kernel/linux.git/include/net/bluetooth/rfcomm.h, branch v6.6.132

Bluetooth: Replace zero-length array with flexible-array member

2020-02-28T07:30:02+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Marcel Holtmann

Bluetooth: RFCOMM: Use MTU auto tune logic

2020-02-19T19:31:45+00:00

This reuse the L2CAP MTU auto logic to select the MTU used for RFCOMM channels, this should increase the maximum from 1013 to 1021 when 3-DH5 is supported. Since it does not set an L2CAP MTU we no longer need a debugfs so that is removed. Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Marcel Holtmann

Bluetooth: convert rfcomm_dlc.refcnt from atomic_t to refcount_t

2017-04-12T20:02:36+00:00

refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: Marcel Holtmann

Bluetooth: Remove duplicate constant for RFCOMM PSM

2014-12-20T17:55:04+00:00

The RFCOMM_PSM constant is actually a duplicate. So remove it and use the L2CAP_PSM_RFCOMM constant instead. Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg

Bluetooth: Convert RFCOMM spinlocks into mutexes

2014-05-06T02:25:06+00:00

Enabling CONFIG_DEBUG_ATOMIC_SLEEP has shown that some rfcomm functions acquiring spinlocks call sleeping locks further in the chain. Converting the offending spinlocks into mutexes makes sleeping safe. Signed-off-by: Libor Pechacek Signed-off-by: Marcel Holtmann

Bluetooth: Don't fail RFCOMM tty writes

2014-02-14T21:39:32+00:00

The tty driver api design prefers no-fail writes if the driver write_room() method has previously indicated space is available to accept writes. Since this is trivially possible for the RFCOMM tty driver, do so. Introduce rfcomm_dlc_send_noerror(), which queues but does not schedule the krfcomm thread if the dlc is not yet connected (and thus does not error based on the connection state). The mtu size test is also unnecessary since the caller already chunks the written data into mtu size. Signed-off-by: Peter Hurley Tested-By: Alexander Holler Signed-off-by: Marcel Holtmann

Bluetooth: Verify dlci not in use before rfcomm_dev create

2014-02-14T21:39:30+00:00

Only one session/channel combination may be in use at any one time. However, the failure does not occur until the tty is opened (in rfcomm_dlc_open()). Because these settings are actually bound at rfcomm device creation (via RFCOMMCREATEDEV ioctl), validate and fail before creating the rfcomm tty device. Signed-off-by: Peter Hurley Tested-By: Alexander Holler Signed-off-by: Marcel Holtmann

Bluetooth: Fix unreleased rfcomm_dev reference

2014-02-14T21:39:29+00:00

When RFCOMM_RELEASE_ONHUP is set, the rfcomm tty driver 'takes over' the initial rfcomm_dev reference created by the RFCOMMCREATEDEV ioctl. The assumption is that the rfcomm tty driver will release the rfcomm_dev reference when the tty is freed (in rfcomm_tty_cleanup()). However, if the tty is never opened, the 'take over' never occurs, so when RFCOMMRELEASEDEV ioctl is called, the reference is not released. Track the state of the reference 'take over' so that the release is guaranteed by either the RFCOMMRELEASEDEV ioctl or the rfcomm tty driver. Note that the synchronous hangup in rfcomm_release_dev() ensures that rfcomm_tty_install() cannot race with the RFCOMMRELEASEDEV ioctl. Signed-off-by: Peter Hurley Tested-By: Alexander Holler Signed-off-by: Marcel Holtmann

Bluetooth: Release rfcomm_dev only once

2014-02-14T21:39:29+00:00

No logic prevents an rfcomm_dev from being released multiple times. For example, if the rfcomm_dev ref count is large due to pending tx, then multiple RFCOMMRELEASEDEV ioctls may mistakenly release the rfcomm_dev too many times. Note that concurrent ioctls are not required to create this condition. Introduce RFCOMM_DEV_RELEASED status bit which guarantees the rfcomm_dev can only be released once. NB: Since the flags are exported to userspace, introduce the status field to track state for which userspace should not be aware. Signed-off-by: Peter Hurley Tested-By: Alexander Holler Signed-off-by: Marcel Holtmann

Bluetooth: Handle security level 4 for RFCOMM connections

2014-02-13T07:51:35+00:00

With the introduction of security level 4, the RFCOMM sockets need to be made aware of this new level. This change ensures that the pairing requirements are set correctly for these connections. Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg