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References: <cover.1686589290.git.pav@iki.fi> <d579997e06d68153a5630aba1ee9f2854d8b0cb4.1686589290.git.pav@iki.fi>
In-Reply-To: <d579997e06d68153a5630aba1ee9f2854d8b0cb4.1686589290.git.pav@iki.fi>
From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Tue, 13 Jun 2023 12:04:02 -0700
Message-ID: <CABBYNZ+B-5xz8BLB31KOEUhA7jWWfsMQmDF+YgPXrP1O0Ox1Ng@mail.gmail.com>
Subject: Re: [PATCH v2 1/3] Bluetooth: use RCU for hci_conn_params and iterate
 safely in hci_sync
To:     Pauli Virtanen <pav@iki.fi>
Cc:     linux-bluetooth@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

Hi Pauli,

On Tue, Jun 13, 2023 at 11:17=E2=80=AFAM Pauli Virtanen <pav@iki.fi> wrote:
>
> hci_update_accept_list_sync iterates over hdev->pend_le_conns and
> hdev->pend_le_reports, and waits for controller events in the loop body,
> without holding hdev lock.
>
> Meanwhile, these lists and the items may be modified e.g. by
> le_scan_cleanup.  This can invalidate the list cursor in the ongoing
> iterations, resulting to invalid behavior (eg use-after-free).
>
> Use RCU for the hci_conn_params action lists. Since the loop bodies in
> hci_sync block and we cannot use RCU for the whole loop, add
> hci_conn_params.add_pending to keep track which items are left. Copy
> data to avoid needing lock on hci_conn_params. Only the flags field is
> written from elsewhere, so READ_ONCE/WRITE_ONCE should guarantee we read
> valid values.
>
> Free params everywhere with hci_conn_params_free so the cleanup is
> guaranteed to be done properly.
>
> This fixes the following, which can be triggered at least by changing
> hci_le_set_cig_params to always return false, and running BlueZ
> iso-tester, which causes connections to be created and dropped fast:
>
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> BUG: KASAN: slab-use-after-free in hci_update_passive_scan_sync (net/blue=
tooth/hci_sync.c:2536 net/bluetooth/hci_sync.c:2723 net/bluetooth/hci_sync.=
c:2841)
> Read of size 8 at addr ffff888001265018 by task kworker/u3:0/32
>
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38 04=
/01/2014
> Workqueue: hci0 hci_cmd_sync_work
> Call Trace:
> <TASK>
> dump_stack_lvl (./arch/x86/include/asm/irqflags.h:134 lib/dump_stack.c:10=
7)
> print_report (mm/kasan/report.c:320 mm/kasan/report.c:430)
> ? __virt_addr_valid (./include/linux/mmzone.h:1915 ./include/linux/mmzone=
.h:2011 arch/x86/mm/physaddr.c:65)
> ? hci_update_passive_scan_sync (net/bluetooth/hci_sync.c:2536 net/bluetoo=
th/hci_sync.c:2723 net/bluetooth/hci_sync.c:2841)
> kasan_report (mm/kasan/report.c:538)
> ? hci_update_passive_scan_sync (net/bluetooth/hci_sync.c:2536 net/bluetoo=
th/hci_sync.c:2723 net/bluetooth/hci_sync.c:2841)
> hci_update_passive_scan_sync (net/bluetooth/hci_sync.c:2536 net/bluetooth=
/hci_sync.c:2723 net/bluetooth/hci_sync.c:2841)
> ? __pfx_hci_update_passive_scan_sync (net/bluetooth/hci_sync.c:2780)
> ? mutex_lock (kernel/locking/mutex.c:282)
> ? __pfx_mutex_lock (kernel/locking/mutex.c:282)
> ? __pfx_mutex_unlock (kernel/locking/mutex.c:538)
> ? __pfx_update_passive_scan_sync (net/bluetooth/hci_sync.c:2861)
> hci_cmd_sync_work (net/bluetooth/hci_sync.c:306)
> process_one_work (./arch/x86/include/asm/preempt.h:27 kernel/workqueue.c:=
2399)
> worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2538)
> ? __pfx_worker_thread (kernel/workqueue.c:2480)
> kthread (kernel/kthread.c:376)
> ? __pfx_kthread (kernel/kthread.c:331)
> ret_from_fork (arch/x86/entry/entry_64.S:314)
> </TASK>
>
> Allocated by task 31:
> kasan_save_stack (mm/kasan/common.c:46)
> kasan_set_track (mm/kasan/common.c:52)
> __kasan_kmalloc (mm/kasan/common.c:374 mm/kasan/common.c:383)
> hci_conn_params_add (./include/linux/slab.h:580 ./include/linux/slab.h:72=
0 net/bluetooth/hci_core.c:2277)
> hci_connect_le_scan (net/bluetooth/hci_conn.c:1419 net/bluetooth/hci_conn=
.c:1589)
> hci_connect_cis (net/bluetooth/hci_conn.c:2266)
> iso_connect_cis (net/bluetooth/iso.c:390)
> iso_sock_connect (net/bluetooth/iso.c:899)
> __sys_connect (net/socket.c:2003 net/socket.c:2020)
> __x64_sys_connect (net/socket.c:2027)
> do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
> entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
>
> Freed by task 15:
> kasan_save_stack (mm/kasan/common.c:46)
> kasan_set_track (mm/kasan/common.c:52)
> kasan_save_free_info (mm/kasan/generic.c:523)
> __kasan_slab_free (mm/kasan/common.c:238 mm/kasan/common.c:200 mm/kasan/c=
ommon.c:244)
> __kmem_cache_free (mm/slub.c:1807 mm/slub.c:3787 mm/slub.c:3800)
> hci_conn_params_del (net/bluetooth/hci_core.c:2323)
> le_scan_cleanup (net/bluetooth/hci_conn.c:202)
> process_one_work (./arch/x86/include/asm/preempt.h:27 kernel/workqueue.c:=
2399)
> worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2538)
> kthread (kernel/kthread.c:376)
> ret_from_fork (arch/x86/entry/entry_64.S:314)
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>
> Fixes: e8907f76544f ("Bluetooth: hci_sync: Make use of hci_cmd_sync_queue=
 set 3")
> Signed-off-by: Pauli Virtanen <pav@iki.fi>
> ---
>
> Notes:
>     v2: use RCU

Really nice work.

>  include/net/bluetooth/hci_core.h |  5 ++
>  net/bluetooth/hci_conn.c         |  9 ++--
>  net/bluetooth/hci_core.c         | 34 +++++++++---
>  net/bluetooth/hci_event.c        | 12 ++---
>  net/bluetooth/hci_sync.c         | 93 ++++++++++++++++++++++++++++----
>  net/bluetooth/mgmt.c             | 30 +++++------
>  6 files changed, 141 insertions(+), 42 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci=
_core.h
> index 683666ea210c..8c6ac6d29c62 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -822,6 +822,8 @@ struct hci_conn_params {
>
>         struct hci_conn *conn;
>         bool explicit_connect;
> +       /* Accessed without hdev->lock: */
> +       bool add_pending;

That is the only part that Im a little uncorfortable with, are we
doing this because we can't do use the cmd_sync while holding RCU
lock? In that case couldn't we perhaps update the list? Also we could
perhaps add it as a flag rather than a separated field.

>         hci_conn_flags_t flags;
>         u8  privacy_mode;
>  };
> @@ -1605,6 +1607,9 @@ struct hci_conn_params *hci_conn_params_add(struct =
hci_dev *hdev,
>                                             bdaddr_t *addr, u8 addr_type)=
;
>  void hci_conn_params_del(struct hci_dev *hdev, bdaddr_t *addr, u8 addr_t=
ype);
>  void hci_conn_params_clear_disabled(struct hci_dev *hdev);
> +void hci_conn_params_free(struct hci_conn_params *param);
> +void hci_conn_params_set_pending(struct hci_conn_params *param,
> +                                struct list_head *list);
>
>  struct hci_conn_params *hci_pend_le_action_lookup(struct list_head *list=
,
>                                                   bdaddr_t *addr,
> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
> index 7d4941e6dbdf..ae9a35d1405b 100644
> --- a/net/bluetooth/hci_conn.c
> +++ b/net/bluetooth/hci_conn.c
> @@ -118,7 +118,7 @@ static void hci_connect_le_scan_cleanup(struct hci_co=
nn *conn, u8 status)
>          */
>         params->explicit_connect =3D false;
>
> -       list_del_init(&params->action);
> +       hci_conn_params_set_pending(params, NULL);
>
>         switch (params->auto_connect) {
>         case HCI_AUTO_CONN_EXPLICIT:
> @@ -127,10 +127,10 @@ static void hci_connect_le_scan_cleanup(struct hci_=
conn *conn, u8 status)
>                 return;
>         case HCI_AUTO_CONN_DIRECT:
>         case HCI_AUTO_CONN_ALWAYS:
> -               list_add(&params->action, &hdev->pend_le_conns);
> +               hci_conn_params_set_pending(params, &hdev->pend_le_conns)=
;
>                 break;
>         case HCI_AUTO_CONN_REPORT:
> -               list_add(&params->action, &hdev->pend_le_reports);
> +               hci_conn_params_set_pending(params, &hdev->pend_le_report=
s);
>                 break;
>         default:
>                 break;
> @@ -1435,8 +1435,7 @@ static int hci_explicit_conn_params_set(struct hci_=
dev *hdev,
>         if (params->auto_connect =3D=3D HCI_AUTO_CONN_DISABLED ||
>             params->auto_connect =3D=3D HCI_AUTO_CONN_REPORT ||
>             params->auto_connect =3D=3D HCI_AUTO_CONN_EXPLICIT) {
> -               list_del_init(&params->action);
> -               list_add(&params->action, &hdev->pend_le_conns);
> +               hci_conn_params_set_pending(params, &hdev->pend_le_conns)=
;

Id just follow the name convention e.g. hci_conn_params_list_add,
hci_conn_params_list_del, etc.

>         }
>
>         params->explicit_connect =3D true;
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 48917c68358d..7992a61fe1fd 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -2249,21 +2249,41 @@ struct hci_conn_params *hci_conn_params_lookup(st=
ruct hci_dev *hdev,
>         return NULL;
>  }
>
> -/* This function requires the caller holds hdev->lock */
> +/* This function requires the caller holds hdev->lock or rcu_read_lock *=
/
>  struct hci_conn_params *hci_pend_le_action_lookup(struct list_head *list=
,
>                                                   bdaddr_t *addr, u8 addr=
_type)
>  {
>         struct hci_conn_params *param;
>
> -       list_for_each_entry(param, list, action) {
> +       rcu_read_lock();
> +
> +       list_for_each_entry_rcu(param, list, action) {
>                 if (bacmp(&param->addr, addr) =3D=3D 0 &&
> -                   param->addr_type =3D=3D addr_type)
> +                   param->addr_type =3D=3D addr_type) {
> +                       rcu_read_unlock();
>                         return param;
> +               }
>         }
>
> +       rcu_read_unlock();
> +
>         return NULL;
>  }
>
> +/* This function requires the caller holds hdev->lock */
> +void hci_conn_params_set_pending(struct hci_conn_params *param,
> +                                struct list_head *list)
> +{
> +       if (!list_empty(&param->action)) {
> +               list_del_rcu(&param->action);
> +               synchronize_rcu();
> +               INIT_LIST_HEAD(&param->action);
> +       }
> +
> +       if (list)
> +               list_add_rcu(&param->action, list);
> +}
> +
>  /* This function requires the caller holds hdev->lock */
>  struct hci_conn_params *hci_conn_params_add(struct hci_dev *hdev,
>                                             bdaddr_t *addr, u8 addr_type)
> @@ -2297,14 +2317,15 @@ struct hci_conn_params *hci_conn_params_add(struc=
t hci_dev *hdev,
>         return params;
>  }
>
> -static void hci_conn_params_free(struct hci_conn_params *params)
> +void hci_conn_params_free(struct hci_conn_params *params)
>  {
> +       hci_conn_params_set_pending(params, NULL);
> +
>         if (params->conn) {
>                 hci_conn_drop(params->conn);
>                 hci_conn_put(params->conn);
>         }
>
> -       list_del(&params->action);
>         list_del(&params->list);
>         kfree(params);
>  }
> @@ -2342,8 +2363,7 @@ void hci_conn_params_clear_disabled(struct hci_dev =
*hdev)
>                         continue;
>                 }
>
> -               list_del(&params->list);
> -               kfree(params);
> +               hci_conn_params_free(params);
>         }
>
>         BT_DBG("All LE disabled connection parameters were removed");
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 7c199f7361f7..8187c9f827fa 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -1564,7 +1564,7 @@ static u8 hci_cc_le_set_privacy_mode(struct hci_dev=
 *hdev, void *data,
>
>         params =3D hci_conn_params_lookup(hdev, &cp->bdaddr, cp->bdaddr_t=
ype);
>         if (params)
> -               params->privacy_mode =3D cp->mode;
> +               WRITE_ONCE(params->privacy_mode, cp->mode);
>
>         hci_dev_unlock(hdev);
>
> @@ -2804,8 +2804,8 @@ static void hci_cs_disconnect(struct hci_dev *hdev,=
 u8 status)
>
>                 case HCI_AUTO_CONN_DIRECT:
>                 case HCI_AUTO_CONN_ALWAYS:
> -                       list_del_init(&params->action);
> -                       list_add(&params->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_conns)=
;
>                         break;
>
>                 default:
> @@ -3423,8 +3423,8 @@ static void hci_disconn_complete_evt(struct hci_dev=
 *hdev, void *data,
>
>                 case HCI_AUTO_CONN_DIRECT:
>                 case HCI_AUTO_CONN_ALWAYS:
> -                       list_del_init(&params->action);
> -                       list_add(&params->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_conns)=
;
>                         hci_update_passive_scan(hdev);
>                         break;
>
> @@ -5972,7 +5972,7 @@ static void le_conn_complete_evt(struct hci_dev *hd=
ev, u8 status,
>         params =3D hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn-=
>dst,
>                                            conn->dst_type);
>         if (params) {
> -               list_del_init(&params->action);
> +               hci_conn_params_set_pending(params, NULL);
>                 if (params->conn) {
>                         hci_conn_drop(params->conn);
>                         hci_conn_put(params->conn);
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 97da5bcaa904..da12e286ee64 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -2160,15 +2160,23 @@ static int hci_le_del_accept_list_sync(struct hci=
_dev *hdev,
>         return 0;
>  }
>
> +struct conn_params {
> +       bdaddr_t addr;
> +       u8 addr_type;
> +       hci_conn_flags_t flags;
> +       u8 privacy_mode;
> +};
> +
>  /* Adds connection to resolve list if needed.
>   * Setting params to NULL programs local hdev->irk
>   */
>  static int hci_le_add_resolve_list_sync(struct hci_dev *hdev,
> -                                       struct hci_conn_params *params)
> +                                       struct conn_params *params)
>  {
>         struct hci_cp_le_add_to_resolv_list cp;
>         struct smp_irk *irk;
>         struct bdaddr_list_with_irk *entry;
> +       struct hci_conn_params *p;
>
>         if (!use_ll_privacy(hdev))
>                 return 0;
> @@ -2203,6 +2211,16 @@ static int hci_le_add_resolve_list_sync(struct hci=
_dev *hdev,
>         /* Default privacy mode is always Network */
>         params->privacy_mode =3D HCI_NETWORK_PRIVACY;
>
> +       rcu_read_lock();
> +       p =3D hci_pend_le_action_lookup(&hdev->pend_le_conns,
> +                                     &params->addr, params->addr_type);
> +       if (!p)
> +               p =3D hci_pend_le_action_lookup(&hdev->pend_le_reports,
> +                                             &params->addr, params->addr=
_type);
> +       if (p)
> +               WRITE_ONCE(p->privacy_mode, HCI_NETWORK_PRIVACY);
> +       rcu_read_unlock();
> +
>  done:
>         if (hci_dev_test_flag(hdev, HCI_PRIVACY))
>                 memcpy(cp.local_irk, hdev->irk, 16);
> @@ -2215,7 +2233,7 @@ static int hci_le_add_resolve_list_sync(struct hci_=
dev *hdev,
>
>  /* Set Device Privacy Mode. */
>  static int hci_le_set_privacy_mode_sync(struct hci_dev *hdev,
> -                                       struct hci_conn_params *params)
> +                                       struct conn_params *params)
>  {
>         struct hci_cp_le_set_privacy_mode cp;
>         struct smp_irk *irk;
> @@ -2240,6 +2258,8 @@ static int hci_le_set_privacy_mode_sync(struct hci_=
dev *hdev,
>         bacpy(&cp.bdaddr, &irk->bdaddr);
>         cp.mode =3D HCI_DEVICE_PRIVACY;
>
> +       /* Note: params->privacy_mode is not updated since it is a copy *=
/
> +
>         return __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_PRIVACY_MODE,
>                                      sizeof(cp), &cp, HCI_CMD_TIMEOUT);
>  }
> @@ -2249,7 +2269,7 @@ static int hci_le_set_privacy_mode_sync(struct hci_=
dev *hdev,
>   * properly set the privacy mode.
>   */
>  static int hci_le_add_accept_list_sync(struct hci_dev *hdev,
> -                                      struct hci_conn_params *params,
> +                                      struct conn_params *params,
>                                        u8 *num_entries)
>  {
>         struct hci_cp_le_add_to_accept_list cp;
> @@ -2447,6 +2467,51 @@ struct sk_buff *hci_read_local_oob_data_sync(struc=
t hci_dev *hdev,
>         return __hci_cmd_sync_sk(hdev, opcode, 0, NULL, 0, HCI_CMD_TIMEOU=
T, sk);
>  }
>
> +static void conn_params_add_iter_init(struct list_head *list)
> +{
> +       struct hci_conn_params *params;
> +
> +       rcu_read_lock();
> +
> +       list_for_each_entry_rcu(params, list, action)
> +               params->add_pending =3D true;
> +
> +       rcu_read_unlock();
> +}
> +
> +static bool conn_params_add_iter_next(struct list_head *list,
> +                                     struct conn_params *item)
> +{
> +       struct hci_conn_params *params;
> +
> +       rcu_read_lock();
> +
> +       list_for_each_entry_rcu(params, list, action) {
> +               if (!params->add_pending)
> +                       continue;
> +
> +               /* No hdev->lock, but: addr, addr_type are immutable.
> +                * privacy_mode is only written by us or in
> +                * hci_cc_le_set_privacy_mode that we wait for.
> +                * We should be idempotent so MGMT updating flags
> +                * while we are processing is OK.
> +                */
> +               bacpy(&item->addr, &params->addr);
> +               item->addr_type =3D params->addr_type;
> +               item->flags =3D READ_ONCE(params->flags);
> +               item->privacy_mode =3D READ_ONCE(params->privacy_mode);
> +
> +               params->add_pending =3D false;
> +
> +               rcu_read_unlock();
> +               return true;
> +       }
> +
> +       rcu_read_unlock();
> +
> +       return false;
> +}
> +
>  /* Device must not be scanning when updating the accept list.
>   *
>   * Update is done using the following sequence:
> @@ -2466,7 +2531,7 @@ struct sk_buff *hci_read_local_oob_data_sync(struct=
 hci_dev *hdev,
>   */
>  static u8 hci_update_accept_list_sync(struct hci_dev *hdev)
>  {
> -       struct hci_conn_params *params;
> +       struct conn_params params;
>         struct bdaddr_list *b, *t;
>         u8 num_entries =3D 0;
>         bool pend_conn, pend_report;
> @@ -2504,6 +2569,7 @@ static u8 hci_update_accept_list_sync(struct hci_de=
v *hdev)
>                 if (hci_conn_hash_lookup_le(hdev, &b->bdaddr, b->bdaddr_t=
ype))
>                         continue;
>
> +               /* Pointers not dereferenced, no locks needed */
>                 pend_conn =3D hci_pend_le_action_lookup(&hdev->pend_le_co=
nns,
>                                                       &b->bdaddr,
>                                                       b->bdaddr_type);
> @@ -2532,9 +2598,15 @@ static u8 hci_update_accept_list_sync(struct hci_d=
ev *hdev)
>          * available accept list entries in the controller, then
>          * just abort and return filer policy value to not use the
>          * accept list.
> +        *
> +        * The list and params may be mutated while we wait for events,
> +        * so use special iteration with copies.
>          */
> -       list_for_each_entry(params, &hdev->pend_le_conns, action) {
> -               err =3D hci_le_add_accept_list_sync(hdev, params, &num_en=
tries);
> +
> +       conn_params_add_iter_init(&hdev->pend_le_conns);
> +
> +       while (conn_params_add_iter_next(&hdev->pend_le_conns, &params)) =
{
> +               err =3D hci_le_add_accept_list_sync(hdev, &params, &num_e=
ntries);
>                 if (err)
>                         goto done;
>         }
> @@ -2543,8 +2615,11 @@ static u8 hci_update_accept_list_sync(struct hci_d=
ev *hdev)
>          * the list of pending reports and also add these to the
>          * accept list if there is still space. Abort if space runs out.
>          */
> -       list_for_each_entry(params, &hdev->pend_le_reports, action) {
> -               err =3D hci_le_add_accept_list_sync(hdev, params, &num_en=
tries);
> +
> +       conn_params_add_iter_init(&hdev->pend_le_reports);
> +
> +       while (conn_params_add_iter_next(&hdev->pend_le_reports, &params)=
) {
> +               err =3D hci_le_add_accept_list_sync(hdev, &params, &num_e=
ntries);
>                 if (err)
>                         goto done;
>         }
> @@ -4837,12 +4912,12 @@ static void hci_pend_le_actions_clear(struct hci_=
dev *hdev)
>         struct hci_conn_params *p;
>
>         list_for_each_entry(p, &hdev->le_conn_params, list) {
> +               hci_conn_params_set_pending(p, NULL);
>                 if (p->conn) {
>                         hci_conn_drop(p->conn);
>                         hci_conn_put(p->conn);
>                         p->conn =3D NULL;
>                 }
> -               list_del_init(&p->action);
>         }
>
>         BT_DBG("All LE pending actions cleared");
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index 61c8e1b8f3b0..b35b1c685b86 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -1303,15 +1303,15 @@ static void restart_le_actions(struct hci_dev *hd=
ev)
>                 /* Needed for AUTO_OFF case where might not "really"
>                  * have been powered off.
>                  */
> -               list_del_init(&p->action);
> +               hci_conn_params_set_pending(p, NULL);
>
>                 switch (p->auto_connect) {
>                 case HCI_AUTO_CONN_DIRECT:
>                 case HCI_AUTO_CONN_ALWAYS:
> -                       list_add(&p->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(p, &hdev->pend_le_con=
ns);
>                         break;
>                 case HCI_AUTO_CONN_REPORT:
> -                       list_add(&p->action, &hdev->pend_le_reports);
> +                       hci_conn_params_set_pending(p, &hdev->pend_le_rep=
orts);
>                         break;
>                 default:
>                         break;
> @@ -5175,7 +5175,7 @@ static int set_device_flags(struct sock *sk, struct=
 hci_dev *hdev, void *data,
>                 goto unlock;
>         }
>
> -       params->flags =3D current_flags;
> +       WRITE_ONCE(params->flags, current_flags);
>         status =3D MGMT_STATUS_SUCCESS;
>
>         /* Update passive scan if HCI_CONN_FLAG_DEVICE_PRIVACY
> @@ -7586,7 +7586,7 @@ static int hci_conn_params_set(struct hci_dev *hdev=
, bdaddr_t *addr,
>         if (params->auto_connect =3D=3D auto_connect)
>                 return 0;
>
> -       list_del_init(&params->action);
> +       hci_conn_params_set_pending(params, NULL);
>
>         switch (auto_connect) {
>         case HCI_AUTO_CONN_DISABLED:
> @@ -7595,18 +7595,22 @@ static int hci_conn_params_set(struct hci_dev *hd=
ev, bdaddr_t *addr,
>                  * connect to device, keep connecting.
>                  */
>                 if (params->explicit_connect)
> -                       list_add(&params->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_conns)=
;
>                 break;
>         case HCI_AUTO_CONN_REPORT:
>                 if (params->explicit_connect)
> -                       list_add(&params->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_conns)=
;
>                 else
> -                       list_add(&params->action, &hdev->pend_le_reports)=
;
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_report=
s);
>                 break;
>         case HCI_AUTO_CONN_DIRECT:
>         case HCI_AUTO_CONN_ALWAYS:
>                 if (!is_connected(hdev, addr, addr_type))
> -                       list_add(&params->action, &hdev->pend_le_conns);
> +                       hci_conn_params_set_pending(params,
> +                                                   &hdev->pend_le_conns)=
;
>                 break;
>         }
>
> @@ -7829,9 +7833,7 @@ static int remove_device(struct sock *sk, struct hc=
i_dev *hdev,
>                         goto unlock;
>                 }
>
> -               list_del(&params->action);
> -               list_del(&params->list);
> -               kfree(params);
> +               hci_conn_params_free(params);
>
>                 device_removed(sk, hdev, &cp->addr.bdaddr, cp->addr.type)=
;
>         } else {
> @@ -7862,9 +7864,7 @@ static int remove_device(struct sock *sk, struct hc=
i_dev *hdev,
>                                 p->auto_connect =3D HCI_AUTO_CONN_EXPLICI=
T;
>                                 continue;
>                         }
> -                       list_del(&p->action);
> -                       list_del(&p->list);
> -                       kfree(p);
> +                       hci_conn_params_free(p);
>                 }
>
>                 bt_dev_dbg(hdev, "All LE connection parameters were remov=
ed");
> --
> 2.40.1
>


--=20
Luiz Augusto von Dentz