xref: /linux-6.15/include/linux/compat.h (revision da650ada)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_COMPAT_H
3 #define _LINUX_COMPAT_H
4 /*
5  * These are the type definitions for the architecture specific
6  * syscall compatibility layer.
7  */
8 
9 #include <linux/types.h>
10 #include <linux/time.h>
11 
12 #include <linux/stat.h>
13 #include <linux/param.h>	/* for HZ */
14 #include <linux/sem.h>
15 #include <linux/socket.h>
16 #include <linux/if.h>
17 #include <linux/fs.h>
18 #include <linux/aio_abi.h>	/* for aio_context_t */
19 #include <linux/uaccess.h>
20 #include <linux/unistd.h>
21 
22 #include <asm/compat.h>
23 
24 #ifdef CONFIG_COMPAT
25 #include <asm/siginfo.h>
26 #include <asm/signal.h>
27 #endif
28 
29 #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
30 /*
31  * It may be useful for an architecture to override the definitions of the
32  * COMPAT_SYSCALL_DEFINE0 and COMPAT_SYSCALL_DEFINEx() macros, in particular
33  * to use a different calling convention for syscalls. To allow for that,
34  + the prototypes for the compat_sys_*() functions below will *not* be included
35  * if CONFIG_ARCH_HAS_SYSCALL_WRAPPER is enabled.
36  */
37 #include <asm/syscall_wrapper.h>
38 #endif /* CONFIG_ARCH_HAS_SYSCALL_WRAPPER */
39 
40 #ifndef COMPAT_USE_64BIT_TIME
41 #define COMPAT_USE_64BIT_TIME 0
42 #endif
43 
44 #ifndef __SC_DELOUSE
45 #define __SC_DELOUSE(t,v) ((__force t)(unsigned long)(v))
46 #endif
47 
48 #ifndef COMPAT_SYSCALL_DEFINE0
49 #define COMPAT_SYSCALL_DEFINE0(name) \
50 	asmlinkage long compat_sys_##name(void); \
51 	ALLOW_ERROR_INJECTION(compat_sys_##name, ERRNO); \
52 	asmlinkage long compat_sys_##name(void)
53 #endif /* COMPAT_SYSCALL_DEFINE0 */
54 
55 #define COMPAT_SYSCALL_DEFINE1(name, ...) \
56         COMPAT_SYSCALL_DEFINEx(1, _##name, __VA_ARGS__)
57 #define COMPAT_SYSCALL_DEFINE2(name, ...) \
58 	COMPAT_SYSCALL_DEFINEx(2, _##name, __VA_ARGS__)
59 #define COMPAT_SYSCALL_DEFINE3(name, ...) \
60 	COMPAT_SYSCALL_DEFINEx(3, _##name, __VA_ARGS__)
61 #define COMPAT_SYSCALL_DEFINE4(name, ...) \
62 	COMPAT_SYSCALL_DEFINEx(4, _##name, __VA_ARGS__)
63 #define COMPAT_SYSCALL_DEFINE5(name, ...) \
64 	COMPAT_SYSCALL_DEFINEx(5, _##name, __VA_ARGS__)
65 #define COMPAT_SYSCALL_DEFINE6(name, ...) \
66 	COMPAT_SYSCALL_DEFINEx(6, _##name, __VA_ARGS__)
67 
68 /*
69  * The asmlinkage stub is aliased to a function named __se_compat_sys_*() which
70  * sign-extends 32-bit ints to longs whenever needed. The actual work is
71  * done within __do_compat_sys_*().
72  */
73 #ifndef COMPAT_SYSCALL_DEFINEx
74 #define COMPAT_SYSCALL_DEFINEx(x, name, ...)					\
75 	__diag_push();								\
76 	__diag_ignore(GCC, 8, "-Wattribute-alias",				\
77 		      "Type aliasing is used to sanitize syscall arguments");\
78 	asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
79 	asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))	\
80 		__attribute__((alias(__stringify(__se_compat_sys##name))));	\
81 	ALLOW_ERROR_INJECTION(compat_sys##name, ERRNO);				\
82 	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
83 	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));	\
84 	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\
85 	{									\
86 		long ret = __do_compat_sys##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));\
87 		__MAP(x,__SC_TEST,__VA_ARGS__);					\
88 		return ret;							\
89 	}									\
90 	__diag_pop();								\
91 	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
92 #endif /* COMPAT_SYSCALL_DEFINEx */
93 
94 struct compat_iovec {
95 	compat_uptr_t	iov_base;
96 	compat_size_t	iov_len;
97 };
98 
99 #ifdef CONFIG_COMPAT
100 
101 #ifndef compat_user_stack_pointer
102 #define compat_user_stack_pointer() current_user_stack_pointer()
103 #endif
104 #ifndef compat_sigaltstack	/* we'll need that for MIPS */
105 typedef struct compat_sigaltstack {
106 	compat_uptr_t			ss_sp;
107 	int				ss_flags;
108 	compat_size_t			ss_size;
109 } compat_stack_t;
110 #endif
111 #ifndef COMPAT_MINSIGSTKSZ
112 #define COMPAT_MINSIGSTKSZ	MINSIGSTKSZ
113 #endif
114 
115 #define compat_jiffies_to_clock_t(x)	\
116 		(((unsigned long)(x) * COMPAT_USER_HZ) / HZ)
117 
118 typedef __compat_uid32_t	compat_uid_t;
119 typedef __compat_gid32_t	compat_gid_t;
120 
121 struct compat_sel_arg_struct;
122 struct rusage;
123 
124 struct old_itimerval32;
125 
126 struct compat_tms {
127 	compat_clock_t		tms_utime;
128 	compat_clock_t		tms_stime;
129 	compat_clock_t		tms_cutime;
130 	compat_clock_t		tms_cstime;
131 };
132 
133 #define _COMPAT_NSIG_WORDS	(_COMPAT_NSIG / _COMPAT_NSIG_BPW)
134 
135 typedef struct {
136 	compat_sigset_word	sig[_COMPAT_NSIG_WORDS];
137 } compat_sigset_t;
138 
139 int set_compat_user_sigmask(const compat_sigset_t __user *umask,
140 			    size_t sigsetsize);
141 
142 struct compat_sigaction {
143 #ifndef __ARCH_HAS_IRIX_SIGACTION
144 	compat_uptr_t			sa_handler;
145 	compat_ulong_t			sa_flags;
146 #else
147 	compat_uint_t			sa_flags;
148 	compat_uptr_t			sa_handler;
149 #endif
150 #ifdef __ARCH_HAS_SA_RESTORER
151 	compat_uptr_t			sa_restorer;
152 #endif
153 	compat_sigset_t			sa_mask __packed;
154 };
155 
156 typedef union compat_sigval {
157 	compat_int_t	sival_int;
158 	compat_uptr_t	sival_ptr;
159 } compat_sigval_t;
160 
161 typedef struct compat_siginfo {
162 	int si_signo;
163 #ifndef __ARCH_HAS_SWAPPED_SIGINFO
164 	int si_errno;
165 	int si_code;
166 #else
167 	int si_code;
168 	int si_errno;
169 #endif
170 
171 	union {
172 		int _pad[128/sizeof(int) - 3];
173 
174 		/* kill() */
175 		struct {
176 			compat_pid_t _pid;	/* sender's pid */
177 			__compat_uid32_t _uid;	/* sender's uid */
178 		} _kill;
179 
180 		/* POSIX.1b timers */
181 		struct {
182 			compat_timer_t _tid;	/* timer id */
183 			int _overrun;		/* overrun count */
184 			compat_sigval_t _sigval;	/* same as below */
185 		} _timer;
186 
187 		/* POSIX.1b signals */
188 		struct {
189 			compat_pid_t _pid;	/* sender's pid */
190 			__compat_uid32_t _uid;	/* sender's uid */
191 			compat_sigval_t _sigval;
192 		} _rt;
193 
194 		/* SIGCHLD */
195 		struct {
196 			compat_pid_t _pid;	/* which child */
197 			__compat_uid32_t _uid;	/* sender's uid */
198 			int _status;		/* exit code */
199 			compat_clock_t _utime;
200 			compat_clock_t _stime;
201 		} _sigchld;
202 
203 #ifdef CONFIG_X86_X32_ABI
204 		/* SIGCHLD (x32 version) */
205 		struct {
206 			compat_pid_t _pid;	/* which child */
207 			__compat_uid32_t _uid;	/* sender's uid */
208 			int _status;		/* exit code */
209 			compat_s64 _utime;
210 			compat_s64 _stime;
211 		} _sigchld_x32;
212 #endif
213 
214 		/* SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGTRAP, SIGEMT */
215 		struct {
216 			compat_uptr_t _addr;	/* faulting insn/memory ref. */
217 #ifdef __ARCH_SI_TRAPNO
218 			int _trapno;	/* TRAP # which caused the signal */
219 #endif
220 #define __COMPAT_ADDR_BND_PKEY_PAD  (__alignof__(compat_uptr_t) < sizeof(short) ? \
221 				     sizeof(short) : __alignof__(compat_uptr_t))
222 			union {
223 				/*
224 				 * used when si_code=BUS_MCEERR_AR or
225 				 * used when si_code=BUS_MCEERR_AO
226 				 */
227 				short int _addr_lsb;	/* Valid LSB of the reported address. */
228 				/* used when si_code=SEGV_BNDERR */
229 				struct {
230 					char _dummy_bnd[__COMPAT_ADDR_BND_PKEY_PAD];
231 					compat_uptr_t _lower;
232 					compat_uptr_t _upper;
233 				} _addr_bnd;
234 				/* used when si_code=SEGV_PKUERR */
235 				struct {
236 					char _dummy_pkey[__COMPAT_ADDR_BND_PKEY_PAD];
237 					u32 _pkey;
238 				} _addr_pkey;
239 			};
240 		} _sigfault;
241 
242 		/* SIGPOLL */
243 		struct {
244 			compat_long_t _band;	/* POLL_IN, POLL_OUT, POLL_MSG */
245 			int _fd;
246 		} _sigpoll;
247 
248 		struct {
249 			compat_uptr_t _call_addr; /* calling user insn */
250 			int _syscall;	/* triggering system call number */
251 			unsigned int _arch;	/* AUDIT_ARCH_* of syscall */
252 		} _sigsys;
253 	} _sifields;
254 } compat_siginfo_t;
255 
256 struct compat_rlimit {
257 	compat_ulong_t	rlim_cur;
258 	compat_ulong_t	rlim_max;
259 };
260 
261 struct compat_rusage {
262 	struct old_timeval32 ru_utime;
263 	struct old_timeval32 ru_stime;
264 	compat_long_t	ru_maxrss;
265 	compat_long_t	ru_ixrss;
266 	compat_long_t	ru_idrss;
267 	compat_long_t	ru_isrss;
268 	compat_long_t	ru_minflt;
269 	compat_long_t	ru_majflt;
270 	compat_long_t	ru_nswap;
271 	compat_long_t	ru_inblock;
272 	compat_long_t	ru_oublock;
273 	compat_long_t	ru_msgsnd;
274 	compat_long_t	ru_msgrcv;
275 	compat_long_t	ru_nsignals;
276 	compat_long_t	ru_nvcsw;
277 	compat_long_t	ru_nivcsw;
278 };
279 
280 extern int put_compat_rusage(const struct rusage *,
281 			     struct compat_rusage __user *);
282 
283 struct compat_siginfo;
284 struct __compat_aio_sigset;
285 
286 struct compat_dirent {
287 	u32		d_ino;
288 	compat_off_t	d_off;
289 	u16		d_reclen;
290 	char		d_name[256];
291 };
292 
293 struct compat_ustat {
294 	compat_daddr_t		f_tfree;
295 	compat_ino_t		f_tinode;
296 	char			f_fname[6];
297 	char			f_fpack[6];
298 };
299 
300 #define COMPAT_SIGEV_PAD_SIZE	((SIGEV_MAX_SIZE/sizeof(int)) - 3)
301 
302 typedef struct compat_sigevent {
303 	compat_sigval_t sigev_value;
304 	compat_int_t sigev_signo;
305 	compat_int_t sigev_notify;
306 	union {
307 		compat_int_t _pad[COMPAT_SIGEV_PAD_SIZE];
308 		compat_int_t _tid;
309 
310 		struct {
311 			compat_uptr_t _function;
312 			compat_uptr_t _attribute;
313 		} _sigev_thread;
314 	} _sigev_un;
315 } compat_sigevent_t;
316 
317 struct compat_ifmap {
318 	compat_ulong_t mem_start;
319 	compat_ulong_t mem_end;
320 	unsigned short base_addr;
321 	unsigned char irq;
322 	unsigned char dma;
323 	unsigned char port;
324 };
325 
326 struct compat_if_settings {
327 	unsigned int type;	/* Type of physical device or protocol */
328 	unsigned int size;	/* Size of the data allocated by the caller */
329 	compat_uptr_t ifs_ifsu;	/* union of pointers */
330 };
331 
332 struct compat_ifreq {
333 	union {
334 		char	ifrn_name[IFNAMSIZ];    /* if name, e.g. "en0" */
335 	} ifr_ifrn;
336 	union {
337 		struct	sockaddr ifru_addr;
338 		struct	sockaddr ifru_dstaddr;
339 		struct	sockaddr ifru_broadaddr;
340 		struct	sockaddr ifru_netmask;
341 		struct	sockaddr ifru_hwaddr;
342 		short	ifru_flags;
343 		compat_int_t	ifru_ivalue;
344 		compat_int_t	ifru_mtu;
345 		struct	compat_ifmap ifru_map;
346 		char	ifru_slave[IFNAMSIZ];   /* Just fits the size */
347 		char	ifru_newname[IFNAMSIZ];
348 		compat_caddr_t	ifru_data;
349 		struct	compat_if_settings ifru_settings;
350 	} ifr_ifru;
351 };
352 
353 struct compat_ifconf {
354 	compat_int_t	ifc_len;                /* size of buffer */
355 	compat_caddr_t  ifcbuf;
356 };
357 
358 struct compat_robust_list {
359 	compat_uptr_t			next;
360 };
361 
362 struct compat_robust_list_head {
363 	struct compat_robust_list	list;
364 	compat_long_t			futex_offset;
365 	compat_uptr_t			list_op_pending;
366 };
367 
368 #ifdef CONFIG_COMPAT_OLD_SIGACTION
369 struct compat_old_sigaction {
370 	compat_uptr_t			sa_handler;
371 	compat_old_sigset_t		sa_mask;
372 	compat_ulong_t			sa_flags;
373 	compat_uptr_t			sa_restorer;
374 };
375 #endif
376 
377 struct compat_keyctl_kdf_params {
378 	compat_uptr_t hashname;
379 	compat_uptr_t otherinfo;
380 	__u32 otherinfolen;
381 	__u32 __spare[8];
382 };
383 
384 struct compat_statfs;
385 struct compat_statfs64;
386 struct compat_old_linux_dirent;
387 struct compat_linux_dirent;
388 struct linux_dirent64;
389 struct compat_msghdr;
390 struct compat_mmsghdr;
391 struct compat_sysinfo;
392 struct compat_sysctl_args;
393 struct compat_kexec_segment;
394 struct compat_mq_attr;
395 struct compat_msgbuf;
396 
397 #define BITS_PER_COMPAT_LONG    (8*sizeof(compat_long_t))
398 
399 #define BITS_TO_COMPAT_LONGS(bits) DIV_ROUND_UP(bits, BITS_PER_COMPAT_LONG)
400 
401 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
402 		       unsigned long bitmap_size);
403 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
404 		       unsigned long bitmap_size);
405 void copy_siginfo_to_external32(struct compat_siginfo *to,
406 		const struct kernel_siginfo *from);
407 int copy_siginfo_from_user32(kernel_siginfo_t *to,
408 		const struct compat_siginfo __user *from);
409 int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
410 		const kernel_siginfo_t *from);
411 #ifndef copy_siginfo_to_user32
412 #define copy_siginfo_to_user32 __copy_siginfo_to_user32
413 #endif
414 int get_compat_sigevent(struct sigevent *event,
415 		const struct compat_sigevent __user *u_event);
416 
417 extern int get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat);
418 
419 /*
420  * Defined inline such that size can be compile time constant, which avoids
421  * CONFIG_HARDENED_USERCOPY complaining about copies from task_struct
422  */
423 static inline int
424 put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set,
425 		  unsigned int size)
426 {
427 	/* size <= sizeof(compat_sigset_t) <= sizeof(sigset_t) */
428 #ifdef __BIG_ENDIAN
429 	compat_sigset_t v;
430 	switch (_NSIG_WORDS) {
431 	case 4: v.sig[7] = (set->sig[3] >> 32); v.sig[6] = set->sig[3];
432 		fallthrough;
433 	case 3: v.sig[5] = (set->sig[2] >> 32); v.sig[4] = set->sig[2];
434 		fallthrough;
435 	case 2: v.sig[3] = (set->sig[1] >> 32); v.sig[2] = set->sig[1];
436 		fallthrough;
437 	case 1: v.sig[1] = (set->sig[0] >> 32); v.sig[0] = set->sig[0];
438 	}
439 	return copy_to_user(compat, &v, size) ? -EFAULT : 0;
440 #else
441 	return copy_to_user(compat, set, size) ? -EFAULT : 0;
442 #endif
443 }
444 
445 #ifdef CONFIG_CPU_BIG_ENDIAN
446 #define unsafe_put_compat_sigset(compat, set, label) do {		\
447 	compat_sigset_t __user *__c = compat;				\
448 	const sigset_t *__s = set;					\
449 									\
450 	switch (_NSIG_WORDS) {						\
451 	case 4:								\
452 		unsafe_put_user(__s->sig[3] >> 32, &__c->sig[7], label);	\
453 		unsafe_put_user(__s->sig[3], &__c->sig[6], label);	\
454 		fallthrough;						\
455 	case 3:								\
456 		unsafe_put_user(__s->sig[2] >> 32, &__c->sig[5], label);	\
457 		unsafe_put_user(__s->sig[2], &__c->sig[4], label);	\
458 		fallthrough;						\
459 	case 2:								\
460 		unsafe_put_user(__s->sig[1] >> 32, &__c->sig[3], label);	\
461 		unsafe_put_user(__s->sig[1], &__c->sig[2], label);	\
462 		fallthrough;						\
463 	case 1:								\
464 		unsafe_put_user(__s->sig[0] >> 32, &__c->sig[1], label);	\
465 		unsafe_put_user(__s->sig[0], &__c->sig[0], label);	\
466 	}								\
467 } while (0)
468 
469 #define unsafe_get_compat_sigset(set, compat, label) do {		\
470 	const compat_sigset_t __user *__c = compat;			\
471 	compat_sigset_word hi, lo;					\
472 	sigset_t *__s = set;						\
473 									\
474 	switch (_NSIG_WORDS) {						\
475 	case 4:								\
476 		unsafe_get_user(lo, &__c->sig[7], label);		\
477 		unsafe_get_user(hi, &__c->sig[6], label);		\
478 		__s->sig[3] = hi | (((long)lo) << 32);			\
479 		fallthrough;						\
480 	case 3:								\
481 		unsafe_get_user(lo, &__c->sig[5], label);		\
482 		unsafe_get_user(hi, &__c->sig[4], label);		\
483 		__s->sig[2] = hi | (((long)lo) << 32);			\
484 		fallthrough;						\
485 	case 2:								\
486 		unsafe_get_user(lo, &__c->sig[3], label);		\
487 		unsafe_get_user(hi, &__c->sig[2], label);		\
488 		__s->sig[1] = hi | (((long)lo) << 32);			\
489 		fallthrough;						\
490 	case 1:								\
491 		unsafe_get_user(lo, &__c->sig[1], label);		\
492 		unsafe_get_user(hi, &__c->sig[0], label);		\
493 		__s->sig[0] = hi | (((long)lo) << 32);			\
494 	}								\
495 } while (0)
496 #else
497 #define unsafe_put_compat_sigset(compat, set, label) do {		\
498 	compat_sigset_t __user *__c = compat;				\
499 	const sigset_t *__s = set;					\
500 									\
501 	unsafe_copy_to_user(__c, __s, sizeof(*__c), label);		\
502 } while (0)
503 
504 #define unsafe_get_compat_sigset(set, compat, label) do {		\
505 	const compat_sigset_t __user *__c = compat;			\
506 	sigset_t *__s = set;						\
507 									\
508 	unsafe_copy_from_user(__s, __c, sizeof(*__c), label);		\
509 } while (0)
510 #endif
511 
512 extern int compat_ptrace_request(struct task_struct *child,
513 				 compat_long_t request,
514 				 compat_ulong_t addr, compat_ulong_t data);
515 
516 extern long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
517 			       compat_ulong_t addr, compat_ulong_t data);
518 
519 struct epoll_event;	/* fortunately, this one is fixed-layout */
520 
521 extern void __user *compat_alloc_user_space(unsigned long len);
522 
523 int compat_restore_altstack(const compat_stack_t __user *uss);
524 int __compat_save_altstack(compat_stack_t __user *, unsigned long);
525 #define unsafe_compat_save_altstack(uss, sp, label) do { \
526 	compat_stack_t __user *__uss = uss; \
527 	struct task_struct *t = current; \
528 	unsafe_put_user(ptr_to_compat((void __user *)t->sas_ss_sp), \
529 			&__uss->ss_sp, label); \
530 	unsafe_put_user(t->sas_ss_flags, &__uss->ss_flags, label); \
531 	unsafe_put_user(t->sas_ss_size, &__uss->ss_size, label); \
532 	if (t->sas_ss_flags & SS_AUTODISARM) \
533 		sas_ss_reset(t); \
534 } while (0);
535 
536 /*
537  * These syscall function prototypes are kept in the same order as
538  * include/uapi/asm-generic/unistd.h. Deprecated or obsolete system calls
539  * go below.
540  *
541  * Please note that these prototypes here are only provided for information
542  * purposes, for static analysis, and for linking from the syscall table.
543  * These functions should not be called elsewhere from kernel code.
544  *
545  * As the syscall calling convention may be different from the default
546  * for architectures overriding the syscall calling convention, do not
547  * include the prototypes if CONFIG_ARCH_HAS_SYSCALL_WRAPPER is enabled.
548  */
549 #ifndef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
550 asmlinkage long compat_sys_io_setup(unsigned nr_reqs, u32 __user *ctx32p);
551 asmlinkage long compat_sys_io_submit(compat_aio_context_t ctx_id, int nr,
552 				     u32 __user *iocb);
553 asmlinkage long compat_sys_io_pgetevents(compat_aio_context_t ctx_id,
554 					compat_long_t min_nr,
555 					compat_long_t nr,
556 					struct io_event __user *events,
557 					struct old_timespec32 __user *timeout,
558 					const struct __compat_aio_sigset __user *usig);
559 asmlinkage long compat_sys_io_pgetevents_time64(compat_aio_context_t ctx_id,
560 					compat_long_t min_nr,
561 					compat_long_t nr,
562 					struct io_event __user *events,
563 					struct __kernel_timespec __user *timeout,
564 					const struct __compat_aio_sigset __user *usig);
565 
566 /* fs/cookies.c */
567 asmlinkage long compat_sys_lookup_dcookie(u32, u32, char __user *, compat_size_t);
568 
569 /* fs/eventpoll.c */
570 asmlinkage long compat_sys_epoll_pwait(int epfd,
571 			struct epoll_event __user *events,
572 			int maxevents, int timeout,
573 			const compat_sigset_t __user *sigmask,
574 			compat_size_t sigsetsize);
575 asmlinkage long compat_sys_epoll_pwait2(int epfd,
576 			struct epoll_event __user *events,
577 			int maxevents,
578 			const struct __kernel_timespec __user *timeout,
579 			const compat_sigset_t __user *sigmask,
580 			compat_size_t sigsetsize);
581 
582 /* fs/fcntl.c */
583 asmlinkage long compat_sys_fcntl(unsigned int fd, unsigned int cmd,
584 				 compat_ulong_t arg);
585 asmlinkage long compat_sys_fcntl64(unsigned int fd, unsigned int cmd,
586 				   compat_ulong_t arg);
587 
588 /* fs/ioctl.c */
589 asmlinkage long compat_sys_ioctl(unsigned int fd, unsigned int cmd,
590 				 compat_ulong_t arg);
591 
592 /* fs/open.c */
593 asmlinkage long compat_sys_statfs(const char __user *pathname,
594 				  struct compat_statfs __user *buf);
595 asmlinkage long compat_sys_statfs64(const char __user *pathname,
596 				    compat_size_t sz,
597 				    struct compat_statfs64 __user *buf);
598 asmlinkage long compat_sys_fstatfs(unsigned int fd,
599 				   struct compat_statfs __user *buf);
600 asmlinkage long compat_sys_fstatfs64(unsigned int fd, compat_size_t sz,
601 				     struct compat_statfs64 __user *buf);
602 asmlinkage long compat_sys_truncate(const char __user *, compat_off_t);
603 asmlinkage long compat_sys_ftruncate(unsigned int, compat_ulong_t);
604 /* No generic prototype for truncate64, ftruncate64, fallocate */
605 asmlinkage long compat_sys_openat(int dfd, const char __user *filename,
606 				  int flags, umode_t mode);
607 
608 /* fs/readdir.c */
609 asmlinkage long compat_sys_getdents(unsigned int fd,
610 				    struct compat_linux_dirent __user *dirent,
611 				    unsigned int count);
612 
613 /* fs/read_write.c */
614 asmlinkage long compat_sys_lseek(unsigned int, compat_off_t, unsigned int);
615 /* No generic prototype for pread64 and pwrite64 */
616 asmlinkage ssize_t compat_sys_preadv(compat_ulong_t fd,
617 		const struct iovec __user *vec,
618 		compat_ulong_t vlen, u32 pos_low, u32 pos_high);
619 asmlinkage ssize_t compat_sys_pwritev(compat_ulong_t fd,
620 		const struct iovec __user *vec,
621 		compat_ulong_t vlen, u32 pos_low, u32 pos_high);
622 #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
623 asmlinkage long compat_sys_preadv64(unsigned long fd,
624 		const struct iovec __user *vec,
625 		unsigned long vlen, loff_t pos);
626 #endif
627 
628 #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64
629 asmlinkage long compat_sys_pwritev64(unsigned long fd,
630 		const struct iovec __user *vec,
631 		unsigned long vlen, loff_t pos);
632 #endif
633 
634 /* fs/sendfile.c */
635 asmlinkage long compat_sys_sendfile(int out_fd, int in_fd,
636 				    compat_off_t __user *offset, compat_size_t count);
637 asmlinkage long compat_sys_sendfile64(int out_fd, int in_fd,
638 				    compat_loff_t __user *offset, compat_size_t count);
639 
640 /* fs/select.c */
641 asmlinkage long compat_sys_pselect6_time32(int n, compat_ulong_t __user *inp,
642 				    compat_ulong_t __user *outp,
643 				    compat_ulong_t __user *exp,
644 				    struct old_timespec32 __user *tsp,
645 				    void __user *sig);
646 asmlinkage long compat_sys_pselect6_time64(int n, compat_ulong_t __user *inp,
647 				    compat_ulong_t __user *outp,
648 				    compat_ulong_t __user *exp,
649 				    struct __kernel_timespec __user *tsp,
650 				    void __user *sig);
651 asmlinkage long compat_sys_ppoll_time32(struct pollfd __user *ufds,
652 				 unsigned int nfds,
653 				 struct old_timespec32 __user *tsp,
654 				 const compat_sigset_t __user *sigmask,
655 				 compat_size_t sigsetsize);
656 asmlinkage long compat_sys_ppoll_time64(struct pollfd __user *ufds,
657 				 unsigned int nfds,
658 				 struct __kernel_timespec __user *tsp,
659 				 const compat_sigset_t __user *sigmask,
660 				 compat_size_t sigsetsize);
661 
662 /* fs/signalfd.c */
663 asmlinkage long compat_sys_signalfd4(int ufd,
664 				     const compat_sigset_t __user *sigmask,
665 				     compat_size_t sigsetsize, int flags);
666 
667 /* fs/stat.c */
668 asmlinkage long compat_sys_newfstatat(unsigned int dfd,
669 				      const char __user *filename,
670 				      struct compat_stat __user *statbuf,
671 				      int flag);
672 asmlinkage long compat_sys_newfstat(unsigned int fd,
673 				    struct compat_stat __user *statbuf);
674 
675 /* fs/sync.c: No generic prototype for sync_file_range and sync_file_range2 */
676 
677 /* kernel/exit.c */
678 asmlinkage long compat_sys_waitid(int, compat_pid_t,
679 		struct compat_siginfo __user *, int,
680 		struct compat_rusage __user *);
681 
682 
683 
684 /* kernel/futex.c */
685 asmlinkage long
686 compat_sys_set_robust_list(struct compat_robust_list_head __user *head,
687 			   compat_size_t len);
688 asmlinkage long
689 compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr,
690 			   compat_size_t __user *len_ptr);
691 
692 /* kernel/itimer.c */
693 asmlinkage long compat_sys_getitimer(int which,
694 				     struct old_itimerval32 __user *it);
695 asmlinkage long compat_sys_setitimer(int which,
696 				     struct old_itimerval32 __user *in,
697 				     struct old_itimerval32 __user *out);
698 
699 /* kernel/kexec.c */
700 asmlinkage long compat_sys_kexec_load(compat_ulong_t entry,
701 				      compat_ulong_t nr_segments,
702 				      struct compat_kexec_segment __user *,
703 				      compat_ulong_t flags);
704 
705 /* kernel/posix-timers.c */
706 asmlinkage long compat_sys_timer_create(clockid_t which_clock,
707 			struct compat_sigevent __user *timer_event_spec,
708 			timer_t __user *created_timer_id);
709 
710 /* kernel/ptrace.c */
711 asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
712 				  compat_long_t addr, compat_long_t data);
713 
714 /* kernel/sched/core.c */
715 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
716 				     unsigned int len,
717 				     compat_ulong_t __user *user_mask_ptr);
718 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid,
719 				     unsigned int len,
720 				     compat_ulong_t __user *user_mask_ptr);
721 
722 /* kernel/signal.c */
723 asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
724 				       compat_stack_t __user *uoss_ptr);
725 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset,
726 					 compat_size_t sigsetsize);
727 #ifndef CONFIG_ODD_RT_SIGACTION
728 asmlinkage long compat_sys_rt_sigaction(int,
729 				 const struct compat_sigaction __user *,
730 				 struct compat_sigaction __user *,
731 				 compat_size_t);
732 #endif
733 asmlinkage long compat_sys_rt_sigprocmask(int how, compat_sigset_t __user *set,
734 					  compat_sigset_t __user *oset,
735 					  compat_size_t sigsetsize);
736 asmlinkage long compat_sys_rt_sigpending(compat_sigset_t __user *uset,
737 					 compat_size_t sigsetsize);
738 asmlinkage long compat_sys_rt_sigtimedwait_time32(compat_sigset_t __user *uthese,
739 		struct compat_siginfo __user *uinfo,
740 		struct old_timespec32 __user *uts, compat_size_t sigsetsize);
741 asmlinkage long compat_sys_rt_sigtimedwait_time64(compat_sigset_t __user *uthese,
742 		struct compat_siginfo __user *uinfo,
743 		struct __kernel_timespec __user *uts, compat_size_t sigsetsize);
744 asmlinkage long compat_sys_rt_sigqueueinfo(compat_pid_t pid, int sig,
745 				struct compat_siginfo __user *uinfo);
746 /* No generic prototype for rt_sigreturn */
747 
748 /* kernel/sys.c */
749 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf);
750 asmlinkage long compat_sys_getrlimit(unsigned int resource,
751 				     struct compat_rlimit __user *rlim);
752 asmlinkage long compat_sys_setrlimit(unsigned int resource,
753 				     struct compat_rlimit __user *rlim);
754 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru);
755 
756 /* kernel/time.c */
757 asmlinkage long compat_sys_gettimeofday(struct old_timeval32 __user *tv,
758 		struct timezone __user *tz);
759 asmlinkage long compat_sys_settimeofday(struct old_timeval32 __user *tv,
760 		struct timezone __user *tz);
761 
762 /* kernel/timer.c */
763 asmlinkage long compat_sys_sysinfo(struct compat_sysinfo __user *info);
764 
765 /* ipc/mqueue.c */
766 asmlinkage long compat_sys_mq_open(const char __user *u_name,
767 			int oflag, compat_mode_t mode,
768 			struct compat_mq_attr __user *u_attr);
769 asmlinkage long compat_sys_mq_notify(mqd_t mqdes,
770 			const struct compat_sigevent __user *u_notification);
771 asmlinkage long compat_sys_mq_getsetattr(mqd_t mqdes,
772 			const struct compat_mq_attr __user *u_mqstat,
773 			struct compat_mq_attr __user *u_omqstat);
774 
775 /* ipc/msg.c */
776 asmlinkage long compat_sys_msgctl(int first, int second, void __user *uptr);
777 asmlinkage long compat_sys_msgrcv(int msqid, compat_uptr_t msgp,
778 		compat_ssize_t msgsz, compat_long_t msgtyp, int msgflg);
779 asmlinkage long compat_sys_msgsnd(int msqid, compat_uptr_t msgp,
780 		compat_ssize_t msgsz, int msgflg);
781 
782 /* ipc/sem.c */
783 asmlinkage long compat_sys_semctl(int semid, int semnum, int cmd, int arg);
784 
785 /* ipc/shm.c */
786 asmlinkage long compat_sys_shmctl(int first, int second, void __user *uptr);
787 asmlinkage long compat_sys_shmat(int shmid, compat_uptr_t shmaddr, int shmflg);
788 
789 /* net/socket.c */
790 asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, compat_size_t len,
791 			    unsigned flags, struct sockaddr __user *addr,
792 			    int __user *addrlen);
793 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg,
794 				   unsigned flags);
795 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg,
796 				   unsigned int flags);
797 
798 /* mm/filemap.c: No generic prototype for readahead */
799 
800 /* security/keys/keyctl.c */
801 asmlinkage long compat_sys_keyctl(u32 option,
802 			      u32 arg2, u32 arg3, u32 arg4, u32 arg5);
803 
804 /* arch/example/kernel/sys_example.c */
805 asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr_t __user *argv,
806 		     const compat_uptr_t __user *envp);
807 
808 /* mm/fadvise.c: No generic prototype for fadvise64_64 */
809 
810 /* mm/, CONFIG_MMU only */
811 asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
812 				 compat_ulong_t mode,
813 				 compat_ulong_t __user *nmask,
814 				 compat_ulong_t maxnode, compat_ulong_t flags);
815 asmlinkage long compat_sys_get_mempolicy(int __user *policy,
816 					 compat_ulong_t __user *nmask,
817 					 compat_ulong_t maxnode,
818 					 compat_ulong_t addr,
819 					 compat_ulong_t flags);
820 asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
821 					 compat_ulong_t maxnode);
822 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
823 		compat_ulong_t maxnode, const compat_ulong_t __user *old_nodes,
824 		const compat_ulong_t __user *new_nodes);
825 asmlinkage long compat_sys_move_pages(pid_t pid, compat_ulong_t nr_pages,
826 				      __u32 __user *pages,
827 				      const int __user *nodes,
828 				      int __user *status,
829 				      int flags);
830 
831 asmlinkage long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid,
832 					compat_pid_t pid, int sig,
833 					struct compat_siginfo __user *uinfo);
834 asmlinkage long compat_sys_recvmmsg_time64(int fd, struct compat_mmsghdr __user *mmsg,
835 				    unsigned vlen, unsigned int flags,
836 				    struct __kernel_timespec __user *timeout);
837 asmlinkage long compat_sys_recvmmsg_time32(int fd, struct compat_mmsghdr __user *mmsg,
838 				    unsigned vlen, unsigned int flags,
839 				    struct old_timespec32 __user *timeout);
840 asmlinkage long compat_sys_wait4(compat_pid_t pid,
841 				 compat_uint_t __user *stat_addr, int options,
842 				 struct compat_rusage __user *ru);
843 asmlinkage long compat_sys_fanotify_mark(int, unsigned int, __u32, __u32,
844 					    int, const char __user *);
845 asmlinkage long compat_sys_open_by_handle_at(int mountdirfd,
846 					     struct file_handle __user *handle,
847 					     int flags);
848 asmlinkage long compat_sys_sendmmsg(int fd, struct compat_mmsghdr __user *mmsg,
849 				    unsigned vlen, unsigned int flags);
850 asmlinkage long compat_sys_execveat(int dfd, const char __user *filename,
851 		     const compat_uptr_t __user *argv,
852 		     const compat_uptr_t __user *envp, int flags);
853 asmlinkage ssize_t compat_sys_preadv2(compat_ulong_t fd,
854 		const struct iovec __user *vec,
855 		compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);
856 asmlinkage ssize_t compat_sys_pwritev2(compat_ulong_t fd,
857 		const struct iovec __user *vec,
858 		compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);
859 #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2
860 asmlinkage long  compat_sys_preadv64v2(unsigned long fd,
861 		const struct iovec __user *vec,
862 		unsigned long vlen, loff_t pos, rwf_t flags);
863 #endif
864 
865 #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2
866 asmlinkage long compat_sys_pwritev64v2(unsigned long fd,
867 		const struct iovec __user *vec,
868 		unsigned long vlen, loff_t pos, rwf_t flags);
869 #endif
870 
871 
872 /*
873  * Deprecated system calls which are still defined in
874  * include/uapi/asm-generic/unistd.h and wanted by >= 1 arch
875  */
876 
877 /* __ARCH_WANT_SYSCALL_NO_AT */
878 asmlinkage long compat_sys_open(const char __user *filename, int flags,
879 				umode_t mode);
880 
881 /* __ARCH_WANT_SYSCALL_NO_FLAGS */
882 asmlinkage long compat_sys_signalfd(int ufd,
883 				    const compat_sigset_t __user *sigmask,
884 				    compat_size_t sigsetsize);
885 
886 /* __ARCH_WANT_SYSCALL_OFF_T */
887 asmlinkage long compat_sys_newstat(const char __user *filename,
888 				   struct compat_stat __user *statbuf);
889 asmlinkage long compat_sys_newlstat(const char __user *filename,
890 				    struct compat_stat __user *statbuf);
891 
892 /* __ARCH_WANT_SYSCALL_DEPRECATED */
893 asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
894 		compat_ulong_t __user *outp, compat_ulong_t __user *exp,
895 		struct old_timeval32 __user *tvp);
896 asmlinkage long compat_sys_ustat(unsigned dev, struct compat_ustat __user *u32);
897 asmlinkage long compat_sys_recv(int fd, void __user *buf, compat_size_t len,
898 				unsigned flags);
899 
900 /* obsolete: fs/readdir.c */
901 asmlinkage long compat_sys_old_readdir(unsigned int fd,
902 				       struct compat_old_linux_dirent __user *,
903 				       unsigned int count);
904 
905 /* obsolete: fs/select.c */
906 asmlinkage long compat_sys_old_select(struct compat_sel_arg_struct __user *arg);
907 
908 /* obsolete: ipc */
909 asmlinkage long compat_sys_ipc(u32, int, int, u32, compat_uptr_t, u32);
910 
911 /* obsolete: kernel/signal.c */
912 #ifdef __ARCH_WANT_SYS_SIGPENDING
913 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set);
914 #endif
915 
916 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
917 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *nset,
918 				       compat_old_sigset_t __user *oset);
919 #endif
920 #ifdef CONFIG_COMPAT_OLD_SIGACTION
921 asmlinkage long compat_sys_sigaction(int sig,
922                                    const struct compat_old_sigaction __user *act,
923                                    struct compat_old_sigaction __user *oact);
924 #endif
925 
926 /* obsolete: net/socket.c */
927 asmlinkage long compat_sys_socketcall(int call, u32 __user *args);
928 
929 #endif /* CONFIG_ARCH_HAS_SYSCALL_WRAPPER */
930 
931 
932 /*
933  * For most but not all architectures, "am I in a compat syscall?" and
934  * "am I a compat task?" are the same question.  For architectures on which
935  * they aren't the same question, arch code can override in_compat_syscall.
936  */
937 
938 #ifndef in_compat_syscall
939 static inline bool in_compat_syscall(void) { return is_compat_task(); }
940 #endif
941 
942 /**
943  * ns_to_old_timeval32 - Compat version of ns_to_timeval
944  * @nsec:	the nanoseconds value to be converted
945  *
946  * Returns the old_timeval32 representation of the nsec parameter.
947  */
948 static inline struct old_timeval32 ns_to_old_timeval32(s64 nsec)
949 {
950 	struct __kernel_old_timeval tv;
951 	struct old_timeval32 ctv;
952 
953 	tv = ns_to_kernel_old_timeval(nsec);
954 	ctv.tv_sec = tv.tv_sec;
955 	ctv.tv_usec = tv.tv_usec;
956 
957 	return ctv;
958 }
959 
960 /*
961  * Kernel code should not call compat syscalls (i.e., compat_sys_xyzyyz())
962  * directly.  Instead, use one of the functions which work equivalently, such
963  * as the kcompat_sys_xyzyyz() functions prototyped below.
964  */
965 
966 int kcompat_sys_statfs64(const char __user * pathname, compat_size_t sz,
967 		     struct compat_statfs64 __user * buf);
968 int kcompat_sys_fstatfs64(unsigned int fd, compat_size_t sz,
969 			  struct compat_statfs64 __user * buf);
970 
971 #else /* !CONFIG_COMPAT */
972 
973 #define is_compat_task() (0)
974 /* Ensure no one redefines in_compat_syscall() under !CONFIG_COMPAT */
975 #define in_compat_syscall in_compat_syscall
976 static inline bool in_compat_syscall(void) { return false; }
977 
978 #endif /* CONFIG_COMPAT */
979 
980 /*
981  * Some legacy ABIs like the i386 one use less than natural alignment for 64-bit
982  * types, and will need special compat treatment for that.  Most architectures
983  * don't need that special handling even for compat syscalls.
984  */
985 #ifndef compat_need_64bit_alignment_fixup
986 #define compat_need_64bit_alignment_fixup()		false
987 #endif
988 
989 /*
990  * A pointer passed in from user mode. This should not
991  * be used for syscall parameters, just declare them
992  * as pointers because the syscall entry code will have
993  * appropriately converted them already.
994  */
995 #ifndef compat_ptr
996 static inline void __user *compat_ptr(compat_uptr_t uptr)
997 {
998 	return (void __user *)(unsigned long)uptr;
999 }
1000 #endif
1001 
1002 static inline compat_uptr_t ptr_to_compat(void __user *uptr)
1003 {
1004 	return (u32)(unsigned long)uptr;
1005 }
1006 
1007 #endif /* _LINUX_COMPAT_H */
1008