This adds CONFIG_BT_LE_L2CAP_ECRED which can be used to enable L2CAP
Enhanced Credit Flow Control Mode by default, previously it was only
possible to set it via module parameter (e.g. bluetooth.enable_ecred=1).
Since L2CAP ECRED mode is required by the likes of EATT which is
recommended for LE Audio this enables it by default.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Tested-By: Tedd Ho-Jeong An <tedd.an@intel.com>
On l2cap_parse_conf_req the variable efs is only initialized if
remote_efs has been set.
CVE: CVE-2022-42895
CC: stable@vger.kernel.org
Reported-by: Tamás Koczka <poprdi@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com>
l2cap_global_chan_by_psm shall not return fixed channels as they are not
meant to be connected by (S)PSM.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com>
The Bluetooth spec states that the valid range for SPSM is from
0x0001-0x00ff so it is invalid to accept values outside of this range:
BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
page 1059:
Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
CVE: CVE-2022-42896
CC: stable@vger.kernel.org
Reported-by: Tamás Koczka <poprdi@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Syzkaller reports a memory leak as follows:
====================================
BUG: memory leak
unreferenced object 0xffff88810d81ac00 (size 240):
[...]
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff838733d9>] __alloc_skb+0x1f9/0x270 net/core/skbuff.c:418
[<ffffffff833f742f>] alloc_skb include/linux/skbuff.h:1257 [inline]
[<ffffffff833f742f>] bt_skb_alloc include/net/bluetooth/bluetooth.h:469 [inline]
[<ffffffff833f742f>] vhci_get_user drivers/bluetooth/hci_vhci.c:391 [inline]
[<ffffffff833f742f>] vhci_write+0x5f/0x230 drivers/bluetooth/hci_vhci.c:511
[<ffffffff815e398d>] call_write_iter include/linux/fs.h:2192 [inline]
[<ffffffff815e398d>] new_sync_write fs/read_write.c:491 [inline]
[<ffffffff815e398d>] vfs_write+0x42d/0x540 fs/read_write.c:578
[<ffffffff815e3cdd>] ksys_write+0x9d/0x160 fs/read_write.c:631
[<ffffffff845e0645>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845e0645>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
====================================
HCI core will uses hci_rx_work() to process frame, which is queued to
the hdev->rx_q tail in hci_recv_frame() by HCI driver.
Yet the problem is that, HCI core may not free the skb after handling
ACL data packets. To be more specific, when start fragment does not
contain the L2CAP length, HCI core just copies skb into conn->rx_skb and
finishes frame process in l2cap_recv_acldata(), without freeing the skb,
which triggers the above memory leak.
This patch solves it by releasing the relative skb, after processing
the above case in l2cap_recv_acldata().
Fixes: 4d7ea8ee90 ("Bluetooth: L2CAP: Fix handling fragmented length")
Link: https://lore.kernel.org/all/0000000000000d0b1905e6aaef64@google.com/
Reported-and-tested-by: syzbot+8f819e36e01022991cfa@syzkaller.appspotmail.com
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
When l2cap_recv_frame() is invoked to receive data, and the cid is
L2CAP_CID_A2MP, if the channel does not exist, it will create a channel.
However, after a channel is created, the hold operation of the channel
is not performed. In this case, the value of channel reference counting
is 1. As a result, after hci_error_reset() is triggered, l2cap_conn_del()
invokes the close hook function of A2MP to release the channel. Then
l2cap_chan_unlock(chan) will trigger UAF issue.
The process is as follows:
Receive data:
l2cap_data_channel()
a2mp_channel_create() --->channel ref is 2
l2cap_chan_put() --->channel ref is 1
Triger event:
hci_error_reset()
hci_dev_do_close()
...
l2cap_disconn_cfm()
l2cap_conn_del()
l2cap_chan_hold() --->channel ref is 2
l2cap_chan_del() --->channel ref is 1
a2mp_chan_close_cb() --->channel ref is 0, release channel
l2cap_chan_unlock() --->UAF of channel
The detailed Call Trace is as follows:
BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0xa6/0x5e0
Read of size 8 at addr ffff8880160664b8 by task kworker/u11:1/7593
Workqueue: hci0 hci_error_reset
Call Trace:
<TASK>
dump_stack_lvl+0xcd/0x134
print_report.cold+0x2ba/0x719
kasan_report+0xb1/0x1e0
kasan_check_range+0x140/0x190
__mutex_unlock_slowpath+0xa6/0x5e0
l2cap_conn_del+0x404/0x7b0
l2cap_disconn_cfm+0x8c/0xc0
hci_conn_hash_flush+0x11f/0x260
hci_dev_close_sync+0x5f5/0x11f0
hci_dev_do_close+0x2d/0x70
hci_error_reset+0x9e/0x140
process_one_work+0x98a/0x1620
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
</TASK>
Allocated by task 7593:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0xa9/0xd0
l2cap_chan_create+0x40/0x930
amp_mgr_create+0x96/0x990
a2mp_channel_create+0x7d/0x150
l2cap_recv_frame+0x51b8/0x9a70
l2cap_recv_acldata+0xaa3/0xc00
hci_rx_work+0x702/0x1220
process_one_work+0x98a/0x1620
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
Freed by task 7593:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_set_free_info+0x20/0x30
____kasan_slab_free+0x167/0x1c0
slab_free_freelist_hook+0x89/0x1c0
kfree+0xe2/0x580
l2cap_chan_put+0x22a/0x2d0
l2cap_conn_del+0x3fc/0x7b0
l2cap_disconn_cfm+0x8c/0xc0
hci_conn_hash_flush+0x11f/0x260
hci_dev_close_sync+0x5f5/0x11f0
hci_dev_do_close+0x2d/0x70
hci_error_reset+0x9e/0x140
process_one_work+0x98a/0x1620
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
Last potentially related work creation:
kasan_save_stack+0x1e/0x40
__kasan_record_aux_stack+0xbe/0xd0
call_rcu+0x99/0x740
netlink_release+0xe6a/0x1cf0
__sock_release+0xcd/0x280
sock_close+0x18/0x20
__fput+0x27c/0xa90
task_work_run+0xdd/0x1a0
exit_to_user_mode_prepare+0x23c/0x250
syscall_exit_to_user_mode+0x19/0x50
do_syscall_64+0x42/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Second to last potentially related work creation:
kasan_save_stack+0x1e/0x40
__kasan_record_aux_stack+0xbe/0xd0
call_rcu+0x99/0x740
netlink_release+0xe6a/0x1cf0
__sock_release+0xcd/0x280
sock_close+0x18/0x20
__fput+0x27c/0xa90
task_work_run+0xdd/0x1a0
exit_to_user_mode_prepare+0x23c/0x250
syscall_exit_to_user_mode+0x19/0x50
do_syscall_64+0x42/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: d0be8347c6 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Fix the race condition between the following two flows that run in
parallel:
1. l2cap_reassemble_sdu -> chan->ops->recv (l2cap_sock_recv_cb) ->
__sock_queue_rcv_skb.
2. bt_sock_recvmsg -> skb_recv_datagram, skb_free_datagram.
An SKB can be queued by the first flow and immediately dequeued and
freed by the second flow, therefore the callers of l2cap_reassemble_sdu
can't use the SKB after that function returns. However, some places
continue accessing struct l2cap_ctrl that resides in the SKB's CB for a
short time after l2cap_reassemble_sdu returns, leading to a
use-after-free condition (the stack trace is below, line numbers for
kernel 5.19.8).
Fix it by keeping a local copy of struct l2cap_ctrl.
BUG: KASAN: use-after-free in l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth
Read of size 1 at addr ffff88812025f2f0 by task kworker/u17:3/43169
Workqueue: hci0 hci_rx_work [bluetooth]
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
print_report.cold (mm/kasan/report.c:314 mm/kasan/report.c:429)
? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth
kasan_report (mm/kasan/report.c:162 mm/kasan/report.c:493)
? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth
l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth
l2cap_rx (net/bluetooth/l2cap_core.c:7236 net/bluetooth/l2cap_core.c:7271) bluetooth
ret_from_fork (arch/x86/entry/entry_64.S:306)
</TASK>
Allocated by task 43169:
kasan_save_stack (mm/kasan/common.c:39)
__kasan_slab_alloc (mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:469)
kmem_cache_alloc_node (mm/slab.h:750 mm/slub.c:3243 mm/slub.c:3293)
__alloc_skb (net/core/skbuff.c:414)
l2cap_recv_frag (./include/net/bluetooth/bluetooth.h:425 net/bluetooth/l2cap_core.c:8329) bluetooth
l2cap_recv_acldata (net/bluetooth/l2cap_core.c:8442) bluetooth
hci_rx_work (net/bluetooth/hci_core.c:3642 net/bluetooth/hci_core.c:3832) bluetooth
process_one_work (kernel/workqueue.c:2289)
worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2437)
kthread (kernel/kthread.c:376)
ret_from_fork (arch/x86/entry/entry_64.S:306)
Freed by task 27920:
kasan_save_stack (mm/kasan/common.c:39)
kasan_set_track (mm/kasan/common.c:45)
kasan_set_free_info (mm/kasan/generic.c:372)
____kasan_slab_free (mm/kasan/common.c:368 mm/kasan/common.c:328)
slab_free_freelist_hook (mm/slub.c:1780)
kmem_cache_free (mm/slub.c:3536 mm/slub.c:3553)
skb_free_datagram (./include/net/sock.h:1578 ./include/net/sock.h:1639 net/core/datagram.c:323)
bt_sock_recvmsg (net/bluetooth/af_bluetooth.c:295) bluetooth
l2cap_sock_recvmsg (net/bluetooth/l2cap_sock.c:1212) bluetooth
sock_read_iter (net/socket.c:1087)
new_sync_read (./include/linux/fs.h:2052 fs/read_write.c:401)
vfs_read (fs/read_write.c:482)
ksys_read (fs/read_write.c:620)
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)
Link: https://lore.kernel.org/linux-bluetooth/CAKErNvoqga1WcmoR3-0875esY6TVWFQDandbVZncSiuGPBQXLA@mail.gmail.com/T/#u
Fixes: d2a7ac5d5d ("Bluetooth: Add the ERTM receive state machine")
Fixes: 4b51dae967 ("Bluetooth: Add streaming mode receive and incoming packet classifier")
Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This uses l2cap_chan_hold_unless_zero() after calling
__l2cap_get_chan_blah() to prevent the following trace:
Bluetooth: l2cap_core.c:static void l2cap_chan_destroy(struct kref
*kref)
Bluetooth: chan 0000000023c4974d
Bluetooth: parent 00000000ae861c08
==================================================================
BUG: KASAN: use-after-free in __mutex_waiter_is_first
kernel/locking/mutex.c:191 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common
kernel/locking/mutex.c:671 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x278/0x400
kernel/locking/mutex.c:729
Read of size 8 at addr ffff888006a49b08 by task kworker/u3:2/389
Link: https://lore.kernel.org/lkml/20220622082716.478486-1-lee.jones@linaro.org
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
syzbot is reporting cancel_delayed_work() without INIT_DELAYED_WORK() at
l2cap_chan_del() [1], for CONF_NOT_COMPLETE flag (which meant to prevent
l2cap_chan_del() from calling cancel_delayed_work()) is cleared by timer
which fires before l2cap_chan_del() is called by closing file descriptor
created by socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_L2CAP).
l2cap_bredr_sig_cmd(L2CAP_CONF_REQ) and l2cap_bredr_sig_cmd(L2CAP_CONF_RSP)
are calling l2cap_ertm_init(chan), and they call l2cap_chan_ready() (which
clears CONF_NOT_COMPLETE flag) only when l2cap_ertm_init(chan) succeeded.
l2cap_sock_init() does not call l2cap_ertm_init(chan), and it instead sets
CONF_NOT_COMPLETE flag by calling l2cap_chan_set_defaults(). However, when
connect() is requested, "command 0x0409 tx timeout" happens after 2 seconds
from connect() request, and CONF_NOT_COMPLETE flag is cleared after 4
seconds from connect() request, for l2cap_conn_start() from
l2cap_info_timeout() callback scheduled by
schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
in l2cap_connect() is calling l2cap_chan_ready().
Fix this problem by initializing delayed works used by L2CAP_MODE_ERTM
mode as soon as l2cap_chan_create() allocates a channel, like I did in
commit be85972393 ("Bluetooth: initialize skb_queue_head at
l2cap_chan_create()").
Link: https://syzkaller.appspot.com/bug?extid=83672956c7aa6af698b3 [1]
Reported-by: syzbot <syzbot+83672956c7aa6af698b3@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This attempts to fix the follow errors:
In function 'memcmp',
inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9,
inlined from 'l2cap_global_chan_by_psm' at
net/bluetooth/l2cap_core.c:2003:15:
./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp'
specified bound 6 exceeds source size 0 [-Werror=stringop-overread]
44 | #define __underlying_memcmp __builtin_memcmp
| ^
./include/linux/fortify-string.h:420:16: note: in expansion of macro
'__underlying_memcmp'
420 | return __underlying_memcmp(p, q, size);
| ^~~~~~~~~~~~~~~~~~~
In function 'memcmp',
inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9,
inlined from 'l2cap_global_chan_by_psm' at
net/bluetooth/l2cap_core.c:2004:15:
./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp'
specified bound 6 exceeds source size 0 [-Werror=stringop-overread]
44 | #define __underlying_memcmp __builtin_memcmp
| ^
./include/linux/fortify-string.h:420:16: note: in expansion of macro
'__underlying_memcmp'
420 | return __underlying_memcmp(p, q, size);
| ^~~~~~~~~~~~~~~~~~~
Fixes: 332f1795ca ("Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regression")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The patch d0be8347c623: "Bluetooth: L2CAP: Fix use-after-free caused
by l2cap_chan_put" from Jul 21, 2022, leads to the following Smatch
static checker warning:
net/bluetooth/l2cap_core.c:1977 l2cap_global_chan_by_psm()
error: we previously assumed 'c' could be null (see line 1996)
Fixes: d0be8347c6 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This fixes the following trace which is caused by hci_rx_work starting up
*after* the final channel reference has been put() during sock_close() but
*before* the references to the channel have been destroyed, so instead
the code now rely on kref_get_unless_zero/l2cap_chan_hold_unless_zero to
prevent referencing a channel that is about to be destroyed.
refcount_t: increment on 0; use-after-free.
BUG: KASAN: use-after-free in refcount_dec_and_test+0x20/0xd0
Read of size 4 at addr ffffffc114f5bf18 by task kworker/u17:14/705
CPU: 4 PID: 705 Comm: kworker/u17:14 Tainted: G S W
4.14.234-00003-g1fb6d0bd49a4-dirty #28
Hardware name: Qualcomm Technologies, Inc. SM8150 V2 PM8150
Google Inc. MSM sm8150 Flame DVT (DT)
Workqueue: hci0 hci_rx_work
Call trace:
dump_backtrace+0x0/0x378
show_stack+0x20/0x2c
dump_stack+0x124/0x148
print_address_description+0x80/0x2e8
__kasan_report+0x168/0x188
kasan_report+0x10/0x18
__asan_load4+0x84/0x8c
refcount_dec_and_test+0x20/0xd0
l2cap_chan_put+0x48/0x12c
l2cap_recv_frame+0x4770/0x6550
l2cap_recv_acldata+0x44c/0x7a4
hci_acldata_packet+0x100/0x188
hci_rx_work+0x178/0x23c
process_one_work+0x35c/0x95c
worker_thread+0x4cc/0x960
kthread+0x1a8/0x1c4
ret_from_fork+0x10/0x18
Cc: stable@kernel.org
Reported-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Similar to the handling of l2cap_ecred_connect in commit d3715b2333
("Bluetooth: use memset avoid memory leaks"), we thought a patch
might be needed here as well.
Use memset to initialize structs to prevent memory leaks
in l2cap_le_connect
Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
data.pid is set twice with the same value. Remove one of these redundant
calls.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use memset to initialize structs to prevent memory leaks
in l2cap_ecred_connect
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds hci_le_create_conn_sync and make hci_le_connect use it instead
of queueing multiple commands which may conflict with the likes of
hci_update_passive_scan which uses hci_cmd_sync_queue.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When connecting to a device using an RPA if the address has been
resolved by the controller (types 0x02 and 0x03) the identity address
shall be used as the actual RPA in the advertisement won't be visible
to the host.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch replaces some non-inclusive terms based on the appropriate
language mapping table compiled by the Bluetooth SIG:
https://specificationrefs.bluetooth.com/language-mapping/Appropriate_Language_Mapping_Table.pdf
Specifically, these terms are replaced:
blacklist -> reject list
whitelist -> accept list
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch replaces some non-inclusive terms based on the appropriate
language mapping table compiled by the Bluetooth SIG:
https://specificationrefs.bluetooth.com/language-mapping/Appropriate_Language_Mapping_Table.pdf
Specifically, these terms are replaced:
master -> initiator (for smp) or central (everything else)
slave -> responder (for smp) or peripheral (everything else)
The #define preprocessor terms are unchanged for now to not disturb
dependent APIs.
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The use of l2cap_chan_del is not safe under a loop using
list_for_each_entry.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The use of l2cap_chan_del is not safe under a loop using
list_for_each_entry.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When an MGMT_EV_DEVICE_CONNECTED event is reported back to the user
space we will set the flags to tell if the established connection is
outbound or not. This is useful for the user space to log better metrics
and error messages.
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Yu Liu <yudiliu@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use the correct print format. Printing an unsigned int value should use %u
instead of %d. For details, please read document:
Documentation/core-api/printk-formats.rst
Signed-off-by: Kai Ye <yekai13@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
1. Add space when needed;
2. Block comments style fix;
3. Move open brace '{' following function definitions to the next line;
4. Remove unnecessary braces '{}' for single statement blocks.
Signed-off-by: Meng Yu <yumeng18@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
void function return statements are not generally useful.
Signed-off-by: Meng Yu <yumeng18@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
syzbot is hitting "INFO: trying to register non-static key." message [1],
for "struct l2cap_chan"->tx_q.lock spinlock is not yet initialized when
l2cap_chan_del() is called due to e.g. timeout.
Since "struct l2cap_chan"->lock mutex is initialized at l2cap_chan_create()
immediately after "struct l2cap_chan" is allocated using kzalloc(), let's
as well initialize "struct l2cap_chan"->{tx_q,srej_q}.lock spinlocks there.
[1] https://syzkaller.appspot.com/bug?extid=fadfba6a911f6bf71842
Reported-and-tested-by: syzbot <syzbot+fadfba6a911f6bf71842@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Currently l2cap_chan_set_defaults() reset chan->conf_state to zero.
However, there is a flag CONF_NOT_COMPLETE which is set when
creating the l2cap_chan. It is suggested that the flag should be
cleared when l2cap_chan is ready, but when l2cap_chan_set_defaults()
is called, l2cap_chan is not yet ready. Therefore, we must set this
flag as the default.
Example crash call trace:
__dump_stack lib/dump_stack.c:15 [inline]
dump_stack+0xc4/0x118 lib/dump_stack.c:56
panic+0x1c6/0x38b kernel/panic.c:117
__warn+0x170/0x1b9 kernel/panic.c:471
warn_slowpath_fmt+0xc7/0xf8 kernel/panic.c:494
debug_print_object+0x175/0x193 lib/debugobjects.c:260
debug_object_assert_init+0x171/0x1bf lib/debugobjects.c:614
debug_timer_assert_init kernel/time/timer.c:629 [inline]
debug_assert_init kernel/time/timer.c:677 [inline]
del_timer+0x7c/0x179 kernel/time/timer.c:1034
try_to_grab_pending+0x81/0x2e5 kernel/workqueue.c:1230
cancel_delayed_work+0x7c/0x1c4 kernel/workqueue.c:2929
l2cap_clear_timer+0x1e/0x41 include/net/bluetooth/l2cap.h:834
l2cap_chan_del+0x2d8/0x37e net/bluetooth/l2cap_core.c:640
l2cap_chan_close+0x532/0x5d8 net/bluetooth/l2cap_core.c:756
l2cap_sock_shutdown+0x806/0x969 net/bluetooth/l2cap_sock.c:1174
l2cap_sock_release+0x64/0x14d net/bluetooth/l2cap_sock.c:1217
__sock_release+0xda/0x217 net/socket.c:580
sock_close+0x1b/0x1f net/socket.c:1039
__fput+0x322/0x55c fs/file_table.c:208
____fput+0x17/0x19 fs/file_table.c:244
task_work_run+0x19b/0x1d3 kernel/task_work.c:115
exit_task_work include/linux/task_work.h:21 [inline]
do_exit+0xe4c/0x204a kernel/exit.c:766
do_group_exit+0x291/0x291 kernel/exit.c:891
get_signal+0x749/0x1093 kernel/signal.c:2396
do_signal+0xa5/0xcdb arch/x86/kernel/signal.c:737
exit_to_usermode_loop arch/x86/entry/common.c:243 [inline]
prepare_exit_to_usermode+0xed/0x235 arch/x86/entry/common.c:277
syscall_return_slowpath+0x3a7/0x3b3 arch/x86/entry/common.c:348
int_ret_from_sys_call+0x25/0xa3
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reported-by: syzbot+338f014a98367a08a114@syzkaller.appspotmail.com
Reviewed-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving L2CAP_CREDIT_BASED_CONNECTION_REQ the remote may request
more channels than allowed by the spec (10 octecs = 5 CIDs) so this
checks if the number of channels is bigger than the maximum allowed and
respond with an error.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Bluetooth Core Specification v5.2, Vol. 3, Part A, section 1.4, table
1.1:
'Start Fragments always either begin with the first octet of the Basic
L2CAP header of a PDU or they have a length of zero (see [Vol 2] Part
B, Section 6.6.2).'
Apparently this was changed by the following errata:
https://www.bluetooth.org/tse/errata_view.cfm?errata_id=10216
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This test case is meant to verify that multiple
unknown options is included in the response.
BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part A
page 1057
'On an unknown option failure (Result=0x0003),
the option(s) that contain anoption type field that is not
understood by the recipient of the L2CAP_CONFIGURATION_REQ
packet shall be included in the L2CAP_CONFIGURATION_RSP
packet unless they are hints.'
Before this patch:
> ACL Data RX: Handle 11 flags 0x02 dlen 24
L2CAP: Configure Request (0x04) ident 18 len 16
Destination CID: 64
Flags: 0x0000
Option: Unknown (0x10) [mandatory]
10 00 11 02 11 00 12 02 12 00
< ACL Data TX: Handle 11 flags 0x00 dlen 17
L2CAP: Configure Response (0x05) ident 18 len 9
Source CID: 64
Flags: 0x0000
Result: Failure - unknown options (0x0003)
Option: Unknown (0x10) [mandatory]
12
After this patch:
> ACL Data RX: Handle 11 flags 0x02 dlen 24
L2CAP: Configure Request (0x04) ident 5 len 16
Destination CID: 64
Flags: 0x0000
Option: Unknown (0x10) [mandatory]
10 00 11 02 11 00 12 02 12 00
< ACL Data TX: Handle 11 flags 0x00 dlen 23
L2CAP: Configure Response (0x05) ident 5 len 15
Source CID: 64
Flags: 0x0000
Result: Failure - unknown options (0x0003)
Option: Unknown (0x10) [mandatory]
10 11 01 11 12 01 12
Signed-off-by: Jimmy Wahlberg <jimmywa@spotify.com>
Reviewed-by: Luiz Augusto Von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
According to the spec Ver 5.2, Vol 3, Part C, Sec 5.2.2.8:
Device in security mode 4 level 4 shall enforce:
128-bit equivalent strength for link and encryption keys required
using FIPS approved algorithms (E0 not allowed, SAFER+ not allowed,
and P-192 not allowed; encryption key not shortened)
This patch rejects connection with key size below 16 for FIPS
level services.
Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Only sockets will have the chan->data set to an actual sk, channels
like A2MP would have its own data which would likely cause a crash when
calling sk_filter, in order to fix this a new callback has been
introduced so channels can implement their own filtering if necessary.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If user decides to cancel the ongoing pairing process (e.g. by clicking
the cancel button on pairing/passkey window), abort any ongoing pairing
and then terminate the link if it was created because of the pair
device action.
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Fix 2 typos in L2CAP_CREDIT_BASED_CONNECTION_REQ (0x17) handling function, that
cause BlueZ answer with L2CAP_CR_LE_INVALID_PARAMS or L2CAP_CR_LE_INVALID_SCID
error on a correct ECRED connection request.
Enchanced Credit Based Mode support was recently introduced with the commit
15f02b9105 ("Bluetooth: L2CAP: Add initial code
for Enhanced Credit Based Mode").
Signed-off-by: Konstantin Forostyan <konstantin.forostyan@peiker-cee.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This uses the DEFER_SETUP flag to group channels with
L2CAP_CREDIT_BASED_CONNECTION_REQ.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
net/bluetooth/l2cap_core.c: In function l2cap_ecred_conn_req:
net/bluetooth/l2cap_core.c:5848:6: warning: variable credits set but not used [-Wunused-but-set-variable]
commit 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
involved this unused variable, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This should make it safe to have the code upstream without affecting
stable systems since there are a few details not sort out with ECRED
mode e.g: how to initiate multiple connections at once.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds the initial code for Enhanced Credit Based Mode which
introduces a new socket mode called L2CAP_MODE_EXT_FLOWCTL, which for
the most part work the same as L2CAP_MODE_LE_FLOWCTL but uses different
PDUs to setup the connections and also works over BR/EDR.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This uses skb_pull when parsing signalling PDUs so skb->data for
pointing to the current PDU and skb->len as the remaining bytes to be
processed.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There is no lock preventing both l2cap_sock_release() and
chan->ops->close() from running at the same time.
If we consider Thread A running l2cap_chan_timeout() and Thread B running
l2cap_sock_release(), expected behavior is:
A::l2cap_chan_timeout()->l2cap_chan_close()->l2cap_sock_teardown_cb()
A::l2cap_chan_timeout()->l2cap_sock_close_cb()->l2cap_sock_kill()
B::l2cap_sock_release()->sock_orphan()
B::l2cap_sock_release()->l2cap_sock_kill()
where,
sock_orphan() clears "sk->sk_socket" and l2cap_sock_teardown_cb() marks
socket as SOCK_ZAPPED.
In l2cap_sock_kill(), there is an "if-statement" that checks if both
sock_orphan() and sock_teardown() has been run i.e. sk->sk_socket is NULL
and socket is marked as SOCK_ZAPPED. Socket is killed if the condition is
satisfied.
In the race condition, following occurs:
A::l2cap_chan_timeout()->l2cap_chan_close()->l2cap_sock_teardown_cb()
B::l2cap_sock_release()->sock_orphan()
B::l2cap_sock_release()->l2cap_sock_kill()
A::l2cap_chan_timeout()->l2cap_sock_close_cb()->l2cap_sock_kill()
In this scenario, "if-statement" is true in both B::l2cap_sock_kill() and
A::l2cap_sock_kill() and we hit "refcount: underflow; use-after-free" bug.
Similar condition occurs at other places where teardown/sock_kill is
happening:
l2cap_disconnect_rsp()->l2cap_chan_del()->l2cap_sock_teardown_cb()
l2cap_disconnect_rsp()->l2cap_sock_close_cb()->l2cap_sock_kill()
l2cap_conn_del()->l2cap_chan_del()->l2cap_sock_teardown_cb()
l2cap_conn_del()->l2cap_sock_close_cb()->l2cap_sock_kill()
l2cap_disconnect_req()->l2cap_chan_del()->l2cap_sock_teardown_cb()
l2cap_disconnect_req()->l2cap_sock_close_cb()->l2cap_sock_kill()
l2cap_sock_cleanup_listen()->l2cap_chan_close()->l2cap_sock_teardown_cb()
l2cap_sock_cleanup_listen()->l2cap_sock_kill()
Protect teardown/sock_kill and orphan/sock_kill by adding hold_lock on
l2cap channel to ensure that the socket is killed only after marked as
zapped and orphan.
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Variable icid is being rc is assigned with a value that is never
read. The assignment is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This enables the code to set the input MTU using the underline link
packet types when set to 0, previously this would likely be rejected by
the remote peer since it would be bellow the minimal of 48 for BR/EDR
or 23 for LE, that way it shall be safe to use 0 without causing any
side effects.
This is convenient for the likes of A2DP transport, see:
https://habr.com/en/post/456182/
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We used to take a lock in amp_physical_cfm() but then we moved it to
the caller function. Unfortunately the unlock on this error path was
overlooked so it leads to a double unlock.
Fixes: a514b17fab ("Bluetooth: Refactor locking in amp_physical_cfm")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This reverts commit c49a8682fc.
There are devices which require low connection intervals for usable operation
including keyboards and mice. Forcing a static connection interval for
these types of devices has an impact in latency and causes a regression.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Luiz Augusto von Dentz
Sungwoo Kim
Hawkins Jiawei
Zhengchao Shao
Maxim Mikityanskiy
Tetsuo Handa
Jakub Kicinski
Xiaohui Zhang
Christophe JAILLET
Minghao Chi (CGEL ZTE)
Archie Pusaka
Yu Liu
Kai Ye
Meng Yu
Bhaskar Chowdhury
Bastien Nocera
Jimmy Wahlberg
Gustavo A. R. Silva
Manish Mandlik
Konstantin Forostyan
YueHaibing
Howard Chung
Colin Ian King
Dan Carpenter
Marcel Holtmann