| From 00ef7c57f894f4d4fdcacb2530600a1532b57cc6 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 19 Aug 2021 18:15:21 +0300 |
| Subject: Bluetooth: add timeout sanity check to hci_inquiry |
| |
| From: Pavel Skripkin <paskripkin@gmail.com> |
| |
| [ Upstream commit f41a4b2b5eb7872109723dab8ae1603bdd9d9ec1 ] |
| |
| Syzbot hit "task hung" bug in hci_req_sync(). The problem was in |
| unreasonable huge inquiry timeout passed from userspace. |
| Fix it by adding sanity check for timeout value to hci_inquiry(). |
| |
| Since hci_inquiry() is the only user of hci_req_sync() with user |
| controlled timeout value, it makes sense to check timeout value in |
| hci_inquiry() and don't touch hci_req_sync(). |
| |
| Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") |
| Reported-and-tested-by: syzbot+be2baed593ea56c6a84c@syzkaller.appspotmail.com |
| Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> |
| Signed-off-by: Marcel Holtmann <marcel@holtmann.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| net/bluetooth/hci_core.c | 6 ++++++ |
| 1 file changed, 6 insertions(+) |
| |
| diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c |
| index 7154af1fad81..bf1bb08b94aa 100644 |
| --- a/net/bluetooth/hci_core.c |
| +++ b/net/bluetooth/hci_core.c |
| @@ -1343,6 +1343,12 @@ int hci_inquiry(void __user *arg) |
| goto done; |
| } |
| |
| + /* Restrict maximum inquiry length to 60 seconds */ |
| + if (ir.length > 60) { |
| + err = -EINVAL; |
| + goto done; |
| + } |
| + |
| hci_dev_lock(hdev); |
| if (inquiry_cache_age(hdev) > INQUIRY_CACHE_AGE_MAX || |
| inquiry_cache_empty(hdev) || ir.flags & IREQ_CACHE_FLUSH) { |
| -- |
| 2.30.2 |
| |
