From 9aaf4d8e2c87a5c4620085926428b5b62cf7fec8 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Thu, 9 Dec 2021 19:02:15 +0100
Subject: [PATCH] USB: gadget: zero allocate endpoint 0 buffers

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   | 2 +-
 drivers/usb/gadget/legacy/dbgp.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 1ef7922b5..284eea9f6 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -2221,7 +2221,7 @@ 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;
 
diff --git a/drivers/usb/gadget/legacy/dbgp.c b/drivers/usb/gadget/legacy/dbgp.c
index e567afcb2..355bc7dab 100644
--- a/drivers/usb/gadget/legacy/dbgp.c
+++ b/drivers/usb/gadget/legacy/dbgp.c
@@ -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;
-- 
2.54.0

