From patchwork Tue Oct 18 12:25:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christopher Friedt X-Patchwork-Id: 13010479 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 52420C4332F for ; Tue, 18 Oct 2022 12:44:43 +0000 (UTC) Received: from localhost ([::1]:57934 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oklxa-0001S0-4m for qemu-devel@archiver.kernel.org; Tue, 18 Oct 2022 08:44:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42160) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oklgk-0003FT-Qy for qemu-devel@nongnu.org; Tue, 18 Oct 2022 08:27:18 -0400 Received: from mail-qt1-x82b.google.com ([2607:f8b0:4864:20::82b]:34516) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1oklgj-0000y5-1N for qemu-devel@nongnu.org; Tue, 18 Oct 2022 08:27:18 -0400 Received: by mail-qt1-x82b.google.com with SMTP id g11so9494520qts.1 for ; Tue, 18 Oct 2022 05:27:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=Ae8hPehpjUNhf7+xT0HR9r3tNqUK3me++rgVmdi5DaU=; b=D3CqOq9Ec8wvHvNN7Dwlf9G0PKJPJMkJ+580zF8bL2UgTYZbJQ84JwiRVbQSKP9BbZ 0wbdhu6riZh8eSplPwUUPrj9bdcPD2g77ykSfKcmNrJZ6LcUxdJmHgTAZJsUwXr+g7d+ BdL1SNmhUVXASCIxdd6aUpqWDTrJBfH77NZQlSBiPvseQ0/Ed0j6TzHMreStLDc2Zw7p j0kSaEZK5qS4xXUzbg+ZEIAWAavswlVmkbb3J6UL8nFPKEle6DeaH+qQ531Xj54oFmm+ MT4N2DmBywDTprn5n8EhtcSR+3l4uHCKLs4Wtfw4FnxKCoi1CWeiw6zfBfT355/SQ7Jx JO2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Ae8hPehpjUNhf7+xT0HR9r3tNqUK3me++rgVmdi5DaU=; b=qVjtjlLpjXv5+qZhomA/KUfDe/c1vBR9zEiajiPwvzv1zYXF7KWEvk/mudLwEwaHyP k+BYd33qOsAr3OywyIcR/HmB1ljFg2Ao8BzAw8RDrFQo5UNp/f1I0xCR0AEK4bwtcyKr oayaYXvua/YyLQhv4HvGJA41NK95W+locFnMDEjeO96ReJd+YBJFTqwUvjLK+Rf3X5Iu PnMzlQNsIXNIECdh1TBPfedySMm7dUiBo4IwvpkT88/QFw7QtPMuA8WMw0YOb+m7mhXa JoYQ1BuSNNYowrDz06vLeS0o7olGiWSez8Gep07zE+5xpEWeM1A7jAGlHUt0vycDsU2d 12Fg== X-Gm-Message-State: ACrzQf19QnRbXQbWa5IXeVka0K/szUKKQbUDbxv9x+X3I7XpV5EcgJpa mq5bhiHescwx9KG+BocZlSf+pLz3+1F0zA== X-Google-Smtp-Source: AMsMyM7q7FVs9NtxZnUPV+xqQ29YNmW9PMiXe8I6jSeKDF2dNdIh4vJ0ki2sd0qTWsU0RNOD8+mUpg== X-Received: by 2002:a05:622a:3c6:b0:35d:4335:f060 with SMTP id k6-20020a05622a03c600b0035d4335f060mr1820442qtx.326.1666096034668; Tue, 18 Oct 2022 05:27:14 -0700 (PDT) Received: from localhost.localdomain ([2001:1970:50d6:9900::a196]) by smtp.gmail.com with ESMTPSA id h7-20020a05620a284700b006ecb9dfdd15sm2276248qkp.92.2022.10.18.05.27.12 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Tue, 18 Oct 2022 05:27:13 -0700 (PDT) From: Chris Friedt X-Google-Original-From: Chris Friedt To: qemu-devel@nongnu.org Cc: cfriedt@meta.com, jslaby@suse.cz Subject: [PATCH v4 1/3] hw: misc: edu: fix 2 off-by-one errors Date: Tue, 18 Oct 2022 08:25:49 -0400 Message-Id: <20221018122551.94567-1-cfriedt@meta.com> X-Mailer: git-send-email 2.36.1 MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::82b; envelope-from=chrisfriedt@gmail.com; helo=mail-qt1-x82b.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" In the case that size1 was zero, because of the explicit 'end1 > addr' check, the range check would fail and the error message would read as shown below. The correct comparison is 'end1 >= addr'. EDU: DMA range 0x40000-0x3ffff out of bounds (0x40000-0x40fff)! At the opposite end, in the case that size1 was 4096, within() would fail because of the non-inclusive check 'end1 < end2', which should have been 'end1 <= end2'. The error message would previously say EDU: DMA range 0x40000-0x40fff out of bounds (0x40000-0x40fff)! Signed-off-by: Chris Friedt --- hw/misc/edu.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/hw/misc/edu.c b/hw/misc/edu.c index e935c418d4..b3de8d206a 100644 --- a/hw/misc/edu.c +++ b/hw/misc/edu.c @@ -103,19 +103,18 @@ static void edu_lower_irq(EduState *edu, uint32_t val) } } -static bool within(uint64_t addr, uint64_t start, uint64_t end) -{ - return start <= addr && addr < end; -} - -static void edu_check_range(uint64_t addr, uint64_t size1, uint64_t start, - uint64_t size2) +static void edu_check_range(uint64_t addr, uint64_t size1, + uint64_t start, uint64_t size2) { uint64_t end1 = addr + size1; uint64_t end2 = start + size2; - if (within(addr, start, end2) && - end1 > addr && within(end1, start, end2)) { + /* + * 1. ensure we aren't overflowing + * 2. ensure that [addr, end1) is within [start, size2) + */ + if (end2 >= start && end1 >= addr && + addr >= start && end1 <= end2) { return; }