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 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@xxxxxxxxx> --- v1: https://lore.kernel.org/all/20230613004402.3540432-1-azeemshaikh38@xxxxxxxxx/ Changes from v1 - uses "< 0" instead of "== -E2BIG". drivers/usb/usbip/stub_main.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/usb/usbip/stub_main.c b/drivers/usb/usbip/stub_main.c index e8c3131a8543..97043b4df275 100644 --- a/drivers/usb/usbip/stub_main.c +++ b/drivers/usb/usbip/stub_main.c @@ -174,8 +174,7 @@ static ssize_t match_busid_store(struct device_driver *dev, const char *buf, return -EINVAL; /* busid needs to include \0 termination */ - len = strlcpy(busid, buf + 4, BUSID_SIZE); - if (sizeof(busid) <= len) + if (strscpy(busid, buf + 4, BUSID_SIZE) < 0) return -EINVAL; if (!strncmp(buf, "add ", 4)) { -- 2.41.0.162.gfafddb0af9-goog
