Hello Sir, > > I have looked into the Bisected logs and the problem occurs from this commit: > > > > 941992d29447 ("ethernet: amd: use IS_ENABLED() instead of checking for built-in or module") > > > > That's just the patch which made the code testable by syzbot. It didn't > introduce the bug. > > > > > Here is a diff of patch which i modified from last patch, > > > > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > > index 4b7fc430793c..6ce435064e0b 100644 > > --- a/net/bluetooth/hci_event.c > > +++ b/net/bluetooth/hci_event.c > > @@ -4936,6 +4936,12 @@ static void hci_phy_link_complete_evt(struct hci_dev *hdev, > > return; > > } > > > > + if (!hcon->amp_mgr) { > > + hci_conn_del(hcon); > > + hci_dev_unlock(hdev); > > I have no idea if calling hci_conn_del() is really the correct, thing. > I don't know the code at all. Anyway, do some research and figure out > for sure what the correct thing is. I have created my patch on the basis of the already applied conditions handling in this function, i.e whenever NULL dereference occurs, connection cleanup is required hence, hci_conn_del() is used here. Will see if anything else could be done. > > Also look for similar bugs in other places where hcon->amp_mgr is > dereferenced. For example, amp_read_loc_assoc_final_data() seems to > have a similar bug. > Sure sir will look into it. > regards, > dan carpenter > Thanks, Anmol