4.9-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 6c083c2b8a0a110cad936bc0a2c089f0d8115175 ]
Multi vsocks may setup the same cid at the same time.
Signed-off-by: Gao feng omarapazanadi@gmail.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Reviewed-by: Stefan Hajnoczi stefanha@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/vhost/vsock.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 0ec970ca64ce..6bca57896915 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -50,11 +50,10 @@ static u32 vhost_transport_get_local_cid(void) return VHOST_VSOCK_DEFAULT_HOST_CID; }
-static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) +static struct vhost_vsock *__vhost_vsock_get(u32 guest_cid) { struct vhost_vsock *vsock;
- spin_lock_bh(&vhost_vsock_lock); list_for_each_entry(vsock, &vhost_vsock_list, list) { u32 other_cid = vsock->guest_cid;
@@ -63,15 +62,24 @@ static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) continue;
if (other_cid == guest_cid) { - spin_unlock_bh(&vhost_vsock_lock); return vsock; } } - spin_unlock_bh(&vhost_vsock_lock);
return NULL; }
+static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) +{ + struct vhost_vsock *vsock; + + spin_lock_bh(&vhost_vsock_lock); + vsock = __vhost_vsock_get(guest_cid); + spin_unlock_bh(&vhost_vsock_lock); + + return vsock; +} + static void vhost_transport_do_send_pkt(struct vhost_vsock *vsock, struct vhost_virtqueue *vq) @@ -607,11 +615,12 @@ static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid) return -EINVAL;
/* Refuse if CID is already in use */ - other = vhost_vsock_get(guest_cid); - if (other && other != vsock) - return -EADDRINUSE; - spin_lock_bh(&vhost_vsock_lock); + other = __vhost_vsock_get(guest_cid); + if (other && other != vsock) { + spin_unlock_bh(&vhost_vsock_lock); + return -EADDRINUSE; + } vsock->guest_cid = guest_cid; spin_unlock_bh(&vhost_vsock_lock);