arch/parisc/kernel/sys_parisc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 /*
   4  *    PARISC specific syscalls
   5  *
   6  *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
   7  *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
   8  *    Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
   9  *    Copyright (C) 1999-2020 Helge Deller <deller@gmx.de>
  10  */
  11
  12 #include <linux/uaccess.h>
  13 #include <asm/elf.h>
  14 #include <linux/file.h>
  15 #include <linux/fs.h>
  16 #include <linux/linkage.h>
  17 #include <linux/mm.h>
  18 #include <linux/mman.h>
  19 #include <linux/sched/signal.h>
  20 #include <linux/sched/mm.h>
  21 #include <linux/shm.h>
  22 #include <linux/syscalls.h>
  23 #include <linux/utsname.h>
  24 #include <linux/personality.h>
  25 #include <linux/random.h>
  26 #include <linux/compat.h>
  27
  28 /* we construct an artificial offset for the mapping based on the physical
  29  * address of the kernel mapping variable */
  30 #define GET_LAST_MMAP(filp)             \
  31         (filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
  32 #define SET_LAST_MMAP(filp, val)        \
  33          { /* nothing */ }
  34
  35 static int get_offset(unsigned int last_mmap)
  36 {
  37         return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
  38 }
  39
  40 static unsigned long shared_align_offset(unsigned int last_mmap,
  41                                          unsigned long pgoff)
  42 {
  43         return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
  44 }
  45
  46 static inline unsigned long COLOR_ALIGN(unsigned long addr,
  47                          unsigned int last_mmap, unsigned long pgoff)
  48 {
  49         unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
  50         unsigned long off  = (SHM_COLOUR-1) &
  51                 (shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
  52
  53         return base + off;
  54 }
  55
  56
  57 #define STACK_SIZE_DEFAULT (USER_WIDE_MODE                      \
  58                         ? (1 << 30)     /* 1 GB */              \
  59                         : (CONFIG_STACK_MAX_DEFAULT_SIZE_MB*1024*1024))
  60
  61 unsigned long calc_max_stack_size(unsigned long stack_max)
  62 {
  63 #ifdef CONFIG_COMPAT
  64         if (!USER_WIDE_MODE && (stack_max == COMPAT_RLIM_INFINITY))
  65                 stack_max = STACK_SIZE_DEFAULT;
  66         else
  67 #endif
  68         if (stack_max == RLIM_INFINITY)
  69                 stack_max = STACK_SIZE_DEFAULT;
  70
  71         return stack_max;
  72 }
  73
  74
  75 /*
  76  * Top of mmap area (just below the process stack).
  77  */
  78
  79 /*
  80  * When called from arch_get_unmapped_area(), rlim_stack will be NULL,
  81  * indicating that "current" should be used instead of a passed-in
  82  * value from the exec bprm as done with arch_pick_mmap_layout().
  83  */
  84 static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
  85 {
  86         unsigned long stack_base;
  87
  88         /* Limit stack size - see setup_arg_pages() in fs/exec.c */
  89         stack_base = rlim_stack ? rlim_stack->rlim_max
  90                                 : rlimit_max(RLIMIT_STACK);
  91
  92         stack_base = calc_max_stack_size(stack_base);
  93
  94         /* Add space for stack randomization. */
  95         if (current->flags & PF_RANDOMIZE)
  96                 stack_base += (STACK_RND_MASK << PAGE_SHIFT);
  97
  98         return PAGE_ALIGN(STACK_TOP - stack_base);
  99 }
 100
 101
 102 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 103                 unsigned long len, unsigned long pgoff, unsigned long flags)
 104 {
 105         struct mm_struct *mm = current->mm;
 106         struct vm_area_struct *vma, *prev;
 107         unsigned long task_size = TASK_SIZE;
 108         int do_color_align, last_mmap;
 109         struct vm_unmapped_area_info info;
 110
 111         if (len > task_size)
 112                 return -ENOMEM;
 113
 114         do_color_align = 0;
 115         if (filp || (flags & MAP_SHARED))
 116                 do_color_align = 1;
 117         last_mmap = GET_LAST_MMAP(filp);
 118
 119         if (flags & MAP_FIXED) {
 120                 if ((flags & MAP_SHARED) && last_mmap &&
 121                     (addr - shared_align_offset(last_mmap, pgoff))
 122                                 & (SHM_COLOUR - 1))
 123                         return -EINVAL;
 124                 goto found_addr;
 125         }
 126
 127         if (addr) {
 128                 if (do_color_align && last_mmap)
 129                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 130                 else
 131                         addr = PAGE_ALIGN(addr);
 132
 133                 vma = find_vma_prev(mm, addr, &prev);
 134                 if (task_size - len >= addr &&
 135                     (!vma || addr + len <= vm_start_gap(vma)) &&
 136                     (!prev || addr >= vm_end_gap(prev)))
 137                         goto found_addr;
 138         }
 139
 140         info.flags = 0;
 141         info.length = len;
 142         info.low_limit = mm->mmap_legacy_base;
 143         info.high_limit = mmap_upper_limit(NULL);
 144         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 145         info.align_offset = shared_align_offset(last_mmap, pgoff);
 146         addr = vm_unmapped_area(&info);
 147
 148 found_addr:
 149         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 150                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 151
 152         return addr;
 153 }
 154
 155 unsigned long
 156 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 157                           const unsigned long len, const unsigned long pgoff,
 158                           const unsigned long flags)
 159 {
 160         struct vm_area_struct *vma, *prev;
 161         struct mm_struct *mm = current->mm;
 162         unsigned long addr = addr0;
 163         int do_color_align, last_mmap;
 164         struct vm_unmapped_area_info info;
 165
 166         /* requested length too big for entire address space */
 167         if (len > TASK_SIZE)
 168                 return -ENOMEM;
 169
 170         do_color_align = 0;
 171         if (filp || (flags & MAP_SHARED))
 172                 do_color_align = 1;
 173         last_mmap = GET_LAST_MMAP(filp);
 174
 175         if (flags & MAP_FIXED) {
 176                 if ((flags & MAP_SHARED) && last_mmap &&
 177                     (addr - shared_align_offset(last_mmap, pgoff))
 178                         & (SHM_COLOUR - 1))
 179                         return -EINVAL;
 180                 goto found_addr;
 181         }
 182
 183         /* requesting a specific address */
 184         if (addr) {
 185                 if (do_color_align && last_mmap)
 186                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 187                 else
 188                         addr = PAGE_ALIGN(addr);
 189
 190                 vma = find_vma_prev(mm, addr, &prev);
 191                 if (TASK_SIZE - len >= addr &&
 192                     (!vma || addr + len <= vm_start_gap(vma)) &&
 193                     (!prev || addr >= vm_end_gap(prev)))
 194                         goto found_addr;
 195         }
 196
 197         info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 198         info.length = len;
 199         info.low_limit = PAGE_SIZE;
 200         info.high_limit = mm->mmap_base;
 201         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 202         info.align_offset = shared_align_offset(last_mmap, pgoff);
 203         addr = vm_unmapped_area(&info);
 204         if (!(addr & ~PAGE_MASK))
 205                 goto found_addr;
 206         VM_BUG_ON(addr != -ENOMEM);
 207
 208         /*
 209          * A failed mmap() very likely causes application failure,
 210          * so fall back to the bottom-up function here. This scenario
 211          * can happen with large stack limits and large mmap()
 212          * allocations.
 213          */
 214         return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
 215
 216 found_addr:
 217         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 218                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 219
 220         return addr;
 221 }
 222
 223 static int mmap_is_legacy(void)
 224 {
 225         if (current->personality & ADDR_COMPAT_LAYOUT)
 226                 return 1;
 227
 228         /* parisc stack always grows up - so a unlimited stack should
 229          * not be an indicator to use the legacy memory layout.
 230          * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
 231          *      return 1;
 232          */
 233
 234         return sysctl_legacy_va_layout;
 235 }
 236
 237 static unsigned long mmap_rnd(void)
 238 {
 239         unsigned long rnd = 0;
 240
 241         if (current->flags & PF_RANDOMIZE)
 242                 rnd = get_random_int() & MMAP_RND_MASK;
 243
 244         return rnd << PAGE_SHIFT;
 245 }
 246
 247 unsigned long arch_mmap_rnd(void)
 248 {
 249         return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
 250 }
 251
 252 static unsigned long mmap_legacy_base(void)
 253 {
 254         return TASK_UNMAPPED_BASE + mmap_rnd();
 255 }
 256
 257 /*
 258  * This function, called very early during the creation of a new
 259  * process VM image, sets up which VM layout function to use:
 260  */
 261 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 262 {
 263         mm->mmap_legacy_base = mmap_legacy_base();
 264         mm->mmap_base = mmap_upper_limit(rlim_stack);
 265
 266         if (mmap_is_legacy()) {
 267                 mm->mmap_base = mm->mmap_legacy_base;
 268                 mm->get_unmapped_area = arch_get_unmapped_area;
 269         } else {
 270                 mm->get_unmapped_area = arch_get_unmapped_area_topdown;
 271         }
 272 }
 273
 274
 275 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 276         unsigned long prot, unsigned long flags, unsigned long fd,
 277         unsigned long pgoff)
 278 {
 279         /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 280            we have. */
 281         return ksys_mmap_pgoff(addr, len, prot, flags, fd,
 282                                pgoff >> (PAGE_SHIFT - 12));
 283 }
 284
 285 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 286                 unsigned long prot, unsigned long flags, unsigned long fd,
 287                 unsigned long offset)
 288 {
 289         if (!(offset & ~PAGE_MASK)) {
 290                 return ksys_mmap_pgoff(addr, len, prot, flags, fd,
 291                                         offset >> PAGE_SHIFT);
 292         } else {
 293                 return -EINVAL;
 294         }
 295 }
 296
 297 /* Fucking broken ABI */
 298
 299 #ifdef CONFIG_64BIT
 300 asmlinkage long parisc_truncate64(const char __user * path,
 301                                         unsigned int high, unsigned int low)
 302 {
 303         return ksys_truncate(path, (long)high << 32 | low);
 304 }
 305
 306 asmlinkage long parisc_ftruncate64(unsigned int fd,
 307                                         unsigned int high, unsigned int low)
 308 {
 309         return ksys_ftruncate(fd, (long)high << 32 | low);
 310 }
 311
 312 /* stubs for the benefit of the syscall_table since truncate64 and truncate
 313  * are identical on LP64 */
 314 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
 315 {
 316         return ksys_truncate(path, length);
 317 }
 318 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
 319 {
 320         return ksys_ftruncate(fd, length);
 321 }
 322 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
 323 {
 324         return sys_fcntl(fd, cmd, arg);
 325 }
 326 #else
 327
 328 asmlinkage long parisc_truncate64(const char __user * path,
 329                                         unsigned int high, unsigned int low)
 330 {
 331         return ksys_truncate(path, (loff_t)high << 32 | low);
 332 }
 333
 334 asmlinkage long parisc_ftruncate64(unsigned int fd,
 335                                         unsigned int high, unsigned int low)
 336 {
 337         return sys_ftruncate64(fd, (loff_t)high << 32 | low);
 338 }
 339 #endif
 340
 341 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
 342                                         unsigned int high, unsigned int low)
 343 {
 344         return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);
 345 }
 346
 347 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
 348                         size_t count, unsigned int high, unsigned int low)
 349 {
 350         return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
 351 }
 352
 353 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
 354                                     size_t count)
 355 {
 356         return ksys_readahead(fd, (loff_t)high << 32 | low, count);
 357 }
 358
 359 asmlinkage long parisc_fadvise64_64(int fd,
 360                         unsigned int high_off, unsigned int low_off,
 361                         unsigned int high_len, unsigned int low_len, int advice)
 362 {
 363         return ksys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
 364                         (loff_t)high_len << 32 | low_len, advice);
 365 }
 366
 367 asmlinkage long parisc_sync_file_range(int fd,
 368                         u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
 369                         unsigned int flags)
 370 {
 371         return ksys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
 372                         (loff_t)hi_nbytes << 32 | lo_nbytes, flags);
 373 }
 374
 375 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
 376                                 u32 lenhi, u32 lenlo)
 377 {
 378         return ksys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
 379                               ((u64)lenhi << 32) | lenlo);
 380 }
 381
 382 long parisc_personality(unsigned long personality)
 383 {
 384         long err;
 385
 386         if (personality(current->personality) == PER_LINUX32
 387             && personality(personality) == PER_LINUX)
 388                 personality = (personality & ~PER_MASK) | PER_LINUX32;
 389
 390         err = sys_personality(personality);
 391         if (personality(err) == PER_LINUX32)
 392                 err = (err & ~PER_MASK) | PER_LINUX;
 393
 394         return err;
 395 }
 396
 397 /*
 398  * Up to kernel v5.9 we defined O_NONBLOCK as 000200004,
 399  * since then O_NONBLOCK is defined as 000200000.
 400  *
 401  * The following wrapper functions mask out the old
 402  * O_NDELAY bit from calls which use O_NONBLOCK.
 403  *
 404  * XXX: Remove those in year 2022 (or later)?
 405  */
 406
 407 #define O_NONBLOCK_OLD          000200004
 408 #define O_NONBLOCK_MASK_OUT     (O_NONBLOCK_OLD & ~O_NONBLOCK)
 409
 410 static int FIX_O_NONBLOCK(int flags)
 411 {
 412         if (flags & O_NONBLOCK_MASK_OUT) {
 413                 struct task_struct *tsk = current;
 414                 pr_warn_once("%s(%d) uses a deprecated O_NONBLOCK value.\n",
 415                         tsk->comm, tsk->pid);
 416         }
 417         return flags & ~O_NONBLOCK_MASK_OUT;
 418 }
 419
 420 asmlinkage long parisc_timerfd_create(int clockid, int flags)
 421 {
 422         flags = FIX_O_NONBLOCK(flags);
 423         return sys_timerfd_create(clockid, flags);
 424 }
 425
 426 asmlinkage long parisc_signalfd4(int ufd, sigset_t __user *user_mask,
 427         size_t sizemask, int flags)
 428 {
 429         flags = FIX_O_NONBLOCK(flags);
 430         return sys_signalfd4(ufd, user_mask, sizemask, flags);
 431 }
 432
 433 #ifdef CONFIG_COMPAT
 434 asmlinkage long parisc_compat_signalfd4(int ufd,
 435         compat_sigset_t __user *user_mask,
 436         compat_size_t sizemask, int flags)
 437 {
 438         flags = FIX_O_NONBLOCK(flags);
 439         return compat_sys_signalfd4(ufd, user_mask, sizemask, flags);
 440 }
 441 #endif
 442
 443 asmlinkage long parisc_eventfd2(unsigned int count, int flags)
 444 {
 445         flags = FIX_O_NONBLOCK(flags);
 446         return sys_eventfd2(count, flags);
 447 }
 448
 449 asmlinkage long parisc_userfaultfd(int flags)
 450 {
 451         flags = FIX_O_NONBLOCK(flags);
 452         return sys_userfaultfd(flags);
 453 }
 454
 455 asmlinkage long parisc_pipe2(int __user *fildes, int flags)
 456 {
 457         flags = FIX_O_NONBLOCK(flags);
 458         return sys_pipe2(fildes, flags);
 459 }
 460
 461 asmlinkage long parisc_inotify_init1(int flags)
 462 {
 463         flags = FIX_O_NONBLOCK(flags);
 464         return sys_inotify_init1(flags);
 465 }