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