diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2013-06-06 15:20:39 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-06-11 02:46:21 -0700 |
| commit | 05c05351943cc03bf5c77e86953b24ae6fb21368 (patch) | |
| tree | 51274c86eeca2cd5040979d1fdebd81fe0518a19 | |
| parent | c2020be3c35ab230b4ee046c262ddab3e0d3aab4 (diff) | |
vhost: check owner before we overwrite ubuf_info
If device has an owner, we shouldn't touch ubuf_info
since it might be in use.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/vhost/net.c | 4 | ||||
| -rw-r--r-- | drivers/vhost/vhost.c | 8 | ||||
| -rw-r--r-- | drivers/vhost/vhost.h | 1 |
3 files changed, 12 insertions, 1 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index b07d96b8c0d1..8cf5aece8c84 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -1054,6 +1054,10 @@ static long vhost_net_set_owner(struct vhost_net *n) int r; mutex_lock(&n->dev.mutex); + if (vhost_dev_has_owner(&n->dev)) { + r = -EBUSY; + goto out; + } r = vhost_net_set_ubuf_info(n); if (r) goto out; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index beee7f5787e6..60aa5ad09a2f 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -344,13 +344,19 @@ static int vhost_attach_cgroups(struct vhost_dev *dev) } /* Caller should have device mutex */ +bool vhost_dev_has_owner(struct vhost_dev *dev) +{ + return dev->mm; +} + +/* Caller should have device mutex */ long vhost_dev_set_owner(struct vhost_dev *dev) { struct task_struct *worker; int err; /* Is there an owner already? */ - if (dev->mm) { + if (vhost_dev_has_owner(dev)) { err = -EBUSY; goto err_mm; } diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index a7ad63592987..64adcf99ff33 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -133,6 +133,7 @@ struct vhost_dev { long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs); long vhost_dev_set_owner(struct vhost_dev *dev); +bool vhost_dev_has_owner(struct vhost_dev *dev); long vhost_dev_check_owner(struct vhost_dev *); struct vhost_memory *vhost_dev_reset_owner_prepare(void); void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *); |