USB: gadget: zero allocate endpoint 0 buffers
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Dec 2021 18:02:15 +0000 (19:02 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 14 Dec 2021 10:32:43 +0000 (11:32 +0100)
commit 86ebbc11bb3f60908a51f3e41a17e3f477c2eaa3 upstream.

Under some conditions, USB gadget devices can show allocated buffer
contents to a host.  Fix this up by zero-allocating them so that any
extra data will all just be zeros.

Reported-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Tested-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/gadget/composite.c
drivers/usb/gadget/legacy/dbgp.c

index eda0cfe..4261329 100644 (file)
@@ -2173,7 +2173,7 @@ int composite_dev_prepare(struct usb_composite_driver *composite,
        if (!cdev->req)
                return -ENOMEM;
 
-       cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
+       cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
        if (!cdev->req->buf)
                goto fail;
 
index e567afc..355bc7d 100644 (file)
@@ -137,7 +137,7 @@ static int dbgp_enable_ep_req(struct usb_ep *ep)
                goto fail_1;
        }
 
-       req->buf = kmalloc(DBGP_REQ_LEN, GFP_KERNEL);
+       req->buf = kzalloc(DBGP_REQ_LEN, GFP_KERNEL);
        if (!req->buf) {
                err = -ENOMEM;
                stp = 2;