/* $NetBSD: elf_update.c,v 1.5 2013/10/18 08:04:47 mrg Exp $ */ /*- * Copyright (c) 2006-2008 Joseph Koshy * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if HAVE_NBTOOL_CONFIG_H # include "nbtool_config.h" #endif #include /* __FBSDID("$FreeBSD: src/lib/libelf/elf_update.c,v 1.5.2.1.2.1 2009/10/25 01:10:29 kensmith Exp $"); */ #include #include #include #include #include #include #include #include #include #include "_libelf.h" /* * Update the internal data structures associated with an ELF object. * Returns the size in bytes the ELF object would occupy in its file * representation. * * After a successful call to this function, the following structures * are updated: * * - The ELF header is updated. * - All sections are sorted in order of ascending addresses and their * section header table entries updated. An error is signalled * if an overlap was detected among sections. * - All data descriptors associated with a section are sorted in order * of ascending addresses. Overlaps, if detected, are signalled as * errors. Other sanity checks for alignments, section types etc. are * made. * * After a resync_elf() successfully returns, the ELF descriptor is * ready for being handed over to _libelf_write_elf(). * * File alignments: * PHDR - Addr * SHDR - Addr * * XXX: how do we handle 'flags'. */ /* * Compute the extents of a section, by looking at the data * descriptors associated with it. The function returns zero if an * error was detected. `*rc' holds the maximum file extent seen so * far. */ static int _libelf_compute_section_extents(Elf *e, Elf_Scn *s, off_t *rc) { int ec; Elf_Data *d, *td; unsigned int elftype; uint32_t sh_type; uint64_t d_align; uint64_t sh_align, sh_entsize, sh_offset, sh_size; uint64_t scn_size, scn_alignment; /* * We need to recompute library private data structures if one * or more of the following is true: * - The underlying Shdr structure has been marked `dirty'. Significant * fields include: `sh_offset', `sh_type', `sh_size', `sh_addralign'. * - The Elf_Data structures part of this section have been marked * `dirty'. Affected members include `d_align', `d_offset', `d_type', * and `d_size'. * - The section as a whole is `dirty', e.g., it has been allocated * using elf_newscn(), or if a new Elf_Data structure was added using * elf_newdata(). * * Each of these conditions would result in the ELF_F_DIRTY bit being * set on the section descriptor's `s_flags' field. */ ec = e->e_class; if (ec == ELFCLASS32) { sh_type = s->s_shdr.s_shdr32.sh_type; sh_align = (uint64_t) s->s_shdr.s_shdr32.sh_addralign; sh_entsize = (uint64_t) s->s_shdr.s_shdr32.sh_entsize; sh_offset = (uint64_t) s->s_shdr.s_shdr32.sh_offset; sh_size = (uint64_t) s->s_shdr.s_shdr32.sh_size; } else { sh_type = s->s_shdr.s_shdr64.sh_type; sh_align = s->s_shdr.s_shdr64.sh_addralign; sh_entsize = s->s_shdr.s_shdr64.sh_entsize; sh_offset = s->s_shdr.s_shdr64.sh_offset; sh_size = s->s_shdr.s_shdr64.sh_size; } if (sh_type == SHT_NULL || sh_type == SHT_NOBITS) return (1); if ((s->s_flags & ELF_F_DIRTY) == 0) { if ((size_t) *rc < sh_offset + sh_size) *rc = sh_offset + sh_size; return (1); } elftype = _libelf_xlate_shtype(sh_type); if (elftype > ELF_T_LAST) { LIBELF_SET_ERROR(SECTION, 0); return (0); } /* * Compute the extent of the data descriptors associated with * this section. */ scn_alignment = 0; if (sh_align == 0) sh_align = _libelf_falign(elftype, ec); /* Compute the section alignment. */ STAILQ_FOREACH(d, &s->s_data, d_next) { if (d->d_type != elftype) { LIBELF_SET_ERROR(DATA, 0); return (0); } if (d->d_version != e->e_version) { LIBELF_SET_ERROR(VERSION, 0); return (0); } if ((d_align = d->d_align) % sh_align) { LIBELF_SET_ERROR(LAYOUT, 0); return (0); } if (d_align == 0 || (d_align & (d_align - 1))) { LIBELF_SET_ERROR(DATA, 0); return (0); } if (d_align > scn_alignment) scn_alignment = d_align; } scn_size = 0L; STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) { if (e->e_flags & ELF_F_LAYOUT) { if ((uint64_t) d->d_off + d->d_size > scn_size) scn_size = d->d_off + d->d_size; } else { scn_size = roundup2(scn_size, scn_alignment); d->d_off = scn_size; scn_size += d->d_size; } } /* * If the application is requesting full control over the layout * of the section, check its values for sanity. */ if (e->e_flags & ELF_F_LAYOUT) { if (scn_alignment > sh_align || sh_offset % sh_align || sh_size < scn_size) { LIBELF_SET_ERROR(LAYOUT, 0); return (0); } } else { /* * Otherwise compute the values in the section header. */ if (scn_alignment > sh_align) sh_align = scn_alignment; /* * If the section entry size is zero, try and fill in an * appropriate entry size. Per the elf(5) manual page * sections without fixed-size entries should have their * 'sh_entsize' field set to zero. */ if (sh_entsize == 0 && (sh_entsize = _libelf_fsize(elftype, ec, e->e_version, (size_t) 1)) == 1) sh_entsize = 0; sh_size = scn_size; sh_offset = roundup(*rc, sh_align); if (ec == ELFCLASS32) { s->s_shdr.s_shdr32.sh_addralign = (uint32_t) sh_align; s->s_shdr.s_shdr32.sh_entsize = (uint32_t) sh_entsize; s->s_shdr.s_shdr32.sh_offset = (uint32_t) sh_offset; s->s_shdr.s_shdr32.sh_size = (uint32_t) sh_size; } else { s->s_shdr.s_shdr64.sh_addralign = sh_align; s->s_shdr.s_shdr64.sh_entsize = sh_entsize; s->s_shdr.s_shdr64.sh_offset = sh_offset; s->s_shdr.s_shdr64.sh_size = sh_size; } } if ((size_t) *rc < sh_offset + sh_size) *rc = sh_offset + sh_size; s->s_size = sh_size; s->s_offset = sh_offset; return (1); } /* * Insert a section in ascending order in the list */ static int _libelf_insert_section(Elf *e, Elf_Scn *s) { Elf_Scn *t, *prevt; uint64_t smax, smin, tmax, tmin; smin = s->s_offset; smax = smin + s->s_size; prevt = NULL; STAILQ_FOREACH(t, &e->e_u.e_elf.e_scn, s_next) { tmin = t->s_offset; tmax = tmin + t->s_size; if (tmax <= smin) { /* * 't' lies entirely before 's': ...| t |...| s |... */ prevt = t; continue; } else if (smax <= tmin) /* * 's' lies entirely before 't', and after 'prevt': * ...| prevt |...| s |...| t |... */ break; else { /* 's' and 't' overlap. */ LIBELF_SET_ERROR(LAYOUT, 0); return (0); } } if (prevt) STAILQ_INSERT_AFTER(&e->e_u.e_elf.e_scn, prevt, s, s_next); else STAILQ_INSERT_HEAD(&e->e_u.e_elf.e_scn, s, s_next); return (1); } static off_t _libelf_resync_sections(Elf *e, off_t rc) { int ec; off_t nrc; size_t sh_type, shdr_start, shdr_end; Elf_Scn *s, *ts; ec = e->e_class; /* * Make a pass through sections, computing the extent of each * section. Order in increasing order of addresses. */ nrc = rc; STAILQ_FOREACH(s, &e->e_u.e_elf.e_scn, s_next) if (_libelf_compute_section_extents(e, s, &nrc) == 0) return ((off_t) -1); STAILQ_FOREACH_SAFE(s, &e->e_u.e_elf.e_scn, s_next, ts) { if (ec == ELFCLASS32) sh_type = s->s_shdr.s_shdr32.sh_type; else sh_type = s->s_shdr.s_shdr64.sh_type; /* XXX Do we need the 'size' field of an SHT_NOBITS section */ if (sh_type == SHT_NOBITS || sh_type == SHT_NULL) continue; if (s->s_offset < (uint64_t) rc) { if (s->s_offset + s->s_size < (uint64_t) rc) { /* * Try insert this section in the * correct place in the list, * detecting overlaps if any. */ STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next); if (_libelf_insert_section(e, s) == 0) return ((off_t) -1); } else { LIBELF_SET_ERROR(LAYOUT, 0); return ((off_t) -1); } } else rc = s->s_offset + s->s_size; } /* * If the application is controlling file layout, check for an * overlap between this section's extents and the SHDR table. */ if (e->e_flags & ELF_F_LAYOUT) { if (e->e_class == ELFCLASS32) shdr_start = e->e_u.e_elf.e_ehdr.e_ehdr32->e_shoff; else shdr_start = e->e_u.e_elf.e_ehdr.e_ehdr64->e_shoff; shdr_end = shdr_start + _libelf_fsize(ELF_T_SHDR, e->e_class, e->e_version, e->e_u.e_elf.e_nscn); STAILQ_FOREACH(s, &e->e_u.e_elf.e_scn, s_next) { if (s->s_offset >= shdr_end || s->s_offset + s->s_size <= shdr_start) continue; LIBELF_SET_ERROR(LAYOUT, 0); return ((off_t) -1); } } assert(nrc == rc); return (rc); } static off_t _libelf_resync_elf(Elf *e) { int ec, eh_class; unsigned int eh_byteorder, eh_version; size_t align, fsz; size_t phnum, shnum; off_t rc, phoff, shoff; void *ehdr; Elf32_Ehdr *eh32; Elf64_Ehdr *eh64; rc = 0; ec = e->e_class; assert(ec == ELFCLASS32 || ec == ELFCLASS64); /* * Prepare the EHDR. */ if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) return ((off_t) -1); eh32 = ehdr; eh64 = ehdr; if (ec == ELFCLASS32) { eh_byteorder = eh32->e_ident[EI_DATA]; eh_class = eh32->e_ident[EI_CLASS]; phoff = (uint64_t) eh32->e_phoff; shoff = (uint64_t) eh32->e_shoff; eh_version = eh32->e_version; } else { eh_byteorder = eh64->e_ident[EI_DATA]; eh_class = eh64->e_ident[EI_CLASS]; phoff = eh64->e_phoff; shoff = eh64->e_shoff; eh_version = eh64->e_version; } if (eh_version == EV_NONE) eh_version = EV_CURRENT; if (eh_version != e->e_version) { /* always EV_CURRENT */ LIBELF_SET_ERROR(VERSION, 0); return ((off_t) -1); } if (eh_class != e->e_class) { LIBELF_SET_ERROR(CLASS, 0); return ((off_t) -1); } if (e->e_cmd != ELF_C_WRITE && eh_byteorder != e->e_byteorder) { LIBELF_SET_ERROR(HEADER, 0); return ((off_t) -1); } shnum = e->e_u.e_elf.e_nscn; phnum = e->e_u.e_elf.e_nphdr; e->e_byteorder = eh_byteorder; #define INITIALIZE_EHDR(E,EC,V) do { \ (E)->e_ident[EI_MAG0] = ELFMAG0; \ (E)->e_ident[EI_MAG1] = ELFMAG1; \ (E)->e_ident[EI_MAG2] = ELFMAG2; \ (E)->e_ident[EI_MAG3] = ELFMAG3; \ (E)->e_ident[EI_CLASS] = (EC); \ (E)->e_ident[EI_VERSION] = (V); \ (E)->e_ehsize = _libelf_fsize(ELF_T_EHDR, (EC), (V), \ (size_t) 1); \ (E)->e_phentsize = _libelf_fsize(ELF_T_PHDR, (EC), (V), \ (size_t) 1); \ (E)->e_shentsize = _libelf_fsize(ELF_T_SHDR, (EC), (V), \ (size_t) 1); \ } while (/*CONSTCOND*/0) if (ec == ELFCLASS32) INITIALIZE_EHDR(eh32, ec, eh_version); else INITIALIZE_EHDR(eh64, ec, eh_version); (void) elf_flagehdr(e, ELF_C_SET, ELF_F_DIRTY); rc += _libelf_fsize(ELF_T_EHDR, ec, eh_version, (size_t) 1); /* * Compute the layout the program header table, if one is * present. The program header table needs to be aligned to a * `natural' boundary. */ if (phnum) { fsz = _libelf_fsize(ELF_T_PHDR, ec, eh_version, phnum); align = _libelf_falign(ELF_T_PHDR, ec); if (e->e_flags & ELF_F_LAYOUT) { /* * Check offsets for sanity. */ if (rc > phoff) { LIBELF_SET_ERROR(HEADER, 0); return ((off_t) -1); } if (phoff % align) { LIBELF_SET_ERROR(LAYOUT, 0); return ((off_t) -1); } } else phoff = roundup(rc, align); rc = phoff + fsz; } else phoff = 0; /* * Compute the layout of the sections associated with the * file. */ if ((rc = _libelf_resync_sections(e, rc)) < 0) return ((off_t) -1); /* * Compute the space taken up by the section header table, if * one is needed. If ELF_F_LAYOUT is asserted, the * application may have placed the section header table in * between existing sections, so the net size of the file need * not increase due to the presence of the section header * table. */ if (shnum) { fsz = _libelf_fsize(ELF_T_SHDR, ec, eh_version, (size_t) 1); align = _libelf_falign(ELF_T_SHDR, ec); if (e->e_flags & ELF_F_LAYOUT) { if (shoff % align) { LIBELF_SET_ERROR(LAYOUT, 0); return ((off_t) -1); } } else shoff = roundup(rc, align); if (shoff + fsz * shnum > (size_t) rc) rc = shoff + fsz * shnum; } else shoff = 0; /* * Set the fields of the Executable Header that could potentially use * extended numbering. */ _libelf_setphnum(e, ehdr, ec, phnum); _libelf_setshnum(e, ehdr, ec, shnum); /* * Update the `e_phoff' and `e_shoff' fields if the library is * doing the layout. */ if ((e->e_flags & ELF_F_LAYOUT) == 0) { if (ec == ELFCLASS32) { eh32->e_phoff = (uint32_t) phoff; eh32->e_shoff = (uint32_t) shoff; } else { eh64->e_phoff = (uint64_t) phoff; eh64->e_shoff = (uint64_t) shoff; } } return (rc); } /* * Write out the contents of a section. */ static off_t _libelf_write_scn(Elf *e, char *nf, Elf_Scn *s, off_t rc) { int ec; size_t fsz, msz, nobjects; uint32_t sh_type; uint64_t sh_off; int elftype; Elf_Data *d, dst; if ((ec = e->e_class) == ELFCLASS32) sh_type = s->s_shdr.s_shdr32.sh_type; else sh_type = s->s_shdr.s_shdr64.sh_type; /* * Ignore sections that do not allocate space in the file. */ if (sh_type == SHT_NOBITS || sh_type == SHT_NULL) return (rc); elftype = _libelf_xlate_shtype(sh_type); assert(elftype >= ELF_T_FIRST && elftype <= ELF_T_LAST); msz = _libelf_msize(elftype, ec, e->e_version); sh_off = s->s_offset; assert(sh_off % _libelf_falign(elftype, ec) == 0); /* * If the section has a `rawdata' descriptor, and the section * contents have not been modified, use its contents directly. * The `s_rawoff' member contains the offset into the original * file, while `s_offset' contains its new location in the * destination. */ if (STAILQ_EMPTY(&s->s_data)) { if ((d = elf_rawdata(s, NULL)) == NULL) return ((off_t) -1); STAILQ_FOREACH(d, &s->s_rawdata, d_next) { if ((uint64_t) rc < sh_off + d->d_off) (void) memset(nf + rc, LIBELF_PRIVATE(fillchar), sh_off + d->d_off - rc); rc = sh_off + d->d_off; assert(d->d_buf != NULL); assert(d->d_type == ELF_T_BYTE); assert(d->d_version == e->e_version); (void) memcpy(nf + rc, e->e_rawfile + s->s_rawoff + d->d_off, d->d_size); rc += d->d_size; } return (rc); } /* * Iterate over the set of data descriptors for this section. * The prior call to _libelf_resync_elf() would have setup the * descriptors for this step. */ dst.d_version = e->e_version; STAILQ_FOREACH(d, &s->s_data, d_next) { if ((uint64_t) rc < sh_off + d->d_off) (void) memset(nf + rc, LIBELF_PRIVATE(fillchar), sh_off + d->d_off - rc); rc = sh_off + d->d_off; assert(d->d_buf != NULL); assert(d->d_type == (Elf_Type) elftype); assert(d->d_version == e->e_version); assert(d->d_size % msz == 0); nobjects = d->d_size / msz; fsz = _libelf_fsize(elftype, ec, e->e_version, nobjects); dst.d_buf = nf + rc; dst.d_size = fsz; if (_libelf_xlate(&dst, d, e->e_byteorder, ec, ELF_TOFILE) == NULL) return ((off_t) -1); rc += fsz; } return ((off_t) rc); } /* * Write out the file image. * * The original file could have been mapped in with an ELF_C_RDWR * command and the application could have added new content or * re-arranged its sections before calling elf_update(). Consequently * its not safe to work `in place' on the original file. So we * malloc() the required space for the updated ELF object and build * the object there and write it out to the underlying file at the * end. Note that the application may have opened the underlying file * in ELF_C_RDWR and only retrieved/modified a few sections. We take * care to avoid translating file sections unnecessarily. * * Gaps in the coverage of the file by the file's sections will be * filled with the fill character set by elf_fill(3). */ static off_t _libelf_write_elf(Elf *e, off_t newsize) { int ec; off_t maxrc, rc; size_t fsz, msz, phnum, shnum; uint64_t phoff, shoff; void *ehdr; char *newfile; Elf_Data dst, src; Elf_Scn *scn, *tscn; Elf32_Ehdr *eh32; Elf64_Ehdr *eh64; assert(e->e_kind == ELF_K_ELF); assert(e->e_cmd != ELF_C_READ); assert(e->e_fd >= 0); if ((newfile = malloc((size_t) newsize)) == NULL) { LIBELF_SET_ERROR(RESOURCE, errno); return ((off_t) -1); } ec = e->e_class; ehdr = _libelf_ehdr(e, ec, 0); assert(ehdr != NULL); phnum = e->e_u.e_elf.e_nphdr; if (ec == ELFCLASS32) { eh32 = (Elf32_Ehdr *) ehdr; phoff = (uint64_t) eh32->e_phoff; shnum = eh32->e_shnum; shoff = (uint64_t) eh32->e_shoff; } else { eh64 = (Elf64_Ehdr *) ehdr; phoff = eh64->e_phoff; shnum = eh64->e_shnum; shoff = eh64->e_shoff; } fsz = _libelf_fsize(ELF_T_EHDR, ec, e->e_version, (size_t) 1); msz = _libelf_msize(ELF_T_EHDR, ec, e->e_version); (void) memset(&dst, 0, sizeof(dst)); (void) memset(&src, 0, sizeof(src)); src.d_buf = ehdr; src.d_size = msz; src.d_type = ELF_T_EHDR; src.d_version = dst.d_version = e->e_version; rc = 0; dst.d_buf = newfile + rc; dst.d_size = fsz; if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, ELF_TOFILE) == NULL) goto error; rc += fsz; /* * Write the program header table if present. */ if (phnum != 0 && phoff != 0) { assert((unsigned) rc <= phoff); fsz = _libelf_fsize(ELF_T_PHDR, ec, e->e_version, phnum); assert(phoff % _libelf_falign(ELF_T_PHDR, ec) == 0); assert(fsz > 0); src.d_version = dst.d_version = e->e_version; src.d_type = ELF_T_PHDR; if (ec == ELFCLASS32) src.d_buf = e->e_u.e_elf.e_phdr.e_phdr32; else src.d_buf = e->e_u.e_elf.e_phdr.e_phdr64; src.d_size = phnum * _libelf_msize(ELF_T_PHDR, ec, e->e_version); dst.d_size = fsz; if ((uint64_t) rc < phoff) (void) memset(newfile + rc, LIBELF_PRIVATE(fillchar), phoff - rc); dst.d_buf = newfile + rc; if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, ELF_TOFILE) == NULL) goto error; rc = phoff + fsz; } /* * Write out individual sections. */ STAILQ_FOREACH(scn, &e->e_u.e_elf.e_scn, s_next) if ((rc = _libelf_write_scn(e, newfile, scn, rc)) < 0) goto error; /* * Write out the section header table, if required. Note that * if flag ELF_F_LAYOUT has been set the section header table * could reside in between byte ranges mapped by section * descriptors. */ if (shnum != 0 && shoff != 0) { if ((uint64_t) rc < shoff) (void) memset(newfile + rc, LIBELF_PRIVATE(fillchar), shoff - rc); maxrc = rc; rc = shoff; assert(rc % _libelf_falign(ELF_T_SHDR, ec) == 0); src.d_type = ELF_T_SHDR; src.d_size = _libelf_msize(ELF_T_SHDR, ec, e->e_version); src.d_version = dst.d_version = e->e_version; fsz = _libelf_fsize(ELF_T_SHDR, ec, e->e_version, (size_t) 1); STAILQ_FOREACH(scn, &e->e_u.e_elf.e_scn, s_next) { if (ec == ELFCLASS32) src.d_buf = &scn->s_shdr.s_shdr32; else src.d_buf = &scn->s_shdr.s_shdr64; dst.d_size = fsz; dst.d_buf = newfile + rc + scn->s_ndx * fsz; if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, ELF_TOFILE) != &dst) goto error; } rc += e->e_u.e_elf.e_nscn * fsz; if (maxrc > rc) rc = maxrc; } assert(rc == newsize); /* * Write out the constructed contents and remap the file in * read-only. */ if (e->e_rawfile && munmap(e->e_rawfile, e->e_rawsize) < 0) { LIBELF_SET_ERROR(IO, errno); goto error; } if (write(e->e_fd, newfile, (size_t) newsize) != newsize || lseek(e->e_fd, (off_t) 0, SEEK_SET) < 0) { LIBELF_SET_ERROR(IO, errno); goto error; } if (e->e_cmd != ELF_C_WRITE) { if ((e->e_rawfile = mmap(NULL, (size_t) newsize, PROT_READ, MAP_PRIVATE, e->e_fd, (off_t) 0)) == MAP_FAILED) { LIBELF_SET_ERROR(IO, errno); goto error; } e->e_rawsize = newsize; } /* * Reset flags, remove existing section descriptors and * {E,P}HDR pointers so that a subsequent elf_get{e,p}hdr() * and elf_getscn() will function correctly. */ e->e_flags &= ~ELF_F_DIRTY; STAILQ_FOREACH_SAFE(scn, &e->e_u.e_elf.e_scn, s_next, tscn) _libelf_release_scn(scn); if (ec == ELFCLASS32) { free(e->e_u.e_elf.e_ehdr.e_ehdr32); if (e->e_u.e_elf.e_phdr.e_phdr32) free(e->e_u.e_elf.e_phdr.e_phdr32); e->e_u.e_elf.e_ehdr.e_ehdr32 = NULL; e->e_u.e_elf.e_phdr.e_phdr32 = NULL; } else { free(e->e_u.e_elf.e_ehdr.e_ehdr64); if (e->e_u.e_elf.e_phdr.e_phdr64) free(e->e_u.e_elf.e_phdr.e_phdr64); e->e_u.e_elf.e_ehdr.e_ehdr64 = NULL; e->e_u.e_elf.e_phdr.e_phdr64 = NULL; } return (rc); error: if (newfile) free(newfile); return ((off_t) -1); } off_t elf_update(Elf *e, Elf_Cmd c) { int ec; off_t rc; rc = (off_t) -1; if (e == NULL || e->e_kind != ELF_K_ELF || (c != ELF_C_NULL && c != ELF_C_WRITE)) { LIBELF_SET_ERROR(ARGUMENT, 0); return (rc); } if ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) { LIBELF_SET_ERROR(CLASS, 0); return (rc); } if (e->e_version == EV_NONE) e->e_version = EV_CURRENT; if (c == ELF_C_WRITE && e->e_cmd == ELF_C_READ) { LIBELF_SET_ERROR(MODE, 0); return (rc); } if ((rc = _libelf_resync_elf(e)) < 0) return (rc); if (c == ELF_C_NULL) return (rc); if (e->e_cmd == ELF_C_READ) { /* * This descriptor was opened in read-only mode or by * elf_memory(). */ if (e->e_fd) LIBELF_SET_ERROR(MODE, 0); else LIBELF_SET_ERROR(ARGUMENT, 0); return ((off_t) -1); } if (e->e_fd < 0) { LIBELF_SET_ERROR(SEQUENCE, 0); return ((off_t) -1); } return (_libelf_write_elf(e, rc)); }