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 X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 415C5C43333 for ; Mon, 1 Mar 2021 23:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F66360C3E for ; Mon, 1 Mar 2021 23:05:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344713AbhCAXCE (ORCPT ); Mon, 1 Mar 2021 18:02:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:46486 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238941AbhCARvl (ORCPT ); Mon, 1 Mar 2021 12:51:41 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7C9F964F5C; Mon, 1 Mar 2021 17:00:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614618041; bh=AILuiiJz2E4g9lh2Umst2pD5abNWxIQz3SJ8yvZQKfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ackiTZLC1YvNLbRj0pIBPtpb259ek5eyNGO+E8pV6FhJckEQfSfwetWzLuXWvWqmF I3DlLfFSXjFBQZX8/M5jC6B6mAQscKIVN1tgfECWwPBK6Utw+aVNv7CzBsqEE50TXm M9A6byZmF6w6RasxypiKwoYfHcQPrn/RWVT8wDZI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Fabiano Rosas , Michael Ellerman Subject: [PATCH 5.4 286/340] powerpc/prom: Fix "ibm,arch-vec-5-platform-support" scan Date: Mon, 1 Mar 2021 17:13:50 +0100 Message-Id: <20210301161102.365968218@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161048.294656001@linuxfoundation.org> References: <20210301161048.294656001@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Cédric Le Goater commit ed5b00a05c2ae95b59adc3442f45944ec632e794 upstream. The "ibm,arch-vec-5-platform-support" property is a list of pairs of bytes representing the options and values supported by the platform firmware. At boot time, Linux scans this list and activates the available features it recognizes : Radix and XIVE. A recent change modified the number of entries to loop on and 8 bytes, 4 pairs of { options, values } entries are always scanned. This is fine on KVM but not on PowerVM which can advertises less. As a consequence on this platform, Linux reads extra entries pointing to random data, interprets these as available features and tries to activate them, leading to a firmware crash in ibm,client-architecture-support. Fix that by using the property length of "ibm,arch-vec-5-platform-support". Fixes: ab91239942a9 ("powerpc/prom: Remove VLA in prom_check_platform_support()") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Cédric Le Goater Reviewed-by: Fabiano Rosas Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210122075029.797013-1-clg@kaod.org Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/prom_init.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -1305,14 +1305,10 @@ static void __init prom_check_platform_s if (prop_len > sizeof(vec)) prom_printf("WARNING: ibm,arch-vec-5-platform-support longer than expected (len: %d)\n", prop_len); - prom_getprop(prom.chosen, "ibm,arch-vec-5-platform-support", - &vec, sizeof(vec)); - for (i = 0; i < sizeof(vec); i += 2) { - prom_debug("%d: index = 0x%x val = 0x%x\n", i / 2 - , vec[i] - , vec[i + 1]); - prom_parse_platform_support(vec[i], vec[i + 1], - &supported); + prom_getprop(prom.chosen, "ibm,arch-vec-5-platform-support", &vec, sizeof(vec)); + for (i = 0; i < prop_len; i += 2) { + prom_debug("%d: index = 0x%x val = 0x%x\n", i / 2, vec[i], vec[i + 1]); + prom_parse_platform_support(vec[i], vec[i + 1], &supported); } }