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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB1D3C433EF for ; Fri, 1 Apr 2022 17:09:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349580AbiDARLW (ORCPT ); Fri, 1 Apr 2022 13:11:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239345AbiDARLT (ORCPT ); Fri, 1 Apr 2022 13:11:19 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDC912A248; Fri, 1 Apr 2022 10:09:29 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id s72so2872381pgc.5; Fri, 01 Apr 2022 10:09:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=LImEOxfyIPGlQbCQpplXE60DtSoSNNxE1+4gEbrz2CE=; b=cs2hIo1S07860WC/5XZ0dR/RsivlP0TwpIQKBXM2BF8Q+Dfl2P62mdz0Ota8I+e9AP JaTwdeyGd/rvilDz/t2qLn4yYUmSb5kZFnt70yVrxS/cCFYlKiCL2QZAu3bVnPHkEEd4 vfKQ+Mns7K7AtAH8C6d74FxAYWIA9qp2I+snEEzOaHu5tXrHHrlEU2sowSJXA1Uq6thQ toNlRAqYsmtX8ruR4IpP1hHYcKw182FKOz6dKZhFjU81ZFIABp7DCZfeOh5z0hpQXa/X eKzvrHqo5I0KPIbJ5w8XhnVTp0HC87h2oujurqPx4O8fpKE+lSs+mtKhz7591GEkRgUQ xOTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=LImEOxfyIPGlQbCQpplXE60DtSoSNNxE1+4gEbrz2CE=; b=ItFGK/8gE+7xat4friLhBKvUHG6J2I3hH6gGk37325MewvMsIhbqIDpGBw4xuAvhem q/rcBqHGZOEhVK7xmlzQHWi1nT2CeKCXYrXrRei7QSFEiDO+jeeNp6Hs0sJt+TSGLdzL t5VMMl17czvT/ED377OP2B7a7RAx4AkYtPCR/HNbgkEzqGsUeswC4KVNQjdpm66nX8Re YtPpHv5HVnWxMY/e29QQ2zxaQW9G65bY+t5t1TrNx18mQwA/o2oGpadrRYVvkdC4q8TH VCHrv9jvugGZ7GHDU5Qg3J8jyMJVQeUz5XUONdH+7nqZbRrncIalzMzKmAREg4jBUigs rf4A== X-Gm-Message-State: AOAM531FYL66bGdUbxhFscIsOTUkp0u+CnxJ2GMlnZ5RkNn9WsZamb/c cEdHozseweAW59OEEH3smOQ= X-Google-Smtp-Source: ABdhPJyTguw1YFMZTCc6C259mXYcn/eEEQuG6PzA3/XrlZClxztaNrfrUxhFbqJ1CDk7VdLpq8x+GA== X-Received: by 2002:a62:840b:0:b0:4fa:31ae:7739 with SMTP id k11-20020a62840b000000b004fa31ae7739mr11730077pfd.6.1648832969146; Fri, 01 Apr 2022 10:09:29 -0700 (PDT) Received: from [192.168.86.235] (c-73-241-150-58.hsd1.ca.comcast.net. [73.241.150.58]) by smtp.gmail.com with ESMTPSA id bt18-20020a056a00439200b004faad3ae59esm3581968pfb.95.2022.04.01.10.09.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 01 Apr 2022 10:09:28 -0700 (PDT) Message-ID: <5d9fed4f-ff87-cb14-3c7d-8899cb3e4370@gmail.com> Date: Fri, 1 Apr 2022 10:09:26 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.2 Subject: Re: [PATCH] net/ipv4: fix potential NULL dereference in sisfb_post_sis300() Content-Language: en-US To: Haowen Bai , "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1648785432-21824-1-git-send-email-baihaowen@meizu.com> From: Eric Dumazet In-Reply-To: <1648785432-21824-1-git-send-email-baihaowen@meizu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/31/22 20:57, Haowen Bai wrote: > psin and psl could be null without checking null and return, so > we need to dereference after checking. > > Signed-off-by: Haowen Bai > --- > net/ipv4/igmp.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c > index 2ad3c7b..d400080 100644 > --- a/net/ipv4/igmp.c > +++ b/net/ipv4/igmp.c > @@ -2569,7 +2569,7 @@ int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, > copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) { > return -EFAULT; > } > - if (len && > + if (len && psl && len can not be !0 here if len was 0 psl = rtnl_dereference(pmc->sflist); if (!psl) {    count = 0; ->len == 0 > copy_to_user(&optval->imsf_slist_flex[0], psl->sl_addr, len)) > return -EFAULT; > return 0; > @@ -2608,7 +2608,7 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, > count = psl ? psl->sl_count : 0; > copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; > gsf->gf_numsrc = count; > - for (i = 0; i < copycount; i++, p++) { > + for (i = 0; i < copycount && psin && psl; i++, p++) { > struct sockaddr_storage ss; > > psin = (struct sockaddr_in *)&ss; Same here.