diff options
Diffstat (limited to 'sysdeps/nacl/dl-map-segments.h')
| -rw-r--r-- | sysdeps/nacl/dl-map-segments.h | 269 |
1 files changed, 0 insertions, 269 deletions
diff --git a/sysdeps/nacl/dl-map-segments.h b/sysdeps/nacl/dl-map-segments.h deleted file mode 100644 index ab2ad43838..0000000000 --- a/sysdeps/nacl/dl-map-segments.h +++ /dev/null @@ -1,269 +0,0 @@ -/* Map in a shared object's segments. NaCl version. - Copyright (C) 2015-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _NACL_DL_MAP_SEGMENTS_H -#define _NACL_DL_MAP_SEGMENTS_H 1 - -#include <assert.h> -#include <dl-load.h> -#include <errno.h> -#include <stdbool.h> -#include <unistd.h> -#include <libc-pointer-arith.h> - - -/* This is basically pread, but with iteration after short reads. */ -static bool -read_in_data (int fd, void *data, size_t len, off_t pos) -{ - if (__glibc_unlikely (__lseek (fd, pos, SEEK_SET) == (off_t) -1)) - return true; - while (len > 0) - { - ssize_t n = __read (fd, data, len); - if (__glibc_unlikely (n < 0)) - return true; - if (__glibc_unlikely (n == 0)) - { - errno = EFTYPE; - return true; - } - data += n; - len -= n; - } - return false; -} - -static const char * -_dl_map_segments (struct link_map *l, int fd, - const ElfW(Ehdr) *header, int type, - const struct loadcmd loadcmds[], size_t nloadcmds, - const size_t maplength, bool has_holes, - struct link_map *loader) -{ - if (__glibc_likely (type == ET_DYN)) - { - /* This is a position-independent shared object. Let the system - choose where to place it. - - As a refinement, sometimes we have an address that we would - prefer to map such objects at; but this is only a preference, - the OS can do whatever it likes. */ - ElfW(Addr) mappref - = (ELF_PREFERRED_ADDRESS (loader, maplength, - loadcmds[0].mapstart & GLRO(dl_use_load_bias)) - - MAP_BASE_ADDR (l)); - - uintptr_t mapstart; - if (__glibc_likely (loadcmds[0].prot & PROT_EXEC)) - { - /* When there is a code segment, we must use the - allocate_code_data interface to choose a location. */ - - uintptr_t code_size = loadcmds[0].allocend - loadcmds[0].mapstart; - uintptr_t data_offset; - size_t data_size; - - if (__glibc_likely (nloadcmds > 1)) - { - data_offset = loadcmds[1].mapstart - loadcmds[0].mapstart; - data_size = ALIGN_UP (maplength - data_offset, - GLRO(dl_pagesize)); - } - else - { - data_offset = 0; - data_size = 0; - } - - int error = __nacl_irt_code_data_alloc.allocate_code_data - (mappref, code_size, data_offset, data_size, &mapstart); - if (__glibc_unlikely (error)) - { - errno = error; - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - } - } - else - { - /* With no code pages involved, plain mmap works fine. */ - void *mapped = __mmap ((void *) mappref, maplength, - PROT_NONE, MAP_ANON, -1, 0); - if (__glibc_unlikely (mapped == MAP_FAILED)) - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - mapstart = (uintptr_t) mapped; - } - - l->l_addr = mapstart - loadcmds[0].mapstart; - } - - /* Remember which part of the address space this object uses. */ - l->l_map_start = loadcmds[0].mapstart + l->l_addr; - l->l_map_end = l->l_map_start + maplength; - l->l_contiguous = !has_holes; - - /* Now actually map (or read) in each segment. */ - for (const struct loadcmd *c = loadcmds; c < &loadcmds[nloadcmds]; ++c) - if (__glibc_likely (c->mapend > c->mapstart)) - { - /* Unlike POSIX mmap, NaCl's mmap does not reliably handle COW - faults in the remainder of the final partial page. So to get - the expected behavior for the unaligned boundary between data - and bss, it's necessary to allocate the final partial page of - data as anonymous memory rather than mapping it from the file. */ - - size_t maplen = c->mapend - c->mapstart; - if (c->mapend > c->dataend && c->allocend > c->dataend) - maplen = (c->dataend & -GLRO(dl_pagesize)) - c->mapstart; - - /* Map the segment contents from the file. */ - if (__glibc_unlikely (__mmap ((void *) (l->l_addr + c->mapstart), - maplen, c->prot, - MAP_FIXED|MAP_COPY|MAP_FILE, - fd, c->mapoff) - == MAP_FAILED)) - { - switch (errno) - { - case EINVAL: - case ENOTSUP: - case ENOSYS: - break; - default: - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - } - - /* No mmap support for this file. */ - if (c->prot & PROT_EXEC) - { - /* Read the data into a temporary buffer. */ - const size_t len = c->mapend - c->mapstart; - void *data = __mmap (NULL, len, PROT_READ | PROT_WRITE, - MAP_ANON|MAP_PRIVATE, -1, 0); - if (__glibc_unlikely (data == MAP_FAILED)) - return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL; - if (read_in_data (fd, data, len, c->mapoff)) - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - /* Now validate and install the code. */ - int error = __nacl_irt_dyncode.dyncode_create - ((void *) (l->l_addr + c->mapstart), data, len); - __munmap (data, len); - if (__glibc_unlikely (error)) - { - errno = error; - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - } - if (__glibc_unlikely (type != ET_DYN)) - { - /* A successful PROT_EXEC mmap would have implicitly - updated the bookkeeping so that a future - allocate_code_data call would know that this range - of the address space is already occupied. That - doesn't happen implicitly with dyncode_create, so - it's necessary to do an explicit call to update the - bookkeeping. */ - uintptr_t allocated_address; - error = __nacl_irt_code_data_alloc.allocate_code_data - (l->l_addr + c->mapstart, len, 0, 0, &allocated_address); - if (__glibc_unlikely (error)) - { - errno = error; - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - } - if (__glibc_unlikely - (allocated_address != l->l_addr + c->mapstart)) - { - /* This is not a very helpful error for this case, - but there isn't really anything better to use. */ - errno = ENOMEM; - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - } - } - } - else - { - /* Allocate the pages. */ - if (__mmap ((void *) (l->l_addr + c->mapstart), - c->mapend - c->mapstart, c->prot | PROT_WRITE, - MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0) - == MAP_FAILED) - return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL; - /* Now read in the data. */ - if (read_in_data (fd, (void *) (l->l_addr + c->mapstart), - c->dataend - c->mapstart, c->mapoff)) - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - /* Now that we've filled the pages, reset the page - protections to what they should be. */ - if (!(c->prot & PROT_WRITE) - && __mprotect ((void *) (l->l_addr + c->mapstart), - c->mapend - c->mapstart, c->prot) < 0) - return DL_MAP_SEGMENTS_ERROR_MPROTECT; - } - } - else if (c->allocend > c->dataend) - { - /* Extra zero pages should appear at the end of this segment, - after the data mapped from the file. */ - - uintptr_t allocend = c->mapend; - if (c->mapend > c->dataend) - { - /* The final data page was partial. So we didn't map it in. - Instead, we must allocate an anonymous page to fill. */ - if (c->prot & PROT_WRITE) - /* Do the whole allocation right here. */ - allocend = c->allocend; - if (__mmap ((void *) (l->l_addr + c->mapstart + maplen), - allocend - (c->mapstart + maplen), c->prot, - MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0) - == MAP_FAILED) - return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL; - if (read_in_data (fd, - (void *) (l->l_addr + c->mapstart + maplen), - c->dataend & (GLRO(dl_pagesize) - 1), - c->mapoff + maplen)) - return DL_MAP_SEGMENTS_ERROR_MAP_SEGMENT; - /* Now that we've filled the page, reset its - protections to what they should be. */ - if (!(c->prot & PROT_WRITE) - && __mprotect ((void *) (l->l_addr + c->mapstart + maplen), - c->mapend - (c->mapstart + maplen), - c->prot) < 0) - return DL_MAP_SEGMENTS_ERROR_MPROTECT; - } - - /* Now allocate the pure zero-fill pages. */ - if (allocend < c->allocend - && (__mmap ((void *) (l->l_addr + c->mapstart + allocend), - c->allocend - (c->mapstart + allocend), c->prot, - MAP_FIXED|MAP_ANON|MAP_PRIVATE, -1, 0) - == MAP_FAILED)) - return DL_MAP_SEGMENTS_ERROR_MAP_ZERO_FILL; - } - - _dl_postprocess_loadcmd (l, header, c); - } - - /* Notify ELF_PREFERRED_ADDRESS that we have to load this one - fixed. */ - ELF_FIXED_ADDRESS (loader, c->mapstart); - - return NULL; -} - -#endif /* dl-map-segments.h */ |