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b3883a9a1f
This has nothing to do with random.c and everything to do with stack protectors. Yes, it uses randomness. But many things use randomness. random.h and random.c are concerned with the generation of randomness, not with each and every use. So move this function into the more specific stackprotector.h file where it belongs. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
36 lines
859 B
C
36 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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