| Message ID | 271b1e903fa359c1100caba5bfc889183af02bae.1547827336.git.2pi@mok.nu (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Darren Hart |
| Headers | show |
| Series | platform/x86: wmi: add WMI support to MODULE_DEVICE_TABLE() | expand |
On 2019-01-19, Mattias Jacobsson wrote: > In preparation for adding WMI support to MODULE_DEVICE_TABLE() move the > definition of struct wmi_device_id to mod_devicetable.h and inline > guid_string in the struct. > > Changing guid_string to an inline char array changes the loop conditions > when looping over an array of struct wmi_device_id. Therefore update > wmi_dev_match()'s loop to check for an empty guid_string instead of a > NULL pointer. > > Signed-off-by: Mattias Jacobsson <2pi@mok.nu> > --- > drivers/platform/x86/wmi.c | 2 +- > include/linux/mod_devicetable.h | 13 +++++++++++++ > include/linux/wmi.h | 5 +---- > 3 files changed, 15 insertions(+), 5 deletions(-) > > diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c > index bea35be68706..d7a2f5c8b959 100644 > --- a/drivers/platform/x86/wmi.c > +++ b/drivers/platform/x86/wmi.c > @@ -768,7 +768,7 @@ static int wmi_dev_match(struct device *dev, struct device_driver *driver) > struct wmi_block *wblock = dev_to_wblock(dev); > const struct wmi_device_id *id = wmi_driver->id_table; > > - while (id->guid_string) { > + while (id->guid_string[0] != '\0') { While looking through my patchset again I realized that I've inherited a potential null pointer dereference situation. This is relevant regardless of this patchset and I've therefore submitted a separate patch for that [1]. Further versions of this patchset will explicitly depend on [1], as this doesn't require any actual changes to this patchset, I'll wait for more comments before sending it. [1]: https://lkml.kernel.org/r/20190122200302.19861-1-2pi@mok.nu > uuid_le driver_guid; > > if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid))) > diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h > index f9bd2f34b99f..ccc9bd4f32d2 100644 > --- a/include/linux/mod_devicetable.h > +++ b/include/linux/mod_devicetable.h > @@ -779,4 +779,17 @@ struct typec_device_id { > kernel_ulong_t driver_data; > }; > > +/* WMI */ > + > +#define WMI_MODULE_PREFIX "wmi:" > +#define WMI_GUID_STRING_LEN 36 > + > +/** > + * struct wmi_device_id - WMI device identifier > + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba > + */ > +struct wmi_device_id { > + const char guid_string[WMI_GUID_STRING_LEN+1]; > +}; > + > #endif /* LINUX_MOD_DEVICETABLE_H */ > diff --git a/include/linux/wmi.h b/include/linux/wmi.h > index 4757cb5077e5..592f81afecbb 100644 > --- a/include/linux/wmi.h > +++ b/include/linux/wmi.h > @@ -18,6 +18,7 @@ > > #include <linux/device.h> > #include <linux/acpi.h> > +#include <linux/mod_devicetable.h> > #include <uapi/linux/wmi.h> > > struct wmi_device { > @@ -39,10 +40,6 @@ extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, > > extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); > > -struct wmi_device_id { > - const char *guid_string; > -}; > - > struct wmi_driver { > struct device_driver driver; > const struct wmi_device_id *id_table; > -- > 2.20.1 > Thanks, Mattias
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index bea35be68706..d7a2f5c8b959 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -768,7 +768,7 @@ static int wmi_dev_match(struct device *dev, struct device_driver *driver) struct wmi_block *wblock = dev_to_wblock(dev); const struct wmi_device_id *id = wmi_driver->id_table; - while (id->guid_string) { + while (id->guid_string[0] != '\0') { uuid_le driver_guid; if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid))) diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index f9bd2f34b99f..ccc9bd4f32d2 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -779,4 +779,17 @@ struct typec_device_id { kernel_ulong_t driver_data; }; +/* WMI */ + +#define WMI_MODULE_PREFIX "wmi:" +#define WMI_GUID_STRING_LEN 36 + +/** + * struct wmi_device_id - WMI device identifier + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + */ +struct wmi_device_id { + const char guid_string[WMI_GUID_STRING_LEN+1]; +}; + #endif /* LINUX_MOD_DEVICETABLE_H */ diff --git a/include/linux/wmi.h b/include/linux/wmi.h index 4757cb5077e5..592f81afecbb 100644 --- a/include/linux/wmi.h +++ b/include/linux/wmi.h @@ -18,6 +18,7 @@ #include <linux/device.h> #include <linux/acpi.h> +#include <linux/mod_devicetable.h> #include <uapi/linux/wmi.h> struct wmi_device { @@ -39,10 +40,6 @@ extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); -struct wmi_device_id { - const char *guid_string; -}; - struct wmi_driver { struct device_driver driver; const struct wmi_device_id *id_table;
In preparation for adding WMI support to MODULE_DEVICE_TABLE() move the definition of struct wmi_device_id to mod_devicetable.h and inline guid_string in the struct. Changing guid_string to an inline char array changes the loop conditions when looping over an array of struct wmi_device_id. Therefore update wmi_dev_match()'s loop to check for an empty guid_string instead of a NULL pointer. Signed-off-by: Mattias Jacobsson <2pi@mok.nu> --- drivers/platform/x86/wmi.c | 2 +- include/linux/mod_devicetable.h | 13 +++++++++++++ include/linux/wmi.h | 5 +---- 3 files changed, 15 insertions(+), 5 deletions(-)