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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 3F93AC433DB for ; Fri, 19 Feb 2021 09:53:29 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8BFEC64E4B for ; Fri, 19 Feb 2021 09:53:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8BFEC64E4B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=weilnetz.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46062 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lD2TX-0000fk-CE for qemu-devel@archiver.kernel.org; Fri, 19 Feb 2021 04:53:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:52430) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lD2SP-0008DF-Vu for qemu-devel@nongnu.org; Fri, 19 Feb 2021 04:52:17 -0500 Received: from mail.weilnetz.de ([37.120.169.71]:42896 helo=mail.v2201612906741603.powersrv.de) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lD2SH-0002DK-9g for qemu-devel@nongnu.org; Fri, 19 Feb 2021 04:52:17 -0500 Received: from edv-macbook-pro.fritz.box (p5b1511bf.dip0.t-ipconnect.de [91.21.17.191]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.v2201612906741603.powersrv.de (Postfix) with ESMTPSA id B2654DA0BCD; Fri, 19 Feb 2021 10:52:06 +0100 (CET) Subject: Re: [PATCH] net: eepro100: validate various address values To: P J P References: <20210218140629.373646-1-ppandit@redhat.com> <20210219015403.tl5upltt3d2bnmw5@mozz.bu.edu> <6qo84891-7or2-7p58-rr4-n2n46o5730rq@erqung.pbz> <00338810-b72e-6a9c-eef0-3c0adc764695@weilnetz.de> <43340d92-55da-61f2-5ad1-c8e3d6679f6d@weilnetz.de> From: Stefan Weil Message-ID: <89da11b8-cecf-d161-2dfc-d62a7edd0356@weilnetz.de> Date: Fri, 19 Feb 2021 10:52:05 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=37.120.169.71; envelope-from=sw@weilnetz.de; helo=mail.v2201612906741603.powersrv.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Jason Wang , Li Qiang , QEMU Developers , Alexander Bulekov , Ruhr-University Bochum Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 19.02.21 um 10:26 schrieb P J P: > Hello Stefan, > > +-- On Fri, 19 Feb 2021, Stefan Weil wrote --+ > | If there are no recursions in normal use, the following patch should work: > | > | diff --git a/hw/net/eepro100.c b/hw/net/eepro100.c > | index 16e95ef9cc..2474cf3dc2 100644 > | --- a/hw/net/eepro100.c > | +++ b/hw/net/eepro100.c > | @@ -279,6 +279,9 @@ typedef struct { > |      /* Quasi static device properties (no need to save them). */ > |      uint16_t stats_size; > |      bool has_extended_tcb_support; > | + > | +    /* Flag to avoid recursions. */ > | +    bool busy; > |  } EEPRO100State; > | > |  /* Word indices in EEPROM. */ > | @@ -837,6 +840,14 @@ static void action_command(EEPRO100State *s) > |         Therefore we limit the number of iterations. */ > |      unsigned max_loop_count = 16; > | > | +    if (s->busy) { > | +        /* Prevent recursions. */ > | +        logout("recursion in %s:%u\n", __FILE__, __LINE__); > | +        return; > | +    } > | + > | +    s->busy = true; > | + > |      for (;;) { > |          bool bit_el; > |          bool bit_s; > | @@ -933,6 +944,7 @@ static void action_command(EEPRO100State *s) > |      } > |      TRACE(OTHER, logout("CU list empty\n")); > |      /* List is empty. Now CU is idle or suspended. */ > | +    s->busy = false; > |  } > | > |  static void eepro100_cu_command(EEPRO100State * s, uint8_t val) > > Please see: > -> https://ruhr-uni-bochum.sciebo.de/s/NNWP2GfwzYKeKwE?path=%2Feepro100_stackoverflow1 > > * It does not seem to address above case. My suggested patch fixes that test case: it no longer crashes because of an endless recursion. Stefan