From 07ac3e7099b5788ee4b78233c96532c6209a304b Mon Sep 17 00:00:00 2001 From: David L Stevens Date: Mon, 26 Jan 2015 15:54:35 -0500 Subject: [PATCH] sunvnet: free pending tx buffers before clearing ring data This patch moves the clearing of ring data in vnet_port_free_tx_bufs to after the freeing of pending buffers in the ring. Otherwise, this can result in dereferencing a NULL pointer. Reported-by: Sowmini Varadhan Signed-off-by: David L Stevens Signed-off-by: David S. Miller --- drivers/net/ethernet/sun/sunvnet.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c index b5a1d3d7b0bf..fe044f31708e 100644 --- a/drivers/net/ethernet/sun/sunvnet.c +++ b/drivers/net/ethernet/sun/sunvnet.c @@ -1637,16 +1637,9 @@ static void vnet_port_free_tx_bufs(struct vnet_port *port) int i; dr = &port->vio.drings[VIO_DRIVER_TX_RING]; - if (dr->base) { - ldc_free_exp_dring(port->vio.lp, dr->base, - (dr->entry_size * dr->num_entries), - dr->cookies, dr->ncookies); - dr->base = NULL; - dr->entry_size = 0; - dr->num_entries = 0; - dr->pending = 0; - dr->ncookies = 0; - } + + if (dr->base == NULL) + return; for (i = 0; i < VNET_TX_RING_SIZE; i++) { struct vio_net_desc *d; @@ -1666,6 +1659,14 @@ static void vnet_port_free_tx_bufs(struct vnet_port *port) port->tx_bufs[i].skb = NULL; d->hdr.state = VIO_DESC_FREE; } + ldc_free_exp_dring(port->vio.lp, dr->base, + (dr->entry_size * dr->num_entries), + dr->cookies, dr->ncookies); + dr->base = NULL; + dr->entry_size = 0; + dr->num_entries = 0; + dr->pending = 0; + dr->ncookies = 0; } static int vnet_port_alloc_tx_ring(struct vnet_port *port) -- 2.20.1