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/* SPDX-License-Identifier: GPL-2.0 */#ifndef __TRACE_PROBE_KERNEL_H_#define __TRACE_PROBE_KERNEL_H_ #define FAULT_STRING "(fault)" /* * This depends on trace_probe.h, but can not include it due to * the way trace_probe_tmpl.h is used by trace_kprobe.c and trace_eprobe.c. * Which means that any other user must include trace_probe.h before including * this file. *//* Return the length of string -- including null terminal byte */static nokprobe_inline intkern_fetch_store_strlen_user(unsigned long addr){	const void __user *uaddr =  (__force const void __user *)addr;	int ret; 	ret = strnlen_user_nofault(uaddr, MAX_STRING_SIZE);	/*	 * strnlen_user_nofault returns zero on fault, insert the	 * FAULT_STRING when that occurs.	 */	if (ret <= 0)		return strlen(FAULT_STRING) + 1;	return ret;} /* Return the length of string -- including null terminal byte */static nokprobe_inline intkern_fetch_store_strlen(unsigned long addr){	int ret, len = 0;	u8 c; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE	if (addr < TASK_SIZE)		return kern_fetch_store_strlen_user(addr);#endif 	do {		ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1);		len++;	} while (c && ret == 0 && len < MAX_STRING_SIZE); 	/* For faults, return enough to hold the FAULT_STRING */	return (ret < 0) ? strlen(FAULT_STRING) + 1 : len;} static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void *base, int len){	if (ret >= 0) {		*(u32 *)dest = make_data_loc(ret, __dest - base);	} else {		strscpy(__dest, FAULT_STRING, len);		ret = strlen(__dest) + 1;	}} /* * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf * with max length and relative data location. */static nokprobe_inline intkern_fetch_store_string_user(unsigned long addr, void *dest, void *base){	const void __user *uaddr =  (__force const void __user *)addr;	int maxlen = get_loc_len(*(u32 *)dest);	void *__dest;	long ret; 	if (unlikely(!maxlen))		return -ENOMEM; 	__dest = get_loc_data(dest, base); 	ret = strncpy_from_user_nofault(__dest, uaddr, maxlen);	set_data_loc(ret, dest, __dest, base, maxlen); 	return ret;} /* * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max * length and relative data location. */static nokprobe_inline intkern_fetch_store_string(unsigned long addr, void *dest, void *base){	int maxlen = get_loc_len(*(u32 *)dest);	void *__dest;	long ret; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE	if ((unsigned long)addr < TASK_SIZE)		return kern_fetch_store_string_user(addr, dest, base);#endif 	if (unlikely(!maxlen))		return -ENOMEM; 	__dest = get_loc_data(dest, base); 	/*	 * Try to get string again, since the string can be changed while	 * probing.	 */	ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen);	set_data_loc(ret, dest, __dest, base, maxlen); 	return ret;} #endif /* __TRACE_PROBE_KERNEL_H_ */