From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vishal Verma Subject: [PATCH v2 1/2] nfit: in acpi_nfit_init, break on a 0-length table Date: Wed, 14 Oct 2015 17:04:25 -0600 Message-ID: <1444863866-19173-2-git-send-email-vishal.l.verma@intel.com> References: <1444863866-19173-1-git-send-email-vishal.l.verma@intel.com> Return-path: Received: from mga09.intel.com ([134.134.136.24]:9510 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753988AbbJNXEs (ORCPT ); Wed, 14 Oct 2015 19:04:48 -0400 In-Reply-To: <1444863866-19173-1-git-send-email-vishal.l.verma@intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-nvdimm@lists.01.org Cc: linux-acpi@vger.kernel.org, Dan Williams , "Rafael J. Wysocki" , Toshi Kani , Elliott Robert , Vishal Verma If acpi_nfit_init is called (such as from nfit_test), with an nfit table that has more memory allocated than it needs (and a similarly large 'size' field, add_tables would happily keep adding null SPA Range tables filling up all available memory. Make it friendlier by breaking out if a 0-length header is found in any of the tables. Cc: Dan Williams Cc: Rafael J. Wysocki Cc: Cc: Signed-off-by: Vishal Verma --- drivers/acpi/nfit.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c index c1b8d03..35b4b56 100644 --- a/drivers/acpi/nfit.c +++ b/drivers/acpi/nfit.c @@ -335,6 +335,12 @@ static void *add_table(struct acpi_nfit_desc *acpi_desc, void *table, return NULL; hdr = table; + if (!hdr->length) { + dev_warn(dev, "found a zero length table '%d' parsing nfit\n", + hdr->type); + return NULL; + } + switch (hdr->type) { case ACPI_NFIT_TYPE_SYSTEM_ADDRESS: if (!add_spa(acpi_desc, table)) -- 2.4.3