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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 05AE610ED67D for ; Sat, 28 Mar 2026 07:41:59 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4fjTwX2yPmz2ysZ; Sat, 28 Mar 2026 18:41:32 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=113.46.200.217 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1774683692; cv=none; b=nQEJGe+6vhFubu6gr6FhL67kucEAOYkVrBdu7t+DWb2NKbA7EAwFWMueTJ1NuLdad2VQ/C1XFyuGP9+ny+aFmKegTpjCQ6Ytu+vA+hvHT+I9MeLRNPcMNE1FtKVfKGSWjntvlfBRHBgUbwr21mpp17AzRi13uHM5fJlZ+Zbc/3+XiQ64UpR87obYZnpDoty5TatXLBj0oPQ3hpwjpCOmObWcQoo28kr2vzjAMbx6N/J/OS0Stq6zksuX/CDr+jpIERvmIWIfIg49/zLkOFqctXHNwrs1QMouckDCvR3dCrEqU+FQNclkZ732AMtoZwJjYdpe19UFUEG8eOEbaSkxvg== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1774683692; c=relaxed/relaxed; bh=Czh3ZUxiO8h36fzYSD+B/184quE13gwwh24Rcl1WeUE=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=jTP+NdjIX1Z0W+JeXReORhpeyJOkl5irmWKvpfz8MScbGFP8bCG+uddd+ySkutu8AUL7280q+Rntuy2Torteo/QF0msp4PQF/rdV8KRpuwdKVwDVpBXtVHSOTgVAlmOo76idS4PZsYRpo8pmx3ReF8ULhWoUIHS6vo5WNQhgJfhT8++5BcMFnQq0ytaTklANo8T7riD9QXb46KRjQheoaWYBkUmXqFLYaHoyDypujbIqS4tZmeU3bAZZpKpcsNzwsEtXWECMRechUGR6IKp8wA+48ggVd2wBSzOkjeGugcAXOoXOwQaCKVIyf1IpHTfgOVp7WmDf24TbgbEJr3LkTQ== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; dkim=pass (1024-bit key; unprotected) header.d=huawei.com header.i=@huawei.com header.a=rsa-sha256 header.s=dkim header.b=WN1LG7zs; dkim-atps=neutral; spf=pass (client-ip=113.46.200.217; helo=canpmsgout02.his.huawei.com; envelope-from=ruanjinjie@huawei.com; receiver=lists.ozlabs.org) smtp.mailfrom=huawei.com Authentication-Results: lists.ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=huawei.com header.i=@huawei.com header.a=rsa-sha256 header.s=dkim header.b=WN1LG7zs; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=huawei.com (client-ip=113.46.200.217; helo=canpmsgout02.his.huawei.com; envelope-from=ruanjinjie@huawei.com; receiver=lists.ozlabs.org) Received: from canpmsgout02.his.huawei.com (canpmsgout02.his.huawei.com [113.46.200.217]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4fjTwW3D0Wz2ypm for ; Sat, 28 Mar 2026 18:41:31 +1100 (AEDT) dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=Czh3ZUxiO8h36fzYSD+B/184quE13gwwh24Rcl1WeUE=; b=WN1LG7zshWXEBEhlTe0GLE+YtWu+Bdx8VViXltUaEPeep1PwAfKwMUt562Zfs6cTIxrMU4iqC ku/ZUtfEbNjDE7THntsNA6FovG2HnyRDGfH5HpXM7LL0HNhfrC5420nrYjlKHZLapttYP+PmcRX oIzuOag+CVRjztDn6RsHktA= Received: from mail.maildlp.com (unknown [172.19.162.223]) by canpmsgout02.his.huawei.com (SkyGuard) with ESMTPS id 4fjTnZ5MNHzcb0t; Sat, 28 Mar 2026 15:35:30 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id E0BB840569; Sat, 28 Mar 2026 15:41:27 +0800 (CST) Received: from huawei.com (10.90.53.73) by dggpemf500011.china.huawei.com (7.185.36.131) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Sat, 28 Mar 2026 15:41:25 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH v11 04/11] arm64: kexec_file: Fix potential buffer overflow in prepare_elf_headers() Date: Sat, 28 Mar 2026 15:40:06 +0800 Message-ID: <20260328074013.3589544-5-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260328074013.3589544-1-ruanjinjie@huawei.com> References: <20260328074013.3589544-1-ruanjinjie@huawei.com> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: kwepems100001.china.huawei.com (7.221.188.238) To dggpemf500011.china.huawei.com (7.185.36.131) There is a race condition between the kexec_load() system call (crash kernel loading path) and memory hotplug operations that can lead to buffer overflow and potential kernel crash. During prepare_elf_headers(), the following steps occur: 1. The first for_each_mem_range() queries current System RAM memory ranges 2. Allocates buffer based on queried count 3. The 2st for_each_mem_range() populates ranges from memblock If memory hotplug occurs between step 1 and step 3, the number of ranges can increase, causing out-of-bounds write when populating cmem->ranges[]. This happens because kexec_load() uses kexec_trylock (atomic_t) while memory hotplug uses device_hotplug_lock (mutex), so they don't serialize with each other. Just add bounds checking to prevent out-of-bounds access. Fixes: 3751e728cef2 ("arm64: kexec_file: add crash dump support") Signed-off-by: Jinjie Ruan --- arch/arm64/kernel/machine_kexec_file.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c index fba260ad87a9..df52ac4474c9 100644 --- a/arch/arm64/kernel/machine_kexec_file.c +++ b/arch/arm64/kernel/machine_kexec_file.c @@ -59,6 +59,11 @@ static int prepare_elf_headers(void **addr, unsigned long *sz) cmem->max_nr_ranges = nr_ranges; cmem->nr_ranges = 0; for_each_mem_range(i, &start, &end) { + if (cmem->nr_ranges >= cmem->max_nr_ranges) { + ret = -ENOMEM; + goto out; + } + cmem->ranges[cmem->nr_ranges].start = start; cmem->ranges[cmem->nr_ranges].end = end - 1; cmem->nr_ranges++; -- 2.34.1