From f140ad9fe2ae16f385f8fe4dc9cf67bb4c51d794 Mon Sep 17 00:00:00 2001 From: Ciara Loftus Date: Tue, 9 Jun 2020 13:19:43 +0000 Subject: ixgbe: protect ring accesses with READ- and WRITE_ONCE READ_ONCE should be used when reading rings prior to accessing the statistics pointer. Introduce this as well as the corresponding WRITE_ONCE usage when allocating and freeing the rings, to ensure protected access. Signed-off-by: Ciara Loftus Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c | 12 ++++++------ drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 14 +++++++++++--- 2 files changed, 17 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c index fd9f5d41b594..2e35c5706cf1 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c @@ -921,7 +921,7 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter, ring->queue_index = txr_idx; /* assign ring to adapter */ - adapter->tx_ring[txr_idx] = ring; + WRITE_ONCE(adapter->tx_ring[txr_idx], ring); /* update count and index */ txr_count--; @@ -948,7 +948,7 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter, set_ring_xdp(ring); /* assign ring to adapter */ - adapter->xdp_ring[xdp_idx] = ring; + WRITE_ONCE(adapter->xdp_ring[xdp_idx], ring); /* update count and index */ xdp_count--; @@ -991,7 +991,7 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter, ring->queue_index = rxr_idx; /* assign ring to adapter */ - adapter->rx_ring[rxr_idx] = ring; + WRITE_ONCE(adapter->rx_ring[rxr_idx], ring); /* update count and index */ rxr_count--; @@ -1020,13 +1020,13 @@ static void ixgbe_free_q_vector(struct ixgbe_adapter *adapter, int v_idx) ixgbe_for_each_ring(ring, q_vector->tx) { if (ring_is_xdp(ring)) - adapter->xdp_ring[ring->queue_index] = NULL; + WRITE_ONCE(adapter->xdp_ring[ring->queue_index], NULL); else - adapter->tx_ring[ring->queue_index] = NULL; + WRITE_ONCE(adapter->tx_ring[ring->queue_index], NULL); } ixgbe_for_each_ring(ring, q_vector->rx) - adapter->rx_ring[ring->queue_index] = NULL; + WRITE_ONCE(adapter->rx_ring[ring->queue_index], NULL); adapter->q_vector[v_idx] = NULL; napi_hash_del(&q_vector->napi); diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index f162b8b8f345..97a423ecf808 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -7051,7 +7051,10 @@ void ixgbe_update_stats(struct ixgbe_adapter *adapter) } for (i = 0; i < adapter->num_rx_queues; i++) { - struct ixgbe_ring *rx_ring = adapter->rx_ring[i]; + struct ixgbe_ring *rx_ring = READ_ONCE(adapter->rx_ring[i]); + + if (!rx_ring) + continue; non_eop_descs += rx_ring->rx_stats.non_eop_descs; alloc_rx_page += rx_ring->rx_stats.alloc_rx_page; alloc_rx_page_failed += rx_ring->rx_stats.alloc_rx_page_failed; @@ -7072,15 +7075,20 @@ void ixgbe_update_stats(struct ixgbe_adapter *adapter) packets = 0; /* gather some stats to the adapter struct that are per queue */ for (i = 0; i < adapter->num_tx_queues; i++) { - struct ixgbe_ring *tx_ring = adapter->tx_ring[i]; + struct ixgbe_ring *tx_ring = READ_ONCE(adapter->tx_ring[i]); + + if (!tx_ring) + continue; restart_queue += tx_ring->tx_stats.restart_queue; tx_busy += tx_ring->tx_stats.tx_busy; bytes += tx_ring->stats.bytes; packets += tx_ring->stats.packets; } for (i = 0; i < adapter->num_xdp_queues; i++) { - struct ixgbe_ring *xdp_ring = adapter->xdp_ring[i]; + struct ixgbe_ring *xdp_ring = READ_ONCE(adapter->xdp_ring[i]); + if (!xdp_ring) + continue; restart_queue += xdp_ring->tx_stats.restart_queue; tx_busy += xdp_ring->tx_stats.tx_busy; bytes += xdp_ring->stats.bytes; -- cgit v1.2.3-59-g8ed1b