From patchwork Sat Oct 12 08:53:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Zengkai X-Patchwork-Id: 13833963 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 2F4B4D1A451 for ; Sat, 12 Oct 2024 08:22:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=fCThfcsbNQi0aVIlgTyDdGTWvnsCQrxd0BHbcKmGnNw=; b=XPjJIjeNIYnZZitJ6DPe++mbDL IExBfopnUDgyL2Aqg7gpLB8MVSZBq7OEVU2eu8HS3O+46X2kJqxRSgayGlgFlR8HQtHdIcy2+gzRX 79KPAEsFpWYUpcw1+CXw6cKHvx4/NBcpa4gC/h43wcaN9YaGXdyDofVv5jrKzL/VkyqkNBIR//ht8 ZO39HDihLN8391dfujFoSwR4k3IpCBNANnFBj5m5dvfBo6IPExmfKuadSmgI6r8Pnw3XI6JT9gTF2 x4LX86tywaeEOgLkTe89yLfDDw1RV/dGxSmlKeBD8L3EVtwIu4PapieJzj7Vx0OD43XCNPuW+MNx7 NRqPt5WA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1szXNs-00000000oqJ-1Wir; Sat, 12 Oct 2024 08:21:56 +0000 Received: from szxga05-in.huawei.com ([45.249.212.191]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1szXMT-00000000oge-1s5I for linux-arm-kernel@lists.infradead.org; Sat, 12 Oct 2024 08:20:31 +0000 Received: from mail.maildlp.com (unknown [172.19.88.234]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4XQbt033J8z1HKrB; Sat, 12 Oct 2024 16:16:08 +0800 (CST) Received: from kwepemd200010.china.huawei.com (unknown [7.221.188.124]) by mail.maildlp.com (Postfix) with ESMTPS id 4AA741403D2; Sat, 12 Oct 2024 16:20:17 +0800 (CST) Received: from huawei.com (10.175.113.25) by kwepemd200010.china.huawei.com (7.221.188.124) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Sat, 12 Oct 2024 16:20:00 +0800 From: Zheng Zengkai To: , , , , , , CC: , , , , , Subject: [PATCH v2] ACPI: GTDT: Tighten the check for the array of platform timer structures Date: Sat, 12 Oct 2024 16:53:43 +0800 Message-ID: <20241012085343.6594-1-zhengzengkai@huawei.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Originating-IP: [10.175.113.25] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemd200010.china.huawei.com (7.221.188.124) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241012_012030_048554_5CAEE8BE X-CRM114-Status: GOOD ( 14.07 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org As suggested by Marc and Lorenzo, first we need to check whether the platform_timer entry pointer is within gtdt bounds (< gtdt_end) before de-referencing what it points at to detect the length of the platform timer struct and then check that the length of current platform_timer struct is within gtdt_end too. Now next_platform_timer() only checks against gtdt_end for the entry of subsequent platform timer without checking the length of it and will not report error if the check failed. Add check against table length (gtdt_end) for each element of platform timer array in acpi_gtdt_init() early, making sure that both their entry and length actually fit in the table. For the first platform timer, keep the check against the end of the acpi_table_gtdt struct, it is unnecessary for subsequent platform timer. Suggested-by: Marc Zyngier Suggested-by: Lorenzo Pieralisi Signed-off-by: Zheng Zengkai --- Changes in v2: - Check against gtdt_end for both entry and len of each array element v1: https://lore.kernel.org/all/20241010144703.113728-1-zhengzengkai@huawei.com/ --- drivers/acpi/arm64/gtdt.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c index c0e77c1c8e09..f5f62643899d 100644 --- a/drivers/acpi/arm64/gtdt.c +++ b/drivers/acpi/arm64/gtdt.c @@ -157,6 +157,8 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, { void *platform_timer; struct acpi_table_gtdt *gtdt; + struct acpi_gtdt_header *gh; + void *struct_end; gtdt = container_of(table, struct acpi_table_gtdt, header); acpi_gtdt_desc.gtdt = gtdt; @@ -177,11 +179,20 @@ int __init acpi_gtdt_init(struct acpi_table_header *table, } platform_timer = (void *)gtdt + gtdt->platform_timer_offset; - if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { - pr_err(FW_BUG "invalid timer data.\n"); - return -EINVAL; + struct_end = (void *)table + sizeof(struct acpi_table_gtdt); + for (int i = 0; i < gtdt->platform_timer_count; i++) { + gh = platform_timer; + if (((i == 0 && platform_timer >= struct_end) || i != 0) && + platform_timer < acpi_gtdt_desc.gtdt_end && + platform_timer + gh->length <= acpi_gtdt_desc.gtdt_end) { + platform_timer += gh->length; + } else { + pr_err(FW_BUG "invalid timer data.\n"); + return -EINVAL; + } } - acpi_gtdt_desc.platform_timer = platform_timer; + + acpi_gtdt_desc.platform_timer = (void *)gtdt + gtdt->platform_timer_offset; if (platform_timer_count) *platform_timer_count = gtdt->platform_timer_count;