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