From mboxrd@z Thu Jan 1 00:00:00 1970 From: Colin King Subject: [PATCH][-next] ixgbe: don't clear_bit on xdp_ring->state if xdp_ring is null Date: Thu, 4 Oct 2018 18:57:32 +0100 Message-ID: <20181004175732.28329-1-colin.king@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Cc: kernel-janitors@vger.kernel.org To: Jeff Kirsher , "David S . Miller" , intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org Return-path: Received: from youngberry.canonical.com ([91.189.89.112]:49421 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727711AbeJEAv6 (ORCPT ); Thu, 4 Oct 2018 20:51:58 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Colin Ian King There is an earlier check to see if xdp_ring is null when configuring the tx ring, so assuming that it can still be null, the clearing of the xdp_ring->state currently could end up with a null pointer dereference. Fix this by only clearing the bit if xdp_ring is not null. Detected by CoverityScan, CID#1473795 ("Dereference after null check") Fixes: 024aa5800f32 ("ixgbe: added Rx/Tx ring disable/enable functions") Signed-off-by: Colin Ian King --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 0049a2becd7e..8e4756247324 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -10517,7 +10517,8 @@ void ixgbe_txrx_ring_enable(struct ixgbe_adapter *adapter, int ring) ixgbe_configure_rx_ring(adapter, rx_ring); clear_bit(__IXGBE_TX_DISABLED, &tx_ring->state); - clear_bit(__IXGBE_TX_DISABLED, &xdp_ring->state); + if (xdp_ring) + clear_bit(__IXGBE_TX_DISABLED, &xdp_ring->state); } /** -- 2.17.1