From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.9 20/33] HID: holtek: test for sanity of intfdata Date: Tue, 13 Aug 2019 22:23:10 -0400 Message-ID: <20190814022323.17111-20-sashal@kernel.org> References: <20190814022323.17111-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190814022323.17111-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Oliver Neukum , syzbot+965152643a75a56737be@syzkaller.appspotmail.com, Jiri Kosina , Sasha Levin , linux-input@vger.kernel.org List-Id: linux-input@vger.kernel.org From: Oliver Neukum [ Upstream commit 01ec0a5f19c8c82960a07f6c7410fc9e01d7fb51 ] The ioctl handler uses the intfdata of a second interface, which may not be present in a broken or malicious device, hence the intfdata needs to be checked for NULL. [jkosina@suse.cz: fix newly added spurious space] Reported-by: syzbot+965152643a75a56737be@syzkaller.appspotmail.com Signed-off-by: Oliver Neukum Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/hid-holtek-kbd.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-holtek-kbd.c b/drivers/hid/hid-holtek-kbd.c index 6e1a4a4fc0c10..ab9da597106fa 100644 --- a/drivers/hid/hid-holtek-kbd.c +++ b/drivers/hid/hid-holtek-kbd.c @@ -126,9 +126,14 @@ static int holtek_kbd_input_event(struct input_dev *dev, unsigned int type, /* Locate the boot interface, to receive the LED change events */ struct usb_interface *boot_interface = usb_ifnum_to_if(usb_dev, 0); + struct hid_device *boot_hid; + struct hid_input *boot_hid_input; - struct hid_device *boot_hid = usb_get_intfdata(boot_interface); - struct hid_input *boot_hid_input = list_first_entry(&boot_hid->inputs, + if (unlikely(boot_interface == NULL)) + return -ENODEV; + + boot_hid = usb_get_intfdata(boot_interface); + boot_hid_input = list_first_entry(&boot_hid->inputs, struct hid_input, list); return boot_hid_input->input->event(boot_hid_input->input, type, code, -- 2.20.1