/* Free resources associated with Elf descriptor. Copyright (C) 1998,1999,2000,2001,2002,2004,2005,2007,2015,2016 Red Hat, Inc. This file is part of elfutils. Written by Ulrich Drepper , 1998. This file is free software; you can redistribute it and/or modify it under the terms of either * the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version or * the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version or both in parallel, as here. elfutils 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 General Public License for more details. You should have received copies of the GNU General Public License and the GNU Lesser General Public License along with this program. If not, see . */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include #include "libelfP.h" int elf_end (Elf *elf) { Elf *parent; if (elf == NULL) /* This is allowed and is a no-op. */ return 0; /* Make sure we are alone. */ rwlock_wrlock (elf->lock); if (elf->ref_count != 0 && --elf->ref_count != 0) { /* Not yet the last activation. */ int result = elf->ref_count; rwlock_unlock (elf->lock); return result; } if (elf->kind == ELF_K_AR) { /* We cannot remove the descriptor now since we still have some descriptors which depend on it. But we can free the archive symbol table since this is only available via the archive ELF descriptor. The long name table cannot be freed yet since the archive headers for the ELF files in the archive point into this array. */ if (elf->state.ar.ar_sym != (Elf_Arsym *) -1l) free (elf->state.ar.ar_sym); elf->state.ar.ar_sym = NULL; if (elf->state.ar.children != NULL) return 0; } /* Remove this structure from the children list. */ parent = elf->parent; if (parent != NULL) { /* This is tricky. Lock must be acquire from the father to the child but here we already have the child lock. We solve this problem by giving free the child lock. The state of REF_COUNT==0 is handled all over the library, so this should be ok. */ rwlock_unlock (elf->lock); rwlock_rdlock (parent->lock); rwlock_wrlock (elf->lock); if (parent->state.ar.children == elf) parent->state.ar.children = elf->next; else { struct Elf *child = parent->state.ar.children; while (child->next != elf) child = child->next; child->next = elf->next; } rwlock_unlock (parent->lock); } /* This was the last activation. Free all resources. */ switch (elf->kind) { case ELF_K_AR: if (elf->state.ar.long_names != NULL) free (elf->state.ar.long_names); break; case ELF_K_ELF: { Elf_Data_Chunk *rawchunks = (elf->class == ELFCLASS32 || (offsetof (struct Elf, state.elf32.rawchunks) == offsetof (struct Elf, state.elf64.rawchunks)) ? elf->state.elf32.rawchunks : elf->state.elf64.rawchunks); while (rawchunks != NULL) { Elf_Data_Chunk *next = rawchunks->next; if (rawchunks->dummy_scn.flags & ELF_F_MALLOCED) free (rawchunks->data.d.d_buf); free (rawchunks); rawchunks = next; } Elf_ScnList *list = (elf->class == ELFCLASS32 || (offsetof (struct Elf, state.elf32.scns) == offsetof (struct Elf, state.elf64.scns)) ? &elf->state.elf32.scns : &elf->state.elf64.scns); do { /* Free all separately allocated section headers. */ size_t cnt = list->max; while (cnt-- > 0) { /* These pointers can be NULL; it's safe to use 'free' since it will check for this. */ Elf_Scn *scn = &list->data[cnt]; Elf_Data_List *runp; if ((scn->shdr_flags & ELF_F_MALLOCED) != 0) /* It doesn't matter which pointer. */ free (scn->shdr.e32); /* Free zdata if uncompressed, but not yet used as rawdata_base. If it is already used it will be freed below. */ if (scn->zdata_base != scn->rawdata_base) free (scn->zdata_base); /* If the file has the same byte order and the architecture doesn't require overly stringent alignment the raw data buffer is the same as the one used for presenting to the caller. */ if (scn->data_base != scn->rawdata_base) free (scn->data_base); /* The section data is allocated if we couldn't mmap the file. Or if we had to decompress. */ if (elf->map_address == NULL || scn->rawdata_base == scn->zdata_base || (scn->flags & ELF_F_MALLOCED) != 0) free (scn->rawdata_base); /* Free the list of data buffers for the section. We don't free the buffers themselves since this is the users job. */ runp = scn->data_list.next; while (runp != NULL) { Elf_Data_List *oldp = runp; runp = runp->next; if ((oldp->flags & ELF_F_MALLOCED) != 0) free (oldp); } } /* Free the memory for the array. */ Elf_ScnList *oldp = list; list = list->next; assert (list == NULL || oldp->cnt == oldp->max); if (oldp != (elf->class == ELFCLASS32 || (offsetof (struct Elf, state.elf32.scns) == offsetof (struct Elf, state.elf64.scns)) ? &elf->state.elf32.scns : &elf->state.elf64.scns)) free (oldp); } while (list != NULL); } /* Free the section header. */ if (elf->state.elf.shdr_malloced != 0) free (elf->class == ELFCLASS32 || (offsetof (struct Elf, state.elf32.shdr) == offsetof (struct Elf, state.elf64.shdr)) ? (void *) elf->state.elf32.shdr : (void *) elf->state.elf64.shdr); /* Free the program header. */ if ((elf->state.elf.phdr_flags & ELF_F_MALLOCED) != 0) free (elf->class == ELFCLASS32 || (offsetof (struct Elf, state.elf32.phdr) == offsetof (struct Elf, state.elf64.phdr)) ? (void *) elf->state.elf32.phdr : (void *) elf->state.elf64.phdr); break; default: break; } if (elf->map_address != NULL && parent == NULL) { /* The file was read or mapped for this descriptor. */ if ((elf->flags & ELF_F_MALLOCED) != 0) free (elf->map_address); else if ((elf->flags & ELF_F_MMAPPED) != 0) munmap (elf->map_address, elf->maximum_size); } rwlock_unlock (elf->lock); rwlock_fini (elf->lock); /* Finally the descriptor itself. */ free (elf); return (parent != NULL && parent->ref_count == 0 ? INTUSE(elf_end) (parent) : 0); } INTDEF(elf_end)