Re: [PATCH] vhost/vsock: don't check owner in vhost_vsock_stop() while releasing
From: Anirudh Rayabharam <hidden>
Date: 2022-02-21 16:16:17
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On Mon, Feb 21, 2022 at 02:59:30PM +0100, Stefano Garzarella wrote:
On Mon, Feb 21, 2022 at 12:49 PM Stefano Garzarella [off-list ref] wrote:quoted
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@vger.kernel.org Reported-by: syzbot+1e3ea63db39f2b4440e0@syzkaller.appspotmail.com Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> --- drivers/vhost/vsock.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)Reported-and-tested-by: syzbot+0abd373e2e50d704db87@syzkaller.appspotmail.com
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@syzkaller.appspotmail.com