From patchwork Fri Sep 20 09:45:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11154137 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0177014E5 for ; Fri, 20 Sep 2019 09:27:35 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 5E5412070C for ; Fri, 20 Sep 2019 09:27:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5E5412070C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-16903-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 32395 invoked by uid 550); 20 Sep 2019 09:25:50 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 32173 invoked from network); 20 Sep 2019 09:25:46 -0000 From: Jason Yan To: , , , , , , , , CC: , , , , , , , Jason Yan Subject: [PATCH v7 08/12] powerpc/fsl_booke/kaslr: clear the original kernel if randomized Date: Fri, 20 Sep 2019 17:45:42 +0800 Message-ID: <20190920094546.44948-9-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20190920094546.44948-1-yanaijie@huawei.com> References: <20190920094546.44948-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected The original kernel still exists in the memory, clear it now. Signed-off-by: Jason Yan Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook Reviewed-by: Christophe Leroy Reviewed-by: Diana Craciun Tested-by: Diana Craciun --- arch/powerpc/mm/mmu_decl.h | 2 ++ arch/powerpc/mm/nohash/fsl_booke.c | 1 + arch/powerpc/mm/nohash/kaslr_booke.c | 11 +++++++++++ 3 files changed, 14 insertions(+) diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index a3a4937c0496..565731475a07 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -151,8 +151,10 @@ extern void loadcam_multi(int first_idx, int num, int tmp_idx); #ifdef CONFIG_RANDOMIZE_BASE void kaslr_early_init(void *dt_ptr, phys_addr_t size); +void kaslr_late_init(void); #else static inline void kaslr_early_init(void *dt_ptr, phys_addr_t size) {} +static inline void kaslr_late_init(void) {} #endif struct tlbcam { diff --git a/arch/powerpc/mm/nohash/fsl_booke.c b/arch/powerpc/mm/nohash/fsl_booke.c index 2dc27cf88add..b4eb06ceb189 100644 --- a/arch/powerpc/mm/nohash/fsl_booke.c +++ b/arch/powerpc/mm/nohash/fsl_booke.c @@ -269,6 +269,7 @@ notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start) kernstart_addr = start; if (is_second_reloc) { virt_phys_offset = PAGE_OFFSET - memstart_addr; + kaslr_late_init(); return; } diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c index 7b238fc2c8a9..aa1b60c782e7 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -381,3 +381,14 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) reloc_kernel_entry(dt_ptr, kernstart_virt_addr); } + +void __init kaslr_late_init(void) +{ + /* If randomized, clear the original kernel */ + if (kernstart_virt_addr != KERNELBASE) { + unsigned long kernel_sz; + + kernel_sz = (unsigned long)_end - kernstart_virt_addr; + memzero_explicit((void *)KERNELBASE, kernel_sz); + } +}