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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 1A90FC76186 for ; Wed, 24 Jul 2019 19:53:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E43CA21873 for ; Wed, 24 Jul 2019 19:53:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563998029; bh=59DPuCb/mN6v6DZt/5oquLDKWXIFy+bD+4goqxHYoSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eGXsQ8CyIsz/LbE8Tt4A/dGeuT4NhSg5ekViwX4pp4VQxeR5QvHLNopq1zGig/hd/ VIJAZ2fJJoDELLDc/nNVT5ybnyIkINBL4pKRXEZ/F9sZPQMacb+PpeQjmidMuWcaZa WZ0VLUWAAHpW0nl1sfmlUSkARxSkCQC5OfhkcMhs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404234AbfGXTxr (ORCPT ); Wed, 24 Jul 2019 15:53:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:36316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387831AbfGXTxo (ORCPT ); Wed, 24 Jul 2019 15:53:44 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8BEAA22ADA; Wed, 24 Jul 2019 19:53:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563998024; bh=59DPuCb/mN6v6DZt/5oquLDKWXIFy+bD+4goqxHYoSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p1Au8/5SeUNUlaNNDPgTi/DGNy7AeDGobsbsH0N/E4EEiHhbjSaRetpNtMQh3rQI/ dFUSVKOolOxnkDpPJ0NVEESzW5FwSGusDauhqI4e1/Pt+aJrsNFu/eCVpd73HYyckk kvPY2WPuGdB5Ou+gSd20i3uxNQz2+Nac7zXRWV8I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Andrew Bowers , Jeff Kirsher , Sasha Levin Subject: [PATCH 5.1 221/371] iavf: fix dereference of null rx_buffer pointer Date: Wed, 24 Jul 2019 21:19:33 +0200 Message-Id: <20190724191741.178168684@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190724191724.382593077@linuxfoundation.org> References: <20190724191724.382593077@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 9fe06a51287b2d41baef7ece94df34b5abf19b90 ] A recent commit efa14c3985828d ("iavf: allow null RX descriptors") added a null pointer sanity check on rx_buffer, however, rx_buffer is being dereferenced before that check, which implies a null pointer dereference bug can potentially occur. Fix this by only dereferencing rx_buffer until after the null pointer check. Addresses-Coverity: ("Dereference before null check") Signed-off-by: Colin Ian King Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/iavf/iavf_txrx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c index 9cc2a617c9f3..2a261d849d5a 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c @@ -1296,7 +1296,7 @@ static struct sk_buff *iavf_construct_skb(struct iavf_ring *rx_ring, struct iavf_rx_buffer *rx_buffer, unsigned int size) { - void *va = page_address(rx_buffer->page) + rx_buffer->page_offset; + void *va; #if (PAGE_SIZE < 8192) unsigned int truesize = iavf_rx_pg_size(rx_ring) / 2; #else @@ -1308,6 +1308,7 @@ static struct sk_buff *iavf_construct_skb(struct iavf_ring *rx_ring, if (!rx_buffer) return NULL; /* prefetch first cache line of first page */ + va = page_address(rx_buffer->page) + rx_buffer->page_offset; prefetch(va); #if L1_CACHE_BYTES < 128 prefetch(va + L1_CACHE_BYTES); @@ -1362,7 +1363,7 @@ static struct sk_buff *iavf_build_skb(struct iavf_ring *rx_ring, struct iavf_rx_buffer *rx_buffer, unsigned int size) { - void *va = page_address(rx_buffer->page) + rx_buffer->page_offset; + void *va; #if (PAGE_SIZE < 8192) unsigned int truesize = iavf_rx_pg_size(rx_ring) / 2; #else @@ -1374,6 +1375,7 @@ static struct sk_buff *iavf_build_skb(struct iavf_ring *rx_ring, if (!rx_buffer) return NULL; /* prefetch first cache line of first page */ + va = page_address(rx_buffer->page) + rx_buffer->page_offset; prefetch(va); #if L1_CACHE_BYTES < 128 prefetch(va + L1_CACHE_BYTES); -- 2.20.1