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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/xtensa/mm/kasan_init.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/xtensa/mm/kasan_init.c')
-rw-r--r-- | arch/xtensa/mm/kasan_init.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/xtensa/mm/kasan_init.c b/arch/xtensa/mm/kasan_init.c new file mode 100644 index 000000000..1fef24db2 --- /dev/null +++ b/arch/xtensa/mm/kasan_init.c @@ -0,0 +1,104 @@ +/* + * Xtensa KASAN shadow map initialization + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2017 Cadence Design Systems Inc. + */ + +#include <linux/memblock.h> +#include <linux/init_task.h> +#include <linux/kasan.h> +#include <linux/kernel.h> +#include <asm/initialize_mmu.h> +#include <asm/tlbflush.h> +#include <asm/traps.h> + +void __init kasan_early_init(void) +{ + unsigned long vaddr = KASAN_SHADOW_START; + pmd_t *pmd = pmd_off_k(vaddr); + int i; + + for (i = 0; i < PTRS_PER_PTE; ++i) + set_pte(kasan_early_shadow_pte + i, + mk_pte(virt_to_page(kasan_early_shadow_page), + PAGE_KERNEL)); + + for (vaddr = 0; vaddr < KASAN_SHADOW_SIZE; vaddr += PMD_SIZE, ++pmd) { + BUG_ON(!pmd_none(*pmd)); + set_pmd(pmd, __pmd((unsigned long)kasan_early_shadow_pte)); + } + early_trap_init(); +} + +static void __init populate(void *start, void *end) +{ + unsigned long n_pages = (end - start) / PAGE_SIZE; + unsigned long n_pmds = n_pages / PTRS_PER_PTE; + unsigned long i, j; + unsigned long vaddr = (unsigned long)start; + pmd_t *pmd = pmd_off_k(vaddr); + pte_t *pte = memblock_alloc(n_pages * sizeof(pte_t), PAGE_SIZE); + + if (!pte) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", + __func__, n_pages * sizeof(pte_t), PAGE_SIZE); + + pr_debug("%s: %p - %p\n", __func__, start, end); + + for (i = j = 0; i < n_pmds; ++i) { + int k; + + for (k = 0; k < PTRS_PER_PTE; ++k, ++j) { + phys_addr_t phys = + memblock_phys_alloc_range(PAGE_SIZE, PAGE_SIZE, + 0, + MEMBLOCK_ALLOC_ANYWHERE); + + if (!phys) + panic("Failed to allocate page table page\n"); + + set_pte(pte + j, pfn_pte(PHYS_PFN(phys), PAGE_KERNEL)); + } + } + + for (i = 0; i < n_pmds ; ++i, pte += PTRS_PER_PTE) + set_pmd(pmd + i, __pmd((unsigned long)pte)); + + local_flush_tlb_all(); + memset(start, 0, end - start); +} + +void __init kasan_init(void) +{ + int i; + + BUILD_BUG_ON(KASAN_SHADOW_OFFSET != KASAN_SHADOW_START - + (KASAN_START_VADDR >> KASAN_SHADOW_SCALE_SHIFT)); + BUILD_BUG_ON(VMALLOC_START < KASAN_START_VADDR); + + /* + * Replace shadow map pages that cover addresses from VMALLOC area + * start to the end of KSEG with clean writable pages. + */ + populate(kasan_mem_to_shadow((void *)VMALLOC_START), + kasan_mem_to_shadow((void *)XCHAL_KSEG_BYPASS_VADDR)); + + /* + * Write protect kasan_early_shadow_page and zero-initialize it again. + */ + for (i = 0; i < PTRS_PER_PTE; ++i) + set_pte(kasan_early_shadow_pte + i, + mk_pte(virt_to_page(kasan_early_shadow_page), + PAGE_KERNEL_RO)); + + local_flush_tlb_all(); + memset(kasan_early_shadow_page, 0, PAGE_SIZE); + + /* At this point kasan is fully initialized. Enable error messages. */ + current->kasan_depth = 0; + pr_info("KernelAddressSanitizer initialized\n"); +} |