From mboxrd@z Thu Jan 1 00:00:00 1970 From: Prarit Bhargava Subject: [PATCH] acpi/nfit: Fix memory corruption/Unregister mce decoder on failure Date: Wed, 17 May 2017 19:56:07 -0400 Message-ID: <1495065367-30551-1-git-send-email-prarit@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:34902 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752375AbdEQX4P (ORCPT ); Wed, 17 May 2017 19:56:15 -0400 Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-acpi@vger.kernel.org Cc: Prarit Bhargava , Jeff Moyer , "Rafael J. Wysocki" , Len Brown , Dan Williams , Vishal Verma , "Lee, Chun-Yi" , Linda Knippers nfit_init() calls nfit_mce_register() on module load. When the module load fails the nfit mce decoder is not unregistered. The module's memory is freed leaving the decoder chain referencing junk. This will cause panics as future registrations will reference the free'd memory. Only register the nfit mce decoder on success. Signed-off-by: Prarit Bhargava Cc: Jeff Moyer Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Dan Williams Cc: Vishal Verma Cc: "Lee, Chun-Yi" Cc: Linda Knippers --- drivers/acpi/nfit/core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 656acb5d7166..b60856b4325b 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -3043,6 +3043,8 @@ static void acpi_nfit_notify(struct acpi_device *adev, u32 event) static __init int nfit_init(void) { + int ret; + BUILD_BUG_ON(sizeof(struct acpi_table_nfit) != 40); BUILD_BUG_ON(sizeof(struct acpi_nfit_system_address) != 56); BUILD_BUG_ON(sizeof(struct acpi_nfit_memory_map) != 48); @@ -3069,9 +3071,11 @@ static __init int nfit_init(void) if (!nfit_wq) return -ENOMEM; - nfit_mce_register(); + ret = acpi_bus_register_driver(&acpi_nfit_driver); + if (!ret) + nfit_mce_register(); - return acpi_bus_register_driver(&acpi_nfit_driver); + return ret; } static __exit void nfit_exit(void) -- 1.7.9.3