forked from mirrors/linux
		
	Introduce CONFIG_STACKLEAK_RUNTIME_DISABLE option, which provides 'stack_erasing' sysctl. It can be used in runtime to control kernel stack erasing for kernels built with CONFIG_GCC_PLUGIN_STACKLEAK. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Alexander Popov <alex.popov@linux.com> Tested-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
		
			
				
	
	
		
			35 lines
		
	
	
	
		
			909 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			35 lines
		
	
	
	
		
			909 B
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_STACKLEAK_H
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#define _LINUX_STACKLEAK_H
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#include <linux/sched.h>
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#include <linux/sched/task_stack.h>
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/*
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 * Check that the poison value points to the unused hole in the
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 * virtual memory map for your platform.
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 */
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#define STACKLEAK_POISON -0xBEEF
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#define STACKLEAK_SEARCH_DEPTH 128
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#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
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#include <asm/stacktrace.h>
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static inline void stackleak_task_init(struct task_struct *t)
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{
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	t->lowest_stack = (unsigned long)end_of_stack(t) + sizeof(unsigned long);
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# ifdef CONFIG_STACKLEAK_METRICS
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	t->prev_lowest_stack = t->lowest_stack;
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# endif
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}
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#ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
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int stack_erasing_sysctl(struct ctl_table *table, int write,
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			void __user *buffer, size_t *lenp, loff_t *ppos);
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#endif
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#else /* !CONFIG_GCC_PLUGIN_STACKLEAK */
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static inline void stackleak_task_init(struct task_struct *t) { }
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#endif
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#endif
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