From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758451Ab3E1VnB (ORCPT ); Tue, 28 May 2013 17:43:01 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59529 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757031Ab3E1VVV (ORCPT ); Tue, 28 May 2013 17:21:21 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Bob Moore , Lv Zheng , "Rafael J. Wysocki" , Kamal Mostafa Subject: [PATCH 20/78] ACPICA: Fix possible buffer overflow during a field unit read operation Date: Tue, 28 May 2013 14:19:29 -0700 Message-Id: <1369776027-17859-21-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1369776027-17859-1-git-send-email-kamal@canonical.com> References: <1369776027-17859-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Bob Moore commit 61388f9e5d93053cf399a356414f31f9b4814c6d upstream. Can only happen under these conditions: 1) The DSDT version is 1, meaning integers are 32-bits. 2) The field is between 33 and 64 bits long. It applies cleanly back to ACPICA 20100806+ (Linux v2.6.37+). Signed-off-by: Bob Moore Signed-off-by: Lv Zheng Signed-off-by: Rafael J. Wysocki Signed-off-by: Kamal Mostafa --- drivers/acpi/acpica/exfldio.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/acpica/exfldio.c b/drivers/acpi/acpica/exfldio.c index aa2ccfb..142fdd0 100644 --- a/drivers/acpi/acpica/exfldio.c +++ b/drivers/acpi/acpica/exfldio.c @@ -721,7 +721,19 @@ acpi_ex_extract_from_field(union acpi_operand_object *obj_desc, if ((obj_desc->common_field.start_field_bit_offset == 0) && (obj_desc->common_field.bit_length == access_bit_width)) { - status = acpi_ex_field_datum_io(obj_desc, 0, buffer, ACPI_READ); + if (buffer_length >= sizeof(u64)) { + status = + acpi_ex_field_datum_io(obj_desc, 0, buffer, + ACPI_READ); + } else { + /* Use raw_datum (u64) to handle buffers < 64 bits */ + + status = + acpi_ex_field_datum_io(obj_desc, 0, &raw_datum, + ACPI_READ); + ACPI_MEMCPY(buffer, &raw_datum, buffer_length); + } + return_ACPI_STATUS(status); } -- 1.8.1.2