vhost/vsock: always initialize seqpacket_allow

[ Upstream commit 1e1fdcbdde ]

There are two issues around seqpacket_allow:
1. seqpacket_allow is not initialized when socket is
   created. Thus if features are never set, it will be
   read uninitialized.
2. if VIRTIO_VSOCK_F_SEQPACKET is set and then cleared,
   then seqpacket_allow will not be cleared appropriately
   (existing apps I know about don't usually do this but
    it's legal and there's no way to be sure no one relies
    on this).

To fix:
	- initialize seqpacket_allow after allocation
	- set it unconditionally in set_features

Reported-by: syzbot+6c21aeb59d0e82eb2782@syzkaller.appspotmail.com
Reported-by: Jeongjun Park <aha310510@gmail.com>
Fixes: ced7b71371 ("vhost/vsock: support SEQPACKET for transport").
Tested-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240422100010-mutt-send-email-mst@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Michael S. Tsirkin 2024-04-22 10:03:13 -04:00 committed by Greg Kroah-Hartman
parent 3750e92ccc
commit 30bd459366

View file

@ -656,6 +656,7 @@ static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
}
vsock->guest_cid = 0; /* no CID assigned yet */
vsock->seqpacket_allow = false;
atomic_set(&vsock->queued_replies, 0);
@ -799,8 +800,7 @@ static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
goto err;
}
if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET))
vsock->seqpacket_allow = true;
vsock->seqpacket_allow = features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET);
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
vq = &vsock->vqs[i];