From patchwork Wed May 29 13:34:39 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 13678879 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 2B9D0C25B75 for ; Wed, 29 May 2024 13:41:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: 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: List-Owner; bh=Auez8nwTJHcudqNHBkn1JfYIqvEx5lMegLeWw2HeMRo=; b=JTe+pTdoMEdmrA inNeLFlfyUuUyC4VRzo5+NuJa/ONDXAh5CZHejPHtoojUyrI5oOXLMk6EWRrKW0B284jsM1rQcDOZ 1lFnmYOADI0R2a4pHisA+cewkCXXRfNUn/RF0+yuygT0NRCbQynjU0XPdy4vnc+2lh6YXYy88egXM yDnyocMpjaOAFQyBnxnOjl9lR0qtv6C02QiC8zJKeciz9BkdTUXGcL6XjgBET03YzCVvtk+Se77Q1 0YMC8yCpryQD0n5BpuRAC20HgH0X0UcZgupxTQaTTU8rU5NK0AXtZs0B9I+Nuzj/IaWUSom6R8wwD 7duCn+1EES8TZ3LA4GbQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sCJY7-00000004JAi-3bRv; Wed, 29 May 2024 13:41:03 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sCJY4-00000004J8w-2CyV for linux-arm-kernel@lists.infradead.org; Wed, 29 May 2024 13:41:01 +0000 Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Vq9Qh6LRGz6J6m1; Wed, 29 May 2024 21:36:44 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 0F0C5140DDB; Wed, 29 May 2024 21:40:59 +0800 (CST) Received: from SecurePC-101-06.china.huawei.com (10.122.247.231) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Wed, 29 May 2024 14:40:58 +0100 From: Jonathan Cameron To: Marc Zyngier , Will Deacon , Catalin Marinas , , , , , CC: Mark Rutland , Thomas Gleixner , Peter Zijlstra , , , Russell King , "Rafael J . Wysocki" , Miguel Luis , James Morse , Salil Mehta , Jean-Philippe Brucker , Hanjun Guo , Gavin Shan , Ingo Molnar , Borislav Petkov , Dave Hansen , , , Subject: [PATCH v10 12/19] arm64: acpi: Harden get_cpu_for_acpi_id() against missing CPU entry Date: Wed, 29 May 2024 14:34:39 +0100 Message-ID: <20240529133446.28446-13-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240529133446.28446-1-Jonathan.Cameron@huawei.com> References: <20240529133446.28446-1-Jonathan.Cameron@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhrpeml100001.china.huawei.com (7.191.160.183) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240529_064100_729932_2818FAC8 X-CRM114-Status: GOOD ( 14.60 ) 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 In a review discussion of the changes to support vCPU hotplug where a check was added on the GICC being enabled if was online, it was noted that there is need to map back to the cpu and use that to index into a cpumask. As such, a valid ID is needed. If an MPIDR check fails in acpi_map_gic_cpu_interface() it is possible for the entry in cpu_madt_gicc[cpu] == NULL. This function would then cause a NULL pointer dereference. Whilst a path to trigger this has not been established, harden this caller against the possibility. Reviewed-by: Gavin Shan Signed-off-by: Jonathan Cameron --- V10: Fix description above (duplicated word). Picked up Gavin's tag. --- arch/arm64/include/asm/acpi.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index bc9a6656fc0c..a407f9cd549e 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -124,7 +124,8 @@ static inline int get_cpu_for_acpi_id(u32 uid) int cpu; for (cpu = 0; cpu < nr_cpu_ids; cpu++) - if (uid == get_acpi_id_for_cpu(cpu)) + if (acpi_cpu_get_madt_gicc(cpu) && + uid == get_acpi_id_for_cpu(cpu)) return cpu; return -EINVAL;