From 1e4ce418b1cb1a810256b5fb3fd33d22d1325993 Mon Sep 17 00:00:00 2001 From: "F.A.Sulaiman" Date: Tue, 24 Aug 2021 20:37:30 +0530 Subject: HID: betop: fix slab-out-of-bounds Write in betop_probe Syzbot reported slab-out-of-bounds Write bug in hid-betopff driver. The problem is the driver assumes the device must have an input report but some malicious devices violate this assumption. So this patch checks hid_device's input is non empty before it's been used. Reported-by: syzbot+07efed3bc5a1407bd742@syzkaller.appspotmail.com Signed-off-by: F.A. SULAIMAN Reviewed-by: Pavel Skripkin Signed-off-by: Jiri Kosina --- drivers/hid/hid-betopff.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'drivers/hid') diff --git a/drivers/hid/hid-betopff.c b/drivers/hid/hid-betopff.c index 0790fbd3fc9a..467d789f9bc2 100644 --- a/drivers/hid/hid-betopff.c +++ b/drivers/hid/hid-betopff.c @@ -56,15 +56,22 @@ static int betopff_init(struct hid_device *hid) { struct betopff_device *betopff; struct hid_report *report; - struct hid_input *hidinput = - list_first_entry(&hid->inputs, struct hid_input, list); + struct hid_input *hidinput; struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list; - struct input_dev *dev = hidinput->input; + struct input_dev *dev; int field_count = 0; int error; int i, j; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + + hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + dev = hidinput->input; + if (list_empty(report_list)) { hid_err(hid, "no output reports found\n"); return -ENODEV; -- cgit