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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 60917C5B579 for ; Fri, 28 Jun 2019 19:17:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 465E5215EA for ; Fri, 28 Jun 2019 19:17:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727090AbfF1TRk (ORCPT ); Fri, 28 Jun 2019 15:17:40 -0400 Received: from outgoing-stata.csail.mit.edu ([128.30.2.210]:48697 "EHLO outgoing-stata.csail.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727037AbfF1TRj (ORCPT ); Fri, 28 Jun 2019 15:17:39 -0400 X-Greylist: delayed 2137 seconds by postgrey-1.27 at vger.kernel.org; Fri, 28 Jun 2019 15:17:38 EDT Received: from [4.30.142.84] (helo=[127.0.1.1]) by outgoing-stata.csail.mit.edu with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.82) (envelope-from ) id 1hgvp9-000Swq-Hb; Fri, 28 Jun 2019 14:42:15 -0400 Subject: [4.19.y PATCH 1/3] efi/x86/Add missing error handling to old_memmap 1:1 mapping code From: "Srivatsa S. Bhat" To: stable@vger.kernel.org, gregkh@linuxfoundation.org Cc: Gen Zhang , Ard Biesheuvel , Linus Torvalds , Peter Zijlstra , Rob Bradford , Thomas Gleixner , linux-efi@vger.kernel.org, Ingo Molnar , akaher@vmware.com, srinidhir@vmware.com, bvikas@vmware.com, amakhalov@vmware.com, srivatsab@vmware.com, srivatsa@csail.mit.edu Date: Fri, 28 Jun 2019 11:42:13 -0700 Message-ID: <156174732219.34985.6679541271840078416.stgit@srivatsa-ubuntu> In-Reply-To: <156174726746.34985.1890238158382638220.stgit@srivatsa-ubuntu> References: <156174726746.34985.1890238158382638220.stgit@srivatsa-ubuntu> User-Agent: StGit/0.18 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Gen Zhang commit 4e78921ba4dd0aca1cc89168f45039add4183f8e upstream. The old_memmap flow in efi_call_phys_prolog() performs numerous memory allocations, and either does not check for failure at all, or it does but fails to propagate it back to the caller, which may end up calling into the firmware with an incomplete 1:1 mapping. So let's fix this by returning NULL from efi_call_phys_prolog() on memory allocation failures only, and by handling this condition in the caller. Also, clean up any half baked sets of page tables that we may have created before returning with a NULL return value. Note that any failure at this level will trigger a panic() two levels up, so none of this makes a huge difference, but it is a nice cleanup nonetheless. [ardb: update commit log, add efi_call_phys_epilog() call on error path] Signed-off-by: Gen Zhang Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rob Bradford Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20190525112559.7917-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Srivatsa S. Bhat (VMware) --- arch/x86/platform/efi/efi.c | 2 ++ arch/x86/platform/efi/efi_64.c | 9 ++++++--- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 9061bab..353019d 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -86,6 +86,8 @@ static efi_status_t __init phys_efi_set_virtual_address_map( pgd_t *save_pgd; save_pgd = efi_call_phys_prolog(); + if (!save_pgd) + return EFI_ABORTED; /* Disable interrupts around EFI calls: */ local_irq_save(flags); diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index ee5d08f..dfc809b 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -84,13 +84,15 @@ pgd_t * __init efi_call_phys_prolog(void) if (!efi_enabled(EFI_OLD_MEMMAP)) { efi_switch_mm(&efi_mm); - return NULL; + return efi_mm.pgd; } early_code_mapping_set_exec(1); n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE); save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL); + if (!save_pgd) + return NULL; /* * Build 1:1 identity mapping for efi=old_map usage. Note that @@ -138,10 +140,11 @@ pgd_t * __init efi_call_phys_prolog(void) pgd_offset_k(pgd * PGDIR_SIZE)->pgd &= ~_PAGE_NX; } -out: __flush_tlb_all(); - return save_pgd; +out: + efi_call_phys_epilog(save_pgd); + return NULL; } void __init efi_call_phys_epilog(pgd_t *save_pgd)