From: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx> commit 81c7462883b0cc0a4eeef0687f80ad5b5baee5f6 upstream. Replace hardcoded maximum USB string length (126 bytes) by definition "USB_MAX_STRING_LEN". Signed-off-by: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1592471618-29428-1-git-send-email-macpaul.lin@xxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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(-) --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1076,7 +1076,7 @@ static void collect_langs(struct usb_gad while (*sp) { s = *sp; language = cpu_to_le16(s->language); - for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) { + for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) { if (*tmp == language) goto repeat; } @@ -1151,7 +1151,7 @@ static int get_string(struct usb_composi collect_langs(sp, s->wData); } - for (len = 0; len <= 126 && s->wData[len]; len++) + for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++) continue; if (!len) return -EINVAL; --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -114,7 +114,7 @@ static int usb_string_copy(const char *s char *str; char *copy = *s_copy; ret = strlen(s); - if (ret > 126) + if (ret > USB_MAX_STRING_LEN) return -EOVERFLOW; str = kstrdup(s, GFP_KERNEL); --- a/drivers/usb/gadget/usbstring.c +++ b/drivers/usb/gadget/usbstring.c @@ -59,9 +59,9 @@ usb_gadget_get_string (struct usb_gadget return -EINVAL; /* string descriptors have length, tag, then UTF16-LE text */ - len = min ((size_t) 126, strlen (s->s)); + len = min((size_t)USB_MAX_STRING_LEN, strlen(s->s)); len = utf8s_to_utf16s(s->s, len, UTF16_LITTLE_ENDIAN, - (wchar_t *) &buf[2], 126); + (wchar_t *) &buf[2], USB_MAX_STRING_LEN); if (len < 0) return -EINVAL; buf [0] = (len + 1) * 2; --- a/include/uapi/linux/usb/ch9.h +++ b/include/uapi/linux/usb/ch9.h @@ -358,6 +358,9 @@ struct usb_config_descriptor { /*-------------------------------------------------------------------------*/ +/* USB String descriptors can contain at most 126 characters. */ +#define USB_MAX_STRING_LEN 126 + /* USB_DT_STRING: String descriptor */ struct usb_string_descriptor { __u8 bLength;