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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 71B30C433E0 for ; Tue, 26 May 2020 18:58:57 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1317020849 for ; Tue, 26 May 2020 18:58:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="UOcPDtb/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1317020849 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id CEFF2868E1; Tue, 26 May 2020 18:58:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id v7jvXxPH4Of1; Tue, 26 May 2020 18:58:55 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id CC8D786868; Tue, 26 May 2020 18:58:55 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id BEE86C0888; Tue, 26 May 2020 18:58:55 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id EBC8BC016F for ; Tue, 26 May 2020 18:58:54 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id D47D7868CF for ; Tue, 26 May 2020 18:58:54 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id AEWWTydsSnVV for ; Tue, 26 May 2020 18:58:52 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by fraxinus.osuosl.org (Postfix) with ESMTPS id EECF086868 for ; Tue, 26 May 2020 18:58:52 +0000 (UTC) Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3AED620849; Tue, 26 May 2020 18:58:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519532; bh=SBO2CtJOq45C8dSvcgZYZQrfHJFowCVleqXEM/AknR0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UOcPDtb/Tg3xEezj0VM02Jg+l9ThNoUExBL4vDyiFDqjJPnxDz6IQtM10E6ijeQ7i UsOx6Dgt7sXuskF3sfVf4tIaqoBmAH/kaBfeEmgOQAFIioU2fXrlnFC0MDGQSw3N87 ZJVNDmoP4WVpdFjubNHIZr50PpnKN4PhG24w7eT0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Subject: [PATCH 4.9 09/64] iommu/amd: Fix over-read of ACPI UID from IVRS table Date: Tue, 26 May 2020 20:52:38 +0200 Message-Id: <20200526183917.314759956@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183913.064413230@linuxfoundation.org> References: <20200526183913.064413230@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Cc: Sasha Levin , Joerg Roedel , Greg Kroah-Hartman , Alexander Monakov , stable@vger.kernel.org, iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" From: Alexander Monakov [ Upstream commit e461b8c991b9202b007ea2059d953e264240b0c9 ] IVRS parsing code always tries to read 255 bytes from memory when retrieving ACPI device path, and makes an assumption that firmware provides a zero-terminated string. Both of those are bugs: the entry is likely to be shorter than 255 bytes, and zero-termination is not guaranteed. With Acer SF314-42 firmware these issues manifest visibly in dmesg: AMD-Vi: ivrs, add hid:AMDI0020, uid:\_SB.FUR0\xf0\xa5, rdevid:160 AMD-Vi: ivrs, add hid:AMDI0020, uid:\_SB.FUR1\xf0\xa5, rdevid:160 AMD-Vi: ivrs, add hid:AMDI0020, uid:\_SB.FUR2\xf0\xa5, rdevid:160 AMD-Vi: ivrs, add hid:AMDI0020, uid:\_SB.FUR3>\x83e\x8d\x9a\xd1... The first three lines show how the code over-reads adjacent table entries into the UID, and in the last line it even reads garbage data beyond the end of the IVRS table itself. Since each entry has the length of the UID (uidl member of ivhd_entry struct), use that for memcpy, and manually add a zero terminator. Avoid zero-filling hid and uid arrays up front, and instead ensure the uid array is always zero-terminated. No change needed for the hid array, as it was already properly zero-terminated. Fixes: 2a0cb4e2d423c ("iommu/amd: Add new map for storing IVHD dev entry type HID") Signed-off-by: Alexander Monakov Cc: Joerg Roedel Cc: iommu@lists.linux-foundation.org Link: https://lore.kernel.org/r/20200511102352.1831-1-amonakov@ispras.ru Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/amd_iommu_init.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index e6ae8d123984..a3279f303b49 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1171,8 +1171,8 @@ static int __init init_iommu_from_acpi(struct amd_iommu *iommu, } case IVHD_DEV_ACPI_HID: { u16 devid; - u8 hid[ACPIHID_HID_LEN] = {0}; - u8 uid[ACPIHID_UID_LEN] = {0}; + u8 hid[ACPIHID_HID_LEN]; + u8 uid[ACPIHID_UID_LEN]; int ret; if (h->type != 0x40) { @@ -1189,6 +1189,7 @@ static int __init init_iommu_from_acpi(struct amd_iommu *iommu, break; } + uid[0] = '\0'; switch (e->uidf) { case UID_NOT_PRESENT: @@ -1203,8 +1204,8 @@ static int __init init_iommu_from_acpi(struct amd_iommu *iommu, break; case UID_IS_CHARACTER: - memcpy(uid, (u8 *)(&e->uid), ACPIHID_UID_LEN - 1); - uid[ACPIHID_UID_LEN - 1] = '\0'; + memcpy(uid, &e->uid, e->uidl); + uid[e->uidl] = '\0'; break; default: -- 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu