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 32 #include <linux/uaccess.h> 33 #include <asm/utrap.h> 34 #include <asm/unistd.h> 35 36 #include "entry.h" 37 #include "kernel.h" 38 #include "systbls.h" 39 40 /* #define DEBUG_UNIMP_SYSCALL */ 41 42 SYSCALL_DEFINE0(getpagesize) 43 { 44 return PAGE_SIZE; 45 } 46 47 /* Does addr --> addr+len fall within 4GB of the VA-space hole or 48 * overflow past the end of the 64-bit address space? 49 */ 50 static inline int invalid_64bit_range(unsigned long addr, unsigned long len) 51 { 52 unsigned long va_exclude_start, va_exclude_end; 53 54 va_exclude_start = VA_EXCLUDE_START; 55 va_exclude_end = VA_EXCLUDE_END; 56 57 if (unlikely(len >= va_exclude_start)) 58 return 1; 59 60 if (unlikely((addr + len) < addr)) 61 return 1; 62 63 if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) || 64 ((addr + len) >= va_exclude_start && 65 (addr + len) < va_exclude_end))) 66 return 1; 67 68 return 0; 69 } 70 71 /* These functions differ from the default implementations in 72 * mm/mmap.c in two ways: 73 * 74 * 1) For file backed MAP_SHARED mmap()'s we D-cache color align, 75 * for fixed such mappings we just validate what the user gave us. 76 * 2) For 64-bit tasks we avoid mapping anything within 4GB of 77 * the spitfire/niagara VA-hole. 78 */ 79 80 static inline unsigned long COLOR_ALIGN(unsigned long addr, 81 unsigned long pgoff) 82 { 83 unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1); 84 unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1); 85 86 return base + off; 87 } 88 89 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) 90 { 91 struct mm_struct *mm = current->mm; 92 struct vm_area_struct * vma; 93 unsigned long task_size = TASK_SIZE; 94 int do_color_align; 95 struct vm_unmapped_area_info info; 96 97 if (flags & MAP_FIXED) { 98 /* We do not accept a shared mapping if it would violate 99 * cache aliasing constraints. 100 */ 101 if ((flags & MAP_SHARED) && 102 ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))) 103 return -EINVAL; 104 return addr; 105 } 106 107 if (test_thread_flag(TIF_32BIT)) 108 task_size = STACK_TOP32; 109 if (unlikely(len > task_size || len >= VA_EXCLUDE_START)) 110 return -ENOMEM; 111 112 do_color_align = 0; 113 if (filp || (flags & MAP_SHARED)) 114 do_color_align = 1; 115 116 if (addr) { 117 if (do_color_align) 118 addr = COLOR_ALIGN(addr, pgoff); 119 else 120 addr = PAGE_ALIGN(addr); 121 122 vma = find_vma(mm, addr); 123 if (task_size - len >= addr && 124 (!vma || addr + len <= vm_start_gap(vma))) 125 return addr; 126 } 127 128 info.flags = 0; 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 unsigned long (*get_area)(struct file *, unsigned long, 221 unsigned long, unsigned long, unsigned long); 222 223 get_area = current->mm->get_unmapped_area; 224 225 if (flags & MAP_FIXED) { 226 /* Ok, don't mess with it. */ 227 return get_area(NULL, orig_addr, len, pgoff, flags); 228 } 229 flags &= ~MAP_SHARED; 230 231 align_goal = PAGE_SIZE; 232 if (len >= (4UL * 1024 * 1024)) 233 align_goal = (4UL * 1024 * 1024); 234 else if (len >= (512UL * 1024)) 235 align_goal = (512UL * 1024); 236 else if (len >= (64UL * 1024)) 237 align_goal = (64UL * 1024); 238 239 do { 240 addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags); 241 if (!(addr & ~PAGE_MASK)) { 242 addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL); 243 break; 244 } 245 246 if (align_goal == (4UL * 1024 * 1024)) 247 align_goal = (512UL * 1024); 248 else if (align_goal == (512UL * 1024)) 249 align_goal = (64UL * 1024); 250 else 251 align_goal = PAGE_SIZE; 252 } while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE); 253 254 /* Mapping is smaller than 64K or larger areas could not 255 * be obtained. 256 */ 257 if (addr & ~PAGE_MASK) 258 addr = get_area(NULL, orig_addr, len, pgoff, flags); 259 260 return addr; 261 } 262 EXPORT_SYMBOL(get_fb_unmapped_area); 263 264 /* Essentially the same as PowerPC. */ 265 static unsigned long mmap_rnd(void) 266 { 267 unsigned long rnd = 0UL; 268 269 if (current->flags & PF_RANDOMIZE) { 270 unsigned long val = get_random_long(); 271 if (test_thread_flag(TIF_32BIT)) 272 rnd = (val % (1UL << (23UL-PAGE_SHIFT))); 273 else 274 rnd = (val % (1UL << (30UL-PAGE_SHIFT))); 275 } 276 return rnd << PAGE_SHIFT; 277 } 278 279 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) 280 { 281 unsigned long random_factor = mmap_rnd(); 282 unsigned long gap; 283 284 /* 285 * Fall back to the standard layout if the personality 286 * bit is set, or if the expected stack growth is unlimited: 287 */ 288 gap = rlim_stack->rlim_cur; 289 if (!test_thread_flag(TIF_32BIT) || 290 (current->personality & ADDR_COMPAT_LAYOUT) || 291 gap == RLIM_INFINITY || 292 sysctl_legacy_va_layout) { 293 mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; 294 mm->get_unmapped_area = arch_get_unmapped_area; 295 } else { 296 /* We know it's 32-bit */ 297 unsigned long task_size = STACK_TOP32; 298 299 if (gap < 128 * 1024 * 1024) 300 gap = 128 * 1024 * 1024; 301 if (gap > (task_size / 6 * 5)) 302 gap = (task_size / 6 * 5); 303 304 mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor); 305 mm->get_unmapped_area = arch_get_unmapped_area_topdown; 306 } 307 } 308 309 /* 310 * sys_pipe() is the normal C calling standard for creating 311 * a pipe. It's not the way unix traditionally does this, though. 312 */ 313 SYSCALL_DEFINE0(sparc_pipe) 314 { 315 int fd[2]; 316 int error; 317 318 error = do_pipe_flags(fd, 0); 319 if (error) 320 goto out; 321 current_pt_regs()->u_regs[UREG_I1] = fd[1]; 322 error = fd[0]; 323 out: 324 return error; 325 } 326 327 /* 328 * sys_ipc() is the de-multiplexer for the SysV IPC calls.. 329 * 330 * This is really horribly ugly. 331 */ 332 333 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second, 334 unsigned long, third, void __user *, ptr, long, fifth) 335 { 336 long err; 337 338 /* No need for backward compatibility. We can start fresh... */ 339 if (call <= SEMTIMEDOP) { 340 switch (call) { 341 case SEMOP: 342 err = sys_semtimedop(first, ptr, 343 (unsigned int)second, NULL); 344 goto out; 345 case SEMTIMEDOP: 346 err = sys_semtimedop(first, ptr, (unsigned int)second, 347 (const struct timespec __user *) 348 (unsigned long) fifth); 349 goto out; 350 case SEMGET: 351 err = sys_semget(first, (int)second, (int)third); 352 goto out; 353 case SEMCTL: { 354 err = sys_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 = sys_msgsnd(first, ptr, (size_t)second, 368 (int)third); 369 goto out; 370 case MSGRCV: 371 err = sys_msgrcv(first, ptr, (size_t)second, fifth, 372 (int)third); 373 goto out; 374 case MSGGET: 375 err = sys_msgget((key_t)first, (int)second); 376 goto out; 377 case MSGCTL: 378 err = sys_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 = sys_shmdt(ptr); 399 goto out; 400 case SHMGET: 401 err = sys_shmget(first, (size_t)second, (int)third); 402 goto out; 403 case SHMCTL: 404 err = sys_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, 0, current); 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_DEFINE5(utrap_install, utrap_entry_t, type, 548 utrap_handler_t, new_p, utrap_handler_t, new_d, 549 utrap_handler_t __user *, old_p, 550 utrap_handler_t __user *, old_d) 551 { 552 if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31) 553 return -EINVAL; 554 if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) { 555 if (old_p) { 556 if (!current_thread_info()->utraps) { 557 if (put_user(NULL, old_p)) 558 return -EFAULT; 559 } else { 560 if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p)) 561 return -EFAULT; 562 } 563 } 564 if (old_d) { 565 if (put_user(NULL, old_d)) 566 return -EFAULT; 567 } 568 return 0; 569 } 570 if (!current_thread_info()->utraps) { 571 current_thread_info()->utraps = 572 kcalloc(UT_TRAP_INSTRUCTION_31 + 1, sizeof(long), 573 GFP_KERNEL); 574 if (!current_thread_info()->utraps) 575 return -ENOMEM; 576 current_thread_info()->utraps[0] = 1; 577 } else { 578 if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p && 579 current_thread_info()->utraps[0] > 1) { 580 unsigned long *p = current_thread_info()->utraps; 581 582 current_thread_info()->utraps = 583 kmalloc_array(UT_TRAP_INSTRUCTION_31 + 1, 584 sizeof(long), 585 GFP_KERNEL); 586 if (!current_thread_info()->utraps) { 587 current_thread_info()->utraps = p; 588 return -ENOMEM; 589 } 590 p[0]--; 591 current_thread_info()->utraps[0] = 1; 592 memcpy(current_thread_info()->utraps+1, p+1, 593 UT_TRAP_INSTRUCTION_31*sizeof(long)); 594 } 595 } 596 if (old_p) { 597 if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p)) 598 return -EFAULT; 599 } 600 if (old_d) { 601 if (put_user(NULL, old_d)) 602 return -EFAULT; 603 } 604 current_thread_info()->utraps[type] = (long)new_p; 605 606 return 0; 607 } 608 609 SYSCALL_DEFINE1(memory_ordering, unsigned long, model) 610 { 611 struct pt_regs *regs = current_pt_regs(); 612 if (model >= 3) 613 return -EINVAL; 614 regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14); 615 return 0; 616 } 617 618 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act, 619 struct sigaction __user *, oact, void __user *, restorer, 620 size_t, sigsetsize) 621 { 622 struct k_sigaction new_ka, old_ka; 623 int ret; 624 625 /* XXX: Don't preclude handling different sized sigset_t's. */ 626 if (sigsetsize != sizeof(sigset_t)) 627 return -EINVAL; 628 629 if (act) { 630 new_ka.ka_restorer = restorer; 631 if (copy_from_user(&new_ka.sa, act, sizeof(*act))) 632 return -EFAULT; 633 } 634 635 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 636 637 if (!ret && oact) { 638 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact))) 639 return -EFAULT; 640 } 641 642 return ret; 643 } 644 645 SYSCALL_DEFINE0(kern_features) 646 { 647 return KERN_FEATURE_MIXED_MODE_STACK; 648 } 649