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 6120DC433FE for ; Wed, 2 Nov 2022 10:52:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230171AbiKBKwD (ORCPT ); Wed, 2 Nov 2022 06:52:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40022 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230199AbiKBKwA (ORCPT ); Wed, 2 Nov 2022 06:52:00 -0400 Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6FA321E2A for ; Wed, 2 Nov 2022 03:51:59 -0700 (PDT) Received: by mail-wm1-x32e.google.com with SMTP id f16-20020a05600c491000b003cf66a2e7c0so982748wmp.5 for ; Wed, 02 Nov 2022 03:51:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isovalent-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=X3t89BApMC9GV5pVw6Uj+C2lxdZ+0mjrFrpyj0nVCJ0=; b=RoStPn3f7qNAjvTlBT5i0I+o3K99wdi9ACnHtuu3av0GiNmY4mcgzTnVJqyfMYeYfK ZX8Yx0MNU24vwcb2srYLsOIynFFGxbuHs8/u3lXUWSV9ZZF+q5BzjziXt7svqTA74XPj fPV5U3P284lsqBrZh6SaPmA6Z2P5UsydrE9FBMuxe2CrXpT5EnECWBM+EsgNWkl8GHlJ SJQT+TL9nrT7t60ImXuyEnulYHAqJh6YTP8cqlGZZGDYt+s2fSFZZ23wsJkArQccM3bK hA+lffNiVZ+w8/woU60YXfgDMn1i7pjGQNlVn/wMoImgZhdOZ59e56c/5YIhJOoPRtP4 qI5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=X3t89BApMC9GV5pVw6Uj+C2lxdZ+0mjrFrpyj0nVCJ0=; b=yfhFQIUa5CaAchCGEj7s1ocyiqA0Vl85Lv5eF5jsi3eyg/rc/fZOwZANO7EBqXmGFB 8AO49vw1m9LP0MahQcYiYmwvdkVwe32JuKbFmZVwM+7+bXv5mhy8xCjMOI9fTHJaHJHZ gUxdSVHl3CmnJobrwR7qyVe6UtJuRekMF6iejuqAJ+1ImkHP+89zvWW3PAae4Ir7LXOy O6EA+GV90JimX1YJedsRdysRHjpmvopKKbSi2eDKqMRBH6R//nHQWYXe3KZebEy5oUj6 BPLhDhuCqeDqbjPeI5ND9m57Qb1+Nhk+88dz5OWjQ55htM6hapCzgbimkHEcszvwyto+ q9Ww== X-Gm-Message-State: ACrzQf0EXP7YvRpm9CQ9/nx2CA41lQynXL2yV83PGdY22ay8KT2doYJb Sw663ZqJCnZQGiOL0stnQyyZyQ== X-Google-Smtp-Source: AMsMyM5BM7WyTIpyAwNqmgJuMpcJ9L39yP3gmgFPQqONbA9X+8z7GKjHpV7nkv21MwfpIaJWjP0Otg== X-Received: by 2002:a05:600c:198e:b0:3c6:e7e6:490 with SMTP id t14-20020a05600c198e00b003c6e7e60490mr15296534wmq.79.1667386318373; Wed, 02 Nov 2022 03:51:58 -0700 (PDT) Received: from [192.168.178.32] ([51.155.200.13]) by smtp.gmail.com with ESMTPSA id h19-20020a05600c351300b003b4ff30e566sm1898157wmq.3.2022.11.02.03.51.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Nov 2022 03:51:57 -0700 (PDT) Message-ID: Date: Wed, 2 Nov 2022 10:51:56 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.1 Subject: Re: [PATCH bpf] bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE Content-Language: en-GB To: Pu Lehui , bpf@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Pu Lehui References: <20221102084034.3342995-1-pulehui@huaweicloud.com> From: Quentin Monnet In-Reply-To: <20221102084034.3342995-1-pulehui@huaweicloud.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2022-11-02 16:40 UTC+0800 ~ Pu Lehui > From: Pu Lehui > > When using bpftool to pin {PROG, MAP, LINK} without FILE, > segmentation fault will occur. The reson is that the lack > of FILE will cause strlen to trigger NULL pointer dereference. > The corresponding stacktrace is shown below: > > do_pin > do_pin_any > do_pin_fd > mount_bpffs_for_pin > strlen(name) <- NULL pointer dereference > > Fix it by adding validation to the common process. > > Fixes: 75a1e792c335 ("tools: bpftool: Allow all prog/map handles for pinning objects") > Signed-off-by: Pu Lehui > --- > tools/bpf/bpftool/common.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c > index e4d33bc8bbbf..653c130a0aaa 100644 > --- a/tools/bpf/bpftool/common.c > +++ b/tools/bpf/bpftool/common.c > @@ -302,6 +302,9 @@ int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***)) > int err; > int fd; > > + if (!REQ_ARGS(3)) > + return -EINVAL; > + > fd = get_fd(&argc, &argv); > if (fd < 0) > return fd; Good catch, and thanks for the fix! Reviewed-by: Quentin Monnet