From: F.A.Sulaiman Date: Tue, 24 Aug 2021 15:07:30 +0000 (+0530) Subject: HID: betop: fix slab-out-of-bounds Write in betop_probe X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6fc4476dda58f6c00097c7ddec3b772513f57525;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git HID: betop: fix slab-out-of-bounds Write in betop_probe commit 1e4ce418b1cb1a810256b5fb3fd33d22d1325993 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/hid/hid-betopff.c b/drivers/hid/hid-betopff.c index 69cfc8dc6af1..9b60efe6ec44 100644 --- a/drivers/hid/hid-betopff.c +++ b/drivers/hid/hid-betopff.c @@ -59,15 +59,22 @@ 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;