1// SPDX-License-Identifier: GPL-2.0
2/* linux/arch/sparc64/kernel/sys_sparc.c
3 *
4 * This file contains various random system calls that
5 * have a non-standard calling sequence on the Linux/sparc
6 * platform.
7 */
8
9#include <linux/errno.h>
10#include <linux/types.h>
11#include <linux/sched/signal.h>
12#include <linux/sched/mm.h>
13#include <linux/sched/debug.h>
14#include <linux/fs.h>
15#include <linux/file.h>
16#include <linux/mm.h>
17#include <linux/sem.h>
18#include <linux/msg.h>
19#include <linux/shm.h>
20#include <linux/stat.h>
21#include <linux/mman.h>
22#include <linux/utsname.h>
23#include <linux/smp.h>
24#include <linux/slab.h>
25#include <linux/syscalls.h>
26#include <linux/ipc.h>
27#include <linux/personality.h>
28#include <linux/random.h>
29#include <linux/export.h>
30#include <linux/context_tracking.h>
31#include <linux/timex.h>
32#include <linux/uaccess.h>
33
34#include <asm/utrap.h>
35#include <asm/unistd.h>
36
37#include "entry.h"
38#include "kernel.h"
39#include "systbls.h"
40
41/* #define DEBUG_UNIMP_SYSCALL */
42
43SYSCALL_DEFINE0(getpagesize)
44{
45	return PAGE_SIZE;
46}
47
48/* Does addr --> addr+len fall within 4GB of the VA-space hole or
49 * overflow past the end of the 64-bit address space?
50 */
51static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
52{
53	unsigned long va_exclude_start, va_exclude_end;
54
55	va_exclude_start = VA_EXCLUDE_START;
56	va_exclude_end   = VA_EXCLUDE_END;
57
58	if (unlikely(len >= va_exclude_start))
59		return 1;
60
61	if (unlikely((addr + len) < addr))
62		return 1;
63
64	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
65		     ((addr + len) >= va_exclude_start &&
66		      (addr + len) < va_exclude_end)))
67		return 1;
68
69	return 0;
70}
71
72/* These functions differ from the default implementations in
73 * mm/mmap.c in two ways:
74 *
75 * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
76 *    for fixed such mappings we just validate what the user gave us.
77 * 2) For 64-bit tasks we avoid mapping anything within 4GB of
78 *    the spitfire/niagara VA-hole.
79 */
80
81static inline unsigned long COLOR_ALIGN(unsigned long addr,
82					 unsigned long pgoff)
83{
84	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
85	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
86
87	return base + off;
88}
89
90unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
91{
92	struct mm_struct *mm = current->mm;
93	struct vm_area_struct * vma;
94	unsigned long task_size = TASK_SIZE;
95	int do_color_align;
96	struct vm_unmapped_area_info info;
97
98	if (flags & MAP_FIXED) {
99		/* We do not accept a shared mapping if it would violate
100		 * cache aliasing constraints.
101		 */
102		if ((flags & MAP_SHARED) &&
103		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
104			return -EINVAL;
105		return addr;
106	}
107
108	if (test_thread_flag(TIF_32BIT))
109		task_size = STACK_TOP32;
110	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
111		return -ENOMEM;
112
113	do_color_align = 0;
114	if (filp || (flags & MAP_SHARED))
115		do_color_align = 1;
116
117	if (addr) {
118		if (do_color_align)
119			addr = COLOR_ALIGN(addr, pgoff);
120		else
121			addr = PAGE_ALIGN(addr);
122
123		vma = find_vma(mm, addr);
124		if (task_size - len >= addr &&
125		    (!vma || addr + len <= vm_start_gap(vma)))
126			return addr;
127	}
128
129	info.flags = 0;
130	info.length = len;
131	info.low_limit = TASK_UNMAPPED_BASE;
132	info.high_limit = min(task_size, VA_EXCLUDE_START);
133	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
134	info.align_offset = pgoff << PAGE_SHIFT;
135	addr = vm_unmapped_area(&info);
136
137	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
138		VM_BUG_ON(addr != -ENOMEM);
139		info.low_limit = VA_EXCLUDE_END;
140		info.high_limit = task_size;
141		addr = vm_unmapped_area(&info);
142	}
143
144	return addr;
145}
146
147unsigned long
148arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
149			  const unsigned long len, const unsigned long pgoff,
150			  const unsigned long flags)
151{
152	struct vm_area_struct *vma;
153	struct mm_struct *mm = current->mm;
154	unsigned long task_size = STACK_TOP32;
155	unsigned long addr = addr0;
156	int do_color_align;
157	struct vm_unmapped_area_info info;
158
159	/* This should only ever run for 32-bit processes.  */
160	BUG_ON(!test_thread_flag(TIF_32BIT));
161
162	if (flags & MAP_FIXED) {
163		/* We do not accept a shared mapping if it would violate
164		 * cache aliasing constraints.
165		 */
166		if ((flags & MAP_SHARED) &&
167		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
168			return -EINVAL;
169		return addr;
170	}
171
172	if (unlikely(len > task_size))
173		return -ENOMEM;
174
175	do_color_align = 0;
176	if (filp || (flags & MAP_SHARED))
177		do_color_align = 1;
178
179	/* requesting a specific address */
180	if (addr) {
181		if (do_color_align)
182			addr = COLOR_ALIGN(addr, pgoff);
183		else
184			addr = PAGE_ALIGN(addr);
185
186		vma = find_vma(mm, addr);
187		if (task_size - len >= addr &&
188		    (!vma || addr + len <= vm_start_gap(vma)))
189			return addr;
190	}
191
192	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
193	info.length = len;
194	info.low_limit = PAGE_SIZE;
195	info.high_limit = mm->mmap_base;
196	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
197	info.align_offset = pgoff << PAGE_SHIFT;
198	addr = vm_unmapped_area(&info);
199
200	/*
201	 * A failed mmap() very likely causes application failure,
202	 * so fall back to the bottom-up function here. This scenario
203	 * can happen with large stack limits and large mmap()
204	 * allocations.
205	 */
206	if (addr & ~PAGE_MASK) {
207		VM_BUG_ON(addr != -ENOMEM);
208		info.flags = 0;
209		info.low_limit = TASK_UNMAPPED_BASE;
210		info.high_limit = STACK_TOP32;
211		addr = vm_unmapped_area(&info);
212	}
213
214	return addr;
215}
216
217/* Try to align mapping such that we align it as much as possible. */
218unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
219{
220	unsigned long align_goal, addr = -ENOMEM;
221	unsigned long (*get_area)(struct file *, unsigned long,
222				  unsigned long, unsigned long, unsigned long);
223
224	get_area = current->mm->get_unmapped_area;
225
226	if (flags & MAP_FIXED) {
227		/* Ok, don't mess with it. */
228		return get_area(NULL, orig_addr, len, pgoff, flags);
229	}
230	flags &= ~MAP_SHARED;
231
232	align_goal = PAGE_SIZE;
233	if (len >= (4UL * 1024 * 1024))
234		align_goal = (4UL * 1024 * 1024);
235	else if (len >= (512UL * 1024))
236		align_goal = (512UL * 1024);
237	else if (len >= (64UL * 1024))
238		align_goal = (64UL * 1024);
239
240	do {
241		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
242		if (!(addr & ~PAGE_MASK)) {
243			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
244			break;
245		}
246
247		if (align_goal == (4UL * 1024 * 1024))
248			align_goal = (512UL * 1024);
249		else if (align_goal == (512UL * 1024))
250			align_goal = (64UL * 1024);
251		else
252			align_goal = PAGE_SIZE;
253	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
254
255	/* Mapping is smaller than 64K or larger areas could not
256	 * be obtained.
257	 */
258	if (addr & ~PAGE_MASK)
259		addr = get_area(NULL, orig_addr, len, pgoff, flags);
260
261	return addr;
262}
263EXPORT_SYMBOL(get_fb_unmapped_area);
264
265/* Essentially the same as PowerPC.  */
266static unsigned long mmap_rnd(void)
267{
268	unsigned long rnd = 0UL;
269
270	if (current->flags & PF_RANDOMIZE) {
271		unsigned long val = get_random_long();
272		if (test_thread_flag(TIF_32BIT))
273			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
274		else
275			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
276	}
277	return rnd << PAGE_SHIFT;
278}
279
280void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
281{
282	unsigned long random_factor = mmap_rnd();
283	unsigned long gap;
284
285	/*
286	 * Fall back to the standard layout if the personality
287	 * bit is set, or if the expected stack growth is unlimited:
288	 */
289	gap = rlim_stack->rlim_cur;
290	if (!test_thread_flag(TIF_32BIT) ||
291	    (current->personality & ADDR_COMPAT_LAYOUT) ||
292	    gap == RLIM_INFINITY ||
293	    sysctl_legacy_va_layout) {
294		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
295		mm->get_unmapped_area = arch_get_unmapped_area;
296	} else {
297		/* We know it's 32-bit */
298		unsigned long task_size = STACK_TOP32;
299
300		if (gap < 128 * 1024 * 1024)
301			gap = 128 * 1024 * 1024;
302		if (gap > (task_size / 6 * 5))
303			gap = (task_size / 6 * 5);
304
305		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
306		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
307	}
308}
309
310/*
311 * sys_pipe() is the normal C calling standard for creating
312 * a pipe. It's not the way unix traditionally does this, though.
313 */
314SYSCALL_DEFINE0(sparc_pipe)
315{
316	int fd[2];
317	int error;
318
319	error = do_pipe_flags(fd, 0);
320	if (error)
321		goto out;
322	current_pt_regs()->u_regs[UREG_I1] = fd[1];
323	error = fd[0];
324out:
325	return error;
326}
327
328/*
329 * sys_ipc() is the de-multiplexer for the SysV IPC calls..
330 *
331 * This is really horribly ugly.
332 */
333
334SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
335		unsigned long, third, void __user *, ptr, long, fifth)
336{
337	long err;
338
339	if (!IS_ENABLED(CONFIG_SYSVIPC))
340		return -ENOSYS;
341
342	/* No need for backward compatibility. We can start fresh... */
343	if (call <= SEMTIMEDOP) {
344		switch (call) {
345		case SEMOP:
346			err = ksys_semtimedop(first, ptr,
347					      (unsigned int)second, NULL);
348			goto out;
349		case SEMTIMEDOP:
350			err = ksys_semtimedop(first, ptr, (unsigned int)second,
351				(const struct __kernel_timespec __user *)
352					      (unsigned long) fifth);
353			goto out;
354		case SEMGET:
355			err = ksys_semget(first, (int)second, (int)third);
356			goto out;
357		case SEMCTL: {
358			err = ksys_old_semctl(first, second,
359					      (int)third | IPC_64,
360					      (unsigned long) ptr);
361			goto out;
362		}
363		default:
364			err = -ENOSYS;
365			goto out;
366		}
367	}
368	if (call <= MSGCTL) {
369		switch (call) {
370		case MSGSND:
371			err = ksys_msgsnd(first, ptr, (size_t)second,
372					 (int)third);
373			goto out;
374		case MSGRCV:
375			err = ksys_msgrcv(first, ptr, (size_t)second, fifth,
376					 (int)third);
377			goto out;
378		case MSGGET:
379			err = ksys_msgget((key_t)first, (int)second);
380			goto out;
381		case MSGCTL:
382			err = ksys_old_msgctl(first, (int)second | IPC_64, ptr);
383			goto out;
384		default:
385			err = -ENOSYS;
386			goto out;
387		}
388	}
389	if (call <= SHMCTL) {
390		switch (call) {
391		case SHMAT: {
392			ulong raddr;
393			err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
394			if (!err) {
395				if (put_user(raddr,
396					     (ulong __user *) third))
397					err = -EFAULT;
398			}
399			goto out;
400		}
401		case SHMDT:
402			err = ksys_shmdt(ptr);
403			goto out;
404		case SHMGET:
405			err = ksys_shmget(first, (size_t)second, (int)third);
406			goto out;
407		case SHMCTL:
408			err = ksys_old_shmctl(first, (int)second | IPC_64, ptr);
409			goto out;
410		default:
411			err = -ENOSYS;
412			goto out;
413		}
414	} else {
415		err = -ENOSYS;
416	}
417out:
418	return err;
419}
420
421SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
422{
423	long ret;
424
425	if (personality(current->personality) == PER_LINUX32 &&
426	    personality(personality) == PER_LINUX)
427		personality |= PER_LINUX32;
428	ret = sys_personality(personality);
429	if (personality(ret) == PER_LINUX32)
430		ret &= ~PER_LINUX32;
431
432	return ret;
433}
434
435int sparc_mmap_check(unsigned long addr, unsigned long len)
436{
437	if (test_thread_flag(TIF_32BIT)) {
438		if (len >= STACK_TOP32)
439			return -EINVAL;
440
441		if (addr > STACK_TOP32 - len)
442			return -EINVAL;
443	} else {
444		if (len >= VA_EXCLUDE_START)
445			return -EINVAL;
446
447		if (invalid_64bit_range(addr, len))
448			return -EINVAL;
449	}
450
451	return 0;
452}
453
454/* Linux version of mmap */
455SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
456		unsigned long, prot, unsigned long, flags, unsigned long, fd,
457		unsigned long, off)
458{
459	unsigned long retval = -EINVAL;
460
461	if ((off + PAGE_ALIGN(len)) < off)
462		goto out;
463	if (off & ~PAGE_MASK)
464		goto out;
465	retval = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
466out:
467	return retval;
468}
469
470SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
471{
472	if (invalid_64bit_range(addr, len))
473		return -EINVAL;
474
475	return vm_munmap(addr, len);
476}
477
478SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
479		unsigned long, new_len, unsigned long, flags,
480		unsigned long, new_addr)
481{
482	if (test_thread_flag(TIF_32BIT))
483		return -EINVAL;
484	return sys_mremap(addr, old_len, new_len, flags, new_addr);
485}
486
487SYSCALL_DEFINE0(nis_syscall)
488{
489	static int count;
490	struct pt_regs *regs = current_pt_regs();
491
492	/* Don't make the system unusable, if someone goes stuck */
493	if (count++ > 5)
494		return -ENOSYS;
495
496	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
497#ifdef DEBUG_UNIMP_SYSCALL
498	show_regs (regs);
499#endif
500
501	return -ENOSYS;
502}
503
504/* #define DEBUG_SPARC_BREAKPOINT */
505
506asmlinkage void sparc_breakpoint(struct pt_regs *regs)
507{
508	enum ctx_state prev_state = exception_enter();
509
510	if (test_thread_flag(TIF_32BIT)) {
511		regs->tpc &= 0xffffffff;
512		regs->tnpc &= 0xffffffff;
513	}
514#ifdef DEBUG_SPARC_BREAKPOINT
515        printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
516#endif
517	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc);
518#ifdef DEBUG_SPARC_BREAKPOINT
519	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
520#endif
521	exception_exit(prev_state);
522}
523
524SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
525{
526	int nlen, err;
527	char tmp[__NEW_UTS_LEN + 1];
528
529	if (len < 0)
530		return -EINVAL;
531
532	down_read(&uts_sem);
533
534	nlen = strlen(utsname()->domainname) + 1;
535	err = -EINVAL;
536	if (nlen > len)
537		goto out_unlock;
538	memcpy(tmp, utsname()->domainname, nlen);
539
540	up_read(&uts_sem);
541
542	if (copy_to_user(name, tmp, nlen))
543		return -EFAULT;
544	return 0;
545
546out_unlock:
547	up_read(&uts_sem);
548	return err;
549}
550
551SYSCALL_DEFINE1(sparc_adjtimex, struct __kernel_timex __user *, txc_p)
552{
553	struct __kernel_timex txc;
554	struct __kernel_old_timeval *tv = (void *)&txc.time;
555	int ret;
556
557	/* Copy the user data space into the kernel copy
558	 * structure. But bear in mind that the structures
559	 * may change
560	 */
561	if (copy_from_user(&txc, txc_p, sizeof(txc)))
562		return -EFAULT;
563
564	/*
565	 * override for sparc64 specific timeval type: tv_usec
566	 * is 32 bit wide instead of 64-bit in __kernel_timex
567	 */
568	txc.time.tv_usec = tv->tv_usec;
569	ret = do_adjtimex(&txc);
570	tv->tv_usec = txc.time.tv_usec;
571
572	return copy_to_user(txc_p, &txc, sizeof(txc)) ? -EFAULT : ret;
573}
574
575SYSCALL_DEFINE2(sparc_clock_adjtime, const clockid_t, which_clock,
576		struct __kernel_timex __user *, txc_p)
577{
578	struct __kernel_timex txc;
579	struct __kernel_old_timeval *tv = (void *)&txc.time;
580	int ret;
581
582	if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) {
583		pr_err_once("process %d (%s) attempted a POSIX timer syscall "
584		    "while CONFIG_POSIX_TIMERS is not set\n",
585		    current->pid, current->comm);
586
587		return -ENOSYS;
588	}
589
590	/* Copy the user data space into the kernel copy
591	 * structure. But bear in mind that the structures
592	 * may change
593	 */
594	if (copy_from_user(&txc, txc_p, sizeof(txc)))
595		return -EFAULT;
596
597	/*
598	 * override for sparc64 specific timeval type: tv_usec
599	 * is 32 bit wide instead of 64-bit in __kernel_timex
600	 */
601	txc.time.tv_usec = tv->tv_usec;
602	ret = do_clock_adjtime(which_clock, &txc);
603	tv->tv_usec = txc.time.tv_usec;
604
605	return copy_to_user(txc_p, &txc, sizeof(txc)) ? -EFAULT : ret;
606}
607
608SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
609		utrap_handler_t, new_p, utrap_handler_t, new_d,
610		utrap_handler_t __user *, old_p,
611		utrap_handler_t __user *, old_d)
612{
613	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
614		return -EINVAL;
615	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
616		if (old_p) {
617			if (!current_thread_info()->utraps) {
618				if (put_user(NULL, old_p))
619					return -EFAULT;
620			} else {
621				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
622					return -EFAULT;
623			}
624		}
625		if (old_d) {
626			if (put_user(NULL, old_d))
627				return -EFAULT;
628		}
629		return 0;
630	}
631	if (!current_thread_info()->utraps) {
632		current_thread_info()->utraps =
633			kcalloc(UT_TRAP_INSTRUCTION_31 + 1, sizeof(long),
634				GFP_KERNEL);
635		if (!current_thread_info()->utraps)
636			return -ENOMEM;
637		current_thread_info()->utraps[0] = 1;
638	} else {
639		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
640		    current_thread_info()->utraps[0] > 1) {
641			unsigned long *p = current_thread_info()->utraps;
642
643			current_thread_info()->utraps =
644				kmalloc_array(UT_TRAP_INSTRUCTION_31 + 1,
645					      sizeof(long),
646					      GFP_KERNEL);
647			if (!current_thread_info()->utraps) {
648				current_thread_info()->utraps = p;
649				return -ENOMEM;
650			}
651			p[0]--;
652			current_thread_info()->utraps[0] = 1;
653			memcpy(current_thread_info()->utraps+1, p+1,
654			       UT_TRAP_INSTRUCTION_31*sizeof(long));
655		}
656	}
657	if (old_p) {
658		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
659			return -EFAULT;
660	}
661	if (old_d) {
662		if (put_user(NULL, old_d))
663			return -EFAULT;
664	}
665	current_thread_info()->utraps[type] = (long)new_p;
666
667	return 0;
668}
669
670SYSCALL_DEFINE1(memory_ordering, unsigned long, model)
671{
672	struct pt_regs *regs = current_pt_regs();
673	if (model >= 3)
674		return -EINVAL;
675	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
676	return 0;
677}
678
679SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
680		struct sigaction __user *, oact, void __user *, restorer,
681		size_t, sigsetsize)
682{
683	struct k_sigaction new_ka, old_ka;
684	int ret;
685
686	/* XXX: Don't preclude handling different sized sigset_t's.  */
687	if (sigsetsize != sizeof(sigset_t))
688		return -EINVAL;
689
690	if (act) {
691		new_ka.ka_restorer = restorer;
692		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
693			return -EFAULT;
694	}
695
696	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
697
698	if (!ret && oact) {
699		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
700			return -EFAULT;
701	}
702
703	return ret;
704}
705
706SYSCALL_DEFINE0(kern_features)
707{
708	return KERN_FEATURE_MIXED_MODE_STACK;
709}
710