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| 2 | |
| 3 | * Copyright (C) 2016 Linaro Ltd <[email protected]>
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| 4 |
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| 5 |
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| 6 | #include <linux/cache.h>
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| 7 | #include <linux/init.h>
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| 8 | #include <linux/printk.h>
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| 9 |
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| 10 | #include <asm/cpufeature.h>
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| 11 | #include <asm/memory.h>
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| 12 |
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| 13 | bool __ro_after_init __kaslr_is_enabled = false;
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| 14 |
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| 15 | void __init kaslr_init(void)
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| 16 | {
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| 17 | if (kaslr_disabled_cmdline()) {
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| 18 | pr_info("KASLR disabled on command line\n");
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| 19 | return;
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| 20 | }
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| 21 |
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| 22 | |
| 23 | * The KASLR offset modulo MIN_KIMG_ALIGN is taken from the physical
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| 24 | * placement of the image rather than from the seed, so a displacement
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| 25 | * of less than MIN_KIMG_ALIGN means that no seed was provided.
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| 26 |
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| 27 | if (kaslr_offset() < MIN_KIMG_ALIGN) {
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| 28 | pr_warn("KASLR disabled due to lack of seed\n");
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| 29 | return;
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| 30 | }
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| 31 |
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| 32 | pr_info("KASLR enabled\n");
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| 33 | __kaslr_is_enabled = true;
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| 34 | }
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| 35 |
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| 36 | static int __init parse_nokaslr(char *unused)
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| 37 | {
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| 38 |
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| 39 | return 0;
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| 40 | }
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| 41 | early_param("nokaslr", parse_nokaslr);
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