From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: Re: [PATCH] x86/acpi: check rsdp address received via bootparams to be valid Date: Wed, 17 Jan 2018 13:20:01 +0100 Message-ID: <23728a6c-b820-4d37-d522-1a70b4304d28@suse.com> References: <20180116135730.19216-1-jgross@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.suse.de ([195.135.220.15]:56594 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775AbeAQMUE (ORCPT ); Wed, 17 Jan 2018 07:20:04 -0500 In-Reply-To: Content-Language: de-DE Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: Linux Kernel Mailing List , ACPI Devel Maling List , the arch/x86 maintainers , Len Brown , Rafael Wysocki , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar On 17/01/18 12:49, Rafael J. Wysocki wrote: > On Tue, Jan 16, 2018 at 2:57 PM, Juergen Gross wrote: >> There seem to exist several grub2 versions trashing >> boot_params.hdr.acpi_rsdp_addr. >> >> So don't just believe this address to be valid, but verify it pointing >> to a valid RSDP table. >> >> Signed-off-by: Juergen Gross >> --- >> To be applied on top of my RSDP series currently in tip.git x86/boot >> Mike Galbraith has tested this patch to repair his broken boot >> --- >> drivers/acpi/acpica/tbxfroot.c | 36 ++++++++++++++++++++++++++++++++++++ >> drivers/acpi/osl.c | 2 +- >> include/acpi/acpixf.h | 5 +++++ >> 3 files changed, 42 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/acpi/acpica/tbxfroot.c b/drivers/acpi/acpica/tbxfroot.c >> index f9f9a7da2cad..9edc71780a38 100644 >> --- a/drivers/acpi/acpica/tbxfroot.c >> +++ b/drivers/acpi/acpica/tbxfroot.c >> @@ -249,6 +249,42 @@ ACPI_EXPORT_SYMBOL_INIT(acpi_find_root_pointer) >> >> /******************************************************************************* >> * >> + * FUNCTION: acpi_verify_root_pointer > > Why do you want this to go into ACPICA? It seemed to fit in here. >> + * >> + * >> + * PARAMETERS: rsdp_address - Pointer to suspected RSDP >> + * >> + * RETURN: AE_OK if rsdp_address really points to a RSDP, AE_NOT_FOUND >> + * else >> + * >> + * DESCRIPTION: Verify a physical address being a valid RSDP >> + * >> + ******************************************************************************/ >> + >> +acpi_status ACPI_INIT_FUNCTION >> +acpi_verify_root_pointer(acpi_physical_address rsdp_address) >> +{ >> + acpi_status status; >> + struct acpi_table_rsdp *rsdp; >> + >> + ACPI_FUNCTION_TRACE(acpi_verify_root_pointer); >> + >> + rsdp = acpi_os_map_memory(rsdp_address, sizeof(*rsdp)); >> + >> + if (!rsdp) >> + return_ACPI_STATUS(AE_NO_MEMORY); >> + >> + status = acpi_tb_validate_rsdp(rsdp); >> + >> + acpi_os_unmap_memory(rsdp, sizeof(*rsdp)); >> + >> + return_ACPI_STATUS(status); >> +} >> + >> +ACPI_EXPORT_SYMBOL_INIT(acpi_verify_root_pointer) >> + >> +/******************************************************************************* >> + * >> * FUNCTION: acpi_tb_scan_memory_for_rsdp >> * >> * PARAMETERS: start_address - Starting pointer for search >> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c >> index 2b77db914752..facff5c11f32 100644 >> --- a/drivers/acpi/osl.c >> +++ b/drivers/acpi/osl.c >> @@ -201,7 +201,7 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) >> return acpi_rsdp; >> #endif >> pa = acpi_arch_get_root_pointer(); >> - if (pa) >> + if (pa && acpi_verify_root_pointer(pa) == AE_OK) > > All things needed could just be done locally in this file. Okay, if you prefer it this way I can move acpi_verify_root_pointer() to osl.c. Juergen