From patchwork Wed Feb 5 02:55:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365691 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 6D61813A4 for ; Wed, 5 Feb 2020 02:57:00 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 649632082E for ; Wed, 5 Feb 2020 02:56:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 649632082E 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-17662-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 3927 invoked by uid 550); 5 Feb 2020 02:56:51 -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 3868 invoked from network); 5 Feb 2020 02:56:50 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 1/6] powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and kaslr_early_init() Date: Wed, 5 Feb 2020 10:55:22 +0800 Message-ID: <20200205025527.28640-2-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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 Wed Feb 5 02:55:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365695 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 EDADB14E3 for ; Wed, 5 Feb 2020 02:57:14 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 60CD4214AF for ; Wed, 5 Feb 2020 02:57:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 60CD4214AF 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-17664-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 4073 invoked by uid 550); 5 Feb 2020 02:56:54 -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 3865 invoked from network); 5 Feb 2020 02:56:50 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 2/6] powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper Date: Wed, 5 Feb 2020 10:55:23 +0800 Message-ID: <20200205025527.28640-3-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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 Wed Feb 5 02:55:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365693 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 DA64713A4 for ; Wed, 5 Feb 2020 02:57:07 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 23C3D2082E for ; Wed, 5 Feb 2020 02:57:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 23C3D2082E 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-17663-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 4045 invoked by uid 550); 5 Feb 2020 02:56:53 -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 3869 invoked from network); 5 Feb 2020 02:56:51 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 3/6] powerpc/fsl_booke/64: implement KASLR for fsl_booke64 Date: Wed, 5 Feb 2020 10:55:24 +0800 Message-ID: <20200205025527.28640-4-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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. To support secondary cpu boot up, a variable __kaslr_offset was added in first_256B section. This can help secondary cpu get the kaslr offset before the 1:1 mapping has been setup. 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 Reported-by: kbuild test robot --- arch/powerpc/Kconfig | 2 +- arch/powerpc/kernel/exceptions-64e.S | 8 +++++++ arch/powerpc/kernel/head_64.S | 7 ++++++ arch/powerpc/kernel/setup_64.c | 4 +++- arch/powerpc/mm/nohash/kaslr_booke.c | 33 +++++++++++++++++++++++++--- 5 files changed, 49 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index c150a9d49343..754aeb96bb1c 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -568,7 +568,7 @@ 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/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 1b9b174bee86..121daeaf573d 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -1378,6 +1378,7 @@ skpinv: addi r6,r6,1 /* Increment */ 1: mflr r6 addi r6,r6,(2f - 1b) tovirt(r6,r6) + add r6,r6,r19 lis r7,MSR_KERNEL@h ori r7,r7,MSR_KERNEL@l mtspr SPRN_SRR0,r6 @@ -1400,6 +1401,7 @@ skpinv: addi r6,r6,1 /* Increment */ /* We translate LR and return */ tovirt(r8,r8) + add r8,r8,r19 mtlr r8 blr @@ -1528,6 +1530,7 @@ a2_tlbinit_code_end: */ _GLOBAL(start_initialization_book3e) mflr r28 + li r19, 0 /* First, we need to setup some initial TLBs to map the kernel * text, data and bss at PAGE_OFFSET. We don't have a real mode @@ -1570,6 +1573,10 @@ _GLOBAL(book3e_secondary_core_init) cmplwi r4,0 bne 2f + LOAD_REG_ADDR_PIC(r19, __kaslr_offset) + lwz r19,0(r19) + rlwinm r19,r19,0,0,5 + /* Setup TLB for this core */ bl initial_tlb_book3e @@ -1602,6 +1609,7 @@ _GLOBAL(book3e_secondary_core_init) lis r3,PAGE_OFFSET@highest sldi r3,r3,32 or r28,r28,r3 + add r28,r28,r19 1: mtlr r28 blr diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index ad79fddb974d..b4ececc4323d 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -104,6 +104,13 @@ __secondary_hold_acknowledge: .8byte 0x0 #ifdef CONFIG_RELOCATABLE +#ifdef CONFIG_PPC_BOOK3E + . = 0x58 + .globl __kaslr_offset +__kaslr_offset: +DEFINE_FIXED_SYMBOL(__kaslr_offset) + .long 0 +#endif /* This flag is set to 1 by a loader if the kernel should run * at the loaded address instead of the linked address. This * is used by kexec-tools to keep the the kdump kernel in the diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 6104917a282d..a16b970a8d1a 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -66,7 +66,7 @@ #include #include #include - +#include #include "setup.h" int spinning_secondaries; @@ -300,6 +300,8 @@ 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..c6f5c1db1394 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -231,7 +231,7 @@ static __init unsigned long get_usable_address(const void *fdt, unsigned long pa; unsigned long pa_end; - for (pa = offset; (long)pa > (long)start; pa -= SZ_16K) { + for (pa = offset; (long)pa > (long)start; pa -= SZ_64K) { pa_end = pa + regions.kernel_size; if (overlaps_region(fdt, pa, pa_end)) continue; @@ -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 +374,17 @@ 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 *__kaslr_offset = (unsigned int *)(KERNELBASE + 0x58); + unsigned int *__run_at_load = (unsigned int *)(KERNELBASE + 0x5c); + + if (*__run_at_load == 1) + return; + + /* 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 +394,7 @@ 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 +404,10 @@ 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); } +#else + *__kaslr_offset = kernstart_virt_addr - KERNELBASE; + *__run_at_load = 1; +#endif /* Copy the kernel to it's new location and run */ memcpy((void *)kernstart_virt_addr, (void *)_stext, kernel_sz); From patchwork Wed Feb 5 02:55:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365701 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 EDFE413A4 for ; Wed, 5 Feb 2020 02:57:37 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 612932082E for ; Wed, 5 Feb 2020 02:57:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 612932082E 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-17666-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 5160 invoked by uid 550); 5 Feb 2020 02:56:56 -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 3867 invoked from network); 5 Feb 2020 02:56:50 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 4/6] powerpc/fsl_booke/64: do not clear the BSS for the second pass Date: Wed, 5 Feb 2020 10:55:25 +0800 Message-ID: <20200205025527.28640-5-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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 b4ececc4323d..9ae7fd8bbf7c 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -914,6 +914,13 @@ 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 Wed Feb 5 02:55:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365699 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 DC9AC14E3 for ; Wed, 5 Feb 2020 02:57:29 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 4F70F2082E for ; Wed, 5 Feb 2020 02:57:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4F70F2082E 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-17667-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 5182 invoked by uid 550); 5 Feb 2020 02:56:56 -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 4050 invoked from network); 5 Feb 2020 02:56:53 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 5/6] powerpc/fsl_booke/64: clear the original kernel if randomized Date: Wed, 5 Feb 2020 10:55:26 +0800 Message-ID: <20200205025527.28640-6-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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 c6f5c1db1394..ed1277059368 100644 --- a/arch/powerpc/mm/nohash/kaslr_booke.c +++ b/arch/powerpc/mm/nohash/kaslr_booke.c @@ -378,8 +378,10 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size) unsigned int *__kaslr_offset = (unsigned int *)(KERNELBASE + 0x58); unsigned int *__run_at_load = (unsigned int *)(KERNELBASE + 0x5c); - if (*__run_at_load == 1) + if (*__run_at_load == 1) { + kaslr_late_init(); return; + } /* Setup flat device-tree pointer */ initial_boot_params = dt_ptr; From patchwork Wed Feb 5 02:55:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Yan X-Patchwork-Id: 11365703 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 B847214E3 for ; Wed, 5 Feb 2020 02:57:46 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 2C0012082E for ; Wed, 5 Feb 2020 02:57:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C0012082E 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-17668-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 5235 invoked by uid 550); 5 Feb 2020 02:56:57 -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 4051 invoked from network); 5 Feb 2020 02:56:53 -0000 From: Jason Yan To: , , , , , , , , , CC: , , Jason Yan Subject: [PATCH v2 6/6] powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst and add 64bit part Date: Wed, 5 Feb 2020 10:55:27 +0800 Message-ID: <20200205025527.28640-7-yanaijie@huawei.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200205025527.28640-1-yanaijie@huawei.com> References: <20200205025527.28640-1-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.