From: Johan Hovold <johan@kernel.org>
Date: Mon, 13 Mar 2017 12:40:22 +0000 (+0100)
Subject: mmc: ushc: fix NULL-deref at probe
X-Git-Tag: v3.12.73~51
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1bdb8d57fe35e67e9b1b47adeedcbb370c758823;p=thirdparty%2Fkernel%2Fstable.git

mmc: ushc: fix NULL-deref at probe

commit 181302dc7239add8ab1449c23ecab193f52ee6ab upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: 53f3a9e26ed5 ("mmc: USB SD Host Controller (USHC) driver")
Cc: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---

diff --git a/drivers/mmc/host/ushc.c b/drivers/mmc/host/ushc.c
index c0105a2e269a7..d5493a5a7e7cc 100644
--- a/drivers/mmc/host/ushc.c
+++ b/drivers/mmc/host/ushc.c
@@ -426,6 +426,9 @@ static int ushc_probe(struct usb_interface *intf, const struct usb_device_id *id
 	struct ushc_data *ushc;
 	int ret;
 
+	if (intf->cur_altsetting->desc.bNumEndpoints < 1)
+		return -ENODEV;
+
 	mmc = mmc_alloc_host(sizeof(struct ushc_data), &intf->dev);
 	if (mmc == NULL)
 		return -ENOMEM;