Commit Graph

205 Commits

Author SHA1 Message Date
Dan Carpenter
14da0230d8 Staging: Gasket: shift wrapping bug in gasket_read_modify_write_64()
This function only has one caller so mask_width is 1 and mask_shift is
32.  Shifting an int by 32 bits is undefined, but I guess on GCC it
wraps to 0x1?  Anyway it's supposed to be 0x100000000.

Fixes: 9a69f5087ccc ("drivers/staging: Gasket driver framework + Apex driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:20 -07:00
Dan Carpenter
85a2ab89f4 Staging: Gasket: fix a couple off by one bugs
The > should be >= or we end up writing one element beyond the end of
the interrupt_data->eventfd_ctxs[] array.

Fixes: 9a69f5087ccc ("drivers/staging: Gasket driver framework + Apex driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00
Dan Carpenter
c8bfb85d08 Staging: Gasket: uninitialized return in gasket_mmap()
We forgot to set the error code on this error path so ret can be
uninitialized.

Fixes: 9a69f5087ccc ("drivers/staging: Gasket driver framework + Apex driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00
Kees Cook
e1c8e7a804 drivers/staging/gasket: Use 2-factor allocator calls
As already done treewide, switch from open-coded multiplication to using
2-factor allocator helpers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00
Simon Que
0305c1f77f drivers/staging: Gasket driver framework + Apex driver
The Gasket (Google ASIC Software, Kernel Extensions, and Tools) kernel
framework is a generic, flexible system that supports thin kernel
drivers. Gasket kernel drivers are expected to handle opening and
closing devices, mmap'ing BAR space as requested, a small selection of
ioctls, and handling page table translation (covered below). Any other
functions should be handled by userspace code.

The Gasket common module is not enough to run a device. In order to
customize the Gasket code for a given piece of hardware, a device
specific module must be created. At a minimum, this module must define a
struct gasket_driver_desc containing the device-specific data for use by
the framework; in addition, the module must declare an __init function
that calls gasket_register_device with the module's gasket_driver_desc
struct. Finally, the driver must define an exit function that calls
gasket_unregister_device with the module's gasket_driver_desc struct.

One of the core assumptions of the Gasket framework is that precisely
one process is allowed to have an open write handle to the device node
at any given time. (That process may, once it has one write handle, open
any number of additional write handles.) This is accomplished by
tracking open and close data for each driver instance.

Change-Id: I0ce1dc1dc9c533026adbc3aacaefb830ecdbc3e9
Signed-off-by: Rob Springer <rspringer@google.com>
Signed-off-by: John Joseph <jnjoseph@google.com>
Signed-off-by: Simon Que <sque@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00