On Mon, Aug 10, 2020 at 8:31 PM Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> wrote: > > On Mon, Aug 10, 2020 at 08:37:18AM -0700, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: fffe3ae0 Merge tag 'for-linus-hmm' of git://git.kernel.org.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=12f34d3a900000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=50463ec6729f9706 > > dashboard link: https://syzkaller.appspot.com/bug?extid=8f2165a7b1f2820feffc > > compiler: gcc (GCC) 10.1.0-syz 20200507 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1517701c900000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11b7e0e2900000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+8f2165a7b1f2820feffc@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > general protection fault, probably for non-canonical address 0xdffffc000000004c: 0000 [#1] PREEMPT SMP KASAN > > KASAN: null-ptr-deref in range [0x0000000000000260-0x0000000000000267] > > CPU: 0 PID: 12765 Comm: syz-executor391 Not tainted 5.8.0-syzkaller #0 > > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > > RIP: 0010:sctp_ulpevent_notify_peer_addr_change+0xa9/0xad0 net/sctp/ulpevent.c:346 > > Crashed in code added by 45ebf73ebcec ("sctp: check assoc before > SCTP_ADDR_{MADE_PRIM, ADDED} event"), but it would have crashed a > couple of instructions later on already anyway. > > I can't reproduce this crash, with the same commit and kernel config. > I'm not seeing how transport->asoc can be null at there. > I haven't been able to reproduce this yet either. Doesn't this report have similarities with "general protection fault in sctp_ulpevent_nofity_peer_addr_change" from 19 March 2020? https://syzkaller.appspot.com/bug?extid=3950016bd95c2ca0377b