| Message ID | 20230613004341.3540325-1-azeemshaikh38@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | usb: gadget: function: printer: Replace strlcpy with strscpy | expand |
diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c index 28db3e336e7d..10dc7c55c25f 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 == -E2BIG) { result = PAGE_SIZE; } else if (page[result - 1] != '\n' && result + 1 < PAGE_SIZE) { page[result++] = '\n';
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 -E2BIG is used to check for truncation instead of sizeof(dest). [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 <azeemshaikh38@gmail.com> --- drivers/usb/gadget/function/f_printer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)