From patchwork Fri Aug 9 10:07:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11086159 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6264113B1 for ; Fri, 9 Aug 2019 09:54:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 51DD028C2B for ; Fri, 9 Aug 2019 09:54:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4437A28C5E; Fri, 9 Aug 2019 09:54:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 566F228C5C for ; Fri, 9 Aug 2019 09:54:37 +0000 (UTC) Received: (qmail 15489 invoked by uid 550); 9 Aug 2019 09:52:31 -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 15388 invoked from network); 9 Aug 2019 09:52:30 -0000 From: Jason Yan To: , , , , , , , , CC: , , , , , , , Jason Yan Subject: [PATCH v6 08/12] powerpc/fsl_booke/kaslr: clear the original kernel if randomized Date: Fri, 9 Aug 2019 18:07:56 +0800 Message-ID: <20190809100800.5426-9-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20190809100800.5426-1-yanaijie@huawei.com> References: <20190809100800.5426-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected X-Virus-Scanned: ClamAV using ClamSMTP 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/kernel/kaslr_booke.c | 11 +++++++++++ arch/powerpc/mm/mmu_decl.h | 2 ++ arch/powerpc/mm/nohash/fsl_booke.c | 1 + 3 files changed, 14 insertions(+) diff --git a/arch/powerpc/kernel/kaslr_booke.c b/arch/powerpc/kernel/kaslr_booke.c index 51a0b3749724..9a360b6124ed 100644 --- a/arch/powerpc/kernel/kaslr_booke.c +++ b/arch/powerpc/kernel/kaslr_booke.c @@ -373,3 +373,14 @@ 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); + } +} diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index 213997d69729..64b2ac8a5343 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; }