libio/vtables.c

   1 /* libio vtable validation.
   2    Copyright (C) 2016-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <dlfcn.h>
  20 #include <libioP.h>
  21 #include <stdio.h>
  22 #include <ldsodefs.h>
  23 #include <pointer_guard.h>
  24 #include <libio-macros.h>
  25
  26 /* Both _IO_str_* and _IO_new_file functions are pulled into every link (from
  27    stdio initialization).  */
  28 #ifndef SHARED
  29 /* NB: the following directives do add pragma weak for _IO_default _* and
  30    _IO_wdefault_* symbols to potentially avoid link failures, since they
  31    are always used when the __io_vtables is used.  */
  32 # pragma weak _IO_wstr_finish
  33 # pragma weak _IO_wstr_overflow
  34 # pragma weak _IO_wstr_pbackfail
  35 # pragma weak _IO_wstr_seekoff
  36 # pragma weak _IO_wstr_underflow
  37
  38 # pragma weak _IO_file_close
  39 # pragma weak _IO_file_close_mmap
  40 # pragma weak _IO_file_doallocate
  41 # pragma weak _IO_file_finish
  42 # pragma weak _IO_file_jumps_alias
  43 # pragma weak _IO_file_overflow
  44 # pragma weak _IO_file_read
  45 # pragma weak _IO_file_seek
  46 # pragma weak _IO_file_seekoff_maybe_mmap
  47 # pragma weak _IO_file_seekoff_mmap
  48 # pragma weak _IO_file_setbuf
  49 # pragma weak _IO_file_setbuf_mmap
  50 # pragma weak _IO_file_setbuf_mmap
  51 # pragma weak _IO_file_stat
  52 # pragma weak _IO_file_sync
  53 # pragma weak _IO_file_sync_mmap
  54 # pragma weak _IO_file_underflow
  55 # pragma weak _IO_file_underflow_maybe_mmap
  56 # pragma weak _IO_file_underflow_mmap
  57 # pragma weak _IO_file_xsgetn
  58 # pragma weak _IO_file_xsgetn_maybe_mmap
  59 # pragma weak _IO_file_xsgetn_mmap
  60 # pragma weak _IO_file_xsputn
  61
  62 # pragma weak _IO_wfile_overflow
  63 # pragma weak _IO_wfile_sync
  64 # pragma weak _IO_wfile_underflow
  65 # pragma weak _IO_wfile_underflow_maybe_mmap
  66 # pragma weak _IO_wfile_underflow_mmap
  67 # pragma weak _IO_wfile_doallocate
  68 # pragma weak _IO_wfile_jumps_alia
  69 # pragma weak _IO_wfile_seekoff
  70 # pragma weak _IO_wfile_xsputn
  71
  72 # pragma weak _IO_new_proc_close
  73
  74 # pragma weak _IO_cookie_close
  75 # pragma weak _IO_cookie_read
  76 # pragma weak _IO_cookie_seek
  77 # pragma weak _IO_cookie_seekoff
  78 # pragma weak _IO_cookie_write
  79
  80 # pragma weak _IO_mem_finish
  81 # pragma weak _IO_mem_sync
  82
  83 # pragma weak _IO_wmem_finish
  84 # pragma weak _IO_wmem_sync
  85
  86 # pragma weak __printf_buffer_as_file_overflow
  87 # pragma weak __printf_buffer_as_file_xsputn
  88
  89 # pragma weak __wprintf_buffer_as_file_overflow
  90 # pragma weak __wprintf_buffer_as_file_xsputn
  91 #endif
  92
  93 const struct _IO_jump_t __io_vtables[IO_VTABLES_LEN] attribute_relro =
  94 {
  95   /* _IO_str_jumps  */
  96   [IO_STR_JUMPS] =
  97   {
  98     JUMP_INIT_DUMMY,
  99     JUMP_INIT (finish, _IO_str_finish),
 100     JUMP_INIT (overflow, _IO_str_overflow),
 101     JUMP_INIT (underflow, _IO_str_underflow),
 102     JUMP_INIT (uflow, _IO_default_uflow),
 103     JUMP_INIT (pbackfail, _IO_str_pbackfail),
 104     JUMP_INIT (xsputn, _IO_default_xsputn),
 105     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 106     JUMP_INIT (seekoff, _IO_str_seekoff),
 107     JUMP_INIT (seekpos, _IO_default_seekpos),
 108     JUMP_INIT (setbuf, _IO_default_setbuf),
 109     JUMP_INIT (sync, _IO_default_sync),
 110     JUMP_INIT (doallocate, _IO_default_doallocate),
 111     JUMP_INIT (read, _IO_default_read),
 112     JUMP_INIT (write, _IO_default_write),
 113     JUMP_INIT (seek, _IO_default_seek),
 114     JUMP_INIT (close, _IO_default_close),
 115     JUMP_INIT (stat, _IO_default_stat),
 116     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 117     JUMP_INIT (imbue, _IO_default_imbue)
 118   },
 119   /* _IO_wstr_jumps  */
 120   [IO_WSTR_JUMPS] = {
 121     JUMP_INIT_DUMMY,
 122     JUMP_INIT (finish, _IO_wstr_finish),
 123     JUMP_INIT (overflow, (_IO_overflow_t) _IO_wstr_overflow),
 124     JUMP_INIT (underflow, (_IO_underflow_t) _IO_wstr_underflow),
 125     JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
 126     JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wstr_pbackfail),
 127     JUMP_INIT (xsputn, _IO_wdefault_xsputn),
 128     JUMP_INIT (xsgetn, _IO_wdefault_xsgetn),
 129     JUMP_INIT (seekoff, _IO_wstr_seekoff),
 130     JUMP_INIT (seekpos, _IO_default_seekpos),
 131     JUMP_INIT (setbuf, _IO_default_setbuf),
 132     JUMP_INIT (sync, _IO_default_sync),
 133     JUMP_INIT (doallocate, _IO_wdefault_doallocate),
 134     JUMP_INIT (read, _IO_default_read),
 135     JUMP_INIT (write, _IO_default_write),
 136     JUMP_INIT (seek, _IO_default_seek),
 137     JUMP_INIT (close, _IO_default_close),
 138     JUMP_INIT (stat, _IO_default_stat),
 139     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 140     JUMP_INIT (imbue, _IO_default_imbue)
 141   },
 142   /* _IO_file_jumps  */
 143   [IO_FILE_JUMPS] = {
 144     JUMP_INIT_DUMMY,
 145     JUMP_INIT (finish, _IO_file_finish),
 146     JUMP_INIT (overflow, _IO_file_overflow),
 147     JUMP_INIT (underflow, _IO_file_underflow),
 148     JUMP_INIT (uflow, _IO_default_uflow),
 149     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 150     JUMP_INIT (xsputn, _IO_file_xsputn),
 151     JUMP_INIT (xsgetn, _IO_file_xsgetn),
 152     JUMP_INIT (seekoff, _IO_new_file_seekoff),
 153     JUMP_INIT (seekpos, _IO_default_seekpos),
 154     JUMP_INIT (setbuf, _IO_new_file_setbuf),
 155     JUMP_INIT (sync, _IO_new_file_sync),
 156     JUMP_INIT (doallocate, _IO_file_doallocate),
 157     JUMP_INIT (read, _IO_file_read),
 158     JUMP_INIT (write, _IO_new_file_write),
 159     JUMP_INIT (seek, _IO_file_seek),
 160     JUMP_INIT (close, _IO_file_close),
 161     JUMP_INIT (stat, _IO_file_stat),
 162     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 163     JUMP_INIT (imbue, _IO_default_imbue)
 164   },
 165   /* _IO_file_jumps_mmap  */
 166   [IO_FILE_JUMPS_MMAP] = {
 167     JUMP_INIT_DUMMY,
 168     JUMP_INIT (finish, _IO_file_finish),
 169     JUMP_INIT (overflow, _IO_file_overflow),
 170     JUMP_INIT (underflow, _IO_file_underflow_mmap),
 171     JUMP_INIT (uflow, _IO_default_uflow),
 172     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 173     JUMP_INIT (xsputn, _IO_new_file_xsputn),
 174     JUMP_INIT (xsgetn, _IO_file_xsgetn_mmap),
 175     JUMP_INIT (seekoff, _IO_file_seekoff_mmap),
 176     JUMP_INIT (seekpos, _IO_default_seekpos),
 177     JUMP_INIT (setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
 178     JUMP_INIT (sync, _IO_file_sync_mmap),
 179     JUMP_INIT (doallocate, _IO_file_doallocate),
 180     JUMP_INIT (read, _IO_file_read),
 181     JUMP_INIT (write, _IO_new_file_write),
 182     JUMP_INIT (seek, _IO_file_seek),
 183     JUMP_INIT (close, _IO_file_close_mmap),
 184     JUMP_INIT (stat, _IO_file_stat),
 185     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 186     JUMP_INIT (imbue, _IO_default_imbue)
 187   },
 188   /* _IO_file_jumps_maybe_mmap  */
 189   [IO_FILE_JUMPS_MAYBE_MMAP] = {
 190     JUMP_INIT_DUMMY,
 191     JUMP_INIT (finish, _IO_file_finish),
 192     JUMP_INIT (overflow, _IO_file_overflow),
 193     JUMP_INIT (underflow, _IO_file_underflow_maybe_mmap),
 194     JUMP_INIT (uflow, _IO_default_uflow),
 195     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 196     JUMP_INIT (xsputn, _IO_new_file_xsputn),
 197     JUMP_INIT (xsgetn, _IO_file_xsgetn_maybe_mmap),
 198     JUMP_INIT (seekoff, _IO_file_seekoff_maybe_mmap),
 199     JUMP_INIT (seekpos, _IO_default_seekpos),
 200     JUMP_INIT (setbuf, (_IO_setbuf_t) _IO_file_setbuf_mmap),
 201     JUMP_INIT (sync, _IO_new_file_sync),
 202     JUMP_INIT (doallocate, _IO_file_doallocate),
 203     JUMP_INIT (read, _IO_file_read),
 204     JUMP_INIT (write, _IO_new_file_write),
 205     JUMP_INIT (seek, _IO_file_seek),
 206     JUMP_INIT (close, _IO_file_close),
 207     JUMP_INIT (stat, _IO_file_stat),
 208     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 209     JUMP_INIT (imbue, _IO_default_imbue)
 210   },
 211   /* _IO_wfile_jumps  */
 212   [IO_WFILE_JUMPS] = {
 213     JUMP_INIT_DUMMY,
 214     JUMP_INIT (finish, _IO_new_file_finish),
 215     JUMP_INIT (overflow, (_IO_overflow_t) _IO_wfile_overflow),
 216     JUMP_INIT (underflow, (_IO_underflow_t) _IO_wfile_underflow),
 217     JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
 218     JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wdefault_pbackfail),
 219     JUMP_INIT (xsputn, _IO_wfile_xsputn),
 220     JUMP_INIT (xsgetn, _IO_file_xsgetn),
 221     JUMP_INIT (seekoff, _IO_wfile_seekoff),
 222     JUMP_INIT (seekpos, _IO_default_seekpos),
 223     JUMP_INIT (setbuf, _IO_new_file_setbuf),
 224     JUMP_INIT (sync, (_IO_sync_t) _IO_wfile_sync),
 225     JUMP_INIT (doallocate, _IO_wfile_doallocate),
 226     JUMP_INIT (read, _IO_file_read),
 227     JUMP_INIT (write, _IO_new_file_write),
 228     JUMP_INIT (seek, _IO_file_seek),
 229     JUMP_INIT (close, _IO_file_close),
 230     JUMP_INIT (stat, _IO_file_stat),
 231     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 232     JUMP_INIT (imbue, _IO_default_imbue)
 233   },
 234   /* _IO_wfile_jumps_mmap  */
 235   [IO_WFILE_JUMPS_MMAP] = {
 236     JUMP_INIT_DUMMY,
 237     JUMP_INIT (finish, _IO_new_file_finish),
 238     JUMP_INIT (overflow, (_IO_overflow_t) _IO_wfile_overflow),
 239     JUMP_INIT (underflow, (_IO_underflow_t) _IO_wfile_underflow_mmap),
 240     JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
 241     JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wdefault_pbackfail),
 242     JUMP_INIT (xsputn, _IO_wfile_xsputn),
 243     JUMP_INIT (xsgetn, _IO_file_xsgetn),
 244     JUMP_INIT (seekoff, _IO_wfile_seekoff),
 245     JUMP_INIT (seekpos, _IO_default_seekpos),
 246     JUMP_INIT (setbuf, _IO_file_setbuf_mmap),
 247     JUMP_INIT (sync, (_IO_sync_t) _IO_wfile_sync),
 248     JUMP_INIT (doallocate, _IO_wfile_doallocate),
 249     JUMP_INIT (read, _IO_file_read),
 250     JUMP_INIT (write, _IO_new_file_write),
 251     JUMP_INIT (seek, _IO_file_seek),
 252     JUMP_INIT (close, _IO_file_close_mmap),
 253     JUMP_INIT (stat, _IO_file_stat),
 254     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 255     JUMP_INIT (imbue, _IO_default_imbue)
 256   },
 257   /* _IO_wfile_jumps_maybe_mmap  */
 258   [IO_WFILE_JUMPS_MAYBE_MMAP] = {
 259     JUMP_INIT_DUMMY,
 260     JUMP_INIT (finish, _IO_new_file_finish),
 261     JUMP_INIT (overflow, (_IO_overflow_t) _IO_wfile_overflow),
 262     JUMP_INIT (underflow, (_IO_underflow_t) _IO_wfile_underflow_maybe_mmap),
 263     JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
 264     JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wdefault_pbackfail),
 265     JUMP_INIT (xsputn, _IO_wfile_xsputn),
 266     JUMP_INIT (xsgetn, _IO_file_xsgetn),
 267     JUMP_INIT (seekoff, _IO_wfile_seekoff),
 268     JUMP_INIT (seekpos, _IO_default_seekpos),
 269     JUMP_INIT (setbuf, _IO_file_setbuf_mmap),
 270     JUMP_INIT (sync, (_IO_sync_t) _IO_wfile_sync),
 271     JUMP_INIT (doallocate, _IO_wfile_doallocate),
 272     JUMP_INIT (read, _IO_file_read),
 273     JUMP_INIT (write, _IO_new_file_write),
 274     JUMP_INIT (seek, _IO_file_seek),
 275     JUMP_INIT (close, _IO_file_close),
 276     JUMP_INIT (stat, _IO_file_stat),
 277     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 278     JUMP_INIT (imbue, _IO_default_imbue)
 279   },
 280   /* _IO_cookie_jumps  */
 281   [IO_COOKIE_JUMPS] = {
 282     JUMP_INIT_DUMMY,
 283     JUMP_INIT (finish, _IO_file_finish),
 284     JUMP_INIT (overflow, _IO_file_overflow),
 285     JUMP_INIT (underflow, _IO_file_underflow),
 286     JUMP_INIT (uflow, _IO_default_uflow),
 287     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 288     JUMP_INIT (xsputn, _IO_file_xsputn),
 289     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 290     JUMP_INIT (seekoff, _IO_cookie_seekoff),
 291     JUMP_INIT (seekpos, _IO_default_seekpos),
 292     JUMP_INIT (setbuf, _IO_file_setbuf),
 293     JUMP_INIT (sync, _IO_file_sync),
 294     JUMP_INIT (doallocate, _IO_file_doallocate),
 295     JUMP_INIT (read, _IO_cookie_read),
 296     JUMP_INIT (write, _IO_cookie_write),
 297     JUMP_INIT (seek, _IO_cookie_seek),
 298     JUMP_INIT (close, _IO_cookie_close),
 299     JUMP_INIT (stat, _IO_default_stat),
 300     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 301     JUMP_INIT (imbue, _IO_default_imbue),
 302   },
 303   /* _IO_proc_jumps  */
 304   [IO_PROC_JUMPS] = {
 305     JUMP_INIT_DUMMY,
 306     JUMP_INIT (finish, _IO_new_file_finish),
 307     JUMP_INIT (overflow, _IO_new_file_overflow),
 308     JUMP_INIT (underflow, _IO_new_file_underflow),
 309     JUMP_INIT (uflow, _IO_default_uflow),
 310     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 311     JUMP_INIT (xsputn, _IO_new_file_xsputn),
 312     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 313     JUMP_INIT (seekoff, _IO_new_file_seekoff),
 314     JUMP_INIT (seekpos, _IO_default_seekpos),
 315     JUMP_INIT (setbuf, _IO_new_file_setbuf),
 316     JUMP_INIT (sync, _IO_new_file_sync),
 317     JUMP_INIT (doallocate, _IO_file_doallocate),
 318     JUMP_INIT (read, _IO_file_read),
 319     JUMP_INIT (write, _IO_new_file_write),
 320     JUMP_INIT (seek, _IO_file_seek),
 321     JUMP_INIT (close, _IO_new_proc_close),
 322     JUMP_INIT (stat, _IO_file_stat),
 323     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 324     JUMP_INIT (imbue, _IO_default_imbue)
 325   },
 326   /* _IO_mem_jumps  */
 327   [IO_MEM_JUMPS] = {
 328     JUMP_INIT_DUMMY,
 329     JUMP_INIT (finish, _IO_mem_finish),
 330     JUMP_INIT (overflow, _IO_str_overflow),
 331     JUMP_INIT (underflow, _IO_str_underflow),
 332     JUMP_INIT (uflow, _IO_default_uflow),
 333     JUMP_INIT (pbackfail, _IO_str_pbackfail),
 334     JUMP_INIT (xsputn, _IO_default_xsputn),
 335     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 336     JUMP_INIT (seekoff, _IO_str_seekoff),
 337     JUMP_INIT (seekpos, _IO_default_seekpos),
 338     JUMP_INIT (setbuf, _IO_default_setbuf),
 339     JUMP_INIT (sync, _IO_mem_sync),
 340     JUMP_INIT (doallocate, _IO_default_doallocate),
 341     JUMP_INIT (read, _IO_default_read),
 342     JUMP_INIT (write, _IO_default_write),
 343     JUMP_INIT (seek, _IO_default_seek),
 344     JUMP_INIT (close, _IO_default_close),
 345     JUMP_INIT (stat, _IO_default_stat),
 346     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 347     JUMP_INIT (imbue, _IO_default_imbue)
 348   },
 349   /* _IO_wmem_jumps  */
 350   [IO_WMEM_JUMPS] = {
 351     JUMP_INIT_DUMMY,
 352     JUMP_INIT (finish, _IO_wmem_finish),
 353     JUMP_INIT (overflow, (_IO_overflow_t) _IO_wstr_overflow),
 354     JUMP_INIT (underflow, (_IO_underflow_t) _IO_wstr_underflow),
 355     JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
 356     JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wstr_pbackfail),
 357     JUMP_INIT (xsputn, _IO_wdefault_xsputn),
 358     JUMP_INIT (xsgetn, _IO_wdefault_xsgetn),
 359     JUMP_INIT (seekoff, _IO_wstr_seekoff),
 360     JUMP_INIT (seekpos, _IO_default_seekpos),
 361     JUMP_INIT (setbuf, _IO_default_setbuf),
 362     JUMP_INIT (sync, _IO_wmem_sync),
 363     JUMP_INIT (doallocate, _IO_wdefault_doallocate),
 364     JUMP_INIT (read, _IO_default_read),
 365     JUMP_INIT (write, _IO_default_write),
 366     JUMP_INIT (seek, _IO_default_seek),
 367     JUMP_INIT (close, _IO_default_close),
 368     JUMP_INIT (stat, _IO_default_stat),
 369     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 370     JUMP_INIT (imbue, _IO_default_imbue)
 371   },
 372   [IO_PRINTF_BUFFER_AS_FILE_JUMPS] = {
 373     JUMP_INIT_DUMMY,
 374     JUMP_INIT (finish, NULL),
 375     JUMP_INIT (overflow, __printf_buffer_as_file_overflow),
 376     JUMP_INIT (underflow, NULL),
 377     JUMP_INIT (uflow, NULL),
 378     JUMP_INIT (pbackfail, NULL),
 379     JUMP_INIT (xsputn, __printf_buffer_as_file_xsputn),
 380     JUMP_INIT (xsgetn, NULL),
 381     JUMP_INIT (seekoff, NULL),
 382     JUMP_INIT (seekpos, NULL),
 383     JUMP_INIT (setbuf, NULL),
 384     JUMP_INIT (sync, NULL),
 385     JUMP_INIT (doallocate, NULL),
 386     JUMP_INIT (read, NULL),
 387     JUMP_INIT (write, NULL),
 388     JUMP_INIT (seek, NULL),
 389     JUMP_INIT (close, NULL),
 390     JUMP_INIT (stat, NULL),
 391     JUMP_INIT (showmanyc, NULL),
 392     JUMP_INIT (imbue, NULL)
 393   },
 394   [IO_WPRINTF_BUFFER_AS_FILE_JUMPS] = {
 395     JUMP_INIT_DUMMY,
 396     JUMP_INIT (finish, NULL),
 397     JUMP_INIT (overflow, (_IO_overflow_t) __wprintf_buffer_as_file_overflow),
 398     JUMP_INIT (underflow, NULL),
 399     JUMP_INIT (uflow, NULL),
 400     JUMP_INIT (pbackfail, NULL),
 401     JUMP_INIT (xsputn, __wprintf_buffer_as_file_xsputn),
 402     JUMP_INIT (xsgetn, NULL),
 403     JUMP_INIT (seekoff, NULL),
 404     JUMP_INIT (seekpos, NULL),
 405     JUMP_INIT (setbuf, NULL),
 406     JUMP_INIT (sync, NULL),
 407     JUMP_INIT (doallocate, NULL),
 408     JUMP_INIT (read, NULL),
 409     JUMP_INIT (write, NULL),
 410     JUMP_INIT (seek, NULL),
 411     JUMP_INIT (close, NULL),
 412     JUMP_INIT (stat, NULL),
 413     JUMP_INIT (showmanyc, NULL),
 414     JUMP_INIT (imbue, NULL)
 415   },
 416
 417 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
 418   /* _IO_old_file_jumps  */
 419   [IO_OLD_FILE_JUMPS] = {
 420     JUMP_INIT_DUMMY,
 421     JUMP_INIT (finish, _IO_old_file_finish),
 422     JUMP_INIT (overflow, _IO_old_file_overflow),
 423     JUMP_INIT (underflow, _IO_old_file_underflow),
 424     JUMP_INIT (uflow, _IO_default_uflow),
 425     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 426     JUMP_INIT (xsputn, _IO_old_file_xsputn),
 427     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 428     JUMP_INIT (seekoff, _IO_old_file_seekoff),
 429     JUMP_INIT (seekpos, _IO_default_seekpos),
 430     JUMP_INIT (setbuf, _IO_old_file_setbuf),
 431     JUMP_INIT (sync, _IO_old_file_sync),
 432     JUMP_INIT (doallocate, _IO_file_doallocate),
 433     JUMP_INIT (read, _IO_file_read),
 434     JUMP_INIT (write, _IO_old_file_write),
 435     JUMP_INIT (seek, _IO_file_seek),
 436     JUMP_INIT (close, _IO_file_close),
 437     JUMP_INIT (stat, _IO_file_stat)
 438   },
 439   /*  _IO_old_proc_jumps  */
 440   [IO_OLD_PROC_JUMPS] = {
 441     JUMP_INIT_DUMMY,
 442     JUMP_INIT (finish, _IO_old_file_finish),
 443     JUMP_INIT (overflow, _IO_old_file_overflow),
 444     JUMP_INIT (underflow, _IO_old_file_underflow),
 445     JUMP_INIT (uflow, _IO_default_uflow),
 446     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 447     JUMP_INIT (xsputn, _IO_old_file_xsputn),
 448     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 449     JUMP_INIT (seekoff, _IO_old_file_seekoff),
 450     JUMP_INIT (seekpos, _IO_default_seekpos),
 451     JUMP_INIT (setbuf, _IO_old_file_setbuf),
 452     JUMP_INIT (sync, _IO_old_file_sync),
 453     JUMP_INIT (doallocate, _IO_file_doallocate),
 454     JUMP_INIT (read, _IO_file_read),
 455     JUMP_INIT (write, _IO_old_file_write),
 456     JUMP_INIT (seek, _IO_file_seek),
 457     JUMP_INIT (close, _IO_old_proc_close),
 458     JUMP_INIT (stat, _IO_file_stat),
 459     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 460     JUMP_INIT (imbue, _IO_default_imbue)
 461   },
 462 #endif
 463
 464 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)
 465   /* _IO_old_cookie_jumps  */
 466   [IO_OLD_COOKIED_JUMPS] = {
 467     JUMP_INIT_DUMMY,
 468     JUMP_INIT (finish, _IO_file_finish),
 469     JUMP_INIT (overflow, _IO_file_overflow),
 470     JUMP_INIT (underflow, _IO_file_underflow),
 471     JUMP_INIT (uflow, _IO_default_uflow),
 472     JUMP_INIT (pbackfail, _IO_default_pbackfail),
 473     JUMP_INIT (xsputn, _IO_file_xsputn),
 474     JUMP_INIT (xsgetn, _IO_default_xsgetn),
 475     JUMP_INIT (seekoff, _IO_cookie_seekoff),
 476     JUMP_INIT (seekpos, _IO_default_seekpos),
 477     JUMP_INIT (setbuf, _IO_file_setbuf),
 478     JUMP_INIT (sync, _IO_file_sync),
 479     JUMP_INIT (doallocate, _IO_file_doallocate),
 480     JUMP_INIT (read, _IO_cookie_read),
 481     JUMP_INIT (write, _IO_cookie_write),
 482     JUMP_INIT (seek, _IO_old_cookie_seek),
 483     JUMP_INIT (close, _IO_cookie_close),
 484     JUMP_INIT (stat, _IO_default_stat),
 485     JUMP_INIT (showmanyc, _IO_default_showmanyc),
 486     JUMP_INIT (imbue, _IO_default_imbue),
 487   },
 488 #endif
 489 };
 490
 491 #ifdef SHARED
 492
 493 void (*IO_accept_foreign_vtables) (void) attribute_hidden;
 494
 495 #else  /* !SHARED */
 496
 497 /* Used to check whether static dlopen support is needed.  */
 498 # pragma weak __dlopen
 499
 500 #endif
 501
 502 void attribute_hidden
 503 _IO_vtable_check (void)
 504 {
 505 #ifdef SHARED
 506   /* Honor the compatibility flag.  */
 507   void (*flag) (void) = atomic_load_relaxed (&IO_accept_foreign_vtables);
 508   PTR_DEMANGLE (flag);
 509   if (flag == &_IO_vtable_check)
 510     return;
 511
 512   /* In case this libc copy is in a non-default namespace, we always
 513      need to accept foreign vtables because there is always a
 514      possibility that FILE * objects are passed across the linking
 515      boundary.  */
 516   {
 517     Dl_info di;
 518     struct link_map *l;
 519     if (!rtld_active ()
 520         || (_dl_addr (_IO_vtable_check, &di, &l, NULL) != 0
 521             && l->l_ns != LM_ID_BASE))
 522       return;
 523   }
 524
 525 #else /* !SHARED */
 526   /* We cannot perform vtable validation in the static dlopen case
 527      because FILE * handles might be passed back and forth across the
 528      boundary.  Therefore, we disable checking in this case.  */
 529   if (__dlopen != NULL)
 530     return;
 531 #endif
 532
 533   __libc_fatal ("Fatal error: glibc detected an invalid stdio handle\n");
 534 }
 535
 536 /* Some variants of libstdc++ interpose _IO_2_1_stdin_ etc. and
 537    install their own vtables directly, without calling _IO_init or
 538    other functions.  Detect this by looking at the vtables values
 539    during startup, and disable vtable validation in this case.  */
 540 #ifdef SHARED
 541 __attribute__ ((constructor))
 542 static void
 543 check_stdfiles_vtables (void)
 544 {
 545   if (_IO_2_1_stdin_.vtable != &_IO_file_jumps
 546       || _IO_2_1_stdout_.vtable != &_IO_file_jumps
 547       || _IO_2_1_stderr_.vtable != &_IO_file_jumps)
 548     IO_set_accept_foreign_vtables (&_IO_vtable_check);
 549 }
 550 #endif
 551
 552 #define STR(s)  XSTR(s)
 553 #define XSTR(s) #s
 554
 555 #undef _IO_file_jumps
 556 #define _IO_file_jumps_alias  "__io_vtables + " STR(IO_FILE_JUMPS_OFFSET)
 557 declare_object_symbol_alias (_IO_file_jumps, _IO_file_jumps_alias,
 558                              IO_JUMP_T_SIZE)
 559 #undef _IO_wfile_jumps
 560 #define _IO_wfile_jumps_alias  "__io_vtables + " STR(IO_WFILE_JUMPS_OFFSET)
 561 declare_object_symbol_alias (_IO_wfile_jumps, _IO_wfile_jumps_alias,
 562                              IO_JUMP_T_SIZE)