Replace hardcode maximum usb string length (126 bytes) by definition
"MAX_USB_STRING_LEN".
Signed-off-by: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
Changes for v2:
- Add definition "MAX_USB_STRING_LEN" in ch9.h instead of in usb.h.
Thanks for Alan's suggestion.
Changes for v3:
- Rebase to 5.8-rc1 and resolve conflict.
drivers/usb/gadget/composite.c | 4 ++--
drivers/usb/gadget/configfs.c | 2 +-
drivers/usb/gadget/usbstring.c | 4 ++--
include/uapi/linux/usb/ch9.h | 3 +++
4 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index cb4950c..d0de016 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1041,7 +1041,7 @@ static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
while (*sp) {
s = *sp;
language = cpu_to_le16(s->language);
- for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
+ for (tmp = buf; *tmp && tmp < &buf[MAX_USB_STRING_LEN]; tmp++) {
if (*tmp == language)
goto repeat;
}
@@ -1116,7 +1116,7 @@ static int get_string(struct usb_composite_dev *cdev,
collect_langs(sp, s->wData);
}
- for (len = 0; len <= 126 && s->wData[len]; len++)
+ for (len = 0; len <= MAX_USB_STRING_LEN && s->wData[len]; len++)
continue;
if (!len)
return -EINVAL;
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index 32b637e..70dd4ba 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -115,7 +115,7 @@ static int usb_string_copy(const char *s, char **s_copy)
char *str;
char *copy = *s_copy;
ret = strlen(s);
- if (ret > 126)
+ if (ret > MAX_USB_STRING_LEN)
return -EOVERFLOW;
str = kstrdup(s, GFP_KERNEL);
diff --git a/drivers/usb/gadget/usbstring.c b/drivers/usb/gadget/usbstring.c
index 7c24d1c..8a8d647 100644
--- a/drivers/usb/gadget/usbstring.c
+++ b/drivers/usb/gadget/usbstring.c
@@ -55,9 +55,9 @@
return -EINVAL;
/* string descriptors have length, tag, then UTF16-LE text */
- len = min ((size_t) 126, strlen (s->s));
+ len = min((size_t)MAX_USB_STRING_LEN, strlen(s->s));
len = utf8s_to_utf16s(s->s, len, UTF16_LITTLE_ENDIAN,
- (wchar_t *) &buf[2], 126);
+ (wchar_t *) &buf[2], MAX_USB_STRING_LEN);
if (len < 0)
return -EINVAL;
buf [0] = (len + 1) * 2;
diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h
index 2b623f3..cc02d05 100644
--- a/include/uapi/linux/usb/ch9.h
+++ b/include/uapi/linux/usb/ch9.h
@@ -364,6 +364,9 @@ struct usb_config_descriptor {
/*-------------------------------------------------------------------------*/
+/* USB String descriptors can contain at most 126 characters. */
+#define MAX_USB_STRING_LEN 126
+
/* USB_DT_STRING: String descriptor */
struct usb_string_descriptor {
__u8 bLength;
--
1.7.9.5
