From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752073AbbJOIVh (ORCPT ); Thu, 15 Oct 2015 04:21:37 -0400 Received: from mail.skyhub.de ([78.46.96.112]:56213 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751222AbbJOIUj (ORCPT ); Thu, 15 Oct 2015 04:20:39 -0400 From: Borislav Petkov To: LKML Cc: Andrew Morton , Andy Lutomirski , Dave Young , "H. Peter Anvin" , Ingo Molnar , jerry_hoemann@hp.com, Jiri Kosina , Joerg Roedel , Juergen Gross , Mark Salter , Thomas Gleixner , WANG Chao , x86-ml Subject: [PATCH 4/5] x86/setup/crash: Check memblock_reserve() retval Date: Thu, 15 Oct 2015 10:20:30 +0200 Message-Id: <1444897231-7906-5-git-send-email-bp@alien8.de> X-Mailer: git-send-email 2.3.5 In-Reply-To: <1444897231-7906-1-git-send-email-bp@alien8.de> References: <1444897231-7906-1-git-send-email-bp@alien8.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov memblock_reserve() can fail but the crashkernel reservation code doesn't check that and this can lead the user into believing that the crashkernel region was actually reserved. Make sure we check that return value and we exit early with a failure message in the error case. Cc: Andrew Morton Cc: Andy Lutomirski Cc: Dave Young Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: jerry_hoemann@hp.com Cc: Jiri Kosina Cc: Joerg Roedel Cc: Juergen Gross Cc: Mark Salter Cc: Thomas Gleixner Cc: WANG Chao Cc: x86-ml Signed-off-by: Borislav Petkov --- arch/x86/kernel/setup.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index d4788719a1e2..3f75297d5fd0 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -531,7 +531,11 @@ static int __init reserve_crashkernel_low(void) return -ENOMEM; } - memblock_reserve(low_base, low_size); + ret = memblock_reserve(low_base, low_size); + if (ret) { + pr_err("%s: Error reserving crashkernel low memblock.\n", __func__); + return ret; + } pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", (unsigned long)(low_size >> 20), @@ -589,7 +593,11 @@ static void __init reserve_crashkernel(void) return; } } - memblock_reserve(crash_base, crash_size); + ret = memblock_reserve(crash_base, crash_size); + if (ret) { + pr_err("%s: Error reserving crashkernel memblock.\n", __func__); + return; + } if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { memblock_free(crash_base, crash_size); -- 2.3.5