On Thu, Sep 10, 2020 at 10:04:24AM +0530, Anmol Karn wrote: > Prevent hci_phy_link_complete_evt() from dereferencing 'hcon->amp_mgr' > as NULL. Fix it by adding pointer check for it. > > Reported-and-tested-by: syzbot+0bef568258653cff272f@xxxxxxxxxxxxxxxxxxxxxxxxx > Link: https://syzkaller.appspot.com/bug?extid=0bef568258653cff272f > Signed-off-by: Anmol Karn <anmol.karan123@xxxxxxxxx> > --- > 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 4b7fc430793c..871e16804433 100644 > --- a/net/bluetooth/hci_event.c > +++ b/net/bluetooth/hci_event.c > @@ -4936,6 +4936,11 @@ static void hci_phy_link_complete_evt(struct hci_dev *hdev, > return; > } > > + if (IS_ERR_OR_NULL(hcon->amp_mgr)) { It can't be an error pointer. Shouldn't we call hci_conn_del() on this path? Try to find the Fixes tag to explain how this bug was introduced. (Don't rush to send a v2. The patch requires quite a bit more digging and detective work before it is ready). > + hci_dev_unlock(hdev); > + return; > + } > + > if (ev->status) { > hci_conn_del(hcon); > hci_dev_unlock(hdev); regards, dan carpenter