[ 25/40] HID: ntrig: validate feature report details

Greg Kroah-Hartman
2013-09-25T01:26:00Z

From: Kees Cook <keescook@chromium.org>

commit 875b4e3763dbc941f15143dd1a18d10bb0be303b upstream.

A HID device could send a malicious feature report that would cause the
ntrig HID driver to trigger a NULL dereference during initialization:

[57383.031190] usb 3-1: New USB device found, idVendor=1b96, idProduct=0001
...
[57383.315193] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[57383.315308] IP: [<ffffffffa08102de>] ntrig_probe+0x25e/0x420 [hid_ntrig]

CVE-2013-2896

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rafi Rubin <rafi@seas.upenn.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/hid/hid-ntrig.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -115,7 +115,8 @@ static inline int ntrig_get_mode(struct
struct hid_report *report = hdev->report_enum[HID_FEATURE_REPORT].
report_id_hash[0x0d];

- if (!report)
+ if (!report || report->maxfield < 1 ||
+ report->field[0]->report_count < 1)
return -EINVAL;

usbhid_submit_report(hdev, report, USB_DIR_IN);