From 5cf3c2e7892ef39c95daf4849b353da56e3cf177 Mon Sep 17 00:00:00 2001 From: Anmol Karn Date: Wed, 30 Sep 2020 19:48:13 +0530 Subject: [PATCH] Bluetooth: Fix null pointer dereference in hci_event_packet() [ Upstream commit 6dfccd13db2ff2b709ef60a50163925d477549aa ] AMP_MGR is getting derefernced in hci_phy_link_complete_evt(), when called from hci_event_packet() and there is a possibility, that hcon->amp_mgr may not be found when accessing after initialization of hcon. - net/bluetooth/hci_event.c:4945 The bug seems to get triggered in this line: bredr_hcon = hcon->amp_mgr->l2cap_conn->hcon; Fix it by adding a NULL check for the hcon->amp_mgr before checking the ev-status. Fixes: d5e911928bd8 ("Bluetooth: AMP: Process Physical Link Complete evt") Reported-and-tested-by: syzbot+0bef568258653cff272f@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=0bef568258653cff272f Signed-off-by: Anmol Karn Signed-off-by: Marcel Holtmann Signed-off-by: Sasha Levin --- net/bluetooth/hci_event.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index ada778bbbec97..0a88645f103f0 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4791,6 +4791,11 @@ static void hci_phy_link_complete_evt(struct hci_dev *hdev, return; } + if (!hcon->amp_mgr) { + hci_dev_unlock(hdev); + return; + } + if (ev->status) { hci_conn_del(hcon); hci_dev_unlock(hdev);