commit 693cd8ce3f882524a5d06f7800dd8492411877b3 upstream.
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: d5bb334a8e17 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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>
Since the link_mode member of the hci_conn struct is a bit field and we
already have a flags member as well it makes sense to merge these two
together. This patch moves all used link_mode bits into corresponding
flags. To keep backwards compatibility with user space we still need to
provide a get_link_mode() helper function for the ioctl's that expect a
link_mode style value.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In this case the replacement by l2cap_chan_ready() doesn't change the code
flow, the same operations will executed plus two others that have no
effect: the use of the parent socket, that a non-oriented channel doesn't
have and the reset of conf_state, which is also fine since the connection
is ready at this point.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
commit 7c9cbd0b5e38a1672fcd137894ace3b042dfbf69 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit af3d5d1c87664a4f150fcf3534c6567cb19909b0 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 06e7e776ca4d36547e503279aeff996cbb292c16 upstream.
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>
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.
Change-Id: I752ed1c290ab195f579e547318bcc7b512ea5bf9
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>
The %pK restrictions are used to eliminate exposing kernel addresses.
When kptr_restrict is set to "0" there are no restrictions. When
kptr_restrict is set to "1", kernel pointers printed using the %pK
format specifier will be replaced with 0's unless the user has
CAP_SYSLOG. When kptr_restrict is set to "2", kernel pointers printed
using %pK will be replaced with 0's regardless of privileges.
Change-Id: Iacd8f7b7cdafed3a111507d3da899be9261ff09f
Signed-off-by: Dibyendu Roy <dibyen@codeaurora.org>
If there are unacknowledged frames during an ongoing L2CAP transfer and
if socket is shutdown, it will result in deadlock as locks are not
released before going to sleep.
The L2CAP receive thread will be waiting on locks to update unacknowledged
frame count, whereas socket shutdown thread will be sleeping till
unacknowledged count becomes 0 resulting in deadlock.
Change-Id: Id54c04afc4cd0d2adeb2fa69149a701fc4062ad2
Signed-off-by: Rupesh Tatiya <rtatiya@codeaurora.org>
The L2CAP sockets can use BR/EDR public, LE public and LE random
addresses for various combinations of source and destination
devices. So make sure that getsockname(), getpeername() and
accept() return the correct address type.
For this the address type of the source and destination is stored
with the L2CAP channel information. The stored address type is
not the one specific for the HCI protocol. It is the address
type used for the L2CAP sockets and the management interface.
The underlying HCI connections store the HCI address type. If
needed, it gets converted to the socket address type.
Change-Id: I7ae010722908ed794d4162c157fba6baac266fe1
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Git-commit: 4f1654e08464abad06487e173661cb73721d27a7
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Kamal Negi <kamaln@codeaurora.org>
response.
Check and inititiate, if necessary, authentication procedure for
the connection before sending l2cap connect response. For legacy
devices, this pacth will initiate authentication procedure in the
first l2cap connect request as legacy do not initiate authentication
after connection.
Change-Id: Ic788608452e8cac9e3eb1f71a2b63f671025d5f9
Signed-off-by: Kamal Negi <kamaln@codeaurora.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.
Change-Id: Iba211a180665c5f2fa2fa462f5d5c48e2d980a21
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Git-commit: 13cac15296afe7e42088ecfcd0f1d4b658248c46
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Kamal Negi <kamaln@codeaurora.org>
It is possible that during BT OFF operation the hcon
could be released from a tasklet context while we are
trying to send the l2cap disconnect req. Make sure
that hcon is valid before dereferencing it during
l2cap disconnect req.
CRs-fixed: 383345
Change-Id: Icb12c62560013b5ebb047c1c5d4bfe04b3a793ef
Signed-off-by: Sunny Kapdi <sunnyk@codeaurora.org>
__u16 sco_pkt_type is introduced to struct sockaddr_sco. It allows bitwise
selection of SCO/eSCO packet types. Currently those bits are:
0x0001 HV1 may be used.
0x0002 HV2 may be used.
0x0004 HV3 may be used.
0x0008 EV3 may be used.
0x0010 EV4 may be used.
0x0020 EV5 may be used.
0x0040 2-EV3 may be used.
0x0080 3-EV3 may be used.
0x0100 2-EV5 may be used.
0x0200 3-EV5 may be used.
This is similar to the Packet Type parameter in the HCI Setup Synchronous
Connection Command, except that we are not reversing the logic on the EDR bits.
This makes the use of sco_pkt_tpye forward portable for the use case of
white-listing packet types, which we expect will be the primary use case.
If sco_pkt_type is zero, or userspace uses the old struct sockaddr_sco,
then the default behavior is to allow all packet types.
Packet type selection is just a request made to the Bluetooth chipset, and
it is up to the link manager on the chipset to negiotiate and decide on the
actual packet types used. Furthermore, when a SCO/eSCO connection is eventually
made there is no way for the host stack to determine which packet type was used
(however it is possible to get the link type of SCO or eSCO).
sco_pkt_type is ignored for incoming SCO connections. It is possible
to add this in the future as a parameter to the Accept Synchronous Connection
Command, however its a little trickier because the kernel does not
currently preserve sockaddr_sco data between userspace calls to accept().
The most common use for sco_pkt_type will be to white-list only SCO packets,
which can be done with the hci.h constant SCO_ESCO_MASK.
This patch is motivated by broken Bluetooth carkits such as the Motorolo
HF850 (it claims to support eSCO, but will actually reject eSCO connections
after 5 seconds) and the 2007/2008 Infiniti G35/37 (fails to route audio
if a 2-EV5 packet type is negiotiated). With this patch userspace can maintain
a list of compatible packet types to workaround remote devices such as these.
Based on a patch by Marcel Holtmann.
Rebased to 2.6.39.
Change-Id: Ide1c89574fa4f6f1b9218282e1af17051eb86315
Signed-off-by: Nick Pelly <npelly@google.com>
The length check is invalid since the length varies with type of
info response.
This was introduced by the commit cb3b3152b2
Because of this, l2cap info rsp is not handled and command reject is sent.
> ACL data: handle 11 flags 0x02 dlen 16
L2CAP(s): Info rsp: type 2 result 0
Extended feature mask 0x00b8
Enhanced Retransmission mode
Streaming mode
FCS Option
Fixed Channels
< ACL data: handle 11 flags 0x00 dlen 10
L2CAP(s): Command rej: reason 0
Command not understood
Cc: stable@vger.kernel.org
Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
Signed-off-by: Chan-Yeol Park <chanyeol.park@samsung.com>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
There has been code in place to check that the L2CAP length header
matches the amount of data received, but many PDU handlers have not been
checking that the data received actually matches that expected by the
specific PDU. This patch adds passing the length header to the specific
handler functions and ensures that those functions fail cleanly in the
case of an incorrect amount of data.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The CID is fixed to L2CAP ATT channel and so there is no need to hand it
down to the handling function. Just use a constant instead.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Several sub-modules like HIDP, rfcomm, ... need to track l2cap
connections. The l2cap_conn->hcon->dev object is used as parent for sysfs
devices so the sub-modules need to be notified when the hci_conn object is
removed from sysfs.
As submodules normally use the l2cap layer, the l2cap_user objects are
registered there instead of on the underlying hci_conn object. This avoids
any direct dependency on the HCI layer and lets the l2cap core handle any
specifics.
This patch introduces l2cap_user objects which contain a "probe" and
"remove" callback. You can register them on any l2cap_conn object and if
it is active, the "probe" callback will get called. Otherwise, an error is
returned.
The l2cap_conn object will call your "remove" callback directly before it
is removed from user-space. This allows you to remove your submodules
_before_ the parent l2cap_conn and hci_conn object is removed.
At any time you can asynchronously unregister your l2cap_user object if
your submodule vanishes before the l2cap_conn object does.
There is no way around l2cap_user. If we want wire-protocols in the
kernel, we always want the hci_conn object as parent in the sysfs tree. We
cannot use a channel here since we might need multiple channels for a
single protocol.
But the problem is, we _must_ get notified when an l2cap_conn object is
removed. We cannot use reference-counting for object-removal! This is not
how it works. If a hardware is removed, we should immediately remove the
object from sysfs. Any other behavior would be inconsistent with the rest
of the system. Also note that device_del() might sleep, but it doesn't
wait for user-space or block very long. It only _unlinks_ the object from
sysfs and the whole device-tree. Everything else is handled by ref-counts!
This is exactly what the other sub-modules must do: unlink their devices
when the "remove" l2cap_user callback is called. They should not do any
cleanup or synchronous shutdowns.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
If we want to use l2cap_conn outside of l2cap_core.c, we need refcounting
for these objects. Otherwise, we cannot synchronize l2cap locks with
outside locks and end up with deadlocks.
Hence, introduce ref-counting for l2cap_conn objects. This doesn't affect
l2cap internals at all, as they use a direct synchronization.
We also keep a reference to the parent hci_conn for locking purposes as
l2cap_conn depends on this. This doesn't affect the connection itself but
only the lifetime of the (dead) object.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
This patch removes the status parameter of the l2cap_conn_add function.
The parameter 'status' is always 0.
Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
We use _get() and _put() for device ref-counting in the kernel. However,
hci_conn_put() is _not_ used for ref-counting, hence, rename it to
hci_conn_drop() so we can later fix ref-counting and introduce
hci_conn_put().
hci_conn_hold() and hci_conn_put() are currently used to manage how long a
connection should be held alive. When the last user drops the connection,
we spawn a delayed work that performs the disconnect. Obviously, this has
nothing to do with ref-counting for the _object_ but rather for the
keep-alive of the connection.
But we really _need_ proper ref-counting for the _object_ to allow
connection-users like rfcomm-tty, HIDP or others.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Remove code which cannot execute. l2cap_conn_add for AMP_LINK
might only be invoked when receiving data in l2cap_recv_acldata.
But this case is checked in the first statement there.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Make code more readable by changing CONF_NO_FCS_RECV which is read
as "No L2CAP FCS option received" to CONF_RECV_NO_FCS which means
"Received L2CAP option NO_FCS". This flag really means that we have
received L2CAP FRAME CHECK SEQUENCE (FCS) OPTION with value "No FCS".
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
If L2CAP_FEAT_FCS is not supported we sould miss EWS option
configuration because of break. Make code more readable by
combining FCS configuration in the single block.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Before starting quering remote AMP controllers make sure
that there is local active AMP controller.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
l2cap_send_disconn_req takes 3 parameters of which conn might be
derived from chan. Make this conversion inside l2cap_send_disconn_req.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
When receiving L2CAP Create Channel Request set the channel as
L2CAP_FCS_NONE. Then in "L2CAP Config req" following field will
be set: "FCS Option 0x00 (No FCS)". So by default High Speed
channels have no FCS.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
When receiving Physical Link Completed event we need to create L2CAP
channel with L2CAP Create Chan Request. Current code was sending
this command only if connection was pending (which is probably
needed in channel move case). If channel is not moved but created
Create Chan should be sent for outgoing channel which is checked
with BT_CONNECT flag.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Set chan->fcs to L2CAP_FCS_NONE only for new L2CAP channels
(not moved). Other side can still request to use FCS.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
local_amp_id is already set in l2cap_connect() which is called several
lines above.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Use helper instead of test_bit. This is the only place left using
test CONF_CONNECT_PEND flag.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Since we have started to use local_amp_id for local AMP
Controller Id it makes sense to rename ctrl_id to remote_amp_id
since it represents remote AMP controller Id.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Add processing L2CAP Create Chan Request. When channel is created
save associated high speed link hs_hcon.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
When deciding whether to send EFS configuration response with success,
check rather for existence of High Speed physical link hs_hcon then
ctrl_id. There might be cases when there is ctrl_id but high speed link
is not established yet.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Disconnect logical link for high speed channel hs_hchan
associated with L2CAP channel chan.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
After physical link is created logical link needs to be created.
The process starts after L2CAP channel is created and L2CAP
Configuration Response with result PENDING is received.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Matias Karhumaa
Marcel Holtmann
Johan Hedberg
Gustavo Padovan
Ben Seri
Dibyendu Roy
Rupesh Tatiya
Linux Build Service Account
Kamal Negi
Seung-Woo Kim
Lukasz Rymanowski
Sunny Kapdi
Nick Pelly
Jaganath Kanakkassery
Anderson Lizardo
David Herrmann
Claudio Takahasi
John W. Linville
Andrei Emeltchenko