[PATCH] mmc: ushc: fix NULL-deref at probe

Johan Hovold
2017-03-13T12:40:50Z

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>
---
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 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;
--
2.12.0