Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-20 Thread Stephen Rothwell
Hi all, On Mon, 20 Jul 2020 11:50:25 -0400 Qian Cai wrote: > > On Fri, Jul 17, 2020 at 11:05:41AM -0400, Qian Cai wrote: > > On Mon, Jul 13, 2020 at 08:34:06AM -0700, syzbot wrote: > > > syzbot has bisected this bug to: > > > > > > commit d08ac70b1e0dc71ac2315007bcc3efb283b2eae4 > > > Author:

Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-20 Thread Daniel Colascione
On 7/20/20 9:00 AM, Al Viro wrote: On Mon, Jul 13, 2020 at 04:45:12PM +0800, Hillf Danton wrote: Bridge the gap between slab free and the fput in task work wrt file's private data. No. This @@ -2048,6 +2055,7 @@ SYSCALL_DEFINE1(userfaultfd, int, flags) fd =

Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-20 Thread Qian Cai
On Fri, Jul 17, 2020 at 11:05:41AM -0400, Qian Cai wrote: > On Mon, Jul 13, 2020 at 08:34:06AM -0700, syzbot wrote: > > syzbot has bisected this bug to: > > > > commit d08ac70b1e0dc71ac2315007bcc3efb283b2eae4 > > Author: Daniel Colascione > > Date: Wed Apr 1 21:39:03 2020 + > > > >

Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-20 Thread Al Viro
On Mon, Jul 13, 2020 at 04:45:12PM +0800, Hillf Danton wrote: > Bridge the gap between slab free and the fput in task work wrt > file's private data. No. This > @@ -2048,6 +2055,7 @@ SYSCALL_DEFINE1(userfaultfd, int, flags) > > fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); > if

Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-17 Thread Qian Cai
On Mon, Jul 13, 2020 at 08:34:06AM -0700, syzbot wrote: > syzbot has bisected this bug to: > > commit d08ac70b1e0dc71ac2315007bcc3efb283b2eae4 > Author: Daniel Colascione > Date: Wed Apr 1 21:39:03 2020 + > > Wire UFFD up to SELinux > > bisection log:

Re: KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-13 Thread syzbot
syzbot has bisected this bug to: commit d08ac70b1e0dc71ac2315007bcc3efb283b2eae4 Author: Daniel Colascione Date: Wed Apr 1 21:39:03 2020 + Wire UFFD up to SELinux bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14a79d1310 start commit: 89032636 Add linux-next

KASAN: use-after-free Read in userfaultfd_release (2)

2020-07-12 Thread syzbot
Hello, syzbot found the following crash on: HEAD commit:89032636 Add linux-next specific files for 20200708 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1028732f10 kernel config: https://syzkaller.appspot.com/x/.config?x=64a250ebabc6c320 dashboard