Hi Luiz,
ma, 2025-06-02 kello 13:46 -0400, Luiz Augusto von Dentz kirjoitti:
> From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
>
> This uses a mutex to protect from concurrent access of mgmt_pending
> list which can cause crashes like:
>
> ==================================================================
> BUG: KASAN: slab-use-after-free in mgmt_remove_adv_monitor_complete+0xe5/0x540 net/bluetooth/mgmt.c:5405
> Read of size 8 at addr ffff888048891a18 by task kworker/u5:8/5333
>
> CPU: 0 UID: 0 PID: 5333 Comm: kworker/u5:8 Not tainted 6.15.0-rc5-syzkaller-00197-gea34704d6ad7 #0 PREEMPT(full)
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> Workqueue: hci0 hci_cmd_sync_work
> Call Trace:
> <TASK>
> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
> print_address_description mm/kasan/report.c:408 [inline]
> print_report+0xb4/0x290 mm/kasan/report.c:521
> kasan_report+0x118/0x150 mm/kasan/report.c:634
> mgmt_remove_adv_monitor_complete+0xe5/0x540 net/bluetooth/mgmt.c:5405
> hci_cmd_sync_work+0x25e/0x3a0 net/bluetooth/hci_sync.c:334
> process_one_work kernel/workqueue.c:3238 [inline]
> process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
> worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
> kthread+0x70e/0x8a0 kernel/kthread.c:464
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
> </TASK>
>
> Allocated by task 5702:
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
> poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
> __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
> kasan_kmalloc include/linux/kasan.h:260 [inline]
> __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
> kmalloc_noprof include/linux/slab.h:905 [inline]
> kzalloc_noprof include/linux/slab.h:1039 [inline]
> mgmt_pending_new+0x65/0x240 net/bluetooth/mgmt_util.c:252
> mgmt_pending_add+0x34/0x120 net/bluetooth/mgmt_util.c:279
> remove_adv_monitor+0x103/0x1b0 net/bluetooth/mgmt.c:5453
> hci_mgmt_cmd+0x9c6/0xef0 net/bluetooth/hci_sock.c:1712
> hci_sock_sendmsg+0x6ca/0xee0 net/bluetooth/hci_sock.c:1832
> sock_sendmsg_nosec net/socket.c:712 [inline]
> __sock_sendmsg+0x219/0x270 net/socket.c:727
> sock_write_iter+0x258/0x330 net/socket.c:1131
> new_sync_write fs/read_write.c:591 [inline]
> vfs_write+0x548/0xa90 fs/read_write.c:684
> ksys_write+0x145/0x250 fs/read_write.c:736
> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
> do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Freed by task 5700:
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
> kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
> poison_slab_object mm/kasan/common.c:247 [inline]
> __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
> kasan_slab_free include/linux/kasan.h:233 [inline]
> slab_free_hook mm/slub.c:2380 [inline]
> slab_free mm/slub.c:4642 [inline]
> kfree+0x193/0x440 mm/slub.c:4841
> mgmt_pending_foreach+0xc9/0x120 net/bluetooth/mgmt_util.c:242
> mgmt_index_removed+0x10d/0x2f0 net/bluetooth/mgmt.c:9362
> hci_sock_bind+0xbe9/0x1000 net/bluetooth/hci_sock.c:1307
> __sys_bind_socket net/socket.c:1810 [inline]
> __sys_bind+0x2c3/0x3e0 net/socket.c:1841
> __do_sys_bind net/socket.c:1846 [inline]
> __se_sys_bind net/socket.c:1844 [inline]
> __x64_sys_bind+0x7a/0x90 net/socket.c:1844
> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
> do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Fixes: a380b6cff1a2 ("Bluetooth: Add generic mgmt helper API")
> Closes: https://syzkaller.appspot.com/bug?extid=feb0dc579bbe30a13190
> Closes: https://syzkaller.appspot.com/bug?extid=0a7039d5d9986ff4ececi
> Closes: https://syzkaller.appspot.com/bug?extid=cc0cc52e7f43dc9e6df1
> Reported-by: syzbot+feb0dc579bbe30a13190@xxxxxxxxxxxxxxxxxxxxxxxxx
> Tested-by: syzbot+feb0dc579bbe30a13190@xxxxxxxxxxxxxxxxxxxxxxxxx
> Tested-by: syzbot+0a7039d5d9986ff4ecec@xxxxxxxxxxxxxxxxxxxxxxxxx
> Tested-by: syzbot+cc0cc52e7f43dc9e6df1@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx>
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
> ---
> include/net/bluetooth/hci_core.h | 1 +
> net/bluetooth/hci_core.c | 1 +
> net/bluetooth/mgmt.c | 101 +++++++++++++++----------------
> net/bluetooth/mgmt_util.c | 32 ++++++++--
> net/bluetooth/mgmt_util.h | 4 +-
> 5 files changed, 80 insertions(+), 59 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 2b261e74e2c4..b9ff0e825071 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -546,6 +546,7 @@ struct hci_dev {
> struct hci_conn_hash conn_hash;
>
> struct list_head mesh_pending;
> + struct mutex mgmt_pending_lock;
> struct list_head mgmt_pending;
> struct list_head reject_list;
> struct list_head accept_list;
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 04845ff3ad57..f197f5497043 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -2487,6 +2487,7 @@ struct hci_dev *hci_alloc_dev_priv(int sizeof_priv)
>
> mutex_init(&hdev->lock);
> mutex_init(&hdev->req_lock);
> + mutex_init(&hdev->mgmt_pending_lock);
>
> ida_init(&hdev->unset_handle_ida);
>
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index 14a9462fced5..7d9ed7db377f 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -1447,22 +1447,17 @@ static void settings_rsp(struct mgmt_pending_cmd *cmd, void *data)
>
> send_settings_rsp(cmd->sk, cmd->opcode, match->hdev);
>
> - list_del(&cmd->list);
> -
> if (match->sk == NULL) {
> match->sk = cmd->sk;
> sock_hold(match->sk);
> }
> -
> - mgmt_pending_free(cmd);
> }
>
> static void cmd_status_rsp(struct mgmt_pending_cmd *cmd, void *data)
> {
> u8 *status = data;
>
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode, *status);
> - mgmt_pending_remove(cmd);
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode, *status);
> }
>
> static void cmd_complete_rsp(struct mgmt_pending_cmd *cmd, void *data)
> @@ -1476,8 +1471,6 @@ static void cmd_complete_rsp(struct mgmt_pending_cmd *cmd, void *data)
>
> if (cmd->cmd_complete) {
> cmd->cmd_complete(cmd, match->mgmt_status);
> - mgmt_pending_remove(cmd);
> -
> return;
> }
>
> @@ -1486,13 +1479,13 @@ static void cmd_complete_rsp(struct mgmt_pending_cmd *cmd, void *data)
>
> static int generic_cmd_complete(struct mgmt_pending_cmd *cmd, u8 status)
> {
> - return mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, status,
> + return mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, status,
> cmd->param, cmd->param_len);
> }
>
> static int addr_cmd_complete(struct mgmt_pending_cmd *cmd, u8 status)
> {
> - return mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, status,
> + return mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, status,
> cmd->param, sizeof(struct mgmt_addr_info));
> }
>
> @@ -1532,7 +1525,7 @@ static void mgmt_set_discoverable_complete(struct hci_dev *hdev, void *data,
>
> if (err) {
> u8 mgmt_err = mgmt_status(err);
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode, mgmt_err);
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_err);
> hci_dev_clear_flag(hdev, HCI_LIMITED_DISCOVERABLE);
> goto done;
> }
> @@ -1707,7 +1700,7 @@ static void mgmt_set_connectable_complete(struct hci_dev *hdev, void *data,
>
> if (err) {
> u8 mgmt_err = mgmt_status(err);
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode, mgmt_err);
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_err);
> goto done;
> }
>
> @@ -1943,8 +1936,8 @@ static void set_ssp_complete(struct hci_dev *hdev, void *data, int err)
> new_settings(hdev, NULL);
> }
>
> - mgmt_pending_foreach(MGMT_OP_SET_SSP, hdev, cmd_status_rsp,
> - &mgmt_err);
> + mgmt_pending_foreach(MGMT_OP_SET_SSP, hdev, true,
> + cmd_status_rsp, &mgmt_err);
> return;
> }
>
> @@ -1954,7 +1947,7 @@ static void set_ssp_complete(struct hci_dev *hdev, void *data, int err)
> changed = hci_dev_test_and_clear_flag(hdev, HCI_SSP_ENABLED);
> }
>
> - mgmt_pending_foreach(MGMT_OP_SET_SSP, hdev, settings_rsp, &match);
> + mgmt_pending_foreach(MGMT_OP_SET_SSP, hdev, true, settings_rsp, &match);
>
> if (changed)
> new_settings(hdev, match.sk);
> @@ -2074,12 +2067,12 @@ static void set_le_complete(struct hci_dev *hdev, void *data, int err)
> bt_dev_dbg(hdev, "err %d", err);
>
> if (status) {
> - mgmt_pending_foreach(MGMT_OP_SET_LE, hdev, cmd_status_rsp,
> - &status);
> + mgmt_pending_foreach(MGMT_OP_SET_LE, hdev, true, cmd_status_rsp,
> + &status);
> return;
> }
>
> - mgmt_pending_foreach(MGMT_OP_SET_LE, hdev, settings_rsp, &match);
> + mgmt_pending_foreach(MGMT_OP_SET_LE, hdev, true, settings_rsp, &match);
>
> new_settings(hdev, match.sk);
>
> @@ -2138,7 +2131,7 @@ static void set_mesh_complete(struct hci_dev *hdev, void *data, int err)
> struct sock *sk = cmd->sk;
>
> if (status) {
> - mgmt_pending_foreach(MGMT_OP_SET_MESH_RECEIVER, hdev,
> + mgmt_pending_foreach(MGMT_OP_SET_MESH_RECEIVER, hdev, true,
> cmd_status_rsp, &status);
> return;
> }
> @@ -2638,7 +2631,7 @@ static void mgmt_class_complete(struct hci_dev *hdev, void *data, int err)
>
> bt_dev_dbg(hdev, "err %d", err);
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err), hdev->dev_class, 3);
>
> mgmt_pending_free(cmd);
> @@ -3427,7 +3420,7 @@ static int pairing_complete(struct mgmt_pending_cmd *cmd, u8 status)
> bacpy(&rp.addr.bdaddr, &conn->dst);
> rp.addr.type = link_to_bdaddr(conn->type, conn->dst_type);
>
> - err = mgmt_cmd_complete(cmd->sk, cmd->index, MGMT_OP_PAIR_DEVICE,
> + err = mgmt_cmd_complete(cmd->sk, cmd->hdev->id, MGMT_OP_PAIR_DEVICE,
> status, &rp, sizeof(rp));
>
> /* So we don't get further callbacks for this connection */
> @@ -5196,7 +5189,7 @@ static void mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev,
> hci_update_passive_scan(hdev);
> }
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(status), &rp, sizeof(rp));
> mgmt_pending_remove(cmd);
>
> @@ -5411,7 +5404,7 @@ static void mgmt_remove_adv_monitor_complete(struct hci_dev *hdev,
> if (!status)
> hci_update_passive_scan(hdev);
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(status), &rp, sizeof(rp));
> mgmt_pending_remove(cmd);
>
> @@ -5792,7 +5785,7 @@ static void start_discovery_complete(struct hci_dev *hdev, void *data, int err)
> cmd != pending_find(MGMT_OP_START_SERVICE_DISCOVERY, hdev))
> return;
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, mgmt_status(err),
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_status(err),
> cmd->param, 1);
> mgmt_pending_remove(cmd);
>
> @@ -6013,7 +6006,7 @@ static void stop_discovery_complete(struct hci_dev *hdev, void *data, int err)
>
> bt_dev_dbg(hdev, "err %d", err);
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, mgmt_status(err),
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_status(err),
> cmd->param, 1);
> mgmt_pending_remove(cmd);
>
> @@ -6238,7 +6231,7 @@ static void set_advertising_complete(struct hci_dev *hdev, void *data, int err)
> u8 status = mgmt_status(err);
>
> if (status) {
> - mgmt_pending_foreach(MGMT_OP_SET_ADVERTISING, hdev,
> + mgmt_pending_foreach(MGMT_OP_SET_ADVERTISING, hdev, true,
> cmd_status_rsp, &status);
> return;
> }
> @@ -6248,7 +6241,7 @@ static void set_advertising_complete(struct hci_dev *hdev, void *data, int err)
> else
> hci_dev_clear_flag(hdev, HCI_ADVERTISING);
>
> - mgmt_pending_foreach(MGMT_OP_SET_ADVERTISING, hdev, settings_rsp,
> + mgmt_pending_foreach(MGMT_OP_SET_ADVERTISING, hdev, true, settings_rsp,
> &match);
>
> new_settings(hdev, match.sk);
> @@ -6592,7 +6585,7 @@ static void set_bredr_complete(struct hci_dev *hdev, void *data, int err)
> */
> hci_dev_clear_flag(hdev, HCI_BREDR_ENABLED);
>
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode, mgmt_err);
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_err);
> } else {
> send_settings_rsp(cmd->sk, MGMT_OP_SET_BREDR, hdev);
> new_settings(hdev, cmd->sk);
> @@ -6729,7 +6722,7 @@ static void set_secure_conn_complete(struct hci_dev *hdev, void *data, int err)
> if (err) {
> u8 mgmt_err = mgmt_status(err);
>
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode, mgmt_err);
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode, mgmt_err);
> goto done;
> }
>
> @@ -7176,7 +7169,7 @@ static void get_conn_info_complete(struct hci_dev *hdev, void *data, int err)
> rp.max_tx_power = HCI_TX_POWER_INVALID;
> }
>
> - mgmt_cmd_complete(cmd->sk, cmd->index, MGMT_OP_GET_CONN_INFO, status,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, MGMT_OP_GET_CONN_INFO, status,
> &rp, sizeof(rp));
>
> mgmt_pending_free(cmd);
> @@ -7336,7 +7329,7 @@ static void get_clock_info_complete(struct hci_dev *hdev, void *data, int err)
> }
>
> complete:
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode, status, &rp,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode, status, &rp,
> sizeof(rp));
>
> mgmt_pending_free(cmd);
> @@ -8586,10 +8579,10 @@ static void add_advertising_complete(struct hci_dev *hdev, void *data, int err)
> rp.instance = cp->instance;
>
> if (err)
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err));
> else
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err), &rp, sizeof(rp));
>
> add_adv_complete(hdev, cmd->sk, cp->instance, err);
> @@ -8777,10 +8770,10 @@ static void add_ext_adv_params_complete(struct hci_dev *hdev, void *data,
>
> hci_remove_adv_instance(hdev, cp->instance);
>
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err));
> } else {
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err), &rp, sizeof(rp));
> }
>
> @@ -8927,10 +8920,10 @@ static void add_ext_adv_data_complete(struct hci_dev *hdev, void *data, int err)
> rp.instance = cp->instance;
>
> if (err)
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err));
> else
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err), &rp, sizeof(rp));
>
> mgmt_pending_free(cmd);
> @@ -9089,10 +9082,10 @@ static void remove_advertising_complete(struct hci_dev *hdev, void *data,
> rp.instance = cp->instance;
>
> if (err)
> - mgmt_cmd_status(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_status(cmd->sk, cmd->hdev->id, cmd->opcode,
> mgmt_status(err));
> else
> - mgmt_cmd_complete(cmd->sk, cmd->index, cmd->opcode,
> + mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
> MGMT_STATUS_SUCCESS, &rp, sizeof(rp));
>
> mgmt_pending_free(cmd);
> @@ -9364,7 +9357,7 @@ void mgmt_index_removed(struct hci_dev *hdev)
> if (test_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks))
> return;
>
> - mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &match);
> + mgmt_pending_foreach(0, hdev, true, cmd_complete_rsp, &match);
>
> if (hci_dev_test_flag(hdev, HCI_UNCONFIGURED)) {
> mgmt_index_event(MGMT_EV_UNCONF_INDEX_REMOVED, hdev, NULL, 0,
> @@ -9402,7 +9395,8 @@ void mgmt_power_on(struct hci_dev *hdev, int err)
> hci_update_passive_scan(hdev);
> }
>
> - mgmt_pending_foreach(MGMT_OP_SET_POWERED, hdev, settings_rsp, &match);
> + mgmt_pending_foreach(MGMT_OP_SET_POWERED, hdev, true, settings_rsp,
> + &match);
>
> new_settings(hdev, match.sk);
>
> @@ -9417,7 +9411,8 @@ void __mgmt_power_off(struct hci_dev *hdev)
> struct cmd_lookup match = { NULL, hdev };
> u8 zero_cod[] = { 0, 0, 0 };
>
> - mgmt_pending_foreach(MGMT_OP_SET_POWERED, hdev, settings_rsp, &match);
> + mgmt_pending_foreach(MGMT_OP_SET_POWERED, hdev, true, settings_rsp,
> + &match);
>
> /* If the power off is because of hdev unregistration let
> * use the appropriate INVALID_INDEX status. Otherwise use
> @@ -9431,7 +9426,7 @@ void __mgmt_power_off(struct hci_dev *hdev)
> else
> match.mgmt_status = MGMT_STATUS_NOT_POWERED;
>
> - mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &match);
> + mgmt_pending_foreach(0, hdev, true, cmd_complete_rsp, &match);
>
> if (memcmp(hdev->dev_class, zero_cod, sizeof(zero_cod)) != 0) {
> mgmt_limited_event(MGMT_EV_CLASS_OF_DEV_CHANGED, hdev,
> @@ -9672,7 +9667,6 @@ static void unpair_device_rsp(struct mgmt_pending_cmd *cmd, void *data)
> device_unpaired(hdev, &cp->addr.bdaddr, cp->addr.type, cmd->sk);
>
> cmd->cmd_complete(cmd, 0);
> - mgmt_pending_remove(cmd);
> }
>
> bool mgmt_powering_down(struct hci_dev *hdev)
> @@ -9728,8 +9722,8 @@ void mgmt_disconnect_failed(struct hci_dev *hdev, bdaddr_t *bdaddr,
> struct mgmt_cp_disconnect *cp;
> struct mgmt_pending_cmd *cmd;
>
> - mgmt_pending_foreach(MGMT_OP_UNPAIR_DEVICE, hdev, unpair_device_rsp,
> - hdev);
> + mgmt_pending_foreach(MGMT_OP_UNPAIR_DEVICE, hdev, true,
> + unpair_device_rsp, hdev);
>
> cmd = pending_find(MGMT_OP_DISCONNECT, hdev);
> if (!cmd)
> @@ -9922,7 +9916,7 @@ void mgmt_auth_enable_complete(struct hci_dev *hdev, u8 status)
>
> if (status) {
> u8 mgmt_err = mgmt_status(status);
> - mgmt_pending_foreach(MGMT_OP_SET_LINK_SECURITY, hdev,
> + mgmt_pending_foreach(MGMT_OP_SET_LINK_SECURITY, hdev, true,
> cmd_status_rsp, &mgmt_err);
> return;
> }
> @@ -9932,8 +9926,8 @@ void mgmt_auth_enable_complete(struct hci_dev *hdev, u8 status)
> else
> changed = hci_dev_test_and_clear_flag(hdev, HCI_LINK_SECURITY);
>
> - mgmt_pending_foreach(MGMT_OP_SET_LINK_SECURITY, hdev, settings_rsp,
> - &match);
> + mgmt_pending_foreach(MGMT_OP_SET_LINK_SECURITY, hdev, true,
> + settings_rsp, &match);
>
> if (changed)
> new_settings(hdev, match.sk);
> @@ -9957,9 +9951,12 @@ void mgmt_set_class_of_dev_complete(struct hci_dev *hdev, u8 *dev_class,
> {
> struct cmd_lookup match = { NULL, hdev, mgmt_status(status) };
>
> - mgmt_pending_foreach(MGMT_OP_SET_DEV_CLASS, hdev, sk_lookup, &match);
> - mgmt_pending_foreach(MGMT_OP_ADD_UUID, hdev, sk_lookup, &match);
> - mgmt_pending_foreach(MGMT_OP_REMOVE_UUID, hdev, sk_lookup, &match);
> + mgmt_pending_foreach(MGMT_OP_SET_DEV_CLASS, hdev, false, sk_lookup,
> + &match);
> + mgmt_pending_foreach(MGMT_OP_ADD_UUID, hdev, false, sk_lookup,
> + &match);
> + mgmt_pending_foreach(MGMT_OP_REMOVE_UUID, hdev, false, sk_lookup,
> + &match);
>
> if (!status) {
> mgmt_limited_event(MGMT_EV_CLASS_OF_DEV_CHANGED, hdev, dev_class,
> diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
> index 3713ff490c65..a88a07da3947 100644
> --- a/net/bluetooth/mgmt_util.c
> +++ b/net/bluetooth/mgmt_util.c
> @@ -217,30 +217,47 @@ int mgmt_cmd_complete(struct sock *sk, u16 index, u16 cmd, u8 status,
> struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> struct hci_dev *hdev)
> {
> - struct mgmt_pending_cmd *cmd;
> + struct mgmt_pending_cmd *cmd, *tmp;
>
> - list_for_each_entry(cmd, &hdev->mgmt_pending, list) {
> + mutex_lock(&hdev->mgmt_pending_lock);
> +
> + list_for_each_entry_safe(cmd, tmp, &hdev->mgmt_pending, list) {
> if (hci_sock_get_channel(cmd->sk) != channel)
> continue;
> - if (cmd->opcode == opcode)
> +
> + if (cmd->opcode == opcode) {
> + mutex_unlock(&hdev->mgmt_pending_lock);
> return cmd;
Nothing appears to prevent cmd from being freed immediately after
mutex_unlock()
Then, the same UAF as in the stacktrace in the commit message would
still be possible.
Maybe instead:
lockdep_assert_held(&hdev->mgmt_pending_lock);
here and have the caller hold the lock as long as it uses the cmd?
Looks like callers are not doing something that takes a long time, so
it could work.
> + }
> }
>
> + mutex_unlock(&hdev->mgmt_pending_lock);
> +
> return NULL;
> }
>
> -void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> +void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev, bool remove,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data)
> {
> struct mgmt_pending_cmd *cmd, *tmp;
>
> + mutex_lock(&hdev->mgmt_pending_lock);
> +
> list_for_each_entry_safe(cmd, tmp, &hdev->mgmt_pending, list) {
> if (opcode > 0 && cmd->opcode != opcode)
> continue;
>
> + if (remove)
> + list_del(&cmd->list);
> +
> cb(cmd, data);
> +
> + if (remove)
> + mgmt_pending_free(cmd);
> }
> +
> + mutex_unlock(&hdev->mgmt_pending_lock);
> }
>
> struct mgmt_pending_cmd *mgmt_pending_new(struct sock *sk, u16 opcode,
> @@ -254,7 +271,7 @@ struct mgmt_pending_cmd *mgmt_pending_new(struct sock *sk, u16 opcode,
> return NULL;
>
> cmd->opcode = opcode;
> - cmd->index = hdev->id;
> + cmd->hdev = hdev;
>
> cmd->param = kmemdup(data, len, GFP_KERNEL);
> if (!cmd->param) {
> @@ -280,7 +297,9 @@ struct mgmt_pending_cmd *mgmt_pending_add(struct sock *sk, u16 opcode,
> if (!cmd)
> return NULL;
>
> + mutex_lock(&hdev->mgmt_pending_lock);
> list_add_tail(&cmd->list, &hdev->mgmt_pending);
> + mutex_unlock(&hdev->mgmt_pending_lock);
>
> return cmd;
> }
> @@ -294,7 +313,10 @@ void mgmt_pending_free(struct mgmt_pending_cmd *cmd)
>
> void mgmt_pending_remove(struct mgmt_pending_cmd *cmd)
> {
> + mutex_lock(&cmd->hdev->mgmt_pending_lock);
I think this deadlocks in mgmt_index_removed() -> mgmt_pending_foreach
-> cmd_complete_rsp -> mgmt_pending_remove
Maybe again lockdep_assert_held(&cmd->hdev->mgmt_pending_lock); and
have caller to hold lock.
> list_del(&cmd->list);
> + mutex_unlock(&cmd->hdev->mgmt_pending_lock);
> +
> mgmt_pending_free(cmd);
> }
>
> diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
> index f2ba994ab1d8..024e51dd6937 100644
> --- a/net/bluetooth/mgmt_util.h
> +++ b/net/bluetooth/mgmt_util.h
> @@ -33,7 +33,7 @@ struct mgmt_mesh_tx {
> struct mgmt_pending_cmd {
> struct list_head list;
> u16 opcode;
> - int index;
> + struct hci_dev *hdev;
> void *param;
> size_t param_len;
> struct sock *sk;
> @@ -54,7 +54,7 @@ int mgmt_cmd_complete(struct sock *sk, u16 index, u16 cmd, u8 status,
>
> struct mgmt_pending_cmd *mgmt_pending_find(unsigned short channel, u16 opcode,
> struct hci_dev *hdev);
> -void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev,
> +void mgmt_pending_foreach(u16 opcode, struct hci_dev *hdev, bool remove,
> void (*cb)(struct mgmt_pending_cmd *cmd, void *data),
> void *data);
> struct mgmt_pending_cmd *mgmt_pending_add(struct sock *sk, u16 opcode,
--
Pauli Virtanen
