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