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50f176175e
Parsing and ignoring 'nokaslr' can be done from anywhere, except from the code that runs very early and is therefore built with limitations on the kind of relocations it is permitted to use. So move it to a source file that is part of the ordinary kernel build. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20231129111555.3594833-63-ardb@google.com Signed-off-by: Will Deacon <will@kernel.org>
45 lines
1.1 KiB
C
45 lines
1.1 KiB
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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static int __init parse_nokaslr(char *unused)
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{
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/* nokaslr param handling is done by early cpufeature code */
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return 0;
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}
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early_param("nokaslr", parse_nokaslr);
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