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 EF77410BA424 for ; Sat, 28 Mar 2026 07:42:12 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4fjTwd3J9Sz2yv0; Sat, 28 Mar 2026 18:41:37 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=113.46.200.226 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1774683697; cv=none; b=InZZVCG+0xom5X7axT7buaAEE37aYsfnH8cmyE90/SUFfLQAJXVs190hbIhp5uEmlwQxkAFMBggKTGfjL53jRzaZv84SyySNnAXYr5D+bq2MDyrvUdVM8MhKSSsTXy+Z8shSqWMPaAGzQcqjdkM5kAXvKh+wM8ZaRczQqtmB+94DCphkblnyB9noYWC8VXdvgn8KEXaVjkT/FYTeC0CSSLiI5xurm3BcK5swLDOHqtQMFH6FVNud+mfQ7DU8Tesd9KJ/F1CuPysS7fSYdE5fw9IdV5Fb0cIPu+pltlJY6qmcpBATUSNB1bxM8903ryiHHk2TCnUZP0HdWyI17THQpw== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1774683697; c=relaxed/relaxed; bh=7Kwc6kWIjE6MMFJP+OfVcLTnCUv+ekJ3y6ZVFx802F8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=kRJJDSetPkkL85rCymb8v/WC82HPxP2CRGHjYj3jiw+5CtKDPFJLBpLq4EBTnAtUVQZOqJjW2BA5ey1TFE3VpUc7eqb6IRC5kz3m5xwAwLcKa+jRk060A7SpNmTkLRB+Lo/q/GcByTdjcZp3yA7Dw/ITsfvXCz5XcF55qTCfP7pUVxMXST/uTR3IwfdbBiSGc1HM8HqrZsBTXUsNXzFF4CCenjuw8Pkm+NW1u78pGD6a1uS+qARi4kE/ZgHV2uLbyH/RfRdUM0BMyjw3Y4iINEx8nHjiARBqfM0iVJqhh6OY3K4bZtiUiU/+JLcoWJWOWyOxCL0opCtKVy9VLeGzUA== 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=rPlh5l6P; dkim-atps=neutral; spf=pass (client-ip=113.46.200.226; helo=canpmsgout11.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=rPlh5l6P; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=huawei.com (client-ip=113.46.200.226; helo=canpmsgout11.his.huawei.com; envelope-from=ruanjinjie@huawei.com; receiver=lists.ozlabs.org) Received: from canpmsgout11.his.huawei.com (canpmsgout11.his.huawei.com [113.46.200.226]) (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 4fjTwc4K4tz2ygm for ; Sat, 28 Mar 2026 18:41:36 +1100 (AEDT) dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=7Kwc6kWIjE6MMFJP+OfVcLTnCUv+ekJ3y6ZVFx802F8=; b=rPlh5l6P/r0lCaYwhte4yShjLrdwYBNU0lmIIgw5zLcvDsIThOK9DhT/uaKtGrhCHIM2m/T2E E/c7DL3vdFGbipfioCcdgsazyLS5iJjEmcOCqlzDVeWHjNYlk59gPZS+xwcmZ6tAuW17/cQDjHA 1aexox4eHyMo0rEmFdCoOYA= Received: from mail.maildlp.com (unknown [172.19.163.214]) by canpmsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4fjTnS2VF4zKm6V; Sat, 28 Mar 2026 15:35:24 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id 850984056C; Sat, 28 Mar 2026 15:41:33 +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 15:41:30 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH v11 06/11] LoongArch: kexec: Fix potential buffer overflow in prepare_elf_headers() Date: Sat, 28 Mar 2026 15:40:08 +0800 Message-ID: <20260328074013.3589544-7-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: 1bcca8620a91 ("LoongArch: Add crash dump support for kexec_file") Signed-off-by: Jinjie Ruan --- arch/loongarch/kernel/machine_kexec_file.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/kernel/machine_kexec_file.c index 5584b798ba46..167392c1da33 100644 --- a/arch/loongarch/kernel/machine_kexec_file.c +++ b/arch/loongarch/kernel/machine_kexec_file.c @@ -75,6 +75,11 @@ 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