Commit Graph

266 Commits

Author SHA1 Message Date
Luiz Augusto von Dentz 464c702fb9 Bluetooth: Init sk_peer_* on bt_sock_alloc
This makes sure peer information is always available via sock when using
bt_sock_alloc.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2023-08-11 11:37:22 -07:00
Luiz Augusto von Dentz 6bfa273e53 Bluetooth: Consolidate code around sk_alloc into a helper function
This consolidates code around sk_alloc into bt_sock_alloc which does
take care of common initialization.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2023-08-11 11:36:50 -07:00
Sungwoo Kim 1728137b33 Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cb
l2cap_sock_release(sk) frees sk. However, sk's children are still alive
and point to the already free'd sk's address.
To fix this, l2cap_sock_release(sk) also cleans sk's children.

==================================================================
BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650
Read of size 8 at addr ffff888104617aa8 by task kworker/u3:0/276

CPU: 0 PID: 276 Comm: kworker/u3:0 Not tainted 6.2.0-00001-gef397bd4d5fb-dirty #59
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci2 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x72/0x95 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:306 [inline]
 print_report+0x175/0x478 mm/kasan/report.c:417
 kasan_report+0xb1/0x130 mm/kasan/report.c:517
 l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650
 l2cap_chan_ready+0x10e/0x1e0 net/bluetooth/l2cap_core.c:1386
 l2cap_config_req+0x753/0x9f0 net/bluetooth/l2cap_core.c:4480
 l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5739 [inline]
 l2cap_sig_channel net/bluetooth/l2cap_core.c:6509 [inline]
 l2cap_recv_frame+0xe2e/0x43c0 net/bluetooth/l2cap_core.c:7788
 l2cap_recv_acldata+0x6ed/0x7e0 net/bluetooth/l2cap_core.c:8506
 hci_acldata_packet net/bluetooth/hci_core.c:3813 [inline]
 hci_rx_work+0x66e/0xbc0 net/bluetooth/hci_core.c:4048
 process_one_work+0x4ea/0x8e0 kernel/workqueue.c:2289
 worker_thread+0x364/0x8e0 kernel/workqueue.c:2436
 kthread+0x1b9/0x200 kernel/kthread.c:376
 ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308
 </TASK>

Allocated by task 288:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x82/0x90 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:968 [inline]
 __kmalloc+0x5a/0x140 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 sk_prot_alloc+0x113/0x1f0 net/core/sock.c:2040
 sk_alloc+0x36/0x3c0 net/core/sock.c:2093
 l2cap_sock_alloc.constprop.0+0x39/0x1c0 net/bluetooth/l2cap_sock.c:1852
 l2cap_sock_create+0x10d/0x220 net/bluetooth/l2cap_sock.c:1898
 bt_sock_create+0x183/0x290 net/bluetooth/af_bluetooth.c:132
 __sock_create+0x226/0x380 net/socket.c:1518
 sock_create net/socket.c:1569 [inline]
 __sys_socket_create net/socket.c:1606 [inline]
 __sys_socket_create net/socket.c:1591 [inline]
 __sys_socket+0x112/0x200 net/socket.c:1639
 __do_sys_socket net/socket.c:1652 [inline]
 __se_sys_socket net/socket.c:1650 [inline]
 __x64_sys_socket+0x40/0x50 net/socket.c:1650
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Freed by task 288:
 kasan_save_stack+0x22/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:523
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free mm/kasan/common.c:200 [inline]
 __kasan_slab_free+0x10a/0x190 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3787 [inline]
 __kmem_cache_free+0x88/0x1f0 mm/slub.c:3800
 sk_prot_free net/core/sock.c:2076 [inline]
 __sk_destruct+0x347/0x430 net/core/sock.c:2168
 sk_destruct+0x9c/0xb0 net/core/sock.c:2183
 __sk_free+0x82/0x220 net/core/sock.c:2194
 sk_free+0x7c/0xa0 net/core/sock.c:2205
 sock_put include/net/sock.h:1991 [inline]
 l2cap_sock_kill+0x256/0x2b0 net/bluetooth/l2cap_sock.c:1257
 l2cap_sock_release+0x1a7/0x220 net/bluetooth/l2cap_sock.c:1428
 __sock_release+0x80/0x150 net/socket.c:650
 sock_close+0x19/0x30 net/socket.c:1368
 __fput+0x17a/0x5c0 fs/file_table.c:320
 task_work_run+0x132/0x1c0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x113/0x120 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x21/0x50 kernel/entry/common.c:296
 do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The buggy address belongs to the object at ffff888104617800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 680 bytes inside of
 1024-byte region [ffff888104617800, ffff888104617c00)

The buggy address belongs to the physical page:
page:00000000dbca6a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888104614000 pfn:0x104614
head:00000000dbca6a80 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0
flags: 0x200000000010200(slab|head|node=0|zone=2)
raw: 0200000000010200 ffff888100041dc0 ffffea0004212c10 ffffea0004234b10
raw: ffff888104614000 0000000000080002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888104617980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888104617a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888104617a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888104617b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888104617b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Ack: This bug is found by FuzzBT with a modified Syzkaller. Other
contributors are Ruoyu Wu and Hui Peng.
Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-29 10:48:35 -07:00
Luiz Augusto von Dentz df57033488 Bluetooth: L2CAP: Fix potential user-after-free
This fixes all instances of which requires to allocate a buffer calling
alloc_skb which may release the chan lock and reacquire later which
makes it possible that the chan is disconnected in the meantime.

Fixes: a6a5568c03 ("Bluetooth: Lock the L2CAP channel when sending")
Reported-by: Alexander Coffin <alex.coffin@matician.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2023-02-09 14:18:48 -08:00
Dan Carpenter 2b70d4f9b2 Bluetooth: L2CAP: uninitialized variables in l2cap_sock_setsockopt()
The "opt" variable is a u32, but on some paths only the top bytes
were initialized and the others contained random stack data.

Fixes: a7b75c5a8c ("net: pass a sockptr_t into ->setsockopt")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2022-01-07 08:40:11 +01:00
David S. Miller e63a023489 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-12-30

The following pull-request contains BPF updates for your *net-next* tree.

We've added 72 non-merge commits during the last 20 day(s) which contain
a total of 223 files changed, 3510 insertions(+), 1591 deletions(-).

The main changes are:

1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii.

2) Beautify and de-verbose verifier logs, from Christy.

3) Composable verifier types, from Hao.

4) bpf_strncmp helper, from Hou.

5) bpf.h header dependency cleanup, from Jakub.

6) get_func_[arg|ret|arg_cnt] helpers, from Jiri.

7) Sleepable local storage, from KP.

8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31 14:35:40 +00:00
Jakub Kicinski b6459415b3 net: Don't include filter.h from net/sock.h
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
2021-12-29 08:48:14 -08:00
Luiz Augusto von Dentz 30d5772273 Bluetooth: L2CAP: Fix using wrong mode
If user has a set to use SOCK_STREAM the socket would default to
L2CAP_MODE_ERTM which later needs to be adjusted if the destination
address is LE which doesn't support such mode.

Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2021-12-21 13:46:30 -08:00
Luiz Augusto von Dentz f5ff291098 Bluetooth: L2CAP: Fix not initializing sk_peer_pid
In order to group sockets being connected using L2CAP_MODE_EXT_FLOWCTL
the pid is used but sk_peer_pid was not being initialized as it is
currently only done for af_unix.

Fixes: b48596d1dc ("Bluetooth: L2CAP: Add get_peer_pid callback")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2021-10-12 17:31:43 +02:00
Wang ShaoBo 1bff51ea59 Bluetooth: fix use-after-free error in lock_sock_nested()
use-after-free error in lock_sock_nested is reported:

[  179.140137][ T3731] =====================================================
[  179.142675][ T3731] BUG: KMSAN: use-after-free in lock_sock_nested+0x280/0x2c0
[  179.145494][ T3731] CPU: 4 PID: 3731 Comm: kworker/4:2 Not tainted 5.12.0-rc6+ #54
[  179.148432][ T3731] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[  179.151806][ T3731] Workqueue: events l2cap_chan_timeout
[  179.152730][ T3731] Call Trace:
[  179.153301][ T3731]  dump_stack+0x24c/0x2e0
[  179.154063][ T3731]  kmsan_report+0xfb/0x1e0
[  179.154855][ T3731]  __msan_warning+0x5c/0xa0
[  179.155579][ T3731]  lock_sock_nested+0x280/0x2c0
[  179.156436][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.157257][ T3731]  l2cap_sock_teardown_cb+0xb8/0x890
[  179.158154][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.159141][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.159994][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.160959][ T3731]  ? l2cap_sock_recv_cb+0x420/0x420
[  179.161834][ T3731]  l2cap_chan_del+0x3e1/0x1d50
[  179.162608][ T3731]  ? kmsan_get_metadata+0x116/0x180
[  179.163435][ T3731]  ? kmsan_get_shadow_origin_ptr+0x84/0xb0
[  179.164406][ T3731]  l2cap_chan_close+0xeea/0x1050
[  179.165189][ T3731]  ? kmsan_internal_unpoison_shadow+0x42/0x70
[  179.166180][ T3731]  l2cap_chan_timeout+0x1da/0x590
[  179.167066][ T3731]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[  179.168023][ T3731]  ? l2cap_chan_create+0x560/0x560
[  179.168818][ T3731]  process_one_work+0x121d/0x1ff0
[  179.169598][ T3731]  worker_thread+0x121b/0x2370
[  179.170346][ T3731]  kthread+0x4ef/0x610
[  179.171010][ T3731]  ? process_one_work+0x1ff0/0x1ff0
[  179.171828][ T3731]  ? kthread_blkcg+0x110/0x110
[  179.172587][ T3731]  ret_from_fork+0x1f/0x30
[  179.173348][ T3731]
[  179.173752][ T3731] Uninit was created at:
[  179.174409][ T3731]  kmsan_internal_poison_shadow+0x5c/0xf0
[  179.175373][ T3731]  kmsan_slab_free+0x76/0xc0
[  179.176060][ T3731]  kfree+0x3a5/0x1180
[  179.176664][ T3731]  __sk_destruct+0x8af/0xb80
[  179.177375][ T3731]  __sk_free+0x812/0x8c0
[  179.178032][ T3731]  sk_free+0x97/0x130
[  179.178686][ T3731]  l2cap_sock_release+0x3d5/0x4d0
[  179.179457][ T3731]  sock_close+0x150/0x450
[  179.180117][ T3731]  __fput+0x6bd/0xf00
[  179.180787][ T3731]  ____fput+0x37/0x40
[  179.181481][ T3731]  task_work_run+0x140/0x280
[  179.182219][ T3731]  do_exit+0xe51/0x3e60
[  179.182930][ T3731]  do_group_exit+0x20e/0x450
[  179.183656][ T3731]  get_signal+0x2dfb/0x38f0
[  179.184344][ T3731]  arch_do_signal_or_restart+0xaa/0xe10
[  179.185266][ T3731]  exit_to_user_mode_prepare+0x2d2/0x560
[  179.186136][ T3731]  syscall_exit_to_user_mode+0x35/0x60
[  179.186984][ T3731]  do_syscall_64+0xc5/0x140
[  179.187681][ T3731]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  179.188604][ T3731] =====================================================

In our case, there are two Thread A and B:

Context: Thread A:              Context: Thread B:

l2cap_chan_timeout()            __se_sys_shutdown()
  l2cap_chan_close()              l2cap_sock_shutdown()
    l2cap_chan_del()                l2cap_chan_close()
      l2cap_sock_teardown_cb()        l2cap_sock_teardown_cb()

Once l2cap_sock_teardown_cb() excuted, this sock will be marked as SOCK_ZAPPED,
and can be treated as killable in l2cap_sock_kill() if sock_orphan() has
excuted, at this time we close sock through sock_close() which end to call
l2cap_sock_kill() like Thread C:

Context: Thread C:

sock_close()
  l2cap_sock_release()
    sock_orphan()
    l2cap_sock_kill()  #free sock if refcnt is 1

If C completed, Once A or B reaches l2cap_sock_teardown_cb() again,
use-after-free happened.

We should set chan->data to NULL if sock is destructed, for telling teardown
operation is not allowed in l2cap_sock_teardown_cb(), and also we should
avoid killing an already killed socket in l2cap_sock_close_cb().

Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2021-09-01 07:36:08 +02:00
Archie Pusaka 3af70b39fa Bluetooth: check for zapped sk before connecting
There is a possibility of receiving a zapped sock on
l2cap_sock_connect(). This could lead to interesting crashes, one
such case is tearing down an already tore l2cap_sock as is happened
with this call trace:

__dump_stack lib/dump_stack.c:15 [inline]
dump_stack+0xc4/0x118 lib/dump_stack.c:56
register_lock_class kernel/locking/lockdep.c:792 [inline]
register_lock_class+0x239/0x6f6 kernel/locking/lockdep.c:742
__lock_acquire+0x209/0x1e27 kernel/locking/lockdep.c:3105
lock_acquire+0x29c/0x2fb kernel/locking/lockdep.c:3599
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:137 [inline]
_raw_spin_lock_bh+0x38/0x47 kernel/locking/spinlock.c:175
spin_lock_bh include/linux/spinlock.h:307 [inline]
lock_sock_nested+0x44/0xfa net/core/sock.c:2518
l2cap_sock_teardown_cb+0x88/0x2fb net/bluetooth/l2cap_sock.c:1345
l2cap_chan_del+0xa3/0x383 net/bluetooth/l2cap_core.c:598
l2cap_chan_close+0x537/0x5dd net/bluetooth/l2cap_core.c:756
l2cap_chan_timeout+0x104/0x17e net/bluetooth/l2cap_core.c:429
process_one_work+0x7e3/0xcb0 kernel/workqueue.c:2064
worker_thread+0x5a5/0x773 kernel/workqueue.c:2196
kthread+0x291/0x2a6 kernel/kthread.c:211
ret_from_fork+0x4e/0x80 arch/x86/entry/entry_64.S:604

Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Reported-by: syzbot+abfc0f5e668d4099af73@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>
2021-03-23 16:03:48 +01:00
Luiz Augusto von Dentz f19425641c Bluetooth: L2CAP: Fix calling sk_filter on non-socket based channel
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>
2020-09-25 20:21:55 +02:00
Abhishek Pandit-Subedi 20ae4089d0 Bluetooth: Only mark socket zapped after unlocking
Since l2cap_sock_teardown_cb doesn't acquire the channel lock before
setting the socket as zapped, it could potentially race with
l2cap_sock_release which frees the socket. Thus, wait until the cleanup
is complete before marking the socket as zapped.

This race was reproduced on a JBL GO speaker after the remote device
rejected L2CAP connection due to resource unavailability.

Here is a dmesg log with debug logs from a repro of this bug:
[ 3465.424086] Bluetooth: hci_core.c:hci_acldata_packet() hci0 len 16 handle 0x0003 flags 0x0002
[ 3465.424090] Bluetooth: hci_conn.c:hci_conn_enter_active_mode() hcon 00000000cfedd07d mode 0
[ 3465.424094] Bluetooth: l2cap_core.c:l2cap_recv_acldata() conn 000000007eae8952 len 16 flags 0x2
[ 3465.424098] Bluetooth: l2cap_core.c:l2cap_recv_frame() len 12, cid 0x0001
[ 3465.424102] Bluetooth: l2cap_core.c:l2cap_raw_recv() conn 000000007eae8952
[ 3465.424175] Bluetooth: l2cap_core.c:l2cap_sig_channel() code 0x03 len 8 id 0x0c
[ 3465.424180] Bluetooth: l2cap_core.c:l2cap_connect_create_rsp() dcid 0x0045 scid 0x0000 result 0x02 status 0x00
[ 3465.424189] Bluetooth: l2cap_core.c:l2cap_chan_put() chan 000000006acf9bff orig refcnt 4
[ 3465.424196] Bluetooth: l2cap_core.c:l2cap_chan_del() chan 000000006acf9bff, conn 000000007eae8952, err 111, state BT_CONNECT
[ 3465.424203] Bluetooth: l2cap_sock.c:l2cap_sock_teardown_cb() chan 000000006acf9bff state BT_CONNECT
[ 3465.424221] Bluetooth: l2cap_core.c:l2cap_chan_put() chan 000000006acf9bff orig refcnt 3
[ 3465.424226] Bluetooth: hci_core.h:hci_conn_drop() hcon 00000000cfedd07d orig refcnt 6
[ 3465.424234] BUG: spinlock bad magic on CPU#2, kworker/u17:0/159
[ 3465.425626] Bluetooth: hci_sock.c:hci_sock_sendmsg() sock 000000002bb0cb64 sk 00000000a7964053
[ 3465.430330]  lock: 0xffffff804410aac0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[ 3465.430332] Causing a watchdog bite!

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reported-by: Balakrishna Godavarthi <bgodavar@codeaurora.org>
Reviewed-by: Manish Mandlik <mmandlik@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-09-13 09:46:00 +02:00
David S. Miller 4bb540dbe4 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
Johan Hedberg says:

====================
pull request: bluetooth-next 2020-07-31

Here's the main bluetooth-next pull request for 5.9:

 - Fix firmware filenames for Marvell chipsets
 - Several suspend-related fixes
 - Addedd mgmt commands for runtime configuration
 - Multiple fixes for Qualcomm-based controllers
 - Add new monitoring feature for mgmt
 - Fix handling of legacy cipher (E4) together with security level 4
 - Add support for Realtek 8822CE controller
 - Fix issues with Chinese controllers using fake VID/PID values
 - Multiple other smaller fixes & improvements
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-31 15:11:52 -07:00
Christoph Hellwig a7b75c5a8c net: pass a sockptr_t into ->setsockopt
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer.  This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Gustavo A. R. Silva 19186c7b45 Bluetooth: core: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-07-10 19:09:42 +02:00
Archie Pusaka 5b440676c1 Bluetooth: L2CAP: add support for waiting disconnection resp
Whenever we disconnect a L2CAP connection, we would immediately
report a disconnection event (EPOLLHUP) to the upper layer, without
waiting for the response of the other device.

This patch offers an option to wait until we receive a disconnection
response before reporting disconnection event, by using the "how"
parameter in l2cap_sock_shutdown(). Therefore, upper layer can opt
to wait for disconnection response by shutdown(sock, SHUT_WR).

This can be used to enforce proper disconnection order in HID,
where the disconnection of the interrupt channel must be complete
before attempting to disconnect the control channel.

Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-05-13 10:03:51 +02:00
Luiz Augusto von Dentz 3ee7b7cd83 Bluetooth: Add BT_MODE socket option
This adds BT_MODE socket option which can be used to set L2CAP modes,
including modes only supported over LE which were not supported using
the L2CAP_OPTIONS.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-04-02 08:25:19 +02:00
Luiz Augusto von Dentz b86b0b150f Bluetooth: L2CAP: Fix handling LE modes by L2CAP_OPTIONS
L2CAP_OPTIONS shall only be used with BR/EDR modes.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-04-02 08:25:19 +02:00
Luiz Augusto von Dentz b48596d1dc Bluetooth: L2CAP: Add get_peer_pid callback
This adds a callback to read the socket pid.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-03-24 09:48:00 +01:00
Dan Carpenter b354e6c10e Bluetooth: L2CAP: Fix a condition in l2cap_sock_recvmsg()
Smatch complains about the indenting:

    net/bluetooth/l2cap_sock.c:1027 l2cap_sock_recvmsg()
    warn: inconsistent indenting

It looks like this is supposed to be an "else if" condition.

Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-03-12 15:12:00 +01:00
Luiz Augusto von Dentz 4be5ca67d5 Bluetooth: L2CAP: Add module option to enable ECRED mode
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>
2020-03-08 10:05:40 +01:00
Luiz Augusto von Dentz 15f02b9105 Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode
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>
2020-03-08 10:05:40 +01:00
Luiz Augusto von Dentz a2a8b0b4ad Bluetooth: Fix crash when using new BT_PHY option
This fixes the invalid check for connected socket which causes the
following trace due to sco_pi(sk)->conn being NULL:

RIP: 0010:sco_sock_getsockopt+0x2ff/0x800 net/bluetooth/sco.c:966

L2CAP has also been fixed since it has the same problem.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-02-18 22:02:15 +01:00
Luiz Augusto von Dentz eab2404ba7 Bluetooth: Add BT_PHY socket option
This adds BT_PHY socket option (read-only) which can be used to read
the PHYs in use by the underline connection.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-02-14 19:15:30 +01:00
Hillf Danton 2a154903ce Bluetooth: prefetch channel before killing sock
Prefetch channel before killing sock in order to fix UAF like

 BUG: KASAN: use-after-free in l2cap_sock_release+0x24c/0x290 net/bluetooth/l2cap_sock.c:1212
 Read of size 8 at addr ffff8880944904a0 by task syz-fuzzer/9751

Reported-by: syzbot+c3c5bdea7863886115dc@syzkaller.appspotmail.com
Fixes: 6c08fc896b ("Bluetooth: Fix refcount use-after-free issue")
Cc: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2020-02-05 09:05:04 +01:00
Manish Mandlik 6c08fc896b Bluetooth: Fix refcount use-after-free issue
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>
2020-01-29 04:53:12 +01:00
Fugang Duan bbb69b37be Bluetooth: Add return check for L2CAP security level set
Add return check for security level set for socket interface since
stack will check the return value.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2019-04-23 18:09:07 +02:00
Arnd Bergmann c7cbdbf29f net: rework SIOCGSTAMP ioctl handling
The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.

Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-19 14:07:40 -07:00
Matthias Kaehlcke c4f5627f7e Bluetooth: Fix locking in bt_accept_enqueue() for BH context
With commit e163376220 ("Bluetooth: Handle bt_accept_enqueue() socket
atomically") lock_sock[_nested]() is used to acquire the socket lock
before manipulating the socket. lock_sock[_nested]() may block, which
is problematic since bt_accept_enqueue() can be called in bottom half
context (e.g. from rfcomm_connect_ind()):

[<ffffff80080d81ec>] __might_sleep+0x4c/0x80
[<ffffff800876c7b0>] lock_sock_nested+0x24/0x58
[<ffffff8000d7c27c>] bt_accept_enqueue+0x48/0xd4 [bluetooth]
[<ffffff8000e67d8c>] rfcomm_connect_ind+0x190/0x218 [rfcomm]

Add a parameter to bt_accept_enqueue() to indicate whether the
function is called from BH context, and acquire the socket lock
with bh_lock_sock_nested() if that's the case.

Also adapt all callers of bt_accept_enqueue() to pass the new
parameter:

- l2cap_sock_new_connection_cb()
  - uses lock_sock() to lock the parent socket => process context

- rfcomm_connect_ind()
  - acquires the parent socket lock with bh_lock_sock() => BH
    context

- __sco_chan_add()
  - called from sco_chan_add(), which is called from sco_connect().
    parent is NULL, hence bt_accept_enqueue() isn't called in this
    code path and we can ignore it
  - also called from sco_conn_ready(). uses bh_lock_sock() to acquire
    the parent lock => BH context

Fixes: e163376220 ("Bluetooth: Handle bt_accept_enqueue() socket atomically")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2019-01-22 09:51:20 +01:00
Linus Torvalds a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00
Christoph Hellwig 17112d8081 net/bluetooth: convert to ->poll_mask
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26 09:16:44 +02:00
Denys Vlasenko 9b2c45d479 net: make getname() functions return length rather than use int* parameter
Changes since v1:
Added changes in these files:
    drivers/infiniband/hw/usnic/usnic_transport.c
    drivers/staging/lustre/lnet/lnet/lib-socket.c
    drivers/target/iscsi/iscsi_target_login.c
    drivers/vhost/net.c
    fs/dlm/lowcomms.c
    fs/ocfs2/cluster/tcp.c
    security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

    text    data     bss      dec     hex filename
30108430 2633624  873672 33615726 200ef6e vmlinux.before.o
30108109 2633612  873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-12 14:15:04 -05:00
Mateusz Jurczyk d2ecfa765d Bluetooth: Add sockaddr length checks before accessing sa_family in bind and connect handlers
Verify that the caller-provided sockaddr structure is large enough to
contain the sa_family field, before accessing it in bind() and connect()
handlers of the Bluetooth sockets. Since neither syscall enforces a minimum
size of the corresponding memory region, very short sockaddrs (zero or one
byte long) result in operating on uninitialized memory while referencing
sa_family.

Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-06-29 14:37:57 +02:00
David Howells cdfbabfb2f net: Work around lockdep limitation in sockets that use sockets
Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

 (1) If the pagefault handler decides it needs to read pages from AFS, it
     calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
     creating a call requires the socket lock:

	mmap_sem must be taken before sk_lock-AF_RXRPC

 (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
     binds the underlying UDP socket whilst holding its socket lock.
     inet_bind() takes its own socket lock:

	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

 (3) Reading from a TCP socket into a userspace buffer might cause a fault
     and thus cause the kernel to take the mmap_sem, but the TCP socket is
     locked whilst doing this:

	sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks.  The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace.  This is
a limitation in the design of lockdep.

Fix the general case by:

 (1) Double up all the locking keys used in sockets so that one set are
     used if the socket is created by userspace and the other set is used
     if the socket is created by the kernel.

 (2) Store the kern parameter passed to sk_alloc() in a variable in the
     sock struct (sk_kern_sock).  This informs sock_lock_init(),
     sock_init_data() and sk_clone_lock() as to the lock keys to be used.

     Note that the child created by sk_clone_lock() inherits the parent's
     kern setting.

 (3) Add a 'kern' parameter to ->accept() that is analogous to the one
     passed in to ->create() that distinguishes whether kernel_accept() or
     sys_accept4() was the caller and can be passed to sk_alloc().

     Note that a lot of accept functions merely dequeue an already
     allocated socket.  I haven't touched these as the new socket already
     exists before we get the parameter.

     Note also that there are a couple of places where I've made the accepted
     socket unconditionally kernel-based:

	irda_accept()
	rds_rcp_accept_one()
	tcp_accept_from_sock()

     because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal.  I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 18:23:27 -08:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Daniel Borkmann dbb50887c8 Bluetooth: split sk_filter in l2cap_sock_recv_cb
During an audit for sk_filter(), we found that rx_busy_skb handling
in l2cap_sock_recv_cb() and l2cap_sock_recvmsg() looks not quite as
intended.

The assumption from commit e328140fda ("Bluetooth: Use event-driven
approach for handling ERTM receive buffer") is that errors returned
from sock_queue_rcv_skb() are due to receive buffer shortage. However,
nothing should prevent doing a setsockopt() with SO_ATTACH_FILTER on
the socket, that could drop some of the incoming skbs when handled in
sock_queue_rcv_skb().

In that case sock_queue_rcv_skb() will return with -EPERM, propagated
from sk_filter() and if in L2CAP_MODE_ERTM mode, wrong assumption was
that we failed due to receive buffer being full. From that point onwards,
due to the to-be-dropped skb being held in rx_busy_skb, we cannot make
any forward progress as rx_busy_skb is never cleared from l2cap_sock_recvmsg(),
due to the filter drop verdict over and over coming from sk_filter().
Meanwhile, in l2cap_sock_recv_cb() all new incoming skbs are being
dropped due to rx_busy_skb being occupied.

Instead, just use __sock_queue_rcv_skb() where an error really tells that
there's a receive buffer issue. Split the sk_filter() and enable it for
non-segmented modes at queuing time since at this point in time the skb has
already been through the ERTM state machine and it has been acked, so dropping
is not allowed. Instead, for ERTM and streaming mode, call sk_filter() in
l2cap_data_rcv() so the packet can be dropped before the state machine sees it.

Fixes: e328140fda ("Bluetooth: Use event-driven approach for handling ERTM receive buffer")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-08-24 16:55:04 +02:00
Amadeusz Sławiński 23bc6ab0a0 Bluetooth: Fix l2cap_sock_setsockopt() with optname BT_RCVMTU
When we retrieve imtu value from userspace we should use 16 bit pointer
cast instead of 32 as it's defined that way in headers. Fixes setsockopt
calls on big-endian platforms.

Signed-off-by: Amadeusz Sławiński <amadeusz.slawinski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2016-07-17 19:59:26 +02:00
Patrik Flykt a164cee111 Bluetooth: Allow setting BT_SECURITY_FIPS with setsockopt
Update the security level check to allow setting BT_SECURITY_FIPS for
an L2CAP socket.

Signed-off-by: Patrik Flykt <patrik.flykt@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-04-08 19:10:57 +02:00
Johan Hedberg a2342c5fe5 Bluetooth: L2CAP: Fix setting chan src info before adding PSM/CID
At least the l2cap_add_psm() routine depends on the source address
type being properly set to know what auto-allocation ranges to use, so
the assignment to l2cap_chan needs to happen before this.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-01-29 11:47:24 +01:00
Johan Hedberg 114f9f1e03 Bluetooth: L2CAP: Introduce proper defines for PSM ranges
Having proper defines makes the code a bit readable, it also avoids
duplicating hard-coded values since these are also needed when
auto-allocating PSM values (in a subsequent patch).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-01-29 11:47:24 +01:00
Dean Jenkins 9f7378a9d6 Bluetooth: l2cap_disconnection_req priority over shutdown
There is a L2CAP protocol race between the local peer and
the remote peer demanding disconnection of the L2CAP link.

When L2CAP ERTM is used, l2cap_sock_shutdown() can be called
from userland to disconnect L2CAP. However, there can be a
delay introduced by waiting for ACKs. During this waiting
period, the remote peer may have sent a Disconnection Request.
Therefore, recheck the shutdown status of the socket
after waiting for ACKs because there is no need to do
further processing if the connection has gone.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Harish Jenny K N <harish_kandiga@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-21 00:49:26 +02:00
Dean Jenkins 04ba72e6b2 Bluetooth: Reorganize mutex lock in l2cap_sock_shutdown()
This commit reorganizes the mutex lock and is now
only protecting l2cap_chan_close(). This is now consistent
with other places where l2cap_chan_close() is called.

If a conn connection exists, call
mutex_lock(&conn->chan_lock) before calling l2cap_chan_close()
to ensure other L2CAP protocol operations do not interfere.

Note that the conn structure has to be protected from being
freed as it is possible for the connection to be disconnected
whilst the locks are not held. This solution allows the mutex
lock to be used even when the connection has just been
disconnected.

This commit also reduces the scope of chan locking.

The only place where chan locking is needed is the call to
l2cap_chan_close(chan, 0) which if necessary closes the channel.
Therefore, move the l2cap_chan_lock(chan) and
l2cap_chan_lock(chan) locking calls to around
l2cap_chan_close(chan, 0).

This allows __l2cap_wait_ack(sk, chan) to be called with no
chan locks being held so L2CAP messaging over the ACL link
can be done unimpaired.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Harish Jenny K N <harish_kandiga@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-21 00:49:26 +02:00
Dean Jenkins e7456437c1 Bluetooth: Unwind l2cap_sock_shutdown()
l2cap_sock_shutdown() is designed to only action shutdown
of the channel when shutdown is not already in progress.
Therefore, reorganise the code flow by adding a goto
to jump to the end of function handling when shutdown is
already being actioned. This removes one level of code
indentation and make the code more readable.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Harish Jenny K N <harish_kandiga@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-21 00:49:26 +02:00
Dean Jenkins e432c72c46 Bluetooth: __l2cap_wait_ack() add defensive timeout
Add a timeout to prevent the do while loop running in an
infinite loop. This ensures that the channel will be
instructed to close within 10 seconds so prevents
l2cap_sock_shutdown() getting stuck forever.

Returns -ENOLINK when the timeout is reached. The channel
will be subequently closed and not all data will be ACK'ed.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-07-23 17:10:51 +02:00
Dean Jenkins cb02a25583 Bluetooth: __l2cap_wait_ack() use msecs_to_jiffies()
Use msecs_to_jiffies() instead of using HZ so that it
is easier to specify the time in milliseconds.

Also add a #define L2CAP_WAIT_ACK_POLL_PERIOD to specify the 200ms
polling period so that it is defined in a single place.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-07-23 17:10:51 +02:00
Dean Jenkins 451e4c6c6b Bluetooth: Add BT_DBG to l2cap_sock_shutdown()
Add helpful BT_DBG debug to l2cap_sock_shutdown()
and __l2cap_wait_ack() so that the code flow can
be analysed.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-07-23 17:10:51 +02:00
Dean Jenkins f65468f6e2 Bluetooth: Make __l2cap_wait_ack more efficient
Use chan->state instead of chan->conn because waiting
for ACK's is only possible in the BT_CONNECTED state.
Also avoids reference to the conn structure so makes
locking easier.

Only call __l2cap_wait_ack() when the needed condition
of chan->unacked_frames > 0 && chan->state == BT_CONNECTED
is true and convert the while loop to a do while loop.

__l2cap_wait_ack() change the function prototype to
pass in the chan variable as chan is already available
in the calling function l2cap_sock_shutdown(). Avoids
locking issues.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-07-23 17:10:51 +02:00
Dean Jenkins 2baea85dec Bluetooth: L2CAP ERTM shutdown protect sk and chan
During execution of l2cap_sock_shutdown() which might
sleep, the sk and chan structures can be in an unlocked
condition which potentially allows the structures to be
freed by other running threads. Therefore, there is a
possibility of a malfunction or memory reuse after being
freed.

Keep the sk and chan structures alive during the
execution of l2cap_sock_shutdown() by using their
respective hold and put functions. This allows the structures
to be freeable at the end of l2cap_sock_shutdown().

Signed-off-by: Kautuk Consul <Kautuk_Consul@mentor.com>
Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-07-23 17:10:50 +02:00
Eric W. Biederman 11aa9c28b4 net: Pass kern from net_proto_family.create to sk_alloc
In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:50:17 -04:00