On Mon, Feb 21, 2022 at 02:59:30PM +0100, Stefano Garzarella wrote: > On Mon, Feb 21, 2022 at 12:49 PM Stefano Garzarella <sgarzare@xxxxxxxxxx> wrote: > > > > vhost_vsock_stop() calls vhost_dev_check_owner() to check the device > > ownership. It expects current->mm to be valid. > > > > vhost_vsock_stop() is also called by vhost_vsock_dev_release() when > > the user has not done close(), so when we are in do_exit(). In this > > case current->mm is invalid and we're releasing the device, so we > > should clean it anyway. > > > > Let's check the owner only when vhost_vsock_stop() is called > > by an ioctl. > > > > Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko") > > Cc: stable@xxxxxxxxxxxxxxx > > Reported-by: syzbot+1e3ea63db39f2b4440e0@xxxxxxxxxxxxxxxxxxxxxxxxx > > Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> > > --- > > drivers/vhost/vsock.c | 14 ++++++++------ > > 1 file changed, 8 insertions(+), 6 deletions(-) > > Reported-and-tested-by: syzbot+0abd373e2e50d704db87@xxxxxxxxxxxxxxxxxxxxxxxxx I don't think this patch fixes "INFO: task hung in vhost_work_dev_flush" even though syzbot says so. I am able to reproduce the issue locally even with this patch applied. Thanks, - Anirudh. > Reported-and-tested-by: syzbot+3140b17cb44a7b174008@xxxxxxxxxxxxxxxxxxxxxxxxx >