From 914adb55afbc7e449512f609de19e548d1054480 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 31 Oct 2014 15:51:35 -0700 Subject: net: systemport: do not crash freeing an unitialized TX ring Callers of bcm_sysport_init_tx_ring() can currently fail, and will always call bcm_sysport_fini_tx_ring() in a loop ending at the number of TX queues (32) without checking if the TX ring was successfully initialized or not. Update bcm_sysport_fini_tx_ring() to return early and avoid a crash de-referencing ring->cbs if the TX ring was not initialized, since ring->cbs is the last part of the initialization done by bcm_sysport_init_tx_ring() that could fail. Fixes: 80105befdb4b ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver") Reported-by: Maxime Bizon Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bcmsysport.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/net/ethernet/broadcom/bcmsysport.c') diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c index c81bf74685c0..531bb7c57531 100644 --- a/drivers/net/ethernet/broadcom/bcmsysport.c +++ b/drivers/net/ethernet/broadcom/bcmsysport.c @@ -1175,6 +1175,13 @@ static void bcm_sysport_fini_tx_ring(struct bcm_sysport_priv *priv, if (!(reg & TDMA_DISABLED)) netdev_warn(priv->netdev, "TDMA not stopped!\n"); + /* ring->cbs is the last part in bcm_sysport_init_tx_ring which could + * fail, so by checking this pointer we know whether the TX ring was + * fully initialized or not. + */ + if (!ring->cbs) + return; + napi_disable(&ring->napi); netif_napi_del(&ring->napi); -- cgit v1.2.3-59-g8ed1b