From patchwork Fri Feb 24 02:36:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Weichen Chen X-Patchwork-Id: 13150891 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD3EBC64ED6 for ; Fri, 24 Feb 2023 02:38:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229644AbjBXCiY (ORCPT ); Thu, 23 Feb 2023 21:38:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229551AbjBXCiX (ORCPT ); Thu, 23 Feb 2023 21:38:23 -0500 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB3E2199FA; Thu, 23 Feb 2023 18:38:17 -0800 (PST) X-UUID: 47fa8012b3ec11eda06fc9ecc4dadd91-20230224 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:Message-ID:Date:Subject:To:From; bh=B4U1+Q/UYoJiKUsQ/RT3eOwBmSrlf5qH2DnCuR/+E3Y=; b=DVI9z2vNQ3XpIsjTjW+N8kG70w0c0zrcAqXdQbyRkG7WJVZIvyw5yHOCNkJ3VZn7REXB3AQvF7JcPi6rtZ+2W6/gRfQmOOOF5Fkb1bpqRYG4OO+2YEAY4fWlmRqjsGQ3lsDbYmQiv5KzxpD4NKTtnYssKM3wWC16bmDL65m0zBc=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.20,REQID:403977e8-6d1a-4c0d-9f0a-0a72fd6328a7,IP:0,U RL:0,TC:0,Content:0,EDM:-30,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-30 X-CID-META: VersionHash:25b5999,CLOUDID:e93e6db1-beed-4dfc-bd9c-e1b22fa6ccc4,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:2,IP:nil,UR L:0,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0 X-CID-BVR: 0 X-UUID: 47fa8012b3ec11eda06fc9ecc4dadd91-20230224 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1515731948; Fri, 24 Feb 2023 10:38:11 +0800 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs13n2.mediatek.inc (172.21.101.108) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.15; Fri, 24 Feb 2023 10:38:09 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.15 via Frontend Transport; Fri, 24 Feb 2023 10:38:09 +0800 From: Weichen Chen To: , , , , , , , , , Subject: [PATCH v1 1/1] pstore/ram: Fix crash when setting number of cpus to an odd number Date: Fri, 24 Feb 2023 10:36:32 +0800 Message-ID: <20230224023632.6840-1-weichen.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org When the number of cpu cores is adjusted to 7 or other odd numbers, the zone size will become an odd number. The address of the zone will become: addr of zone0 = BASE addr of zone1 = BASE + zone_size addr of zone2 = BASE + zone_size*2 ... The address of zone1/3/5/7 will be mapped to non-alignment va. Eventually crashes will occur when accessing these va. So, use ALIGN_DOWN() to make sure the zone size is even to avoid this bug. Signed-off-by: Weichen Chen Tested-by: Guilherme G. Piccoli Reviewed-by: Matthias Brugger --- fs/pstore/ram.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index ade66dbe5f39..fc57ac97e506 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -528,6 +528,7 @@ static int ramoops_init_przs(const char *name, } zone_sz = mem_sz / *cnt; + zone_sz = ALIGN_DOWN(zone_sz, 2); if (!zone_sz) { dev_err(dev, "%s zone size == 0\n", name); goto fail;