usb: gadget: uvc: fix changing interface name via configfs

When setting the function name, it is always truncated by one char since
snprintf is always including the null-termination in the len parameter.
We use strscpy and fix the size setting to use len + 1 instead.

Fixes: 324e4f8507 ("usb: gadget: uvc: allow changing interface name via configfs")
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20220707115612.2760569-1-m.grzeschik@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michael Grzeschik 2022-07-07 13:56:12 +02:00 committed by Greg Kroah-Hartman
parent 6fb9e1d947
commit 3d0dc53902

View file

@ -2371,6 +2371,7 @@ static ssize_t f_uvc_opts_string_##cname##_store(struct config_item *item,\
const char *page, size_t len) \
{ \
struct f_uvc_opts *opts = to_f_uvc_opts(item); \
int size = min(sizeof(opts->aname), len + 1); \
int ret = 0; \
\
mutex_lock(&opts->lock); \
@ -2379,8 +2380,9 @@ static ssize_t f_uvc_opts_string_##cname##_store(struct config_item *item,\
goto end; \
} \
\
ret = snprintf(opts->aname, min(sizeof(opts->aname), len), \
"%s", page); \
ret = strscpy(opts->aname, page, size); \
if (ret == -E2BIG) \
ret = size - 1; \
\
end: \
mutex_unlock(&opts->lock); \