mmc: ushc: fix NULL-deref at probe

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: stable <stable@vger.kernel.org>	# 2.6.37
Cc: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/mmc/host/ushc.c b/drivers/mmc/host/ushc.c
index d2c386f09d69..1d843357422e 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;