wusb: Fix potential memory leak in wusb_dev_sec_add()

Do not leak memory by updating pointer with potentially NULL realloc return value.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/wusbcore/security.c b/drivers/usb/wusbcore/security.c
index fa810a83e8300957c72de584ab3f3fcd1e31a29a..dd88441c8f7891e0d242e1107d6ff585a30999e4 100644 (file)
--- a/drivers/usb/wusbcore/security.c
+++ b/drivers/usb/wusbcore/security.c
@@ -202,7 +202,7 @@ int wusb_dev_sec_add(struct wusbhc *wusbhc,
 {
        int result, bytes, secd_size;
        struct device *dev = &usb_dev->dev;
-       struct usb_security_descriptor *secd;
+       struct usb_security_descriptor *secd, *new_secd;
        const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
        const void *itr, *top;
        char buf[64];
@@ -221,11 +221,12 @@ int wusb_dev_sec_add(struct wusbhc *wusbhc,
                goto out;
        }
        secd_size = le16_to_cpu(secd->wTotalLength);
-       secd = krealloc(secd, secd_size, GFP_KERNEL);
-       if (secd == NULL) {
+       new_secd = krealloc(secd, secd_size, GFP_KERNEL);
+       if (new_secd == NULL) {
                dev_err(dev, "Can't allocate space for security descriptors\n");
                goto out;
        }
+       secd = new_secd;
        result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
                                    0, secd, secd_size);
        if (result < secd_size) {