event_packet+0x5f8/0x31c0 [bluetooth] [ 2845.743742] [<c03dfe19>] ? sock_def_readable+0x59/0x80 [ 2845.743742] [<c046c14d>] ? _read_unlock+0x1d/0x20 [ 2845.743742] [<f8178aa9>] ? hci_send_to_sock+0xe9/0x1d0 [bluetooth] [ 2845.743742] [<c015388b>] ? trace_hardirqs_on+0xb/0x10 [ 2845.743742] [<f816fa6a>] hci_rx_task+0x2ba/0x490 [bluetooth] [ 2845.743742] [<c0133661>] ? tasklet_action+0x31/0xc0 [ 2845.743742] [<c013367c>] tasklet_action+0x4c/0xc0 [ 2845.743742] [<c0132eb7>] __do_softirq+0xa7/0x170 [ 2845.743742] [<c0116dec>] ? ack_apic_level+0x5c/0x1c0 [ 2845.743742] [<c0132fd7>] do_softirq+0x57/0x60 [ 2845.743742] [<c01333dc>] irq_exit+0x7c/0x90 [ 2845.743742] [<c01055bb>] do_IRQ+0x4b/0x90 [ 2845.743742] [<c01333d5>] ? irq_exit+0x75/0x90 [ 2845.743742] [<c010392c>] common_interrupt+0x2c/0x34 [ 2845.743742] [<c010a14f>] ? mwait_idle+0x4f/0x70 [ 2845.743742] [<c0101c05>] cpu_idle+0x65/0xb0 [ 2845.743742] [<c045731e>] rest_init+0x4e/0x60 [ 2845.743742] ---[ end trace 4c985b38f02227a1 ]--- [ 2845.743742] Rebooting in 3 seconds.. My logitec bluetooth mouse trying connect to pc, but pc side reject the connection again and again. then panic happens. The reason is due to hci_conn_del_sysfs now called in hci_event_packet, the del work is done in a workqueue, so it's possible done before skb_queue_purge called. I move the hci_conn_del_sysfs after skb_queue_purge just as that before marcel's commit. Remove the hci_conn_del_sysfs in hci_conn_hash_flush as well due to hci_conn_del will deal with the work. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-02-21 08:13:34 +00:00
hci_dev_put(hdev);
if (conn->handle == 0)
kfree(conn);
return 0;
}
struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src)
{
int use_src = bacmp(src, BDADDR_ANY);
struct hci_dev *hdev = NULL, *d;
BT_DBG("%pMR -> %pMR", src, dst);
read_lock(&hci_dev_list_lock);
list_for_each_entry(d, &hci_dev_list, list) {
if (!test_bit(HCI_UP, &d->flags) ||
test_bit(HCI_RAW, &d->flags) ||
d->dev_type != HCI_BREDR)
continue;
/* Simple routing:
* No source address - find interface with bdaddr != dst
* Source address - find interface with bdaddr == src
*/
if (use_src) {
if (!bacmp(&d->bdaddr, src)) {
hdev = d; break;
}
} else {
if (bacmp(&d->bdaddr, dst)) {
hdev = d; break;
}
}
}
if (hdev)
hdev = hci_dev_hold(hdev);
read_unlock(&hci_dev_list_lock);
return hdev;
}
EXPORT_SYMBOL(hci_get_route);
static struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
u8 dst_type, u8 sec_level, u8 auth_type)
{
struct hci_conn *le;
if (test_bit(HCI_LE_PERIPHERAL, &hdev->flags))
return ERR_PTR(-ENOTSUPP);
le = hci_conn_hash_lookup_ba(hdev, LE_LINK, dst);
if (!le) {
le = hci_conn_hash_lookup_state(hdev, LE_LINK, BT_CONNECT);
if (le)
return ERR_PTR(-EBUSY);
le = hci_conn_add(hdev, LE_LINK, dst);
if (!le)
return ERR_PTR(-ENOMEM);
le->dst_type = bdaddr_to_le(dst_type);
hci_le_create_connection(le);
}
le->pending_sec_level = sec_level;
le->auth_type = auth_type;
hci_conn_hold(le);
return le;
}
static struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
u8 sec_level, u8 auth_type)
{
struct hci_conn *acl;
acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
if (!acl) {
acl = hci_conn_add(hdev, ACL_LINK, dst);
if (!acl)
return ERR_PTR(-ENOMEM);
}
hci_conn_hold(acl);
[Bluetooth] Enforce correct authentication requirements With the introduction of Security Mode 4 and Simple Pairing from the Bluetooth 2.1 specification it became mandatory that the initiator requires authentication and encryption before any L2CAP channel can be established. The only exception here is PSM 1 for the service discovery protocol (SDP). It is meant to be used without any encryption since it contains only public information. This is how Bluetooth 2.0 and before handle connections on PSM 1. For Bluetooth 2.1 devices the pairing procedure differentiates between no bonding, general bonding and dedicated bonding. The L2CAP layer wrongly uses always general bonding when creating new connections, but it should not do this for SDP connections. In this case the authentication requirement should be no bonding and the just-works model should be used, but in case of non-SDP connection it is required to use general bonding. If the new connection requires man-in-the-middle (MITM) protection, it also first wrongly creates an unauthenticated link key and then later on requests an upgrade to an authenticated link key to provide full MITM protection. With Simple Pairing the link key generation is an expensive operation (compared to Bluetooth 2.0 and before) and doing this twice during a connection setup causes a noticeable delay when establishing a new connection. This should be avoided to not regress from the expected Bluetooth 2.0 connection times. The authentication requirements are known up-front and so enforce them. To fulfill these requirements the hci_connect() function has been extended with an authentication requirement parameter that will be stored inside the connection information and can be retrieved by userspace at any time. This allows the correct IO capabilities exchange and results in the expected behavior. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2008-09-09 05:19:20 +00:00
if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
acl->sec_level = BT_SECURITY_LOW;
acl->pending_sec_level = sec_level;
[Bluetooth] Enforce correct authentication requirements With the introduction of Security Mode 4 and Simple Pairing from the Bluetooth 2.1 specification it became mandatory that the initiator requires authentication and encryption before any L2CAP channel can be established. The only exception here is PSM 1 for the service discovery protocol (SDP). It is meant to be used without any encryption since it contains only public information. This is how Bluetooth 2.0 and before handle connections on PSM 1. For Bluetooth 2.1 devices the pairing procedure differentiates between no bonding, general bonding and dedicated bonding. The L2CAP layer wrongly uses always general bonding when creating new connections, but it should not do this for SDP connections. In this case the authentication requirement should be no bonding and the just-works model should be used, but in case of non-SDP connection it is required to use general bonding. If the new connection requires man-in-the-middle (MITM) protection, it also first wrongly creates an unauthenticated link key and then later on requests an upgrade to an authenticated link key to provide full MITM protection. With Simple Pairing the link key generation is an expensive operation (compared to Bluetooth 2.0 and before) and doing this twice during a connection setup causes a noticeable delay when establishing a new connection. This should be avoided to not regress from the expected Bluetooth 2.0 connection times. The authentication requirements are known up-front and so enforce them. To fulfill these requirements the hci_connect() function has been extended with an authentication requirement parameter that will be stored inside the connection information and can be retrieved by userspace at any time. This allows the correct IO capabilities exchange and results in the expected behavior. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2008-09-09 05:19:20 +00:00
acl->auth_type = auth_type;
hci_acl_create_connection(acl);
[Bluetooth] Enforce correct authentication requirements With the introduction of Security Mode 4 and Simple Pairing from the Bluetooth 2.1 specification it became mandatory that the initiator requires authentication and encryption before any L2CAP channel can be established. The only exception here is PSM 1 for the service discovery protocol (SDP). It is meant to be used without any encryption since it contains only public information. This is how Bluetooth 2.0 and before handle connections on PSM 1. For Bluetooth 2.1 devices the pairing procedure differentiates between no bonding, general bonding and dedicated bonding. The L2CAP layer wrongly uses always general bonding when creating new connections, but it should not do this for SDP connections. In this case the authentication requirement should be no bonding and the just-works model should be used, but in case of non-SDP connection it is required to use general bonding. If the new connection requires man-in-the-middle (MITM) protection, it also first wrongly creates an unauthenticated link key and then later on requests an upgrade to an authenticated link key to provide full MITM protection. With Simple Pairing the link key generation is an expensive operation (compared to Bluetooth 2.0 and before) and doing this twice during a connection setup causes a noticeable delay when establishing a new connection. This should be avoided to not regress from the expected Bluetooth 2.0 connection times. The authentication requirements are known up-front and so enforce them. To fulfill these requirements the hci_connect() function has been extended with an authentication requirement parameter that will be stored inside the connection information and can be retrieved by userspace at any time. This allows the correct IO capabilities exchange and results in the expected behavior. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2008-09-09 05:19:20 +00:00
}
return acl;
}
static struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type,
bdaddr_t *dst, u8 sec_level, u8 auth_type)
{
struct hci_conn *acl;
struct hci_conn *sco;
acl = hci_connect_acl(hdev, dst, sec_level, auth_type);
if (IS_ERR(acl))
return acl;
sco = hci_conn_hash_lookup_ba(hdev, type, dst);
if (!sco) {
sco = hci_conn_add(hdev, type, dst);
if (!sco) {
hci_conn_put(acl);
return ERR_PTR(-ENOMEM);
}
}
acl->link = sco;
sco->link = acl;
hci_conn_hold(sco);
if (acl->state == BT_CONNECTED &&
(sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
/* defer SCO setup until mode change completed */
set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
return sco;
}
hci_sco_setup(acl, 0x00);
}
return sco;
}
/* Create SCO, ACL or LE connection. */
struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst,
__u8 dst_type, __u8 sec_level, __u8 auth_type)
{
BT_DBG("%s dst %pMR type 0x%x", hdev->name, dst, type);
switch (type) {
case LE_LINK:
return hci_connect_le(hdev, dst, dst_type, sec_level, auth_type);
case ACL_LINK:
return hci_connect_acl(hdev, dst, sec_level, auth_type);
case SCO_LINK:
case ESCO_LINK:
return hci_connect_sco(hdev, type, dst, sec_level, auth_type);
}
return ERR_PTR(-EINVAL);
}
/* Check link security requirement */
int hci_conn_check_link_mode(struct hci_conn *conn)
{
BT_DBG("hcon %p", conn);
if (hci_conn_ssp_enabled(conn) && !(conn->link_mode & HCI_LM_ENCRYPT))
return 0;
return 1;
}
/* Authenticate remote device */
static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
{
BT_DBG("hcon %p", conn);
if (conn->pending_sec_level > sec_level)
sec_level = conn->pending_sec_level;
if (sec_level > conn->sec_level)
conn->pending_sec_level = sec_level;
else if (conn->link_mode & HCI_LM_AUTH)
return 1;
/* Make sure we preserve an existing MITM requirement*/
auth_type |= (conn->auth_type & 0x01);
conn->auth_type = auth_type;
if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
struct hci_cp_auth_requested cp;
/* encrypt must be pending if auth is also pending */
set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
cp.handle = cpu_to_le16(conn->handle);
hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
sizeof(cp), &cp);
if (conn->key_type != 0xff)
set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
}
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
return 0;
}
/* Encrypt the the link */
static void hci_conn_encrypt(struct hci_conn *conn)
{
BT_DBG("hcon %p", conn);
if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
struct hci_cp_set_conn_encrypt cp;
cp.handle = cpu_to_le16(conn->handle);
cp.encrypt = 0x01;
hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
&cp);
}
}
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
/* Enable security */
int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
{
BT_DBG("hcon %p", conn);
if (conn->type == LE_LINK)
return smp_conn_security(conn, sec_level);
/* For sdp we don't need the link key. */
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
if (sec_level == BT_SECURITY_SDP)
return 1;
/* For non 2.1 devices and low security level we don't need the link
key. */
if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
return 1;
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
/* For other security levels we need the link key. */
if (!(conn->link_mode & HCI_LM_AUTH))
goto auth;
/* An authenticated combination key has sufficient security for any
security level. */
if (conn->key_type == HCI_LK_AUTH_COMBINATION)
goto encrypt;
/* An unauthenticated combination key has sufficient security for
security level 1 and 2. */
if (conn->key_type == HCI_LK_UNAUTH_COMBINATION &&
(sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
goto encrypt;
/* A combination key has always sufficient security for the security
levels 1 or 2. High security level requires the combination key
is generated using maximum PIN code length (16).
For pre 2.1 units. */
if (conn->key_type == HCI_LK_COMBINATION &&
(sec_level != BT_SECURITY_HIGH || conn->pin_length == 16))
goto encrypt;
auth:
if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
return 0;
if (!hci_conn_auth(conn, sec_level, auth_type))
return 0;
encrypt:
if (conn->link_mode & HCI_LM_ENCRYPT)
return 1;
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
hci_conn_encrypt(conn);
return 0;
}
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
EXPORT_SYMBOL(hci_conn_security);
/* Check secure link requirement */
int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
{
BT_DBG("hcon %p", conn);
if (sec_level != BT_SECURITY_HIGH)
return 1; /* Accept if non-secure is required */
if (conn->sec_level == BT_SECURITY_HIGH)
return 1;
return 0; /* Reject not secure link */
}
EXPORT_SYMBOL(hci_conn_check_secure);
/* Change link key */
int hci_conn_change_link_key(struct hci_conn *conn)
{
BT_DBG("hcon %p", conn);
if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
struct hci_cp_change_conn_link_key cp;
cp.handle = cpu_to_le16(conn->handle);
hci_send_cmd(conn->hdev, HCI_OP_CHANGE_CONN_LINK_KEY,
sizeof(cp), &cp);
}
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
return 0;
}
/* Switch role */
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
{
BT_DBG("hcon %p", conn);
if (!role && conn->link_mode & HCI_LM_MASTER)
return 1;
if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
struct hci_cp_switch_role cp;
bacpy(&cp.bdaddr, &conn->dst);
cp.role = role;
hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
}
Bluetooth: Add enhanced security model for Simple Pairing The current security model is based around the flags AUTH, ENCRYPT and SECURE. Starting with support for the Bluetooth 2.1 specification this is no longer sufficient. The different security levels are now defined as SDP, LOW, MEDIUM and SECURE. Previously it was possible to set each security independently, but this actually doesn't make a lot of sense. For Bluetooth the encryption depends on a previous successful authentication. Also you can only update your existing link key if you successfully created at least one before. And of course the update of link keys without having proper encryption in place is a security issue. The new security levels from the Bluetooth 2.1 specification are now used internally. All old settings are mapped to the new values and this way it ensures that old applications still work. The only limitation is that it is no longer possible to set authentication without also enabling encryption. No application should have done this anyway since this is actually a security issue. Without encryption the integrity of the authentication can't be guaranteed. As default for a new L2CAP or RFCOMM connection, the LOW security level is used. The only exception here are the service discovery sessions on PSM 1 where SDP level is used. To have similar security strength as with a Bluetooth 2.0 and before combination key, the MEDIUM level should be used. This is according to the Bluetooth specification. The MEDIUM level will not require any kind of man-in-the-middle (MITM) protection. Only the HIGH security level will require this. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-01-15 20:58:04 +00:00
return 0;
}
EXPORT_SYMBOL(hci_conn_switch_role);
/* Enter active mode */
void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
{
struct hci_dev *hdev = conn->hdev;
BT_DBG("hcon %p mode %d", conn, conn->mode);
if (test_bit(HCI_RAW, &hdev->flags))
return;
if (conn->mode != HCI_CM_SNIFF)
goto timer;
if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
goto timer;
if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
struct hci_cp_exit_sniff_mode cp;
cp.handle = cpu_to_le16(conn->handle);
hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
}
timer:
if (hdev->idle_timeout > 0)
mod_timer(&conn->idle_timer,
jiffies + msecs_to_jiffies(hdev->idle_timeout));
}
/* Drop all connection on the device */
void hci_conn_hash_flush(struct hci_dev *hdev)
{
struct hci_conn_hash *h = &hdev->conn_hash;
Bluetooth: Use list _safe deleting from conn_hash_list Use list_for_each_entry_safe which is safe version against removal of list entry. Otherwise we remove hci_conn element and reference next element which result in accessing LIST_POISON. [ 95.571834] Bluetooth: unknown link type 127 [ 95.578349] BUG: unable to handle kernel paging request at 20002000 [ 95.580236] IP: [<20002000>] 0x20001fff [ 95.580763] *pde = 00000000 [ 95.581196] Oops: 0000 [#1] SMP ... [ 95.582298] Pid: 3355, comm: hciconfig Tainted: G O 3.2.0-VirttualBox [ 95.582298] EIP: 0060:[<20002000>] EFLAGS: 00210206 CPU: 0 [ 95.582298] EIP is at 0x20002000 ... [ 95.582298] Call Trace: [ 95.582298] [<f8231ab6>] ? hci_conn_hash_flush+0x76/0xf0 [bluetooth] [ 95.582298] [<f822bcb1>] hci_dev_do_close+0xc1/0x2e0 [bluetooth] [ 95.582298] [<f822d679>] ? hci_dev_get+0x69/0xb0 [bluetooth] [ 95.582298] [<f822e1da>] hci_dev_close+0x2a/0x50 [bluetooth] [ 95.582298] [<f824102f>] hci_sock_ioctl+0x1af/0x3f0 [bluetooth] [ 95.582298] [<c11153ea>] ? handle_pte_fault+0x8a/0x8f0 [ 95.582298] [<c146becf>] sock_ioctl+0x5f/0x260 [ 95.582298] [<c146be70>] ? sock_fasync+0x90/0x90 [ 95.582298] [<c1152b33>] do_vfs_ioctl+0x83/0x5b0 [ 95.582298] [<c1563f87>] ? do_page_fault+0x297/0x500 [ 95.582298] [<c1563cf0>] ? spurious_fault+0xd0/0xd0 [ 95.582298] [<c107165b>] ? up_read+0x1b/0x30 [ 95.582298] [<c1563f87>] ? do_page_fault+0x297/0x500 [ 95.582298] [<c100aa9f>] ? init_fpu+0xef/0x160 [ 95.582298] [<c15617c0>] ? do_debug+0x180/0x180 [ 95.582298] [<c100a958>] ? fpu_finit+0x28/0x80 [ 95.582298] [<c11530e7>] sys_ioctl+0x87/0x90 [ 95.582298] [<c156795f>] sysenter_do_call+0x12/0x38 ... Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2012-02-02 08:32:17 +00:00
struct hci_conn *c, *n;
BT_DBG("hdev %s", hdev->name);
Bluetooth: Use list _safe deleting from conn_hash_list Use list_for_each_entry_safe which is safe version against removal of list entry. Otherwise we remove hci_conn element and reference next element which result in accessing LIST_POISON. [ 95.571834] Bluetooth: unknown link type 127 [ 95.578349] BUG: unable to handle kernel paging request at 20002000 [ 95.580236] IP: [<20002000>] 0x20001fff [ 95.580763] *pde = 00000000 [ 95.581196] Oops: 0000 [#1] SMP ... [ 95.582298] Pid: 3355, comm: hciconfig Tainted: G O 3.2.0-VirttualBox [ 95.582298] EIP: 0060:[<20002000>] EFLAGS: 00210206 CPU: 0 [ 95.582298] EIP is at 0x20002000 ... [ 95.582298] Call Trace: [ 95.582298] [<f8231ab6>] ? hci_conn_hash_flush+0x76/0xf0 [bluetooth] [ 95.582298] [<f822bcb1>] hci_dev_do_close+0xc1/0x2e0 [bluetooth] [ 95.582298] [<f822d679>] ? hci_dev_get+0x69/0xb0 [bluetooth] [ 95.582298] [<f822e1da>] hci_dev_close+0x2a/0x50 [bluetooth] [ 95.582298] [<f824102f>] hci_sock_ioctl+0x1af/0x3f0 [bluetooth] [ 95.582298] [<c11153ea>] ? handle_pte_fault+0x8a/0x8f0 [ 95.582298] [<c146becf>] sock_ioctl+0x5f/0x260 [ 95.582298] [<c146be70>] ? sock_fasync+0x90/0x90 [ 95.582298] [<c1152b33>] do_vfs_ioctl+0x83/0x5b0 [ 95.582298] [<c1563f87>] ? do_page_fault+0x297/0x500 [ 95.582298] [<c1563cf0>] ? spurious_fault+0xd0/0xd0 [ 95.582298] [<c107165b>] ? up_read+0x1b/0x30 [ 95.582298] [<c1563f87>] ? do_page_fault+0x297/0x500 [ 95.582298] [<c100aa9f>] ? init_fpu+0xef/0x160 [ 95.582298] [<c15617c0>] ? do_debug+0x180/0x180 [ 95.582298] [<c100a958>] ? fpu_finit+0x28/0x80 [ 95.582298] [<c11530e7>] sys_ioctl+0x87/0x90 [ 95.582298] [<c156795f>] sysenter_do_call+0x12/0x38 ... Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2012-02-02 08:32:17 +00:00
list_for_each_entry_safe(c, n, &h->list, list) {
c->state = BT_CLOSED;
hci_proto_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
hci_conn_del(c);
}
}
/* Check pending connect attempts */
void hci_conn_check_pending(struct hci_dev *hdev)
{
struct hci_conn *conn;
BT_DBG("hdev %s", hdev->name);
hci_dev_lock(hdev);
conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
if (conn)
hci_acl_create_connection(conn);
hci_dev_unlock(hdev);
}
void hci_conn_hold_device(struct hci_conn *conn)
{
atomic_inc(&conn->devref);
}
EXPORT_SYMBOL(hci_conn_hold_device);
void hci_conn_put_device(struct hci_conn *conn)
{
if (atomic_dec_and_test(&conn->devref))
hci_conn_del_sysfs(conn);
}
EXPORT_SYMBOL(hci_conn_put_device);
int hci_get_conn_list(void __user *arg)
{
struct hci_conn *c;
struct hci_conn_list_req req, *cl;
struct hci_conn_info *ci;
struct hci_dev *hdev;
int n = 0, size, err;
if (copy_from_user(&req, arg, sizeof(req)))
return -EFAULT;
if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
return -EINVAL;
size = sizeof(req) + req.conn_num * sizeof(*ci);
cl = kmalloc(size, GFP_KERNEL);
if (!cl)
return -ENOMEM;
hdev = hci_dev_get(req.dev_id);
if (!hdev) {
kfree(cl);
return -ENODEV;
}
ci = cl->conn_info;
hci_dev_lock(hdev);
list_for_each_entry(c, &hdev->conn_hash.list, list) {
bacpy(&(ci + n)->bdaddr, &c->dst);
(ci + n)->handle = c->handle;
(ci + n)->type = c->type;
(ci + n)->out = c->out;
(ci + n)->state = c->state;
(ci + n)->link_mode = c->link_mode;
if (++n >= req.conn_num)
break;
}
hci_dev_unlock(hdev);
cl->dev_id = hdev->id;
cl->conn_num = n;
size = sizeof(req) + n * sizeof(*ci);
hci_dev_put(hdev);
err = copy_to_user(arg, cl, size);
kfree(cl);
return err ? -EFAULT : 0;
}
int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
{
struct hci_conn_info_req req;
struct hci_conn_info ci;
struct hci_conn *conn;
char __user *ptr = arg + sizeof(req);
if (copy_from_user(&req, arg, sizeof(req)))
return -EFAULT;
hci_dev_lock(hdev);
conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
if (conn) {
bacpy(&ci.bdaddr, &conn->dst);
ci.handle = conn->handle;
ci.type = conn->type;
ci.out = conn->out;
ci.state = conn->state;
ci.link_mode = conn->link_mode;
}
hci_dev_unlock(hdev);
if (!conn)
return -ENOENT;
return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
}
int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
{
struct hci_auth_info_req req;
struct hci_conn *conn;
if (copy_from_user(&req, arg, sizeof(req)))
return -EFAULT;
hci_dev_lock(hdev);
conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
if (conn)
req.type = conn->auth_type;
hci_dev_unlock(hdev);
if (!conn)
return -ENOENT;
return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
}
struct hci_chan *hci_chan_create(struct hci_conn *conn)
{
struct hci_dev *hdev = conn->hdev;
struct hci_chan *chan;
BT_DBG("%s hcon %p", hdev->name, conn);
chan = kzalloc(sizeof(struct hci_chan), GFP_KERNEL);
if (!chan)
return NULL;
chan->conn = conn;
skb_queue_head_init(&chan->data_q);
chan->state = BT_CONNECTED;
list_add_rcu(&chan->list, &conn->chan_list);
return chan;
}
void hci_chan_del(struct hci_chan *chan)
{
struct hci_conn *conn = chan->conn;
struct hci_dev *hdev = conn->hdev;
BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
list_del_rcu(&chan->list);
synchronize_rcu();
hci_conn_put(conn);
skb_queue_purge(&chan->data_q);
kfree(chan);
}
void hci_chan_list_flush(struct hci_conn *conn)
{
struct hci_chan *chan, *n;
BT_DBG("hcon %p", conn);
list_for_each_entry_safe(chan, n, &conn->chan_list, list)
hci_chan_del(chan);
}
static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
__u16 handle)
{
struct hci_chan *hchan;
list_for_each_entry(hchan, &hcon->chan_list, list) {
if (hchan->handle == handle)
return hchan;
}
return NULL;
}
struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
{
struct hci_conn_hash *h = &hdev->conn_hash;
struct hci_conn *hcon;
struct hci_chan *hchan = NULL;
rcu_read_lock();
list_for_each_entry_rcu(hcon, &h->list, list) {
hchan = __hci_chan_lookup_handle(hcon, handle);
if (hchan)
break;
}
rcu_read_unlock();
return hchan;
}