From patchwork Fri Nov 15 09:32:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245409 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 94F1C930 for ; Fri, 15 Nov 2019 09:11:37 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id F346B20733 for ; Fri, 15 Nov 2019 09:11:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F346B20733 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-17377-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21575 invoked by uid 550); 15 Nov 2019 09:11:17 -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 20344 invoked from network); 15 Nov 2019 09:11:15 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 1/6] powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and kaslr_early_init() Date: Fri, 15 Nov 2019 17:32:04 +0800 Message-ID: <20191115093209.26434-2-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected Some code refactor in kaslr_legal_offset() and kaslr_early_init(). No functional change. This is a preparation for KASLR fsl_booke64. Signed-off-by: Jason Yan Cc: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/mm/nohash/kaslr_booke.c | 40 ++++++++++++++-------------- 1 file changed, 20 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c index 4a75f2d9bf0e..07b036e98353 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -25,6 +25,7 @@ struct regions { unsigned long pa_start; unsigned long pa_end; unsigned long kernel_size; + unsigned long linear_sz; unsigned long dtb_start; unsigned long dtb_end; unsigned long initrd_start; @@ -260,11 +261,23 @@ static __init void get_cell_sizes(const void *fdt, int node, int *addr_cells, *size_cells = fdt32_to_cpu(*prop); } -static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long index, - unsigned long offset) +static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long random) { unsigned long koffset = 0; unsigned long start; + unsigned long index; + unsigned long offset; + + /* + * Decide which 64M we want to start + * Only use the low 8 bits of the random seed + */ + index = random & 0xFF; + index %= regions.linear_sz / SZ_64M; + + /* Decide offset inside 64M */ + offset = random % (SZ_64M - regions.kernel_size); + offset = round_down(offset, SZ_16K); while ((long)index >= 0) { offset = memstart_addr + index * SZ_64M + offset; @@ -289,10 +302,9 @@ static inline __init bool kaslr_disabled(void) static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size, unsigned long kernel_sz) { - unsigned long offset, random; + unsigned long random; unsigned long ram, linear_sz; u64 seed; - unsigned long index; kaslr_get_cmdline(dt_ptr); if (kaslr_disabled()) @@ -333,22 +345,12 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size regions.dtb_start = __pa(dt_ptr); regions.dtb_end = __pa(dt_ptr) + fdt_totalsize(dt_ptr); regions.kernel_size = kernel_sz; + regions.linear_sz = linear_sz; get_initrd_range(dt_ptr); get_crash_kernel(dt_ptr, ram); - /* - * Decide which 64M we want to start - * Only use the low 8 bits of the random seed - */ - index = random & 0xFF; - index %= linear_sz / SZ_64M; - - /* Decide offset inside 64M */ - offset = random % (SZ_64M - kernel_sz); - offset = round_down(offset, SZ_16K); - - return kaslr_legal_offset(dt_ptr, index, offset); + return kaslr_legal_offset(dt_ptr, random); } /* @@ -358,8 +360,6 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size */ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) { - unsigned long tlb_virt; - phys_addr_t tlb_phys; unsigned long offset; unsigned long kernel_sz; @@ -375,8 +375,8 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) is_second_reloc = 1; if (offset >= SZ_64M) { - tlb_virt = round_down(kernstart_virt_addr, SZ_64M); - tlb_phys = round_down(kernstart_addr, SZ_64M); + unsigned long tlb_virt = round_down(kernstart_virt_addr, SZ_64M); + phys_addr_t tlb_phys = round_down(kernstart_addr, SZ_64M); /* Create kernel map to relocate in */ create_kaslr_tlb_entry(1, tlb_virt, tlb_phys); From patchwork Fri Nov 15 09:32:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245411 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 CDEB0930 for ; Fri, 15 Nov 2019 09:11:45 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 3662520733 for ; Fri, 15 Nov 2019 09:11:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3662520733 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-17379-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21669 invoked by uid 550); 15 Nov 2019 09:11:19 -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 20343 invoked from network); 15 Nov 2019 09:11:15 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 2/6] powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper Date: Fri, 15 Nov 2019 17:32:05 +0800 Message-ID: <20191115093209.26434-3-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected Like the 32bit code, we introduce reloc_kernel_entry() helper to prepare for the KASLR 64bit version. And move the C declaration of this function out of CONFIG_PPC32 and use long instead of int for the parameter 'addr'. Signed-off-by: Jason Yan Cc: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/kernel/exceptions-64e.S | 13 +++++++++++++ arch/powerpc/mm/mmu_decl.h | 3 ++- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index e4076e3c072d..1b9b174bee86 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -1679,3 +1679,16 @@ _GLOBAL(setup_ehv_ivors) _GLOBAL(setup_lrat_ivor) SET_IVOR(42, 0x340) /* LRAT Error */ blr + +/* + * Return to the start of the relocated kernel and run again + * r3 - virtual address of fdt + * r4 - entry of the kernel + */ +_GLOBAL(reloc_kernel_entry) + mfmsr r7 + rlwinm r7, r7, 0, ~(MSR_IS | MSR_DS) + + mtspr SPRN_SRR0,r4 + mtspr SPRN_SRR1,r7 + rfi diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index 8e99649c24fc..3e1c85c7d10b 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -140,9 +140,10 @@ extern void adjust_total_lowmem(void); extern int switch_to_as1(void); extern void restore_to_as0(int esel, int offset, void *dt_ptr, int bootcpu); void create_kaslr_tlb_entry(int entry, unsigned long virt, phys_addr_t phys); -void reloc_kernel_entry(void *fdt, int addr); extern int is_second_reloc; #endif + +void reloc_kernel_entry(void *fdt, long addr); extern void loadcam_entry(unsigned int index); extern void loadcam_multi(int first_idx, int num, int tmp_idx); From patchwork Fri Nov 15 09:32:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245413 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 3F5171393 for ; Fri, 15 Nov 2019 09:11:54 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 9C21120723 for ; Fri, 15 Nov 2019 09:11:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C21120723 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-17378-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21635 invoked by uid 550); 15 Nov 2019 09:11:18 -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 20347 invoked from network); 15 Nov 2019 09:11:15 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 3/6] powerpc/fsl_booke/64: implement KASLR for fsl_booke64 Date: Fri, 15 Nov 2019 17:32:06 +0800 Message-ID: <20191115093209.26434-4-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected The implementation for Freescale BookE64 is similar as BookE32. One difference is that Freescale BookE64 set up a TLB mapping of 1G during booting. Another difference is that ppc64 needs the kernel to be 64K-aligned. So we can randomize the kernel in this 1G mapping and make it 64K-aligned. This can save some code to creat another TLB map at early boot. The disadvantage is that we only have about 1G/64K = 16384 slots to put the kernel in. Signed-off-by: Jason Yan Cc: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/Kconfig | 2 +- arch/powerpc/kernel/setup_64.c | 4 +++- arch/powerpc/mm/nohash/kaslr_booke.c | 29 ++++++++++++++++++++++++++-- 3 files changed, 31 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 4c4a0fcd1674..3e563a07cb67 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -553,7 +553,7 @@ config RELOCATABLE config RANDOMIZE_BASE bool "Randomize the address of the kernel image" - depends on (FSL_BOOKE && FLATMEM && PPC32) + depends on (PPC_FSL_BOOK3E && FLATMEM) depends on RELOCATABLE help Randomizes the virtual address at which the kernel image is diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index d2af4c228970..b7e4f1e92c7e 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -65,7 +65,7 @@ #include #include #include - +#include #include "setup.h" int spinning_secondaries; @@ -299,6 +299,8 @@ void __init early_setup(unsigned long dt_ptr) /* Enable early debugging if any specified (see udbg.h) */ udbg_early_init(); + kaslr_early_init(__va(dt_ptr), 0); + udbg_printf(" -> %s(), dt_ptr: 0x%lx\n", __func__, dt_ptr); /* diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c index 07b036e98353..513f4616e92a 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -265,14 +265,14 @@ static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long rando { unsigned long koffset = 0; unsigned long start; - unsigned long index; unsigned long offset; +#ifdef CONFIG_PPC32 /* * Decide which 64M we want to start * Only use the low 8 bits of the random seed */ - index = random & 0xFF; + unsigned long index = random & 0xFF; index %= regions.linear_sz / SZ_64M; /* Decide offset inside 64M */ @@ -287,6 +287,15 @@ static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long rando break; index--; } +#else + /* Decide kernel offset inside 1G */ + offset = random % (SZ_1G - regions.kernel_size); + offset = round_down(offset, SZ_64K); + + start = memstart_addr; + offset = memstart_addr + offset; + koffset = get_usable_address(dt_ptr, start, offset); +#endif if (koffset != 0) koffset -= memstart_addr; @@ -325,6 +334,7 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size else pr_warn("KASLR: No safe seed for randomizing the kernel base.\n"); +#ifdef CONFIG_PPC32 ram = min_t(phys_addr_t, __max_low_memory, size); ram = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, true); linear_sz = min_t(unsigned long, ram, SZ_512M); @@ -332,6 +342,7 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size /* If the linear size is smaller than 64M, do not randmize */ if (linear_sz < SZ_64M) return 0; +#endif /* check for a reserved-memory node and record its cell sizes */ regions.reserved_mem = fdt_path_offset(dt_ptr, "/reserved-memory"); @@ -363,6 +374,18 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) unsigned long offset; unsigned long kernel_sz; +#ifdef CONFIG_PPC64 + unsigned int *__run_at_load = (unsigned int *)(KERNELBASE + 0x5c); + + if (*__run_at_load == 1) + return; + + *__run_at_load = 1; + + /* Setup flat device-tree pointer */ + initial_boot_params = dt_ptr; +#endif + kernel_sz = (unsigned long)_end - (unsigned long)_stext; offset = kaslr_choose_location(dt_ptr, size, kernel_sz); @@ -372,6 +395,7 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) kernstart_virt_addr += offset; kernstart_addr += offset; +#ifdef CONFIG_PPC32 is_second_reloc = 1; if (offset >= SZ_64M) { @@ -381,6 +405,7 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) /* Create kernel map to relocate in */ create_kaslr_tlb_entry(1, tlb_virt, tlb_phys); } +#endif /* Copy the kernel to it's new location and run */ memcpy((void *)kernstart_virt_addr, (void *)_stext, kernel_sz); From patchwork Fri Nov 15 09:32:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245407 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 730A9930 for ; Fri, 15 Nov 2019 09:11:30 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id CFC402075E for ; Fri, 15 Nov 2019 09:11:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFC402075E 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-17376-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21511 invoked by uid 550); 15 Nov 2019 09:11:17 -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 20346 invoked from network); 15 Nov 2019 09:11:15 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 4/6] powerpc/fsl_booke/64: do not clear the BSS for the second pass Date: Fri, 15 Nov 2019 17:32:07 +0800 Message-ID: <20191115093209.26434-5-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected The BSS section has already cleared out in the first pass. No need to clear it again. This can save some time when booting with KASLR enabled. Signed-off-by: Jason Yan Cc: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/kernel/head_64.S | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index ad79fddb974d..76d8cdeddc69 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -907,6 +907,13 @@ start_here_multiplatform: bl relative_toc tovirt(r2,r2) + /* Do not clear the BSS for the second pass if randomized */ + LOAD_REG_ADDR(r3, kernstart_virt_addr) + lwz r3,0(r3) + LOAD_REG_IMMEDIATE(r4, KERNELBASE) + cmpw r3,r4 + bne 4f + /* Clear out the BSS. It may have been done in prom_init, * already but that's irrelevant since prom_init will soon * be detached from the kernel completely. Besides, we need From patchwork Fri Nov 15 09:32:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245415 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 667521393 for ; Fri, 15 Nov 2019 09:12:03 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id C59CC20723 for ; Fri, 15 Nov 2019 09:12:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C59CC20723 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-17380-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21690 invoked by uid 550); 15 Nov 2019 09:11:20 -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 20389 invoked from network); 15 Nov 2019 09:11:16 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 5/6] powerpc/fsl_booke/64: clear the original kernel if randomized Date: Fri, 15 Nov 2019 17:32:08 +0800 Message-ID: <20191115093209.26434-6-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-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: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- arch/powerpc/mm/nohash/kaslr_booke.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c index 513f4616e92a..323fe25e8e08 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -377,8 +377,10 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) #ifdef CONFIG_PPC64 unsigned int *__run_at_load = (unsigned int *)(KERNELBASE + 0x5c); - if (*__run_at_load == 1) + if (*__run_at_load == 1) { + kaslr_late_init(); return; + } *__run_at_load = 1; From patchwork Fri Nov 15 09:32:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11245417 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 451DE1393 for ; Fri, 15 Nov 2019 09:12:13 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id A3D0A20723 for ; Fri, 15 Nov 2019 09:12:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A3D0A20723 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-17381-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21963 invoked by uid 550); 15 Nov 2019 09:11:24 -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 21714 invoked from network); 15 Nov 2019 09:11:21 -0000 From: Jason Yan To: , , , , , , , , CC: , , Jason Yan Subject: [PATCH 6/6] powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst and add 64bit part Date: Fri, 15 Nov 2019 17:32:09 +0800 Message-ID: <20191115093209.26434-7-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20191115093209.26434-1-yanaijie@huawei.com> References: <20191115093209.26434-1-yanaijie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected Now we support both 32 and 64 bit KASLR for fsl booke. Add document for 64 bit part and rename kaslr-booke32.rst to kaslr-booke.rst. Signed-off-by: Jason Yan Cc: Scott Wood Cc: Diana Craciun Cc: Michael Ellerman Cc: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Nicholas Piggin Cc: Kees Cook --- .../{kaslr-booke32.rst => kaslr-booke.rst} | 35 ++++++++++++++++--- 1 file changed, 31 insertions(+), 4 deletions(-) rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%) diff --git a/Documentation/powerpc/kaslr-booke32.rst b/Documentation/powerpc/kaslr-booke.rst similarity index 59% rename from Documentation/powerpc/kaslr-booke32.rst rename to Documentation/powerpc/kaslr-booke.rst index 8b259fdfdf03..42121fed8249 100644 --- a/Documentation/powerpc/kaslr-booke32.rst +++ b/Documentation/powerpc/kaslr-booke.rst @@ -1,15 +1,18 @@ .. SPDX-License-Identifier: GPL-2.0 -=========================== -KASLR for Freescale BookE32 -=========================== +========================= +KASLR for Freescale BookE +========================= The word KASLR stands for Kernel Address Space Layout Randomization. This document tries to explain the implementation of the KASLR for -Freescale BookE32. KASLR is a security feature that deters exploit +Freescale BookE. KASLR is a security feature that deters exploit attempts relying on knowledge of the location of kernel internals. +KASLR for Freescale BookE32 +------------------------- + Since CONFIG_RELOCATABLE has already supported, what we need to do is map or copy kernel to a proper place and relocate. Freescale Book-E parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1 @@ -38,5 +41,29 @@ bit of the entropy to decide the index of the 64M zone. Then we chose a kernstart_virt_addr + +KASLR for Freescale BookE64 +--------------------------- + +The implementation for Freescale BookE64 is similar as BookE32. One +difference is that Freescale BookE64 set up a TLB mapping of 1G during +booting. Another difference is that ppc64 needs the kernel to be +64K-aligned. So we can randomize the kernel in this 1G mapping and make +it 64K-aligned. This can save some code to creat another TLB map at early +boot. The disadvantage is that we only have about 1G/64K = 16384 slots to +put the kernel in:: + + KERNELBASE + + 64K |--> kernel <--| + | | | + +--+--+--+ +--+--+--+--+--+--+--+--+--+ +--+--+ + | | | |....| | | | | | | | | |....| | | + +--+--+--+ +--+--+--+--+--+--+--+--+--+ +--+--+ + | | 1G + |-----> offset <-----| + + kernstart_virt_addr + To enable KASLR, set CONFIG_RANDOMIZE_BASE = y. If KASLR is enable and you want to disable it at runtime, add "nokaslr" to the kernel cmdline.