usbip: tools: fix GCC8 warning for strncpy

GCC8 started emitting warning about using strncpy with number of bytes
exactly equal destination size which could lead to non-zero terminated
string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1"
as number of bytes to ensure name is always zero-terminated.

Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190725132209.GA27590@jerryopenix
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
index bb424638d75b0e639020a765192bea2020dd369c..b8d7d480595a8477db79c090cd46ee2f671a4e56 100644 (file)
--- a/tools/usb/usbip/libsrc/usbip_common.c
+++ b/tools/usb/usbip/libsrc/usbip_common.c
@@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
        path = udev_device_get_syspath(sdev);
        name = udev_device_get_sysname(sdev);
 
-       strncpy(udev->path,  path,  SYSFS_PATH_MAX);
-       strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
+       strncpy(udev->path,  path,  SYSFS_PATH_MAX - 1);
+       udev->path[SYSFS_PATH_MAX - 1] = '\0';
+       strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1);
+       udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
 
        sscanf(name, "%u-%u", &busnum, &devnum);
        udev->busnum = busnum;

diff --git a/tools/usb/usbip/libsrc/usbip_device_driver.c b/tools/usb/usbip/libsrc/usbip_device_driver.c
index 5a3726eb44abcd54b3d55e5f452ab73bc96ca015..051d7d3f443b4f6663d38b5c190f9293ac51f359 100644 (file)
--- a/tools/usb/usbip/libsrc/usbip_device_driver.c
+++ b/tools/usb/usbip/libsrc/usbip_device_driver.c
@@ -91,7 +91,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
        copy_descr_attr16(dev, &descr, idProduct);
        copy_descr_attr16(dev, &descr, bcdDevice);
 
-       strncpy(dev->path, path, SYSFS_PATH_MAX);
+       strncpy(dev->path, path, SYSFS_PATH_MAX - 1);
+       dev->path[SYSFS_PATH_MAX - 1] = '\0';
 
        dev->speed = USB_SPEED_UNKNOWN;
        speed = udev_device_get_sysattr_value(sdev, "current_speed");
@@ -110,7 +111,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
        dev->busnum = 0;
 
        name = udev_device_get_sysname(plat);
-       strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE);
+       strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE - 1);
+       dev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
        return 0;
 err:
        fclose(fd);