USB: gadget: zero allocate endpoint 0 buffers

Origin: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit?id=6eea4ace62fa6414432692ee44f0c0a3d541d97a
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2021-39685

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>
Gbp-Pq: Topic bugfix/all
Gbp-Pq: Name USB-gadget-zero-allocate-endpoint-0-buffers.patch

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 1ef7922b57b62e3119b70e1c95a706b74ae3ad2e..284eea9f6e4d8dbfc603e7ad77a8674904bb3a3f 100644 (file)
--- 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 e567afcb2794c048044ab1a24d00a42d3db34a9f..355bc7dab9d5f623fbef3b92dd2530d2dc47e443 100644 (file)
--- 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;