| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <76353fc0-f734-db47-0d0c-f0f379763aa0@ghiti.fr>
Date: Thu, 15 Apr 2021 00:54:25 -0400
From: Alex Ghiti <alex@...ti.fr>
To: Palmer Dabbelt <palmer@...belt.com>
Cc: corbet@....net, Paul Walmsley <paul.walmsley@...ive.com>,
aou@...s.berkeley.edu, Arnd Bergmann <arnd@...db.de>,
aryabinin@...tuozzo.com, glider@...gle.com, dvyukov@...gle.com,
linux-doc@...r.kernel.org, linux-riscv@...ts.infradead.org,
linux-kernel@...r.kernel.org, kasan-dev@...glegroups.com,
linux-arch@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH v5 1/3] riscv: Move kernel mapping outside of linear
mapping
Le 4/15/21 à 12:20 AM, Palmer Dabbelt a écrit :
> On Sun, 11 Apr 2021 09:41:44 PDT (-0700), alex@...ti.fr wrote:
>> This is a preparatory patch for relocatable kernel and sv48 support.
>>
>> The kernel used to be linked at PAGE_OFFSET address therefore we could
>> use
>> the linear mapping for the kernel mapping. But the relocated kernel base
>> address will be different from PAGE_OFFSET and since in the linear
>> mapping,
>> two different virtual addresses cannot point to the same physical
>> address,
>> the kernel mapping needs to lie outside the linear mapping so that we
>> don't
>> have to copy it at the same physical offset.
>>
>> The kernel mapping is moved to the last 2GB of the address space, BPF
>> is now always after the kernel and modules use the 2GB memory range right
>> before the kernel, so BPF and modules regions do not overlap. KASLR
>> implementation will simply have to move the kernel in the last 2GB range
>> and just take care of leaving enough space for BPF.
>>
>> In addition, by moving the kernel to the end of the address space, both
>> sv39 and sv48 kernels will be exactly the same without needing to be
>> relocated at runtime.
>>
>> Suggested-by: Arnd Bergmann <arnd@...db.de>
>> Signed-off-by: Alexandre Ghiti <alex@...ti.fr>
>> ---
>> arch/riscv/boot/loader.lds.S | 3 +-
>> arch/riscv/include/asm/page.h | 17 +++++-
>> arch/riscv/include/asm/pgtable.h | 37 ++++++++----
>> arch/riscv/include/asm/set_memory.h | 1 +
>> arch/riscv/kernel/head.S | 3 +-
>> arch/riscv/kernel/module.c | 6 +-
>> arch/riscv/kernel/setup.c | 5 ++
>> arch/riscv/kernel/vmlinux.lds.S | 3 +-
>> arch/riscv/mm/fault.c | 13 +++++
>> arch/riscv/mm/init.c | 87 ++++++++++++++++++++++-------
>> arch/riscv/mm/kasan_init.c | 9 +++
>> arch/riscv/mm/physaddr.c | 2 +-
>> 12 files changed, 146 insertions(+), 40 deletions(-)
>>
>> diff --git a/arch/riscv/boot/loader.lds.S b/arch/riscv/boot/loader.lds.S
>> index 47a5003c2e28..62d94696a19c 100644
>> --- a/arch/riscv/boot/loader.lds.S
>> +++ b/arch/riscv/boot/loader.lds.S
>> @@ -1,13 +1,14 @@
>> /* SPDX-License-Identifier: GPL-2.0 */
>>
>> #include <asm/page.h>
>> +#include <asm/pgtable.h>
>>
>> OUTPUT_ARCH(riscv)
>> ENTRY(_start)
>>
>> SECTIONS
>> {
>> - . = PAGE_OFFSET;
>> + . = KERNEL_LINK_ADDR;
>>
>> .payload : {
>> *(.payload)
>> diff --git a/arch/riscv/include/asm/page.h
>> b/arch/riscv/include/asm/page.h
>> index adc9d26f3d75..22cfb2be60dc 100644
>> --- a/arch/riscv/include/asm/page.h
>> +++ b/arch/riscv/include/asm/page.h
>> @@ -90,15 +90,28 @@ typedef struct page *pgtable_t;
>>
>> #ifdef CONFIG_MMU
>> extern unsigned long va_pa_offset;
>> +extern unsigned long va_kernel_pa_offset;
>> extern unsigned long pfn_base;
>> #define ARCH_PFN_OFFSET (pfn_base)
>> #else
>> #define va_pa_offset 0
>> +#define va_kernel_pa_offset 0
>> #define ARCH_PFN_OFFSET (PAGE_OFFSET >> PAGE_SHIFT)
>> #endif /* CONFIG_MMU */
>>
>> -#define __pa_to_va_nodebug(x) ((void *)((unsigned long) (x) +
>> va_pa_offset))
>> -#define __va_to_pa_nodebug(x) ((unsigned long)(x) - va_pa_offset)
>> +extern unsigned long kernel_virt_addr;
>> +
>> +#define linear_mapping_pa_to_va(x) ((void *)((unsigned long)(x) +
>> va_pa_offset))
>> +#define kernel_mapping_pa_to_va(x) ((void *)((unsigned long)(x) +
>> va_kernel_pa_offset))
>> +#define __pa_to_va_nodebug(x) linear_mapping_pa_to_va(x)
>> +
>> +#define linear_mapping_va_to_pa(x) ((unsigned long)(x) -
>> va_pa_offset)
>> +#define kernel_mapping_va_to_pa(x) ((unsigned long)(x) -
>> va_kernel_pa_offset)
>> +#define __va_to_pa_nodebug(x) ({ \
>> + unsigned long _x = x; \
>> + (_x < kernel_virt_addr) ? \
>> + linear_mapping_va_to_pa(_x) : kernel_mapping_va_to_pa(_x); \
>> + })
>>
>> #ifdef CONFIG_DEBUG_VIRTUAL
>> extern phys_addr_t __virt_to_phys(unsigned long x);
>> diff --git a/arch/riscv/include/asm/pgtable.h
>> b/arch/riscv/include/asm/pgtable.h
>> index ebf817c1bdf4..80e63a93e903 100644
>> --- a/arch/riscv/include/asm/pgtable.h
>> +++ b/arch/riscv/include/asm/pgtable.h
>> @@ -11,23 +11,30 @@
>>
>> #include <asm/pgtable-bits.h>
>>
>> -#ifndef __ASSEMBLY__
>> -
>> -/* Page Upper Directory not used in RISC-V */
>> -#include <asm-generic/pgtable-nopud.h>
>> -#include <asm/page.h>
>> -#include <asm/tlbflush.h>
>> -#include <linux/mm_types.h>
>> +#ifndef CONFIG_MMU
>> +#define KERNEL_LINK_ADDR PAGE_OFFSET
>> +#else
>>
>> -#ifdef CONFIG_MMU
>> +#define ADDRESS_SPACE_END (UL(-1))
>> +/*
>> + * Leave 2GB for kernel and BPF at the end of the address space
>> + */
>> +#define KERNEL_LINK_ADDR (ADDRESS_SPACE_END - SZ_2G + 1)
>>
>> #define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1)
>> #define VMALLOC_END (PAGE_OFFSET - 1)
>> #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE)
>>
>> +/* KASLR should leave at least 128MB for BPF after the kernel */
>> #define BPF_JIT_REGION_SIZE (SZ_128M)
>> -#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
>> -#define BPF_JIT_REGION_END (VMALLOC_END)
>> +#define BPF_JIT_REGION_START PFN_ALIGN((unsigned long)&_end)
>> +#define BPF_JIT_REGION_END (BPF_JIT_REGION_START +
>> BPF_JIT_REGION_SIZE)
>> +
>> +/* Modules always live before the kernel */
>> +#ifdef CONFIG_64BIT
>> +#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G)
>> +#define MODULES_END (PFN_ALIGN((unsigned long)&_start))
>> +#endif
>>
>> /*
>> * Roughly size the vmemmap space to be large enough to fit enough
>> @@ -57,9 +64,16 @@
>> #define FIXADDR_SIZE PGDIR_SIZE
>> #endif
>> #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
>> -
>> #endif
>>
>> +#ifndef __ASSEMBLY__
>> +
>> +/* Page Upper Directory not used in RISC-V */
>> +#include <asm-generic/pgtable-nopud.h>
>> +#include <asm/page.h>
>> +#include <asm/tlbflush.h>
>> +#include <linux/mm_types.h>
>> +
>> #ifdef CONFIG_64BIT
>> #include <asm/pgtable-64.h>
>> #else
>> @@ -484,6 +498,7 @@ static inline int ptep_clear_flush_young(struct
>> vm_area_struct *vma,
>>
>> #define kern_addr_valid(addr) (1) /* FIXME */
>>
>> +extern char _start[];
>> extern void *dtb_early_va;
>> extern uintptr_t dtb_early_pa;
>> void setup_bootmem(void);
>> diff --git a/arch/riscv/include/asm/set_memory.h
>> b/arch/riscv/include/asm/set_memory.h
>> index 6887b3d9f371..a9c56776fa0e 100644
>> --- a/arch/riscv/include/asm/set_memory.h
>> +++ b/arch/riscv/include/asm/set_memory.h
>> @@ -17,6 +17,7 @@ int set_memory_x(unsigned long addr, int numpages);
>> int set_memory_nx(unsigned long addr, int numpages);
>> int set_memory_rw_nx(unsigned long addr, int numpages);
>> void protect_kernel_text_data(void);
>> +void protect_kernel_linear_mapping_text_rodata(void);
>> #else
>> static inline int set_memory_ro(unsigned long addr, int numpages) {
>> return 0; }
>> static inline int set_memory_rw(unsigned long addr, int numpages) {
>> return 0; }
>> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>> index f5a9bad86e58..6cb05f22e52a 100644
>> --- a/arch/riscv/kernel/head.S
>> +++ b/arch/riscv/kernel/head.S
>> @@ -69,7 +69,8 @@ pe_head_start:
>> #ifdef CONFIG_MMU
>> relocate:
>> /* Relocate return address */
>> - li a1, PAGE_OFFSET
>> + la a1, kernel_virt_addr
>> + REG_L a1, 0(a1)
>> la a2, _start
>> sub a1, a1, a2
>> add ra, ra, a1
>> diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
>> index 104fba889cf7..ce153771e5e9 100644
>> --- a/arch/riscv/kernel/module.c
>> +++ b/arch/riscv/kernel/module.c
>> @@ -408,12 +408,10 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const
>> char *strtab,
>> }
>>
>> #if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
>> -#define VMALLOC_MODULE_START \
>> - max(PFN_ALIGN((unsigned long)&_end - SZ_2G), VMALLOC_START)
>> void *module_alloc(unsigned long size)
>> {
>> - return __vmalloc_node_range(size, 1, VMALLOC_MODULE_START,
>> - VMALLOC_END, GFP_KERNEL,
>> + return __vmalloc_node_range(size, 1, MODULES_VADDR,
>> + MODULES_END, GFP_KERNEL,
>> PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
>> __builtin_return_address(0));
>> }
>> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
>> index e85bacff1b50..30e4af0fd50c 100644
>> --- a/arch/riscv/kernel/setup.c
>> +++ b/arch/riscv/kernel/setup.c
>> @@ -265,6 +265,11 @@ void __init setup_arch(char **cmdline_p)
>>
>> if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
>> protect_kernel_text_data();
>> +
>> +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU)
>> + protect_kernel_linear_mapping_text_rodata();
>> +#endif
>> +
>> #ifdef CONFIG_SWIOTLB
>> swiotlb_init(1);
>> #endif
>> diff --git a/arch/riscv/kernel/vmlinux.lds.S
>> b/arch/riscv/kernel/vmlinux.lds.S
>> index de03cb22d0e9..0726c05e0336 100644
>> --- a/arch/riscv/kernel/vmlinux.lds.S
>> +++ b/arch/riscv/kernel/vmlinux.lds.S
>> @@ -4,7 +4,8 @@
>> * Copyright (C) 2017 SiFive
>> */
>>
>> -#define LOAD_OFFSET PAGE_OFFSET
>> +#include <asm/pgtable.h>
>> +#define LOAD_OFFSET KERNEL_LINK_ADDR
>> #include <asm/vmlinux.lds.h>
>> #include <asm/page.h>
>> #include <asm/cache.h>
>> diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
>> index 8f17519208c7..1b14d523a95c 100644
>> --- a/arch/riscv/mm/fault.c
>> +++ b/arch/riscv/mm/fault.c
>> @@ -231,6 +231,19 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
>> return;
>> }
>>
>> +#ifdef CONFIG_64BIT
>> + /*
>> + * Modules in 64bit kernels lie in their own virtual region which
>> is not
>> + * in the vmalloc region, but dealing with page faults in this
>> region
>> + * or the vmalloc region amounts to doing the same thing:
>> checking that
>> + * the mapping exists in init_mm.pgd and updating user page
>> table, so
>> + * just use vmalloc_fault.
>> + */
>> + if (unlikely(addr >= MODULES_VADDR && addr < MODULES_END)) {
>> + vmalloc_fault(regs, code, addr);
>> + return;
>> + }
>> +#endif
>> /* Enable interrupts if they were enabled in the parent context. */
>> if (likely(regs->status & SR_PIE))
>> local_irq_enable();
>> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
>> index 7f5036fbee8c..093f3a96ecfc 100644
>> --- a/arch/riscv/mm/init.c
>> +++ b/arch/riscv/mm/init.c
>> @@ -25,6 +25,9 @@
>>
>> #include "../kernel/head.h"
>>
>> +unsigned long kernel_virt_addr = KERNEL_LINK_ADDR;
>> +EXPORT_SYMBOL(kernel_virt_addr);
>> +
>> unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
>> __page_aligned_bss;
>> EXPORT_SYMBOL(empty_zero_page);
>> @@ -88,6 +91,8 @@ static void print_vm_layout(void)
>> (unsigned long)VMALLOC_END);
>> print_mlm("lowmem", (unsigned long)PAGE_OFFSET,
>> (unsigned long)high_memory);
>> + print_mlm("kernel", (unsigned long)KERNEL_LINK_ADDR,
>> + (unsigned long)ADDRESS_SPACE_END);
>> }
>> #else
>> static void print_vm_layout(void) { }
>> @@ -116,8 +121,13 @@ void __init setup_bootmem(void)
>> /* The maximal physical memory size is -PAGE_OFFSET. */
>> memblock_enforce_memory_limit(-PAGE_OFFSET);
>>
>> - /* Reserve from the start of the kernel to the end of the kernel */
>> - memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
>> + /*
>> + * Reserve from the start of the kernel to the end of the kernel
>> + * and make sure we align the reservation on PMD_SIZE since we will
>> + * map the kernel in the linear mapping as read-only: we do not want
>> + * any allocation to happen between _end and the next pmd aligned
>> page.
>> + */
>> + memblock_reserve(vmlinux_start, (vmlinux_end - vmlinux_start +
>> PMD_SIZE - 1) & PMD_MASK);
>>
>> /*
>> * memblock allocator is not aware of the fact that last 4K bytes of
>> @@ -152,8 +162,12 @@ void __init setup_bootmem(void)
>> #ifdef CONFIG_MMU
>> static struct pt_alloc_ops pt_ops;
>>
>> +/* Offset between linear mapping virtual address and kernel load
>> address */
>> unsigned long va_pa_offset;
>> EXPORT_SYMBOL(va_pa_offset);
>> +/* Offset between kernel mapping virtual address and kernel load
>> address */
>> +unsigned long va_kernel_pa_offset;
>> +EXPORT_SYMBOL(va_kernel_pa_offset);
>> unsigned long pfn_base;
>> EXPORT_SYMBOL(pfn_base);
>>
>> @@ -257,7 +271,7 @@ static pmd_t *get_pmd_virt_late(phys_addr_t pa)
>>
>> static phys_addr_t __init alloc_pmd_early(uintptr_t va)
>> {
>> - BUG_ON((va - PAGE_OFFSET) >> PGDIR_SHIFT);
>> + BUG_ON((va - kernel_virt_addr) >> PGDIR_SHIFT);
>>
>> return (uintptr_t)early_pmd;
>> }
>> @@ -372,17 +386,32 @@ static uintptr_t __init
>> best_map_size(phys_addr_t base, phys_addr_t size)
>> #error "setup_vm() is called from head.S before relocate so it should
>> not use absolute addressing."
>> #endif
>>
>> +uintptr_t load_pa, load_sz;
>> +
>> +static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t
>> map_size)
>> +{
>> + uintptr_t va, end_va;
>> +
>> + end_va = kernel_virt_addr + load_sz;
>> + for (va = kernel_virt_addr; va < end_va; va += map_size)
>> + create_pgd_mapping(pgdir, va,
>> + load_pa + (va - kernel_virt_addr),
>> + map_size, PAGE_KERNEL_EXEC);
>> +}
>> +
>> asmlinkage void __init setup_vm(uintptr_t dtb_pa)
>> {
>> - uintptr_t va, pa, end_va;
>> - uintptr_t load_pa = (uintptr_t)(&_start);
>> - uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
>> + uintptr_t pa;
>> uintptr_t map_size;
>> #ifndef __PAGETABLE_PMD_FOLDED
>> pmd_t fix_bmap_spmd, fix_bmap_epmd;
>> #endif
>> + load_pa = (uintptr_t)(&_start);
>> + load_sz = (uintptr_t)(&_end) - load_pa;
>>
>> va_pa_offset = PAGE_OFFSET - load_pa;
>> + va_kernel_pa_offset = kernel_virt_addr - load_pa;
>> +
>> pfn_base = PFN_DOWN(load_pa);
>>
>> /*
>> @@ -410,26 +439,22 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
>> create_pmd_mapping(fixmap_pmd, FIXADDR_START,
>> (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
>> /* Setup trampoline PGD and PMD */
>> - create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
>> + create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr,
>> (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
>> - create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
>> + create_pmd_mapping(trampoline_pmd, kernel_virt_addr,
>> load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
>> #else
>> /* Setup trampoline PGD */
>> - create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
>> + create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr,
>> load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
>> #endif
>>
>> /*
>> - * Setup early PGD covering entire kernel which will allows
>> + * Setup early PGD covering entire kernel which will allow
>> * us to reach paging_init(). We map all memory banks later
>> * in setup_vm_final() below.
>> */
>> - end_va = PAGE_OFFSET + load_sz;
>> - for (va = PAGE_OFFSET; va < end_va; va += map_size)
>> - create_pgd_mapping(early_pg_dir, va,
>> - load_pa + (va - PAGE_OFFSET),
>> - map_size, PAGE_KERNEL_EXEC);
>> + create_kernel_page_table(early_pg_dir, map_size);
>>
>> #ifndef __PAGETABLE_PMD_FOLDED
>> /* Setup early PMD for DTB */
>> @@ -444,7 +469,12 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
>> pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
>> dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE -
>> 1));
>> #else /* CONFIG_BUILTIN_DTB */
>> - dtb_early_va = __va(dtb_pa);
>> + /*
>> + * __va can't be used since it would return a linear mapping address
>> + * whereas dtb_early_va will be used before setup_vm_final installs
>> + * the linear mapping.
>> + */
>> + dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
>> #endif /* CONFIG_BUILTIN_DTB */
>> #else
>> #ifndef CONFIG_BUILTIN_DTB
>> @@ -456,7 +486,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
>> pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
>> dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE
>> - 1));
>> #else /* CONFIG_BUILTIN_DTB */
>> - dtb_early_va = __va(dtb_pa);
>> + dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
>> #endif /* CONFIG_BUILTIN_DTB */
>> #endif
>> dtb_early_pa = dtb_pa;
>> @@ -492,6 +522,22 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
>> #endif
>> }
>>
>> +#ifdef CONFIG_64BIT
>> +void protect_kernel_linear_mapping_text_rodata(void)
>> +{
>> + unsigned long text_start = (unsigned long)lm_alias(_start);
>> + unsigned long init_text_start = (unsigned
>> long)lm_alias(__init_text_begin);
>> + unsigned long rodata_start = (unsigned
>> long)lm_alias(__start_rodata);
>> + unsigned long data_start = (unsigned long)lm_alias(_data);
>> +
>> + set_memory_ro(text_start, (init_text_start - text_start) >>
>> PAGE_SHIFT);
>> + set_memory_nx(text_start, (init_text_start - text_start) >>
>> PAGE_SHIFT);
>> +
>> + set_memory_ro(rodata_start, (data_start - rodata_start) >>
>> PAGE_SHIFT);
>> + set_memory_nx(rodata_start, (data_start - rodata_start) >>
>> PAGE_SHIFT);
>> +}
>> +#endif
>> +
>> static void __init setup_vm_final(void)
>> {
>> uintptr_t va, map_size;
>> @@ -513,7 +559,7 @@ static void __init setup_vm_final(void)
>> __pa_symbol(fixmap_pgd_next),
>> PGDIR_SIZE, PAGE_TABLE);
>>
>> - /* Map all memory banks */
>> + /* Map all memory banks in the linear mapping */
>> for_each_mem_range(i, &start, &end) {
>> if (start >= end)
>> break;
>> @@ -525,10 +571,13 @@ static void __init setup_vm_final(void)
>> for (pa = start; pa < end; pa += map_size) {
>> va = (uintptr_t)__va(pa);
>> create_pgd_mapping(swapper_pg_dir, va, pa,
>> - map_size, PAGE_KERNEL_EXEC);
>> + map_size, PAGE_KERNEL);
>> }
>> }
>>
>> + /* Map the kernel */
>> + create_kernel_page_table(swapper_pg_dir, PMD_SIZE);
>> +
>> /* Clear fixmap PTE and PMD mappings */
>> clear_fixmap(FIX_PTE);
>> clear_fixmap(FIX_PMD);
>> diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c
>> index 2c39f0386673..28f4d52cf17e 100644
>> --- a/arch/riscv/mm/kasan_init.c
>> +++ b/arch/riscv/mm/kasan_init.c
>> @@ -171,6 +171,10 @@ void __init kasan_init(void)
>> phys_addr_t _start, _end;
>> u64 i;
>>
>> + /*
>> + * Populate all kernel virtual address space with
>> kasan_early_shadow_page
>> + * except for the linear mapping and the modules/kernel/BPF mapping.
>> + */
>> kasan_populate_early_shadow((void *)KASAN_SHADOW_START,
>> (void *)kasan_mem_to_shadow((void *)
>> VMEMMAP_END));
>> @@ -183,6 +187,7 @@ void __init kasan_init(void)
>> (void *)kasan_mem_to_shadow((void *)VMALLOC_START),
>> (void *)kasan_mem_to_shadow((void *)VMALLOC_END));
>>
>> + /* Populate the linear mapping */
>> for_each_mem_range(i, &_start, &_end) {
>> void *start = (void *)__va(_start);
>> void *end = (void *)__va(_end);
>> @@ -193,6 +198,10 @@ void __init kasan_init(void)
>> kasan_populate(kasan_mem_to_shadow(start),
>> kasan_mem_to_shadow(end));
>> };
>>
>> + /* Populate kernel, BPF, modules mapping */
>> + kasan_populate(kasan_mem_to_shadow((const void *)MODULES_VADDR),
>> + kasan_mem_to_shadow((const void *)BPF_JIT_REGION_END));
>> +
>> for (i = 0; i < PTRS_PER_PTE; i++)
>> set_pte(&kasan_early_shadow_pte[i],
>> mk_pte(virt_to_page(kasan_early_shadow_page),
>> diff --git a/arch/riscv/mm/physaddr.c b/arch/riscv/mm/physaddr.c
>> index e8e4dcd39fed..35703d5ef5fd 100644
>> --- a/arch/riscv/mm/physaddr.c
>> +++ b/arch/riscv/mm/physaddr.c
>> @@ -23,7 +23,7 @@ EXPORT_SYMBOL(__virt_to_phys);
>>
>> phys_addr_t __phys_addr_symbol(unsigned long x)
>> {
>> - unsigned long kernel_start = (unsigned long)PAGE_OFFSET;
>> + unsigned long kernel_start = (unsigned long)kernel_virt_addr;
>> unsigned long kernel_end = (unsigned long)_end;
>>
>> /*
>
> This is breaking boot for me with CONFIG_STRICT_KERNEL_RWX=n. I'm not
> even really convinced that's a useful config to support, but it's
> currently optional and I'd prefer to avoid breaking it if possible.
>
> I can't quite figure out what's going on here and I'm pretty much tired
> out for tonight. LMK if you don't have time to look at it and I'll try
> to give it another shot.
I'm taking a look at that.
Thanks,
Alex
Powered by blists - more mailing lists