From ee400a1be11527e1ea58b716b338b9fb6665b8d6 Mon Sep 17 00:00:00 2001 From: Azeem Shaikh Date: Thu, 15 Jun 2023 18:03:18 +0000 Subject: usb: gadget: function: printer: Replace strlcpy with strscpy strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). Direct replacement is safe here since return value of -errno is used to check for truncation instead of PAGE_SIZE. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh Link: https://lore.kernel.org/r/20230615180318.400639-1-azeemshaikh38@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_printer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c index 28db3e336e7d..b91425611969 100644 --- a/drivers/usb/gadget/function/f_printer.c +++ b/drivers/usb/gadget/function/f_printer.c @@ -1211,8 +1211,8 @@ static ssize_t f_printer_opts_pnp_string_show(struct config_item *item, if (!opts->pnp_string) goto unlock; - result = strlcpy(page, opts->pnp_string, PAGE_SIZE); - if (result >= PAGE_SIZE) { + result = strscpy(page, opts->pnp_string, PAGE_SIZE); + if (result < 1) { result = PAGE_SIZE; } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) { page[result++] = '\n'; -- cgit v1.2.3