From: Peilin Ye <yepeilin.cs@gmail.com> stable inclusion from linux-4.19.139 commit 8c4a649c20fec015ebb326f36b47d4e39d9ff5b7 CVE: CVE-2020-36386 -------------------------------- commit 51c19bf3d5cfaa66571e4b88ba2a6f6295311101 upstream. Check upon `num_rsp` is insufficient. A malformed event packet with a large `num_rsp` number makes hci_extended_inquiry_result_evt() go out of bounds. Fix it. This patch fixes the following syzbot bug: https://syzkaller.appspot.com/bug?id=4bf11aa05c4ca51ce0df86e500fce486552dc8d... Reported-by: syzbot+d8489a79b781849b9c46@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- net/bluetooth/hci_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index b7c87f505fb6d..7eb68703783eb 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4150,7 +4150,7 @@ static void hci_extended_inquiry_result_evt(struct hci_dev *hdev, BT_DBG("%s num_rsp %d", hdev->name, num_rsp); - if (!num_rsp) + if (!num_rsp || skb->len < num_rsp * sizeof(*info) + 1) return; if (hci_dev_test_flag(hdev, HCI_PERIODIC_INQ)) -- 2.25.1