[PATCH 3.12 091/142] mmc: ushc: fix NULL-deref at probe

[Jiri Slaby]

From: Johan Hovold <johan@xxxxxxxxxx>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

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@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 drivers/mmc/host/ushc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/ushc.c b/drivers/mmc/host/ushc.c
index c0105a2e269a..d5493a5a7e7c 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;
-- 
2.12.2