diff options
| author | Patrick McHardy <kaber@trash.net> | 2012-08-30 07:01:30 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-07 08:27:26 -0700 |
| commit | 0a442076e4c2cef0fd8a9b72b8f9db573e89d14f (patch) | |
| tree | 50093d67696ec0f06d8505abd7ac627223be92d9 | |
| parent | d125a7eba6bfcc5ca378ddffa37fa4805bf803df (diff) | |
IPoIB: Fix use-after-free of multicast object
commit bea1e22df494a729978e7f2c54f7bda328f74bc3 upstream.
Fix a crash in ipoib_mcast_join_task(). (with help from Or Gerlitz)
Commit c8c2afe360b7 ("IPoIB: Use rtnl lock/unlock when changing device
flags") added a call to rtnl_lock() in ipoib_mcast_join_task(), which
is run from the ipoib_workqueue, and hence the workqueue can't be
flushed from the context of ipoib_stop().
In the current code, ipoib_stop() (which doesn't flush the workqueue)
calls ipoib_mcast_dev_flush(), which goes and deletes all the
multicast entries. This takes place without any synchronization with
a possible running instance of ipoib_mcast_join_task() for the same
ipoib device, leading to a crash due to NULL pointer dereference.
Fix this by making sure that the workqueue is flushed before
ipoib_mcast_dev_flush() is called. To make that possible, we move the
RTNL-lock wrapped code to ipoib_mcast_join_finish().
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_main.c | 2 | ||||
| -rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_multicast.c | 19 |
2 files changed, 11 insertions, 10 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c index b811444dcdd4..6ea960015e0a 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c @@ -148,7 +148,7 @@ static int ipoib_stop(struct net_device *dev) netif_stop_queue(dev); - ipoib_ib_dev_down(dev, 0); + ipoib_ib_dev_down(dev, 1); ipoib_ib_dev_stop(dev, 0); if (!test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags)) { diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c index 8b6350606d57..fc045946298e 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c @@ -189,7 +189,9 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast, mcast->mcmember = *mcmember; - /* Set the cached Q_Key before we attach if it's the broadcast group */ + /* Set the multicast MTU and cached Q_Key before we attach if it's + * the broadcast group. + */ if (!memcmp(mcast->mcmember.mgid.raw, priv->dev->broadcast + 4, sizeof (union ib_gid))) { spin_lock_irq(&priv->lock); @@ -197,10 +199,17 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast, spin_unlock_irq(&priv->lock); return -EAGAIN; } + priv->mcast_mtu = IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu)); priv->qkey = be32_to_cpu(priv->broadcast->mcmember.qkey); spin_unlock_irq(&priv->lock); priv->tx_wr.wr.ud.remote_qkey = priv->qkey; set_qkey = 1; + + if (!ipoib_cm_admin_enabled(dev)) { + rtnl_lock(); + dev_set_mtu(dev, min(priv->mcast_mtu, priv->admin_mtu)); + rtnl_unlock(); + } } if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) { @@ -586,14 +595,6 @@ void ipoib_mcast_join_task(struct work_struct *work) return; } - priv->mcast_mtu = IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu)); - - if (!ipoib_cm_admin_enabled(dev)) { - rtnl_lock(); - dev_set_mtu(dev, min(priv->mcast_mtu, priv->admin_mtu)); - rtnl_unlock(); - } - ipoib_dbg_mcast(priv, "successfully joined all multicast groups\n"); clear_bit(IPOIB_MCAST_RUN, &priv->flags); |