37 lines
859 B
C
37 lines
859 B
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_STACKPROTECTOR_H
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#define _LINUX_STACKPROTECTOR_H 1
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#include <linux/compiler.h>
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#include <linux/sched.h>
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#include <linux/random.h>
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/*
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* On 64-bit architectures, protect against non-terminated C string overflows
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* by zeroing out the first byte of the canary; this leaves 56 bits of entropy.
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*/
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#ifdef CONFIG_64BIT
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# ifdef __LITTLE_ENDIAN
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# define CANARY_MASK 0xffffffffffffff00UL
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# else /* big endian, 64 bits: */
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# define CANARY_MASK 0x00ffffffffffffffUL
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# endif
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#else /* 32 bits: */
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# define CANARY_MASK 0xffffffffUL
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#endif
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static inline unsigned long get_random_canary(void)
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{
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return get_random_long() & CANARY_MASK;
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}
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#if defined(CONFIG_STACKPROTECTOR) || defined(CONFIG_ARM64_PTR_AUTH)
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# include <asm/stackprotector.h>
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#else
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static inline void boot_init_stack_canary(void)
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{
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}
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#endif
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#endif
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