Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1

If hdev->le_num_of_adv_sets is set to 1 it means that only handle 0x00
can be used, but since the MGMT interface instances start from

Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1

If hdev->le_num_of_adv_sets is set to 1 it means that only handle 0x00
can be used, but since the MGMT interface instances start from 1
(instance 0 means all instances in case of MGMT_OP_REMOVE_ADVERTISING)
the code needs to map the instance to handle otherwise users will not be
able to advertise as instance 1 would attempt to use handle 0x01.

Fixes: 1d0fac2c38ed ("Bluetooth: Use controller sets when available")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: HCI: Remove HCI_AMP support

Since BT_HS has been remove HCI_AMP controllers no longer has any use so
remove it along with the capability of creating AMP controllers.

Since we no longer n

Bluetooth: HCI: Remove HCI_AMP support

Since BT_HS has been remove HCI_AMP controllers no longer has any use so
remove it along with the capability of creating AMP controllers.

Since we no longer need to differentiate between AMP and Primary
controllers, as only HCI_PRIMARY is left, this also remove
hdev->dev_type altogether.

Fixes: e7b02296fb40 ("Bluetooth: Remove BT_HS")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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LE Create Connection command timeout increased to 20 secs

On our DUT, we can see that the host issues create connection cancel
command after 4-sec if there is no connection complete event for
LE cre

LE Create Connection command timeout increased to 20 secs

On our DUT, we can see that the host issues create connection cancel
command after 4-sec if there is no connection complete event for
LE create connection cmd.
As per core spec v5.3 section 7.8.5, advertisement interval range is-

Advertising_Interval_Min
Default : 0x0800(1.28s)
Time Range: 20ms to 10.24s

Advertising_Interval_Max
Default : 0x0800(1.28s)
Time Range: 20ms to 10.24s

If the remote device is using adv interval of > 4 sec, it is
difficult to make a connection with the current timeout value.
Also, with the default interval of 1.28 sec, we will get only
3 chances to capture the adv packets with the 4 sec window.
Hence we want to increase this timeout to 20sec.

Signed-off-by: Mahesh Talewad <mahesh.talewad@nxp.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_event: Set DISCOVERY_FINDING on SCAN_ENABLED

This makes sure that discovery state is properly synchronized otherwise
reports may not generate MGMT DeviceFound events as it would be as

Bluetooth: hci_event: Set DISCOVERY_FINDING on SCAN_ENABLED

This makes sure that discovery state is properly synchronized otherwise
reports may not generate MGMT DeviceFound events as it would be assumed
that it was not initiated by a discovery session.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: Add proper definitions for scan interval and window

This adds proper definitions for scan interval and window and then make
use of them instead their values.

Signed-off-by: Luiz Augusto

Bluetooth: Add proper definitions for scan interval and window

This adds proper definitions for scan interval and window and then make
use of them instead their values.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: msft: fix slab-use-after-free in msft_do_close()

Tying the msft->data lifetime to hdev by freeing it in
hci_release_dev() to fix the following case:

[use]
msft_do_close()
msft = hdev->

Bluetooth: msft: fix slab-use-after-free in msft_do_close()

Tying the msft->data lifetime to hdev by freeing it in
hci_release_dev() to fix the following case:

[use]
msft_do_close()
msft = hdev->msft_data;
if (!msft) ...(1) <- passed.
return;
mutex_lock(&msft->filter_lock); ...(4) <- used after freed.

[free]
msft_unregister()
msft = hdev->msft_data;
hdev->msft_data = NULL; ...(2)
kfree(msft); ...(3) <- msft is freed.

==================================================================
BUG: KASAN: slab-use-after-free in __mutex_lock_common
kernel/locking/mutex.c:587 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30
kernel/locking/mutex.c:752
Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309

Fixes: bf6a4e30ffbd ("Bluetooth: disable advertisement filters during suspend")
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_sync: Fix not checking error on hci_cmd_sync_cancel_sync

hci_cmd_sync_cancel_sync shall check the error passed to it since it
will be propagated using req_result which is __u32 it nee

Bluetooth: hci_sync: Fix not checking error on hci_cmd_sync_cancel_sync

hci_cmd_sync_cancel_sync shall check the error passed to it since it
will be propagated using req_result which is __u32 it needs to be
properly set to a positive value if it was passed as negative othertise
IS_ERR will not trigger as -(errno) would be converted to a positive
value.

Fixes: 63298d6e752f ("Bluetooth: hci_core: Cancel request on command timeout")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reported-and-tested-by: Thorsten Leemhuis <linux@leemhuis.info>
Closes: https://lore.kernel.org/all/08275279-7462-4f4a-a0ee-8aa015f829bc@leemhuis.info/

show more ...

Bluetooth: fix use-after-free in accessing skb after sending it

hci_send_cmd_sync first sends skb and then tries to clone it. However,
the driver may have already freed the skb at that point.

Fix

Bluetooth: fix use-after-free in accessing skb after sending it

hci_send_cmd_sync first sends skb and then tries to clone it. However,
the driver may have already freed the skb at that point.

Fix by cloning the sent_cmd cloned just above, instead of the original.

Log:
================================================================
BUG: KASAN: slab-use-after-free in __copy_skb_header+0x1a/0x240
...
Call Trace: ..
__skb_clone+0x59/0x2c0
hci_cmd_work+0x3b3/0x3d0 [bluetooth]
process_one_work+0x459/0x900
...
Allocated by task 129: ...
__alloc_skb+0x1ae/0x220
__hci_cmd_sync_sk+0x44c/0x7a0 [bluetooth]
__hci_cmd_sync_status+0x24/0xb0 [bluetooth]
set_cig_params_sync+0x778/0x7d0 [bluetooth]
...
Freed by task 0: ...
kmem_cache_free+0x157/0x3c0
__usb_hcd_giveback_urb+0x11e/0x1e0
usb_giveback_urb_bh+0x1ad/0x2a0
tasklet_action_common.isra.0+0x259/0x4a0
__do_softirq+0x15b/0x5a7
================================================================

Fixes: 2615fd9a7c25 ("Bluetooth: hci_sync: Fix overwriting request callback")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_core: Fix possible buffer overflow

struct hci_dev_info has a fixed size name[8] field so in the event that
hdev->name is bigger than that strcpy would attempt to write past its
size,

Bluetooth: hci_core: Fix possible buffer overflow

struct hci_dev_info has a fixed size name[8] field so in the event that
hdev->name is bigger than that strcpy would attempt to write past its
size, so this fixes this problem by switching to use strscpy.

Fixes: dcda165706b9 ("Bluetooth: hci_core: Fix build warnings")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_sync: Fix overwriting request callback

In a few cases the stack may generate commands as responses to events
which would happen to overwrite the sent_cmd, so this attempts to store
th

Bluetooth: hci_sync: Fix overwriting request callback

In a few cases the stack may generate commands as responses to events
which would happen to overwrite the sent_cmd, so this attempts to store
the request in req_skb so even if sent_cmd is replaced with a new
command the pending request will remain in stored in req_skb.

Fixes: 6a98e3836fa2 ("Bluetooth: Add helper for serialized HCI command execution")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: Remove usage of the deprecated ida_simple_xx() API

ida_alloc() and ida_free() should be preferred to the deprecated
ida_simple_get() and ida_simple_remove().

Note that the upper limit of

Bluetooth: Remove usage of the deprecated ida_simple_xx() API

ida_alloc() and ida_free() should be preferred to the deprecated
ida_simple_get() and ida_simple_remove().

Note that the upper limit of ida_simple_get() is exclusive, but the one of
ida_alloc_max() is inclusive. So a -1 has been added when needed.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_core: Cancel request on command timeout

If command has timed out call __hci_cmd_sync_cancel to notify the
hci_req since it will inevitably cause a timeout.

This also rework the code

Bluetooth: hci_core: Cancel request on command timeout

If command has timed out call __hci_cmd_sync_cancel to notify the
hci_req since it will inevitably cause a timeout.

This also rework the code around __hci_cmd_sync_cancel since it was
wrongly assuming it needs to cancel timer as well, but sometimes the
timers have not been started or in fact they already had timed out in
which case they don't need to be cancel yet again.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: Disconnect connected devices before rfkilling adapter

On a lot of platforms (at least the MS Surface devices, M1 macbooks, and
a few ThinkPads) firmware doesn't do its job when rfkilling

Bluetooth: Disconnect connected devices before rfkilling adapter

On a lot of platforms (at least the MS Surface devices, M1 macbooks, and
a few ThinkPads) firmware doesn't do its job when rfkilling a device
and the bluetooth adapter is not actually shut down properly on rfkill.
This leads to connected devices remaining in connected state and the
bluetooth connection eventually timing out after rfkilling an adapter.

Use the rfkill hook in the HCI driver to go through the full power-off
sequence (including stopping scans and disconnecting devices) before
rfkilling it, just like MGMT_OP_SET_POWERED would do.

In case anything during the larger power-off sequence fails, make sure
the device is still closed and the rfkill ends up being effective in
the end.

Signed-off-by: Jonas Dreßler <verdre@v0yd.nl>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: Avoid potential use-after-free in hci_error_reset

While handling the HCI_EV_HARDWARE_ERROR event, if the underlying
BT controller is not responding, the GPIO reset mechanism would
free th

Bluetooth: Avoid potential use-after-free in hci_error_reset

While handling the HCI_EV_HARDWARE_ERROR event, if the underlying
BT controller is not responding, the GPIO reset mechanism would
free the hci_dev and lead to a use-after-free in hci_error_reset.

Here's the call trace observed on a ChromeOS device with Intel AX201:
queue_work_on+0x3e/0x6c
__hci_cmd_sync_sk+0x2ee/0x4c0 [bluetooth <HASH:3b4a6>]
? init_wait_entry+0x31/0x31
__hci_cmd_sync+0x16/0x20 [bluetooth <HASH:3b4a 6>]
hci_error_reset+0x4f/0xa4 [bluetooth <HASH:3b4a 6>]
process_one_work+0x1d8/0x33f
worker_thread+0x21b/0x373
kthread+0x13a/0x152
? pr_cont_work+0x54/0x54
? kthread_blkcg+0x31/0x31
ret_from_fork+0x1f/0x30

This patch holds the reference count on the hci_dev while processing
a HCI_EV_HARDWARE_ERROR event to avoid potential crash.

Fixes: c7741d16a57c ("Bluetooth: Perform a power cycle when receiving hardware error event")
Signed-off-by: Ying Hsu <yinghsu@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: Make handle of hci_conn be unique

The handle of new hci_conn is always HCI_CONN_HANDLE_MAX + 1 if
the handle of the first hci_conn entry in hci_dev->conn_hash->list
is not HCI_CONN_HANDLE

Bluetooth: Make handle of hci_conn be unique

The handle of new hci_conn is always HCI_CONN_HANDLE_MAX + 1 if
the handle of the first hci_conn entry in hci_dev->conn_hash->list
is not HCI_CONN_HANDLE_MAX + 1. Use ida to manage the allocation of
hci_conn->handle to make it be unique.

Fixes: 9f78191cc9f1 ("Bluetooth: hci_conn: Always allocate unique handles")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: hci_codec: Fix leaking content of local_codecs

The following memory leak can be observed when the controller supports
codecs which are stored in local_codecs list but the elements are nev

Bluetooth: hci_codec: Fix leaking content of local_codecs

The following memory leak can be observed when the controller supports
codecs which are stored in local_codecs list but the elements are never
freed:

unreferenced object 0xffff88800221d840 (size 32):
comm "kworker/u3:0", pid 36, jiffies 4294898739 (age 127.060s)
hex dump (first 32 bytes):
f8 d3 02 03 80 88 ff ff 80 d8 21 02 80 88 ff ff ..........!.....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffffb324f557>] __kmalloc+0x47/0x120
[<ffffffffb39ef37d>] hci_codec_list_add.isra.0+0x2d/0x160
[<ffffffffb39ef643>] hci_read_codec_capabilities+0x183/0x270
[<ffffffffb39ef9ab>] hci_read_supported_codecs+0x1bb/0x2d0
[<ffffffffb39f162e>] hci_read_local_codecs_sync+0x3e/0x60
[<ffffffffb39ff1b3>] hci_dev_open_sync+0x943/0x11e0
[<ffffffffb396d55d>] hci_power_on+0x10d/0x3f0
[<ffffffffb30c99b4>] process_one_work+0x404/0x800
[<ffffffffb30ca134>] worker_thread+0x374/0x670
[<ffffffffb30d9108>] kthread+0x188/0x1c0
[<ffffffffb304db6b>] ret_from_fork+0x2b/0x50
[<ffffffffb300206a>] ret_from_fork_asm+0x1a/0x30

Cc: stable@vger.kernel.org
Fixes: 8961987f3f5f ("Bluetooth: Enumerate local supported codec and cache details")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: hci_core: Fix build warnings

This fixes the following warnings:

net/bluetooth/hci_core.c: In function ‘hci_register_dev’:
net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output

Bluetooth: hci_core: Fix build warnings

This fixes the following warnings:

net/bluetooth/hci_core.c: In function ‘hci_register_dev’:
net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output may
be truncated writing between 1 and 10 bytes into a region of size 5
[-Wformat-truncation=]
2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
| ^~
net/bluetooth/hci_core.c:2620:50: note: directive argument in the range
[0, 2147483647]
2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
| ^~~~~~~
net/bluetooth/hci_core.c:2620:9: note: ‘snprintf’ output between 5 and
14 bytes into a destination of size 8
2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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Bluetooth: Fix hci_link_tx_to RCU lock usage

Syzbot found a bug "BUG: sleeping function called from invalid context
at kernel/locking/mutex.c:580". It is because hci_link_tx_to holds an
RCU read loc

Bluetooth: Fix hci_link_tx_to RCU lock usage

Syzbot found a bug "BUG: sleeping function called from invalid context
at kernel/locking/mutex.c:580". It is because hci_link_tx_to holds an
RCU read lock and calls hci_disconnect which would hold a mutex lock
since the commit a13f316e90fd ("Bluetooth: hci_conn: Consolidate code
for aborting connections"). Here's an example call trace:

__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xfc/0x174 lib/dump_stack.c:106
___might_sleep+0x4a9/0x4d3 kernel/sched/core.c:9663
__mutex_lock_common kernel/locking/mutex.c:576 [inline]
__mutex_lock+0xc7/0x6e7 kernel/locking/mutex.c:732
hci_cmd_sync_queue+0x3a/0x287 net/bluetooth/hci_sync.c:388
hci_abort_conn+0x2cd/0x2e4 net/bluetooth/hci_conn.c:1812
hci_disconnect+0x207/0x237 net/bluetooth/hci_conn.c:244
hci_link_tx_to net/bluetooth/hci_core.c:3254 [inline]
__check_timeout net/bluetooth/hci_core.c:3419 [inline]
__check_timeout+0x310/0x361 net/bluetooth/hci_core.c:3399
hci_sched_le net/bluetooth/hci_core.c:3602 [inline]
hci_tx_work+0xe8f/0x12d0 net/bluetooth/hci_core.c:3652
process_one_work+0x75c/0xba1 kernel/workqueue.c:2310
worker_thread+0x5b2/0x73a kernel/workqueue.c:2457
kthread+0x2f7/0x30b kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

This patch releases RCU read lock before calling hci_disconnect and
reacquires it afterward to fix the bug.

Fixes: a13f316e90fd ("Bluetooth: hci_conn: Consolidate code for aborting connections")
Signed-off-by: Ying Hsu <yinghsu@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()

KSAN reports use-after-free in hci_add_adv_monitor().

While adding an adv monitor,
hci_add_adv_monitor() calls ->

Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()

KSAN reports use-after-free in hci_add_adv_monitor().

While adding an adv monitor,
hci_add_adv_monitor() calls ->
msft_add_monitor_pattern() calls ->
msft_add_monitor_sync() calls ->
msft_le_monitor_advertisement_cb() calls in an error case ->
hci_free_adv_monitor() which frees the *moniter.

This is referenced by bt_dev_dbg() in hci_add_adv_monitor().

Fix the bt_dev_dbg() by using handle instead of monitor->handle.

Fixes: b747a83690c8 ("Bluetooth: hci_sync: Refactor add Adv Monitor")
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: Fix potential use-after-free when clear keys

Similar to commit c5d2b6fa26b5 ("Bluetooth: Fix use-after-free in
hci_remove_ltk/hci_remove_irk"). We can not access k after kfree_rcu()
call.

Bluetooth: Fix potential use-after-free when clear keys

Similar to commit c5d2b6fa26b5 ("Bluetooth: Fix use-after-free in
hci_remove_ltk/hci_remove_irk"). We can not access k after kfree_rcu()
call.

Fixes: d7d41682efc2 ("Bluetooth: Fix Suspicious RCU usage warnings")
Signed-off-by: Min Li <lm0963hack@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: af_bluetooth: Make BT_PKT_STATUS generic

This makes the handling of BT_PKT_STATUS more generic so it can be
reused by sockets other than SCO like BT_DEFER_SETUP, etc.

Signed-off-by: Luiz

Bluetooth: af_bluetooth: Make BT_PKT_STATUS generic

This makes the handling of BT_PKT_STATUS more generic so it can be
reused by sockets other than SCO like BT_DEFER_SETUP, etc.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: Fix hci_suspend_sync crash

If hci_unregister_dev() frees the hci_dev object but hci_suspend_notifier
may still be accessing it, it can cause the program to crash.
Here's the call trace:

Bluetooth: Fix hci_suspend_sync crash

If hci_unregister_dev() frees the hci_dev object but hci_suspend_notifier
may still be accessing it, it can cause the program to crash.
Here's the call trace:
<4>[102152.653246] Call Trace:
<4>[102152.653254] hci_suspend_sync+0x109/0x301 [bluetooth]
<4>[102152.653259] hci_suspend_dev+0x78/0xcd [bluetooth]
<4>[102152.653263] hci_suspend_notifier+0x42/0x7a [bluetooth]
<4>[102152.653268] notifier_call_chain+0x43/0x6b
<4>[102152.653271] __blocking_notifier_call_chain+0x48/0x69
<4>[102152.653273] __pm_notifier_call_chain+0x22/0x39
<4>[102152.653276] pm_suspend+0x287/0x57c
<4>[102152.653278] state_store+0xae/0xe5
<4>[102152.653281] kernfs_fop_write+0x109/0x173
<4>[102152.653284] __vfs_write+0x16f/0x1a2
<4>[102152.653287] ? selinux_file_permission+0xca/0x16f
<4>[102152.653289] ? security_file_permission+0x36/0x109
<4>[102152.653291] vfs_write+0x114/0x21d
<4>[102152.653293] __x64_sys_write+0x7b/0xdb
<4>[102152.653296] do_syscall_64+0x59/0x194
<4>[102152.653299] entry_SYSCALL_64_after_hwframe+0x5c/0xc1

This patch holds the reference count of the hci_dev object while
processing it in hci_suspend_notifier to avoid potential crash
caused by the race condition.

Signed-off-by: Ying Hsu <yinghsu@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: hci_sync: Don't double print name in add/remove adv_monitor

The hci_add_adv_monitor() hci_remove_adv_monitor() functions call
bt_dev_dbg() to print some debug statements. The bt_dev_dbg()

Bluetooth: hci_sync: Don't double print name in add/remove adv_monitor

The hci_add_adv_monitor() hci_remove_adv_monitor() functions call
bt_dev_dbg() to print some debug statements. The bt_dev_dbg() macro
automatically adds in the device's name. That means that we shouldn't
include the name in the bt_dev_dbg() calls.

Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_remove_adv_monitor()

KASAN reports that there's a use-after-free in
hci_remove_adv_monitor(). Trawling through the disassembly, you can
see t

Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_remove_adv_monitor()

KASAN reports that there's a use-after-free in
hci_remove_adv_monitor(). Trawling through the disassembly, you can
see that the complaint is from the access in bt_dev_dbg() under the
HCI_ADV_MONITOR_EXT_MSFT case. The problem case happens because
msft_remove_monitor() can end up freeing the monitor
structure. Specifically:
hci_remove_adv_monitor() ->
msft_remove_monitor() ->
msft_remove_monitor_sync() ->
msft_le_cancel_monitor_advertisement_cb() ->
hci_free_adv_monitor()

Let's fix the problem by just stashing the relevant data when it's
still valid.

Fixes: 7cf5c2978f23 ("Bluetooth: hci_sync: Refactor remove Adv Monitor")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

show more ...

Bluetooth: use RCU for hci_conn_params and iterate safely in hci_sync

hci_update_accept_list_sync iterates over hdev->pend_le_conns and
hdev->pend_le_reports, and waits for controller events in the

Bluetooth: use RCU for hci_conn_params and iterate safely in hci_sync

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 or any other item
in the list, 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 or hdev->lock for the whole loop,
copy list items first and then iterate on the copy. 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 e.g. by BlueZ new
mgmt-tester case "Add + Remove Device Nowait - Success", or by changing
hci_le_set_cig_params to always return false, and running iso-tester:

==================================================================
BUG: KASAN: slab-use-after-free in hci_update_passive_scan_sync (net/bluetooth/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:107)
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/bluetooth/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/bluetooth/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:720 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/common.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)
==================================================================

Fixes: e8907f76544f ("Bluetooth: hci_sync: Make use of hci_cmd_sync_queue set 3")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

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