From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31487C2BA83 for ; Fri, 14 Feb 2020 18:06:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 046842187F for ; Fri, 14 Feb 2020 18:06:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581703584; bh=UsiEZwaNCOzGinm9GY9LYQeSFH9pbbl3cGztO6ANsr0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=k8ZTrjEgSE9tmGU1wpB/l0uT3osAPln+4X3m3//DqWQwJIbfFIxB7htXJwZHrvhtk fH+WCue6SbLTIYWsky8t+RgXHsrV+V829X/WEUD53MjH25hNLcjOO5f+4AQNIfiuVv aPgWXwru0HTE4XhwpXQdIateLcXJF3et8zZMAn/0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391836AbgBNSGQ (ORCPT ); Fri, 14 Feb 2020 13:06:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:35492 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731103AbgBNPy4 (ORCPT ); Fri, 14 Feb 2020 10:54:56 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C80F824673; Fri, 14 Feb 2020 15:54:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581695695; bh=UsiEZwaNCOzGinm9GY9LYQeSFH9pbbl3cGztO6ANsr0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n6JL2uVcr+8VOcuB2PA9dV57/JbWR500G8Myd7d6QAZNVfjvwU8i1/TPSIC7yjhXg Hm2HZ9XFgUGMMgT/m1CUYnleEF6VXY39/2klzzqNGtt3ba4ZeTEqOAOJAFRr4zWQMG NGxIsAuTiFZQEFgX0ujIUGn7t5Ls3691dRXFIDYk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mitch Williams , Andrew Bowers , Jeff Kirsher , Sasha Levin , intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.5 278/542] ice: add extra check for null Rx descriptor Date: Fri, 14 Feb 2020 10:44:30 -0500 Message-Id: <20200214154854.6746-278-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214154854.6746-1-sashal@kernel.org> References: <20200214154854.6746-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mitch Williams [ Upstream commit 1f45ebe0d8fbe6178670b663005f38ef8535db5d ] In the case where the hardware gives us a null Rx descriptor, it is theoretically possible that we could call one of our skb-construction functions with no data pointer, which would cause a panic. In real life, this will never happen - we only get null RX descriptors as the final descriptor in a chain of otherwise-valid descriptors. When this happens, the skb will be extant and we'll just call ice_add_rx_frag(), which can deal with empty data buffers. Unfortunately, Coverity does not have intimate knowledge of our hardware, so we must add a check here. Signed-off-by: Mitch Williams Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ice/ice_txrx.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index 2c212f64d99f2..8b2b9e254d28d 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -1071,13 +1071,16 @@ static int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget) ice_put_rx_buf(rx_ring, rx_buf); continue; construct_skb: - if (skb) + if (skb) { ice_add_rx_frag(rx_ring, rx_buf, skb, size); - else if (ice_ring_uses_build_skb(rx_ring)) - skb = ice_build_skb(rx_ring, rx_buf, &xdp); - else + } else if (likely(xdp.data)) { + if (ice_ring_uses_build_skb(rx_ring)) + skb = ice_build_skb(rx_ring, rx_buf, &xdp); + else + skb = ice_construct_skb(rx_ring, rx_buf, &xdp); + } else { skb = ice_construct_skb(rx_ring, rx_buf, &xdp); - + } /* exit if we failed to retrieve a buffer */ if (!skb) { rx_ring->rx_stats.alloc_buf_failed++; -- 2.20.1