On Thu, Jun 18, 2020 at 05:13:38PM +0800, Macpaul Lin wrote: > Replace hardcode maximum usb string length (126 bytes) by definition > "MAX_USB_STRING_LEN". > > Signed-off-by: Macpaul Lin <[email protected]> > Acked-by: Alan Stern <[email protected]> > --- > 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
Nit, as this is part of the userspace api, we should make this "USB_MAX_STRING_LEN" as we should be using "USB_" for all exports here. That seems to be the case already except for one really odd set of "TEST_" defines, which I'll go fix up after this... I will just hand-edit this patch to make that change so you don't have to respin it again... thanks, greg k-h
