Awesome, thanks Claudio. As you predicted this nailed these 4 repros with a single patch :) Reported-by: syzbot+2cd350dfe5c96f646...@syzkaller.appspotmail.com Reported-by: syzbot+139ac2d7d3d601623...@syzkaller.appspotmail.com Reported-by: syzbot+02168317bd0156c13...@syzkaller.appspotmail.com Reported-by: syzbot+de8d2459ecf4cdc57...@syzkaller.appspotmail.com
On Sun, Dec 2, 2018 at 2:15 AM Claudio Jeker <cje...@diehard.n-r-g.com> wrote: > On Sun, Dec 02, 2018 at 09:29:23AM +0100, Claudio Jeker wrote: > > On Sat, Dec 01, 2018 at 06:44:31PM -0800, Greg Steuck wrote: > > > This thwarts the reproducer. Again, I don't know if the invariants are > > > getting violated somewhere else and the patch below is simply papering > over > > > the symptoms. > > > > I would like to better understand how we get so far with a socket where > > so_pcb is not initiallized. This and also the other bug are baisically > the > > same. The stack assumes that after a successful socket() operation both > > socket and pcb exist and are a connected. Since this seems to not be > > the case it is important to catch those errors further up in > uipc_socket.c > > before passing down into protocol specific functions. > > > > So the issue is the double connect() call on the SOCk_RAW socket. > The second connect is calling PRU_DISCONNECT which in the end does a > FALLTHROUGH into PRU_ABORT which removes the inp by calling > in_pcbdetach(). > > I think the proper fix is to not have this FALLTHROUGH and just call > soisdisconnected(). Maybe inp->inp_faddr should also be reset to 0. > > This will fix also other double connect() SOCk_RAW crashes you spotted. > -- > :wq Claudio > > Index: raw_ip.c > =================================================================== > RCS file: /cvs/src/sys/netinet/raw_ip.c,v > retrieving revision 1.115 > diff -u -p -r1.115 raw_ip.c > --- raw_ip.c 10 Nov 2018 18:40:34 -0000 1.115 > +++ raw_ip.c 2 Dec 2018 09:52:58 -0000 > @@ -385,7 +385,8 @@ rip_usrreq(struct socket *so, int req, s > error = ENOTCONN; > break; > } > - /* FALLTHROUGH */ > + soisdisconnected(so); > + break; > case PRU_ABORT: > soisdisconnected(so); > if (inp == NULL) > -- nest.cx is Gmail hosted, use PGP for anything private. Key: http://goo.gl/6dMsr Fingerprint: 5E2B 2D0E 1E03 2046 BEC3 4D50 0B15 42BD 8DF5 A1B0