From 8e6330df96c405fe442d86f5dd5c2791c53a71e1 Mon Sep 17 00:00:00 2001 From: Anmol Karn Date: Thu, 7 Jan 2021 07:37:43 +0000 Subject: [PATCH] Bluetooth: Fix null pointer dereference in hci_event_packet() stable inclusion from stable-5.10.4 commit 147cdf5f344b8432f103bc154eb250f848c54767 bugzilla: 46903 -------------------------------- [ 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 Signed-off-by: Chen Jun Acked-by: Xie XiuQi --- 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 cbdf2a555975..17a72695865b 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4941,6 +4941,11 @@ 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); -- GitLab