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>
For testing and qualification purposes it is useful to allow changing
the minimum encryption key size value that the host stack is going to
enforce. This adds a new debugfs setting min_encrypt_key_size to achieve
this functionality.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Pull networking updates from David Miller:
"Some highlights from this development cycle:
1) Big refactoring of ipv6 route and neigh handling to support
nexthop objects configurable as units from userspace. From David
Ahern.
2) Convert explored_states in BPF verifier into a hash table,
significantly decreased state held for programs with bpf2bpf
calls, from Alexei Starovoitov.
3) Implement bpf_send_signal() helper, from Yonghong Song.
4) Various classifier enhancements to mvpp2 driver, from Maxime
Chevallier.
5) Add aRFS support to hns3 driver, from Jian Shen.
6) Fix use after free in inet frags by allocating fqdirs dynamically
and reworking how rhashtable dismantle occurs, from Eric Dumazet.
7) Add act_ctinfo packet classifier action, from Kevin
Darbyshire-Bryant.
8) Add TFO key backup infrastructure, from Jason Baron.
9) Remove several old and unused ISDN drivers, from Arnd Bergmann.
10) Add devlink notifications for flash update status to mlxsw driver,
from Jiri Pirko.
11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.
12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.
13) Various enhancements to ipv6 flow label handling, from Eric
Dumazet and Willem de Bruijn.
14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
der Merwe, and others.
15) Various improvements to axienet driver including converting it to
phylink, from Robert Hancock.
16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.
17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
Radulescu.
18) Add devlink health reporting to mlx5, from Moshe Shemesh.
19) Convert stmmac over to phylink, from Jose Abreu.
20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
Shalom Toledo.
21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.
22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.
23) Track spill/fill of constants in BPF verifier, from Alexei
Starovoitov.
24) Support bounded loops in BPF, from Alexei Starovoitov.
25) Various page_pool API fixes and improvements, from Jesper Dangaard
Brouer.
26) Just like ipv4, support ref-countless ipv6 route handling. From
Wei Wang.
27) Support VLAN offloading in aquantia driver, from Igor Russkikh.
28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.
29) Add flower GRE encap/decap support to nfp driver, from Pieter
Jansen van Vuuren.
30) Protect against stack overflow when using act_mirred, from John
Hurley.
31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.
32) Use page_pool API in netsec driver, Ilias Apalodimas.
33) Add Google gve network driver, from Catherine Sullivan.
34) More indirect call avoidance, from Paolo Abeni.
35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.
36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.
37) Add MPLS manipulation actions to TC, from John Hurley.
38) Add sending a packet to connection tracking from TC actions, and
then allow flower classifier matching on conntrack state. From
Paul Blakey.
39) Netfilter hw offload support, from Pablo Neira Ayuso"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
net/mlx5e: Return in default case statement in tx_post_resync_params
mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
net: dsa: add support for BRIDGE_MROUTER attribute
pkt_sched: Include const.h
net: netsec: remove static declaration for netsec_set_tx_de()
net: netsec: remove superfluous if statement
netfilter: nf_tables: add hardware offload support
net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
net: flow_offload: add flow_block_cb_is_busy() and use it
net: sched: remove tcf block API
drivers: net: use flow block API
net: sched: use flow block API
net: flow_offload: add flow_block_cb_{priv, incref, decref}()
net: flow_offload: add list handling functions
net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
net: flow_offload: add flow_block_cb_setup_simple()
net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
...
The spec defines PSM and LE_PSM as different domains so a listen on the
same PSM is valid if the address type points to a different bearer.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Problem: The Linux Bluetooth stack yields complete control over the BLE
connection interval to the remote device.
The Linux Bluetooth stack provides access to the BLE connection interval
min and max values through /sys/kernel/debug/bluetooth/hci0/
conn_min_interval and /sys/kernel/debug/bluetooth/hci0/conn_max_interval.
These values are used for initial BLE connections, but the remote device
has the ability to request a connection parameter update. In the event
that the remote side requests to change the connection interval, the Linux
kernel currently only validates that the desired value is within the
acceptable range in the Bluetooth specification (6 - 3200, corresponding to
7.5ms - 4000ms). There is currently no validation that the desired value
requested by the remote device is within the min/max limits specified in
the conn_min_interval/conn_max_interval configurations. This essentially
leads to Linux yielding complete control over the connection interval to
the remote device.
The proposed patch adds a verification step to the connection parameter
update mechanism, ensuring that the desired value is within the min/max
bounds of the current connection. If the desired value is outside of the
current connection min/max values, then the connection parameter update
request is rejected and the negative response is returned to the remote
device. Recall that the initial connection is established using the local
conn_min_interval/conn_max_interval values, so this allows the Linux
administrator to retain control over the BLE connection interval.
The one downside that I see is that the current default Linux values for
conn_min_interval and conn_max_interval typically correspond to 30ms and
50ms respectively. If this change were accepted, then it is feasible that
some devices would no longer be able to negotiate to their desired
connection interval values. This might be remedied by setting the default
Linux conn_min_interval and conn_max_interval values to the widest
supported range (6 - 3200 / 7.5ms - 4000ms). This could lead to the same
behavior as the current implementation, where the remote device could
request to change the connection interval value to any value that is
permitted by the Bluetooth specification, and Linux would accept the
desired value.
Signed-off-by: Carey Sonsino <csonsino@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Fix minimum encryption key size check so that HCI_MIN_ENC_KEY_SIZE is
also allowed as stated in the comment.
This bug caused connection problems with devices having maximum
encryption key size of 7 octets (56-bit).
Fixes: 693cd8ce3f ("Bluetooth: Fix regression with minimum encryption key size alignment")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203997
Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When trying to align the minimum encryption key size requirement for
Bluetooth connections, it turns out doing this in a central location in
the HCI connection handling code is not possible.
Original Bluetooth version up to 2.0 used a security model where the
L2CAP service would enforce authentication and encryption. Starting
with Bluetooth 2.1 and Secure Simple Pairing that model has changed into
that the connection initiator is responsible for providing an encrypted
ACL link before any L2CAP communication can happen.
Now connecting Bluetooth 2.1 or later devices with Bluetooth 2.0 and
before devices are causing a regression. The encryption key size check
needs to be moved out of the HCI connection handling into the L2CAP
channel setup.
To achieve this, the current check inside hci_conn_security() has been
moved into l2cap_check_enc_key_size() helper function and then called
from four decisions point inside L2CAP to cover all combinations of
Secure Simple Pairing enabled devices and device using legacy pairing
and legacy service security model.
Fixes: d5bb334a8e ("Bluetooth: Align minimum encryption key size for LE and BR/EDR connections")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203643
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
l2cap_le_flowctl_init was reseting the tx_credits which works only for
outgoing connection since that set the tx_credits on the response, for
incoming connections that was not the case which leaves the channel
without any credits causing it to be suspended.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.20+
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch fixes the following warnings:
net/bluetooth/rfcomm/core.c:479:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
net/bluetooth/l2cap_core.c:4223:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The function l2cap_get_conf_opt will return L2CAP_CONF_OPT_SIZE + opt->len
as length value. The opt->len however is in control over the remote user
and can be used by an attacker to gain access beyond the bounds of the
actual packet.
To prevent any potential leak of heap memory, it is enough to check that
the resulting len calculation after calling l2cap_get_conf_opt is not
below zero. A well formed packet will always return >= 0 here and will
end with the length value being zero after the last option has been
parsed. In case of malformed packets messing with the opt->len field the
length value will become negative. If that is the case, then just abort
and ignore the option.
In case an attacker uses a too short opt->len value, then garbage will
be parsed, but that is protected by the unknown option handling and also
the option parameter size checks.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When doing option parsing for standard type values of 1, 2 or 4 octets,
the value is converted directly into a variable instead of a pointer. To
avoid being tricked into being a pointer, check that for these option
types that sizes actually match. In L2CAP every option is fixed size and
thus it is prudent anyway to ensure that the remote side sends us the
right option size along with option paramters.
If the option size is not matching the option type, then that option is
silently ignored. It is a protocol violation and instead of trying to
give the remote attacker any further hints just pretend that option is
not present and proceed with the default values. Implementation
following the specification and its qualification procedures will always
use the correct size and thus not being impacted here.
To keep the code readable and consistent accross all options, a few
cosmetic changes were also required.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Add the result values specific to L2CAP LE credit based connections
and change the old result values wherever they were used.
Signed-off-by: Mallikarjun Phulari <mallikarjun.phulari@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the remote is not able to fully utilize the MPS choosen recalculate
the credits based on the actual amount it is sending that way it can
still send packets of MTU size without credits dropping to 0.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Give enough rx credits for a full packet instead of using an arbitrary
number which may not be enough depending on the MTU and MPS which can
cause interruptions while waiting for more credits, also remove
debugfs entry for l2cap_le_max_credits.
With these changes the credits are restored after each SDU is received
instead of using fixed threshold, this way it is garanteed that there
will always be enough credits to send a packet without waiting more
credits to arrive.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This ensures the MPS can fit in a single HCI fragment so each
segment don't have to be reassembled at HCI level, in addition to
that also remove the debugfs entry to configure the MPS.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the function l2cap_parse_conf_rsp and in the function
l2cap_parse_conf_req the following variable is declared without
initialization:
struct l2cap_conf_efs efs;
In addition, when parsing input configuration parameters in both of
these functions, the switch case for handling EFS elements may skip the
memcpy call that will write to the efs variable:
...
case L2CAP_CONF_EFS:
if (olen == sizeof(efs))
memcpy(&efs, (void *)val, olen);
...
The olen in the above if is attacker controlled, and regardless of that
if, in both of these functions the efs variable would eventually be
added to the outgoing configuration request that is being built:
l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), (unsigned long) &efs);
So by sending a configuration request, or response, that contains an
L2CAP_CONF_EFS element, but with an element length that is not
sizeof(efs) - the memcpy to the uninitialized efs variable can be
avoided, and the uninitialized variable would be returned to the
attacker (16 bytes).
This issue has been assigned CVE-2017-1000410
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Ben Seri <ben@armis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Validate the output buffer length for L2CAP config requests and responses
to avoid overflowing the stack buffer used for building the option blocks.
Cc: stable@vger.kernel.org
Signed-off-by: Ben Seri <ben@armis.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_put, __skb_put };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_put, __skb_put };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
which actually doesn't cover pskb_put since there are only three
users overall.
A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.
An spatch similar to the one for skb_put_zero() converts many
of the places using it:
@@
identifier p, p2;
expression len, skb, data;
type t, t2;
@@
(
-p = skb_put(skb, len);
+p = skb_put_data(skb, data, len);
|
-p = (t)skb_put(skb, len);
+p = skb_put_data(skb, data, len);
)
(
p2 = (t2)p;
-memcpy(p2, data, len);
|
-memcpy(p, data, len);
)
@@
type t, t2;
identifier p, p2;
expression skb, data;
@@
t *p;
...
(
-p = skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
|
-p = (t *)skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
)
(
p2 = (t2)p;
-memcpy(p2, data, sizeof(*p));
|
-memcpy(p, data, sizeof(*p));
)
@@
expression skb, len, data;
@@
-memcpy(skb_put(skb, len), data, len);
+skb_put_data(skb, data, len);
(again, manually post-processed to retain some comments)
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consolidate code sending data to LE CoC channels and adds proper
accounting of packets sent, the remaining credits and how many packets
are queued.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Just keep queueing them into TX queue since the caller might just have
to do the same and there is no impact in adding another packet to the
TX queue even if there aren't any credits to transmit them.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Since we need to change the implementation, stop exposing internals.
Provide kref_read() to read the current reference count; typically
used for debug messages.
Kills two anti-patterns:
atomic_read(&kref->refcount)
kref->refcount.counter
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
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>
copy_from_iter_full(), copy_from_iter_full_nocache() and
csum_and_copy_from_iter_full() - counterparts of copy_from_iter()
et.al., advancing iterator only in case of successful full copy
and returning whether it had been successful or not.
Convert some obvious users. *NOTE* - do not blindly assume that
something is a good candidate for those unless you are sure that
not advancing iov_iter in failure case is the right thing in
this case. Anything that does short read/short write kind of
stuff (or is in a loop, etc.) is unlikely to be a good one.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The hci_get_route() API is used to look up local HCI devices, however
so far it has been incapable of dealing with anything else than the
public address of HCI devices. This completely breaks with LE-only HCI
devices that do not come with a public address, but use a static
random address instead.
This patch exteds the hci_get_route() API with a src_type parameter
that's used for comparing with the right address of each HCI device.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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>
The HCI_BREDR naming is confusing since it actually stands for Primary
Bluetooth Controller. Which is a term that has been used in the latest
standard. However from a legacy point of view there only really have
been Basic Rate (BR) and Enhanced Data Rate (EDR). Recent versions of
Bluetooth introduced Low Energy (LE) and made this terminology a little
bit confused since Dual Mode Controllers include BR/EDR and LE. To
simplify this the name HCI_PRIMARY stands for the Primary Controller
which can be a single mode or dual mode controller.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The LE dynamic PSM range is different from BR/EDR (0x0080 - 0x00ff)
and doesn't have requirements relating to parity, so separate checks
are needed.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Remove unneeded variable used to store return value.
Error reported by coccicheck.
Signed-off-by: Prasanna Karthik <mkarthi3@visteon.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The hci_connect_le_scan() is (as the name implies) a master/central
role API, so it makes no sense in passing a role parameter to it. At
the same time this patch also fixes the direct advertising support for
LE L2CAP sockets where we now call the more appropriate hci_le_connect()
API if slave/peripheral role is desired.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving a connect response we should make sure that the DCID is
within the valid range and that we don't already have another channel
allocated for the same DCID.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The 'dyn_end' value is also a valid CID so it should be included in
the range of values checked.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The core spec defines specific response codes for situations when the
received CID is incorrect. Add the defines for these and return them
as appropriate from the LE Connect Request handler function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Currently, when trying to connect to already paired device that just
rotated its RPA MAC address, old address would be used and connection
would fail. In order to fix that, kernel must scan and receive
advertisement with fresh RPA before connecting.
This patch enables new connection establishment procedure. Instead of just
sending HCI_OP_LE_CREATE_CONN to controller, "connect" will add device to
kernel whitelist and start scan. If advertisement is received, it'll be
compared against whitelist and then trigger connection if it matches.
That fixes mentioned reconnect issue for already paired devices. It also
make whole connection procedure more robust. We can try to connect to
multiple devices at same time now, even though controller allow only one.
Signed-off-by: Jakub Pawlowski <jpawlowski@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the user->list is deleted with list_del(), it doesn't initialize the
entry which can cause the issue with list_empty(). According to the
comment from the list.h, list_empty() returns false even if the list is
empty and put the entry in an undefined state.
/**
* list_del - deletes entry from list.
* @entry: the element to delete from the list.
* Note: list_empty() on entry does not return true after this, the entry is
* in an undefined state.
*/
Because of this behavior, list_empty() returns false even if list is empty
when the device is reconnected.
So, user->list needs to be re-initialized after list_del(). list.h already
have a macro list_del_init() which deletes the entry and initailze it again.
Signed-off-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
list_del() poisons pointers with special values, no need to overwrite them.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The return value of l2cap_recv_acldata() and sco_recv_scodata()
are not used, then change it to return void
Signed-off-by: Arron Wang <arron.wang@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We're getting very close to the maximum possible size of bt_skb_cb. To
prepare to shrink the struct with the help of a union this patch moves
all L2CAP related variables into the l2cap_ctrl struct. To later add
other 'ctrl' structs the L2CAP one is renamed simple 'l2cap' instead
of 'control'.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the extension of hdev->dev_flags utilizing a bitmap now, the space
is no longer restricted. Merge the hdev->dbg_flags into hdev->dev_flags
to save space on 64-bit architectures. On 32-bit architectures no size
reduction happens.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Instead of manually coding test_bit on hdev->dev_flags all the time,
use hci_dev_test_flag helper macro.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
This patch moves all the disconn_cfm callbacks to be based on the hci_cb
list. This means making l2cap_disconn_cfm private to l2cap_core.c and
sco_conn_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch moves all the connect_cfm callbacks to be based on the hci_cb
list. This means making l2cap_connect_cfm private to l2cap_core.c and
sco_connect_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no reason to have the custom hci_proto_auth/encrypt_cfm helpers
when the hci_cb list works equally well. This patch adds L2CAP to the
hci_cb list and makes l2cap_security_cfm a private function of
l2cap_core.c.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
On BR/EDR the L2CAP channel instances for fixed channels have so far
been marked as ready only once the L2CAP information req/rsp procedure
is complete and we have the fixed channel mask. This could however lead
to data being dropped if we receive it on the channel before knowing the
remote mask.
Since it is valid for a remote to send data this early, simply assume
that the channel is supported when we receive data on it. So far this
hasn't been noticed much because of limited use of fixed channels on
BR/EDR, but e.g. with SMP over BR/EDR this is already now visible with
automated tests failing randomly.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The comparing of chan->src should always be done against the local
identity address, represented by hcon->src and hcon->src_type. This
patch modifies l2cap_global_fixed_chan() to take the full hci_conn so
that we can easily compare against hcon->src and hcon->src_type.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The current bdaddr_type() usage in l2cap_core.c is a bit funny in that
it's always passed a hci_conn + a hci_conn member. Because of this only
the hci_conn is really needed. Since the second parameter is always
either hcon->src_type or hcon->dst type this patch adds two helper
functions for each purpose: bdaddr_src_type() and bdaddr_dst_type().
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The devices address types are BR/EDR Public, LE Public and LE Random and
any of these three is valid for L2CAP connections. So show the correct
type in the debugfs list.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Testing cross-transport pairing that starts on BR/EDR is only valid when
using a controller with BR/EDR Secure Connections. Devices will indicate
this by providing BR/EDR SMP fixed channel over L2CAP. To allow testing
of this feature on Bluetooth 4.0 controller or controllers without the
BR/EDR Secure Connections features, introduce a force_bredr_smp debugfs
option that allows faking the required AES connection.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Just use copy_from_iter(). That's what this method is trying to do
in all cases, in a very convoluted fashion.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
it'll die soon enough - now that kvec-backed iov_iter works regardless
of set_fs(), both instances will become copy_from_iter() as soon as
we introduce ->msg_iter...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The SMP over BR/EDR support for cross-transport pairing should also be
enabled when the debugfs setting force_lesc_support has been enabled.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When doing SMP over BR/EDR some of the routines can be shared with the
LE functionality whereas others needs to be split into their own BR/EDR
specific branches. This patch implements the split of BR/EDR specific
SMP code from the LE-only code, making sure SMP over BR/EDR works as
specified.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To pave the way for future fixed channels to be added easily we should
track both the local and remote mask on a per-L2CAP connection (struct
l2cap_conn) basis. So far the code has used a global variable in a racy
way which anyway needs fixing.
This patch renames the existing conn->fixed_chan_mask that tracked
the remote mask to conn->remote_fixed_chan and adds a new variable
conn->local_fixed_chan to track the local mask. Since the HS support
info is now available in the local mask we can remove the
conn->hs_enabled variable.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth spec states that automatically flushable packets may not
be sent over a LE-U link.
Signed-off-by: Steven Walter <stevenrwalter@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
This patch adds some extra debug logs to L2CAP related code. These are
mainly to help track locking issues but will probably be useful for
debugging other types of issues as well.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The insufficient authentication/encryption errors indicate to the L2CAP
client that it should try to elevate the security level. Since there
really isn't any exception to this rule it makes sense to fully handle
it on the kernel side instead of pushing the responsibility to user
space.
This patch adds special handling of these two error codes and calls
smp_conn_security() with the elevated security level if necessary.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
So far smp_sufficient_security() has returned false if we're encrypted
with an STK but do have an LTK available. However, for the sake of LE
CoC servers we do want to let the incoming connection through even
though we're only encrypted with the STK.
This patch adds a key preference parameter to smp_sufficient_security()
with two possible values (enum used instead of bool for readability).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For LE CoC L2CAP servers we don't do security level elevation during the
BT_CONNECT2 state (instead LE CoC simply sends an immediate error
response if the security level isn't high enough). Therefore if we get a
security level change while an LE CoC channel is in the BT_CONNECT2
state we should simply do nothing.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no reason why all users of L2CAP would need to worry about
initializing chan->nesting to L2CAP_NESTING_NORMAL (which is important
since 0 is the same as NESTING_SMP). This patch moves the initialization
to the common place that's used to create all new channels, i.e. the
l2cap_chan_create() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the error case where credits is greater than max_credits there
is a missing l2cap_chan_unlock before returning.
Signed-off-by: Martin Townsend <mtownsend1973@gmail.com>
Tested-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The values of a lot of the mgmt_device_connected() parameters come
straight from a hci_conn object. We can simplify the function by passing
the full hci_conn pointer to it.
Signed-off-by: Alfonso Acosta <fons@spotify.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The L2CAP connection's channel list lock (conn->chan_lock) must never be
taken while already holding a channel lock (chan->lock) in order to
avoid lock-inversion and lockdep warnings. So far the l2cap_chan_connect
function has acquired the chan->lock early in the function and then
later called l2cap_chan_add(conn, chan) which will try to take the
conn->chan_lock. This violates the correct order of taking the locks and
may lead to the following type of lockdep warnings:
-> #1 (&conn->chan_lock){+.+...}:
[<c109324d>] lock_acquire+0x9d/0x140
[<c188459c>] mutex_lock_nested+0x6c/0x420
[<d0aab48e>] l2cap_chan_add+0x1e/0x40 [bluetooth]
[<d0aac618>] l2cap_chan_connect+0x348/0x8f0 [bluetooth]
[<d0cc9a91>] lowpan_control_write+0x221/0x2d0 [bluetooth_6lowpan]
-> #0 (&chan->lock){+.+.+.}:
[<c10928d8>] __lock_acquire+0x1a18/0x1d20
[<c109324d>] lock_acquire+0x9d/0x140
[<c188459c>] mutex_lock_nested+0x6c/0x420
[<d0ab05fd>] l2cap_connect_cfm+0x1dd/0x3f0 [bluetooth]
[<d0a909c4>] hci_le_meta_evt+0x11a4/0x1260 [bluetooth]
[<d0a910eb>] hci_event_packet+0x3ab/0x3120 [bluetooth]
[<d0a7cb08>] hci_rx_work+0x208/0x4a0 [bluetooth]
CPU0 CPU1
---- ----
lock(&conn->chan_lock);
lock(&chan->lock);
lock(&conn->chan_lock);
lock(&chan->lock);
Before calling l2cap_chan_add() the channel is not part of the
conn->chan_l list, and can therefore only be accessed by the L2CAP user
(such as l2cap_sock.c). We can therefore assume that it is the
responsibility of the user to handle mutual exclusion until this point
(which we can see is already true in l2cap_sock.c by it in many places
touching chan members without holding chan->lock).
Since the hci_conn and by exctension l2cap_conn creation in the
l2cap_chan_connect() function depend on chan details we cannot simply
add a mutex_lock(&conn->chan_lock) in the beginning of the function
(since the conn object doesn't yet exist there). What we can do however
is move the chan->lock taking later into the function where we already
have the conn object and can that way take conn->chan_lock first.
This patch implements the above strategy and does some other necessary
changes such as using __l2cap_chan_add() which assumes conn->chan_lock
is held, as well as adding a second needed label so the unlocking
happens as it should.
Reported-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Even if we have no connection-oriented channels we should perform the
L2CAP Information Request procedures before notifying L2CAP channels of
the connection. This is so that the L2CAP channel implementations can
perform checks on what the remote side supports (e.g. does it support
the fixed channel in question).
So far the code has relied on the l2cap_do_start() function to initiate
the Information Request, however l2cap_do_start() is used on a
per-channel basis and only for connection-oriented channels. This means
that if there are no connection-oriented channels on the system we would
never start the Information Request procedure.
This patch creates a new l2cap_request_info() helper function to
initiate the Information Request procedure, and ensures that it is
called whenever a BR/EDR connection has been established. The patch also
updates fixed channels to be notified of connection readiness only once
the Information Request procedure has completed.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The identity address update of all channels for an l2cap_conn needs to
take the lock for each channel, i.e. it's safest to do this by a
separate workqueue callback.
Previously this was partially solved by moving the entire SMP key
distribution behind a workqueue. However, if we want SMP context locking
to be correct and safe we should always use the l2cap_chan lock when
accessing it, meaning even smp_distribute_keys needs to take that lock
which would once again create a dead lock when updating the identity
address.
The simplest way to solve this is to have l2cap_conn manage the deferred
work which is what this patch does. A subsequent patch will remove the
now unnecessary SMP key distribution work struct.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The "pending" L2CAP response value is not defined for LE CoC. This patch
adds a clarifying comment to the code so that the reader will not think
there is a bug in trying to use this value for LE CoC.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that there are no more users of the l2cap_conn_shutdown API (since
smp.c switched to using hci_disconnect) we can simply remove it along
with all of it's l2cap_conn variables.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When the l2cap_conn_del() function is used we do not want to wait around
"in case something happens" before disconnecting. This patch sets the
disconnection timeout to 0 so that the disconnection routines get
immediately scheduled.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
It's natural to have *_get() functions that increment the reference
count of an object to return the object type itself. This way it's
simple to make a copy of the object pointer and increase the reference
count in a single step. This patch updates two such get() functions,
namely hci_conn_get() and l2cap_conn_get(), and updates the users to
take advantage of the new API.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that SMP has been converted to use fixed channels we've got a bit of
a problem with the hci_conn reference counting. So far the L2CAP code
has kept a reference for each L2CAP channel that was notified of the
connection. With SMP however this would mean that the connection is
never dropped even though there are no other users of it. Furthermore,
SMP already does its own hci_conn reference counting internally,
starting from a security or pairing request and ending with the key
distribution.
This patch makes L2CAP fixed channels default to the L2CAP core not
keeping a hci_conn reference for them. A new FLAG_HOLD_HCI_CONN flag is
added so that L2CAP users can declare an exception to this rule and hold
a reference even for their fixed channels. One such exception is the
L2CAP socket layer which does want a reference for each socket (e.g. an
ATT socket which uses a fixed channel).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The l2cap_chan_add() function doesn't require the channel to be
unlocked. It only requires the l2cap_conn to be unlocked. Therefore,
it's unnecessary to unlock a channel before calling l2cap_chan_add().
This patch removes such unnecessary unlocking from the
l2cap_chan_connect() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The l2cap_create_le_flowctl_pdu() function that l2cap_segment_le_sdu()
calls is perfectly capable of doing packet fragmentation if given bigger
PDUs than the HCI buffers allow. Forcing the PDU length based on the HCI
MTU (conn->mtu) would therefore needlessly strict operation on hardware
with limited LE buffers (e.g. both Intel and Broadcom seem to have this
set to just 27 bytes).
This patch removes the restriction and makes it possible to send PDUs of
the full length that the remote MPS value allows.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
I-Frame which is going to be resend already has FCS field added and set
(if it was required). Adding additional FCS field calculated from data +
old FCS in resend function is incorrect. This patch fix that.
Issue has been found during PTS testing.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There is no need to decrease pdu size with L2CAP SDU lenght in Start
L2CAP SDU frame. Start packtet is just 2 bytes longer as specified and
we can keep payload as long as possible.
When testing SAR L2CAP against PTS, L2CAP channel is usually configured
in that way, that SDU = MPS * 3. PTS expets then 3 I-Frames from IUT: Start,
Continuation and End frame.
Without this fix, we sent 4 I-Frames. We could pass a test by using -b
option in l2test and send just two bytes less than SDU length. With this
patch no need to use -b option.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
