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: 324e4f85070f ("usb: gadget: uvc: allow changing interface name via configfs")
Signed-off-by: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>
---
drivers/usb/gadget/function/uvc_configfs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index e5a6b6e36b3dd8..4303a3283ba0a3 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -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); \
--
2.30.2
