openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

usb: gadget: add "usb_validate_langid" function 

The USB LANGID validation code in "check_user_usb_string" function is
moved to "usb_validate_langid" function which can be used by other usb
gadget drivers.

Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
This commit is contained in:
Tao Ren 2020-03-15 12:16:28 -07:00 committed by Felipe Balbi
parent 5cc0710f23
commit 17309a6a43
3 changed files with 28 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/usb/gadget/configfs.c
View File

@ -13,8 +13,6 @@
int check_user_usb_string(const char *name,
struct usb_gadget_strings *stringtab_dev)
{
unsigned primary_lang;
unsigned sub_lang;
u16 num;
int ret;
@ -22,17 +20,7 @@ int check_user_usb_string(const char *name,
if (ret)
return ret;
primary_lang = num & 0x3ff;
sub_lang = num >> 10;
/* simple sanity check for valid langid */
switch (primary_lang) {
case 0:
case 0x62 ... 0xfe:
case 0x100 ... 0x3ff:
return -EINVAL;
}
if (!sub_lang)
if (!usb_validate_langid(num))
return -EINVAL;
stringtab_dev->language = num;

24
drivers/usb/gadget/usbstring.c
View File

@ -65,3 +65,27 @@ usb_gadget_get_string (const struct usb_gadget_strings *table, int id, u8 *buf)
return buf [0];
}
EXPORT_SYMBOL_GPL(usb_gadget_get_string);
/**
* usb_validate_langid - validate usb language identifiers
* @lang: usb language identifier
*
* Returns true for valid language identifier, otherwise false.
*/
bool usb_validate_langid(u16 langid)
{
u16 primary_lang = langid & 0x3ff; /* bit [9:0] */
u16 sub_lang = langid >> 10; /* bit [15:10] */
switch (primary_lang) {
case 0:
case 0x62 ... 0xfe:
case 0x100 ... 0x3ff:
return false;
}
if (!sub_lang)
return false;
return true;
}
EXPORT_SYMBOL_GPL(usb_validate_langid);

3
include/linux/usb/gadget.h
View File

@ -773,6 +773,9 @@ struct usb_gadget_string_container {
/* put descriptor for string with that id into buf (buflen >= 256) */
int usb_gadget_get_string(const struct usb_gadget_strings *table, int id, u8 *buf);
/* check if the given language identifier is valid */
bool usb_validate_langid(u16 langid);
/*-------------------------------------------------------------------------*/
/* utility to simplify managing config descriptors */