39 lines
957 B
C
39 lines
957 B
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2016 Linaro Ltd <ard.biesheuvel@linaro.org>
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*/
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#include <linux/cache.h>
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#include <linux/init.h>
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#include <linux/printk.h>
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#include <asm/cpufeature.h>
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#include <asm/memory.h>
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u16 __initdata memstart_offset_seed;
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bool __ro_after_init __kaslr_is_enabled = false;
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void __init kaslr_init(void)
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{
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if (cpuid_feature_extract_unsigned_field(arm64_sw_feature_override.val &
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arm64_sw_feature_override.mask,
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ARM64_SW_FEATURE_OVERRIDE_NOKASLR)) {
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pr_info("KASLR disabled on command line\n");
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return;
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}
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/*
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* The KASLR offset modulo MIN_KIMG_ALIGN is taken from the physical
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* placement of the image rather than from the seed, so a displacement
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* of less than MIN_KIMG_ALIGN means that no seed was provided.
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*/
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if (kaslr_offset() < MIN_KIMG_ALIGN) {
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pr_warn("KASLR disabled due to lack of seed\n");
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return;
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}
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pr_info("KASLR enabled\n");
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__kaslr_is_enabled = true;
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}
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