forked from mirrors/linux
		
	With KCSAN enabled, end_of_stack() can get out-of-lined. Force it inline. Fixes the following warnings: vmlinux.o: warning: objtool: check_stackleak_irqoff+0x2b: call to end_of_stack() leaves .noinstr.text section Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/cc1b4d73d3a428a00d206242a68fdf99a934ca7b.1681320026.git.jpoimboe@kernel.org
		
			
				
	
	
		
			128 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			128 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_SCHED_TASK_STACK_H
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#define _LINUX_SCHED_TASK_STACK_H
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/*
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 * task->stack (kernel stack) handling interfaces:
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 */
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#include <linux/sched.h>
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#include <linux/magic.h>
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#ifdef CONFIG_THREAD_INFO_IN_TASK
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/*
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 * When accessing the stack of a non-current task that might exit, use
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 * try_get_task_stack() instead.  task_stack_page will return a pointer
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 * that could get freed out from under you.
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 */
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static __always_inline void *task_stack_page(const struct task_struct *task)
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{
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	return task->stack;
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}
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#define setup_thread_stack(new,old)	do { } while(0)
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static __always_inline unsigned long *end_of_stack(const struct task_struct *task)
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{
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#ifdef CONFIG_STACK_GROWSUP
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	return (unsigned long *)((unsigned long)task->stack + THREAD_SIZE) - 1;
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#else
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	return task->stack;
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#endif
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}
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#elif !defined(__HAVE_THREAD_FUNCTIONS)
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#define task_stack_page(task)	((void *)(task)->stack)
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static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
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{
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	*task_thread_info(p) = *task_thread_info(org);
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	task_thread_info(p)->task = p;
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}
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/*
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 * Return the address of the last usable long on the stack.
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 *
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 * When the stack grows down, this is just above the thread
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 * info struct. Going any lower will corrupt the threadinfo.
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 *
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 * When the stack grows up, this is the highest address.
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 * Beyond that position, we corrupt data on the next page.
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 */
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static inline unsigned long *end_of_stack(struct task_struct *p)
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{
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#ifdef CONFIG_STACK_GROWSUP
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	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
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#else
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	return (unsigned long *)(task_thread_info(p) + 1);
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#endif
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}
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#endif
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#ifdef CONFIG_THREAD_INFO_IN_TASK
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static inline void *try_get_task_stack(struct task_struct *tsk)
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{
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	return refcount_inc_not_zero(&tsk->stack_refcount) ?
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		task_stack_page(tsk) : NULL;
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}
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extern void put_task_stack(struct task_struct *tsk);
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#else
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static inline void *try_get_task_stack(struct task_struct *tsk)
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{
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	return task_stack_page(tsk);
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}
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static inline void put_task_stack(struct task_struct *tsk) {}
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#endif
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void exit_task_stack_account(struct task_struct *tsk);
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#define task_stack_end_corrupted(task) \
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		(*(end_of_stack(task)) != STACK_END_MAGIC)
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static inline int object_is_on_stack(const void *obj)
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{
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	void *stack = task_stack_page(current);
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	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
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}
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extern void thread_stack_cache_init(void);
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#ifdef CONFIG_DEBUG_STACK_USAGE
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static inline unsigned long stack_not_used(struct task_struct *p)
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{
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	unsigned long *n = end_of_stack(p);
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	do { 	/* Skip over canary */
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# ifdef CONFIG_STACK_GROWSUP
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		n--;
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# else
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		n++;
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# endif
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	} while (!*n);
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# ifdef CONFIG_STACK_GROWSUP
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	return (unsigned long)end_of_stack(p) - (unsigned long)n;
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# else
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	return (unsigned long)n - (unsigned long)end_of_stack(p);
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# endif
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}
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#endif
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extern void set_task_stack_end_magic(struct task_struct *tsk);
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#ifndef __HAVE_ARCH_KSTACK_END
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static inline int kstack_end(void *addr)
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{
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	/* Reliable end of stack detection:
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	 * Some APM bios versions misalign the stack
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	 */
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	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
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}
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#endif
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#endif /* _LINUX_SCHED_TASK_STACK_H */
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