On Thu, Apr 11, 2024 at 12:55:13PM -0700, Andrew Morton wrote: > On Wed, 10 Apr 2024 19:04:21 -0700 syzbot <syzbot+ddf4b4c0005944105a9e@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > > syzbot has found a reproducer for the following issue on: > > Thanks. > > > HEAD commit: 480e035fc4c7 Merge tag 'drm-next-2024-03-13' of https://gi.. > > git tree: upstream > > console+strace: https://syzkaller.appspot.com/x/log.txt?x=14db82bd180000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=1e5b814e91787669 > > dashboard link: https://syzkaller.appspot.com/bug?extid=ddf4b4c0005944105a9e > > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13111a4d180000 > > Seems to be userfaultfd related. > > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=156ae155180000 I can't easily trigger with the reproducer, neither did I get more information from the syzbot reproducer, and it doesn't include an UFFDIO_REGISTER. Before go reading more on syzbot itself on this specific reproducer, I'll see whether I can come up with something better than commit c2da319c2e2: I don't remember the details why I didn't do the sanity check when updating the pgtable rather than walking it. I'll give it a shot this time. Thanks, -- Peter Xu
