[ Upstream commit eba9ac7abab91c8f6d351460239108bef5e7a0b6 ]
Since commit fa1f68db6ca7 ("drivers: misc: pass miscdevice pointer via
file private data"), the miscdevice stores a pointer to itself inside
filp->private_data, which means that private_data will not be NULL when
wmi_char_open() is called. This might cause memory corruption should
wmi_char_open() be unable to find its driver, something which can
happen when the associated WMI device is deleted in wmi_free_devices().
Fix the problem by using the miscdevice pointer to retrieve the WMI
device data associated with a char device using container_of(). This
also avoids wmi_char_open() picking a wrong WMI device bound to a
driver with the same name as the original driver.
Fixes: 44b6b7661132 ("platform/x86: wmi: create userspace interface for drivers")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231020211005.38216-5-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 43aacf838ef7384d985ef5385ecb0124f8c70007 ]
Some pointers are initialized when they are defined,
but they are almost immediately reassigned in the
following lines. Remove these superfluous assignments.
Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210904175450.156801-6-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Stable-dep-of: eba9ac7abab9 ("platform/x86: wmi: Fix opening of char device")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ed85891a276edaf7a867de0e9acd0837bc3008f2 ]
When a WMI device besides the first one somehow fails to register,
retval is returned while still containing a negative error code. This
causes the ACPI device fail to probe, leaving behind zombie WMI devices
leading to various errors later.
Handle the single error path separately and return 0 unconditionally
after trying to register all WMI devices to solve the issue. Also
continue to register WMI devices even if some fail to allocate memory.
Fixes: 6ee50aaa9a20 ("platform/x86: wmi: Instantiate all devices before adding them")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231020211005.38216-4-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
