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![Jesper Juhl](/assets/img/avatar_default.png)
Remove unneeded casts of kmalloc() return value in binfmt_elf. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1089 lines
30 KiB
C
1089 lines
30 KiB
C
/* binfmt_elf_fdpic.c: FDPIC ELF binary format
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*
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* Copyright (C) 2003, 2004 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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* Derived from binfmt_elf.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/stat.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/errno.h>
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#include <linux/signal.h>
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#include <linux/binfmts.h>
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#include <linux/string.h>
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#include <linux/file.h>
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#include <linux/fcntl.h>
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#include <linux/slab.h>
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#include <linux/highmem.h>
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#include <linux/personality.h>
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#include <linux/ptrace.h>
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#include <linux/init.h>
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#include <linux/smp_lock.h>
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#include <linux/elf.h>
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#include <linux/elf-fdpic.h>
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#include <linux/elfcore.h>
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#include <asm/uaccess.h>
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#include <asm/param.h>
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#include <asm/pgalloc.h>
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typedef char *elf_caddr_t;
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#ifndef elf_addr_t
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#define elf_addr_t unsigned long
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#endif
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#if 0
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#define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
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#else
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#define kdebug(fmt, ...) do {} while(0)
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#endif
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MODULE_LICENSE("GPL");
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static int load_elf_fdpic_binary(struct linux_binprm *bprm, struct pt_regs *regs);
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//static int load_elf_fdpic_library(struct file *);
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static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params, struct file *file);
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static int elf_fdpic_map_file(struct elf_fdpic_params *params,
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struct file *file,
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struct mm_struct *mm,
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const char *what);
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static int create_elf_fdpic_tables(struct linux_binprm *bprm,
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struct mm_struct *mm,
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struct elf_fdpic_params *exec_params,
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struct elf_fdpic_params *interp_params);
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#ifndef CONFIG_MMU
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static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm, unsigned long *_sp);
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static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *params,
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struct file *file,
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struct mm_struct *mm);
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#endif
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static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
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struct file *file,
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struct mm_struct *mm);
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static struct linux_binfmt elf_fdpic_format = {
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.module = THIS_MODULE,
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.load_binary = load_elf_fdpic_binary,
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// .load_shlib = load_elf_fdpic_library,
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// .core_dump = elf_fdpic_core_dump,
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.min_coredump = ELF_EXEC_PAGESIZE,
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};
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static int __init init_elf_fdpic_binfmt(void) { return register_binfmt(&elf_fdpic_format); }
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static void __exit exit_elf_fdpic_binfmt(void) { unregister_binfmt(&elf_fdpic_format); }
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module_init(init_elf_fdpic_binfmt)
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module_exit(exit_elf_fdpic_binfmt)
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static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
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{
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if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
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return 0;
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if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
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return 0;
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if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
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return 0;
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if (!file->f_op || !file->f_op->mmap)
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return 0;
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return 1;
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}
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/*****************************************************************************/
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/*
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* read the program headers table into memory
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*/
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static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params, struct file *file)
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{
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struct elf32_phdr *phdr;
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unsigned long size;
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int retval, loop;
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if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
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return -ENOMEM;
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if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
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return -ENOMEM;
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size = params->hdr.e_phnum * sizeof(struct elf_phdr);
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params->phdrs = kmalloc(size, GFP_KERNEL);
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if (!params->phdrs)
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return -ENOMEM;
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retval = kernel_read(file, params->hdr.e_phoff, (char *) params->phdrs, size);
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if (retval < 0)
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return retval;
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/* determine stack size for this binary */
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phdr = params->phdrs;
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for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
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if (phdr->p_type != PT_GNU_STACK)
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continue;
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if (phdr->p_flags & PF_X)
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params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
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else
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params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
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params->stack_size = phdr->p_memsz;
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break;
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}
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return 0;
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} /* end elf_fdpic_fetch_phdrs() */
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/*****************************************************************************/
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/*
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* load an fdpic binary into various bits of memory
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*/
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static int load_elf_fdpic_binary(struct linux_binprm *bprm, struct pt_regs *regs)
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{
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struct elf_fdpic_params exec_params, interp_params;
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struct elf_phdr *phdr;
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unsigned long stack_size;
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struct file *interpreter = NULL; /* to shut gcc up */
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char *interpreter_name = NULL;
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int executable_stack;
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int retval, i;
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memset(&exec_params, 0, sizeof(exec_params));
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memset(&interp_params, 0, sizeof(interp_params));
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exec_params.hdr = *(struct elfhdr *) bprm->buf;
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exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
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/* check that this is a binary we know how to deal with */
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retval = -ENOEXEC;
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if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
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goto error;
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/* read the program header table */
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retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
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if (retval < 0)
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goto error;
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/* scan for a program header that specifies an interpreter */
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phdr = exec_params.phdrs;
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for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
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switch (phdr->p_type) {
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case PT_INTERP:
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retval = -ENOMEM;
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if (phdr->p_filesz > PATH_MAX)
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goto error;
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retval = -ENOENT;
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if (phdr->p_filesz < 2)
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goto error;
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/* read the name of the interpreter into memory */
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interpreter_name = kmalloc(phdr->p_filesz, GFP_KERNEL);
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if (!interpreter_name)
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goto error;
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retval = kernel_read(bprm->file,
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phdr->p_offset,
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interpreter_name,
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phdr->p_filesz);
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if (retval < 0)
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goto error;
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retval = -ENOENT;
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if (interpreter_name[phdr->p_filesz - 1] != '\0')
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goto error;
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kdebug("Using ELF interpreter %s", interpreter_name);
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/* replace the program with the interpreter */
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interpreter = open_exec(interpreter_name);
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retval = PTR_ERR(interpreter);
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if (IS_ERR(interpreter)) {
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interpreter = NULL;
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goto error;
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}
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retval = kernel_read(interpreter, 0, bprm->buf, BINPRM_BUF_SIZE);
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if (retval < 0)
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goto error;
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interp_params.hdr = *((struct elfhdr *) bprm->buf);
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break;
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case PT_LOAD:
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#ifdef CONFIG_MMU
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if (exec_params.load_addr == 0)
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exec_params.load_addr = phdr->p_vaddr;
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#endif
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break;
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}
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}
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if (elf_check_const_displacement(&exec_params.hdr))
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exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
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/* perform insanity checks on the interpreter */
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if (interpreter_name) {
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retval = -ELIBBAD;
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if (!is_elf_fdpic(&interp_params.hdr, interpreter))
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goto error;
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interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
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/* read the interpreter's program header table */
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retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
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if (retval < 0)
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goto error;
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}
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stack_size = exec_params.stack_size;
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if (stack_size < interp_params.stack_size)
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stack_size = interp_params.stack_size;
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if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
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executable_stack = EXSTACK_ENABLE_X;
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else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
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executable_stack = EXSTACK_DISABLE_X;
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else if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
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executable_stack = EXSTACK_ENABLE_X;
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else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
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executable_stack = EXSTACK_DISABLE_X;
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else
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executable_stack = EXSTACK_DEFAULT;
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retval = -ENOEXEC;
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if (stack_size == 0)
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goto error;
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if (elf_check_const_displacement(&interp_params.hdr))
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interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
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/* flush all traces of the currently running executable */
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retval = flush_old_exec(bprm);
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if (retval)
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goto error;
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/* there's now no turning back... the old userspace image is dead,
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* defunct, deceased, etc. after this point we have to exit via
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* error_kill */
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set_personality(PER_LINUX_FDPIC);
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set_binfmt(&elf_fdpic_format);
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current->mm->start_code = 0;
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current->mm->end_code = 0;
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current->mm->start_stack = 0;
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current->mm->start_data = 0;
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current->mm->end_data = 0;
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current->mm->context.exec_fdpic_loadmap = 0;
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current->mm->context.interp_fdpic_loadmap = 0;
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current->flags &= ~PF_FORKNOEXEC;
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#ifdef CONFIG_MMU
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elf_fdpic_arch_lay_out_mm(&exec_params,
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&interp_params,
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¤t->mm->start_stack,
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¤t->mm->start_brk);
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retval = setup_arg_pages(bprm, current->mm->start_stack, executable_stack);
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if (retval < 0) {
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send_sig(SIGKILL, current, 0);
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goto error_kill;
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}
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#endif
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/* load the executable and interpreter into memory */
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retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm, "executable");
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if (retval < 0)
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goto error_kill;
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if (interpreter_name) {
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retval = elf_fdpic_map_file(&interp_params, interpreter,
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current->mm, "interpreter");
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if (retval < 0) {
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printk(KERN_ERR "Unable to load interpreter\n");
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goto error_kill;
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}
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allow_write_access(interpreter);
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fput(interpreter);
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interpreter = NULL;
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}
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#ifdef CONFIG_MMU
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if (!current->mm->start_brk)
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current->mm->start_brk = current->mm->end_data;
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current->mm->brk = current->mm->start_brk = PAGE_ALIGN(current->mm->start_brk);
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#else
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/* create a stack and brk area big enough for everyone
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* - the brk heap starts at the bottom and works up
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* - the stack starts at the top and works down
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*/
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stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
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if (stack_size < PAGE_SIZE * 2)
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stack_size = PAGE_SIZE * 2;
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down_write(¤t->mm->mmap_sem);
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current->mm->start_brk = do_mmap(NULL,
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0,
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stack_size,
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PROT_READ | PROT_WRITE | PROT_EXEC,
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MAP_PRIVATE | MAP_ANON | MAP_GROWSDOWN,
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0);
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if (IS_ERR((void *) current->mm->start_brk)) {
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up_write(¤t->mm->mmap_sem);
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retval = current->mm->start_brk;
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current->mm->start_brk = 0;
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goto error_kill;
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}
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if (do_mremap(current->mm->start_brk,
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stack_size,
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ksize((char *) current->mm->start_brk),
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0, 0
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) == current->mm->start_brk
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)
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stack_size = ksize((char *) current->mm->start_brk);
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up_write(¤t->mm->mmap_sem);
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current->mm->brk = current->mm->start_brk;
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current->mm->context.end_brk = current->mm->start_brk;
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current->mm->context.end_brk += (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
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current->mm->start_stack = current->mm->start_brk + stack_size;
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#endif
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compute_creds(bprm);
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current->flags &= ~PF_FORKNOEXEC;
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if (create_elf_fdpic_tables(bprm, current->mm, &exec_params, &interp_params) < 0)
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goto error_kill;
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kdebug("- start_code %lx", (long) current->mm->start_code);
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kdebug("- end_code %lx", (long) current->mm->end_code);
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kdebug("- start_data %lx", (long) current->mm->start_data);
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kdebug("- end_data %lx", (long) current->mm->end_data);
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kdebug("- start_brk %lx", (long) current->mm->start_brk);
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kdebug("- brk %lx", (long) current->mm->brk);
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kdebug("- start_stack %lx", (long) current->mm->start_stack);
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|
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#ifdef ELF_FDPIC_PLAT_INIT
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/*
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* The ABI may specify that certain registers be set up in special
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* ways (on i386 %edx is the address of a DT_FINI function, for
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* example. This macro performs whatever initialization to
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* the regs structure is required.
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*/
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ELF_FDPIC_PLAT_INIT(regs,
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exec_params.map_addr,
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interp_params.map_addr,
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interp_params.dynamic_addr ?: exec_params.dynamic_addr
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);
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#endif
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|
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/* everything is now ready... get the userspace context ready to roll */
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start_thread(regs,
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interp_params.entry_addr ?: exec_params.entry_addr,
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current->mm->start_stack);
|
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|
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if (unlikely(current->ptrace & PT_PTRACED)) {
|
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if (current->ptrace & PT_TRACE_EXEC)
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ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
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else
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send_sig(SIGTRAP, current, 0);
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}
|
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|
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retval = 0;
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|
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error:
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if (interpreter) {
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allow_write_access(interpreter);
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fput(interpreter);
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}
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kfree(interpreter_name);
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kfree(exec_params.phdrs);
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kfree(exec_params.loadmap);
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kfree(interp_params.phdrs);
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kfree(interp_params.loadmap);
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return retval;
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|
|
/* unrecoverable error - kill the process */
|
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error_kill:
|
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send_sig(SIGSEGV, current, 0);
|
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goto error;
|
|
|
|
} /* end load_elf_fdpic_binary() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
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* present useful information to the program
|
|
*/
|
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static int create_elf_fdpic_tables(struct linux_binprm *bprm,
|
|
struct mm_struct *mm,
|
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struct elf_fdpic_params *exec_params,
|
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struct elf_fdpic_params *interp_params)
|
|
{
|
|
unsigned long sp, csp, nitems;
|
|
elf_caddr_t *argv, *envp;
|
|
size_t platform_len = 0, len;
|
|
char *k_platform, *u_platform, *p;
|
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long hwcap;
|
|
int loop;
|
|
|
|
/* we're going to shovel a whole load of stuff onto the stack */
|
|
#ifdef CONFIG_MMU
|
|
sp = bprm->p;
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|
#else
|
|
sp = mm->start_stack;
|
|
|
|
/* stack the program arguments and environment */
|
|
if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
|
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return -EFAULT;
|
|
#endif
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|
|
|
/* get hold of platform and hardware capabilities masks for the machine
|
|
* we are running on. In some cases (Sparc), this info is impossible
|
|
* to get, in others (i386) it is merely difficult.
|
|
*/
|
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hwcap = ELF_HWCAP;
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k_platform = ELF_PLATFORM;
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|
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if (k_platform) {
|
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platform_len = strlen(k_platform) + 1;
|
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sp -= platform_len;
|
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if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
|
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return -EFAULT;
|
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}
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|
|
u_platform = (char *) sp;
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|
|
#if defined(__i386__) && defined(CONFIG_SMP)
|
|
/* in some cases (e.g. Hyper-Threading), we want to avoid L1 evictions
|
|
* by the processes running on the same package. One thing we can do
|
|
* is to shuffle the initial stack for them.
|
|
*
|
|
* the conditionals here are unneeded, but kept in to make the
|
|
* code behaviour the same as pre change unless we have hyperthreaded
|
|
* processors. This keeps Mr Marcelo Person happier but should be
|
|
* removed for 2.5
|
|
*/
|
|
if (smp_num_siblings > 1)
|
|
sp = sp - ((current->pid % 64) << 7);
|
|
#endif
|
|
|
|
sp &= ~7UL;
|
|
|
|
/* stack the load map(s) */
|
|
len = sizeof(struct elf32_fdpic_loadmap);
|
|
len += sizeof(struct elf32_fdpic_loadseg) * exec_params->loadmap->nsegs;
|
|
sp = (sp - len) & ~7UL;
|
|
exec_params->map_addr = sp;
|
|
|
|
if (copy_to_user((void *) sp, exec_params->loadmap, len) != 0)
|
|
return -EFAULT;
|
|
|
|
current->mm->context.exec_fdpic_loadmap = (unsigned long) sp;
|
|
|
|
if (interp_params->loadmap) {
|
|
len = sizeof(struct elf32_fdpic_loadmap);
|
|
len += sizeof(struct elf32_fdpic_loadseg) * interp_params->loadmap->nsegs;
|
|
sp = (sp - len) & ~7UL;
|
|
interp_params->map_addr = sp;
|
|
|
|
if (copy_to_user((void *) sp, interp_params->loadmap, len) != 0)
|
|
return -EFAULT;
|
|
|
|
current->mm->context.interp_fdpic_loadmap = (unsigned long) sp;
|
|
}
|
|
|
|
/* force 16 byte _final_ alignment here for generality */
|
|
#define DLINFO_ITEMS 13
|
|
|
|
nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0);
|
|
#ifdef DLINFO_ARCH_ITEMS
|
|
nitems += DLINFO_ARCH_ITEMS;
|
|
#endif
|
|
|
|
csp = sp;
|
|
sp -= nitems * 2 * sizeof(unsigned long);
|
|
sp -= (bprm->envc + 1) * sizeof(char *); /* envv[] */
|
|
sp -= (bprm->argc + 1) * sizeof(char *); /* argv[] */
|
|
sp -= 1 * sizeof(unsigned long); /* argc */
|
|
|
|
csp -= sp & 15UL;
|
|
sp -= sp & 15UL;
|
|
|
|
/* put the ELF interpreter info on the stack */
|
|
#define NEW_AUX_ENT(nr, id, val) \
|
|
do { \
|
|
struct { unsigned long _id, _val; } *ent = (void *) csp; \
|
|
__put_user((id), &ent[nr]._id); \
|
|
__put_user((val), &ent[nr]._val); \
|
|
} while (0)
|
|
|
|
csp -= 2 * sizeof(unsigned long);
|
|
NEW_AUX_ENT(0, AT_NULL, 0);
|
|
if (k_platform) {
|
|
csp -= 2 * sizeof(unsigned long);
|
|
NEW_AUX_ENT(0, AT_PLATFORM, (elf_addr_t)(unsigned long) u_platform);
|
|
}
|
|
|
|
csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long);
|
|
NEW_AUX_ENT( 0, AT_HWCAP, hwcap);
|
|
NEW_AUX_ENT( 1, AT_PAGESZ, PAGE_SIZE);
|
|
NEW_AUX_ENT( 2, AT_CLKTCK, CLOCKS_PER_SEC);
|
|
NEW_AUX_ENT( 3, AT_PHDR, exec_params->ph_addr);
|
|
NEW_AUX_ENT( 4, AT_PHENT, sizeof(struct elf_phdr));
|
|
NEW_AUX_ENT( 5, AT_PHNUM, exec_params->hdr.e_phnum);
|
|
NEW_AUX_ENT( 6, AT_BASE, interp_params->elfhdr_addr);
|
|
NEW_AUX_ENT( 7, AT_FLAGS, 0);
|
|
NEW_AUX_ENT( 8, AT_ENTRY, exec_params->entry_addr);
|
|
NEW_AUX_ENT( 9, AT_UID, (elf_addr_t) current->uid);
|
|
NEW_AUX_ENT(10, AT_EUID, (elf_addr_t) current->euid);
|
|
NEW_AUX_ENT(11, AT_GID, (elf_addr_t) current->gid);
|
|
NEW_AUX_ENT(12, AT_EGID, (elf_addr_t) current->egid);
|
|
|
|
#ifdef ARCH_DLINFO
|
|
/* ARCH_DLINFO must come last so platform specific code can enforce
|
|
* special alignment requirements on the AUXV if necessary (eg. PPC).
|
|
*/
|
|
ARCH_DLINFO;
|
|
#endif
|
|
#undef NEW_AUX_ENT
|
|
|
|
/* allocate room for argv[] and envv[] */
|
|
csp -= (bprm->envc + 1) * sizeof(elf_caddr_t);
|
|
envp = (elf_caddr_t *) csp;
|
|
csp -= (bprm->argc + 1) * sizeof(elf_caddr_t);
|
|
argv = (elf_caddr_t *) csp;
|
|
|
|
/* stack argc */
|
|
csp -= sizeof(unsigned long);
|
|
__put_user(bprm->argc, (unsigned long *) csp);
|
|
|
|
if (csp != sp)
|
|
BUG();
|
|
|
|
/* fill in the argv[] array */
|
|
#ifdef CONFIG_MMU
|
|
current->mm->arg_start = bprm->p;
|
|
#else
|
|
current->mm->arg_start = current->mm->start_stack - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p);
|
|
#endif
|
|
|
|
p = (char *) current->mm->arg_start;
|
|
for (loop = bprm->argc; loop > 0; loop--) {
|
|
__put_user((elf_caddr_t) p, argv++);
|
|
len = strnlen_user(p, PAGE_SIZE * MAX_ARG_PAGES);
|
|
if (!len || len > PAGE_SIZE * MAX_ARG_PAGES)
|
|
return -EINVAL;
|
|
p += len;
|
|
}
|
|
__put_user(NULL, argv);
|
|
current->mm->arg_end = (unsigned long) p;
|
|
|
|
/* fill in the envv[] array */
|
|
current->mm->env_start = (unsigned long) p;
|
|
for (loop = bprm->envc; loop > 0; loop--) {
|
|
__put_user((elf_caddr_t)(unsigned long) p, envp++);
|
|
len = strnlen_user(p, PAGE_SIZE * MAX_ARG_PAGES);
|
|
if (!len || len > PAGE_SIZE * MAX_ARG_PAGES)
|
|
return -EINVAL;
|
|
p += len;
|
|
}
|
|
__put_user(NULL, envp);
|
|
current->mm->env_end = (unsigned long) p;
|
|
|
|
mm->start_stack = (unsigned long) sp;
|
|
return 0;
|
|
} /* end create_elf_fdpic_tables() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* transfer the program arguments and environment from the holding pages onto
|
|
* the stack
|
|
*/
|
|
#ifndef CONFIG_MMU
|
|
static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm, unsigned long *_sp)
|
|
{
|
|
unsigned long index, stop, sp;
|
|
char *src;
|
|
int ret = 0;
|
|
|
|
stop = bprm->p >> PAGE_SHIFT;
|
|
sp = *_sp;
|
|
|
|
for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
|
|
src = kmap(bprm->page[index]);
|
|
sp -= PAGE_SIZE;
|
|
if (copy_to_user((void *) sp, src, PAGE_SIZE) != 0)
|
|
ret = -EFAULT;
|
|
kunmap(bprm->page[index]);
|
|
if (ret < 0)
|
|
goto out;
|
|
}
|
|
|
|
*_sp = (*_sp - (MAX_ARG_PAGES * PAGE_SIZE - bprm->p)) & ~15;
|
|
|
|
out:
|
|
return ret;
|
|
} /* end elf_fdpic_transfer_args_to_stack() */
|
|
#endif
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* load the appropriate binary image (executable or interpreter) into memory
|
|
* - we assume no MMU is available
|
|
* - if no other PIC bits are set in params->hdr->e_flags
|
|
* - we assume that the LOADable segments in the binary are independently relocatable
|
|
* - we assume R/O executable segments are shareable
|
|
* - else
|
|
* - we assume the loadable parts of the image to require fixed displacement
|
|
* - the image is not shareable
|
|
*/
|
|
static int elf_fdpic_map_file(struct elf_fdpic_params *params,
|
|
struct file *file,
|
|
struct mm_struct *mm,
|
|
const char *what)
|
|
{
|
|
struct elf32_fdpic_loadmap *loadmap;
|
|
#ifdef CONFIG_MMU
|
|
struct elf32_fdpic_loadseg *mseg;
|
|
#endif
|
|
struct elf32_fdpic_loadseg *seg;
|
|
struct elf32_phdr *phdr;
|
|
unsigned long load_addr, stop;
|
|
unsigned nloads, tmp;
|
|
size_t size;
|
|
int loop, ret;
|
|
|
|
/* allocate a load map table */
|
|
nloads = 0;
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++)
|
|
if (params->phdrs[loop].p_type == PT_LOAD)
|
|
nloads++;
|
|
|
|
if (nloads == 0)
|
|
return -ELIBBAD;
|
|
|
|
size = sizeof(*loadmap) + nloads * sizeof(*seg);
|
|
loadmap = kmalloc(size, GFP_KERNEL);
|
|
if (!loadmap)
|
|
return -ENOMEM;
|
|
|
|
params->loadmap = loadmap;
|
|
memset(loadmap, 0, size);
|
|
|
|
loadmap->version = ELF32_FDPIC_LOADMAP_VERSION;
|
|
loadmap->nsegs = nloads;
|
|
|
|
load_addr = params->load_addr;
|
|
seg = loadmap->segs;
|
|
|
|
/* map the requested LOADs into the memory space */
|
|
switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
|
|
case ELF_FDPIC_FLAG_CONSTDISP:
|
|
case ELF_FDPIC_FLAG_CONTIGUOUS:
|
|
#ifndef CONFIG_MMU
|
|
ret = elf_fdpic_map_file_constdisp_on_uclinux(params, file, mm);
|
|
if (ret < 0)
|
|
return ret;
|
|
break;
|
|
#endif
|
|
default:
|
|
ret = elf_fdpic_map_file_by_direct_mmap(params, file, mm);
|
|
if (ret < 0)
|
|
return ret;
|
|
break;
|
|
}
|
|
|
|
/* map the entry point */
|
|
if (params->hdr.e_entry) {
|
|
seg = loadmap->segs;
|
|
for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
|
|
if (params->hdr.e_entry >= seg->p_vaddr &&
|
|
params->hdr.e_entry < seg->p_vaddr + seg->p_memsz
|
|
) {
|
|
params->entry_addr =
|
|
(params->hdr.e_entry - seg->p_vaddr) + seg->addr;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* determine where the program header table has wound up if mapped */
|
|
stop = params->hdr.e_phoff + params->hdr.e_phnum * sizeof (struct elf_phdr);
|
|
phdr = params->phdrs;
|
|
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
|
|
if (phdr->p_type != PT_LOAD)
|
|
continue;
|
|
|
|
if (phdr->p_offset > params->hdr.e_phoff ||
|
|
phdr->p_offset + phdr->p_filesz < stop)
|
|
continue;
|
|
|
|
seg = loadmap->segs;
|
|
for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
|
|
if (phdr->p_vaddr >= seg->p_vaddr &&
|
|
phdr->p_vaddr + phdr->p_filesz <= seg->p_vaddr + seg->p_memsz
|
|
) {
|
|
params->ph_addr = (phdr->p_vaddr - seg->p_vaddr) + seg->addr +
|
|
params->hdr.e_phoff - phdr->p_offset;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* determine where the dynamic section has wound up if there is one */
|
|
phdr = params->phdrs;
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
|
|
if (phdr->p_type != PT_DYNAMIC)
|
|
continue;
|
|
|
|
seg = loadmap->segs;
|
|
for (loop = loadmap->nsegs; loop > 0; loop--, seg++) {
|
|
if (phdr->p_vaddr >= seg->p_vaddr &&
|
|
phdr->p_vaddr + phdr->p_memsz <= seg->p_vaddr + seg->p_memsz
|
|
) {
|
|
params->dynamic_addr = (phdr->p_vaddr - seg->p_vaddr) + seg->addr;
|
|
|
|
/* check the dynamic section contains at least one item, and that
|
|
* the last item is a NULL entry */
|
|
if (phdr->p_memsz == 0 ||
|
|
phdr->p_memsz % sizeof(Elf32_Dyn) != 0)
|
|
goto dynamic_error;
|
|
|
|
tmp = phdr->p_memsz / sizeof(Elf32_Dyn);
|
|
if (((Elf32_Dyn *) params->dynamic_addr)[tmp - 1].d_tag != 0)
|
|
goto dynamic_error;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* now elide adjacent segments in the load map on MMU linux
|
|
* - on uClinux the holes between may actually be filled with system stuff or stuff from
|
|
* other processes
|
|
*/
|
|
#ifdef CONFIG_MMU
|
|
nloads = loadmap->nsegs;
|
|
mseg = loadmap->segs;
|
|
seg = mseg + 1;
|
|
for (loop = 1; loop < nloads; loop++) {
|
|
/* see if we have a candidate for merging */
|
|
if (seg->p_vaddr - mseg->p_vaddr == seg->addr - mseg->addr) {
|
|
load_addr = PAGE_ALIGN(mseg->addr + mseg->p_memsz);
|
|
if (load_addr == (seg->addr & PAGE_MASK)) {
|
|
mseg->p_memsz += load_addr - (mseg->addr + mseg->p_memsz);
|
|
mseg->p_memsz += seg->addr & ~PAGE_MASK;
|
|
mseg->p_memsz += seg->p_memsz;
|
|
loadmap->nsegs--;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
mseg++;
|
|
if (mseg != seg)
|
|
*mseg = *seg;
|
|
}
|
|
#endif
|
|
|
|
kdebug("Mapped Object [%s]:", what);
|
|
kdebug("- elfhdr : %lx", params->elfhdr_addr);
|
|
kdebug("- entry : %lx", params->entry_addr);
|
|
kdebug("- PHDR[] : %lx", params->ph_addr);
|
|
kdebug("- DYNAMIC[]: %lx", params->dynamic_addr);
|
|
seg = loadmap->segs;
|
|
for (loop = 0; loop < loadmap->nsegs; loop++, seg++)
|
|
kdebug("- LOAD[%d] : %08x-%08x [va=%x ms=%x]",
|
|
loop,
|
|
seg->addr, seg->addr + seg->p_memsz - 1,
|
|
seg->p_vaddr, seg->p_memsz);
|
|
|
|
return 0;
|
|
|
|
dynamic_error:
|
|
printk("ELF FDPIC %s with invalid DYNAMIC section (inode=%lu)\n",
|
|
what, file->f_dentry->d_inode->i_ino);
|
|
return -ELIBBAD;
|
|
} /* end elf_fdpic_map_file() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* map a file with constant displacement under uClinux
|
|
*/
|
|
#ifndef CONFIG_MMU
|
|
static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *params,
|
|
struct file *file,
|
|
struct mm_struct *mm)
|
|
{
|
|
struct elf32_fdpic_loadseg *seg;
|
|
struct elf32_phdr *phdr;
|
|
unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
|
|
loff_t fpos;
|
|
int loop, ret;
|
|
|
|
load_addr = params->load_addr;
|
|
seg = params->loadmap->segs;
|
|
|
|
/* determine the bounds of the contiguous overall allocation we must make */
|
|
phdr = params->phdrs;
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
|
|
if (params->phdrs[loop].p_type != PT_LOAD)
|
|
continue;
|
|
|
|
if (base > phdr->p_vaddr)
|
|
base = phdr->p_vaddr;
|
|
if (top < phdr->p_vaddr + phdr->p_memsz)
|
|
top = phdr->p_vaddr + phdr->p_memsz;
|
|
}
|
|
|
|
/* allocate one big anon block for everything */
|
|
mflags = MAP_PRIVATE;
|
|
if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
|
|
mflags |= MAP_EXECUTABLE;
|
|
|
|
down_write(&mm->mmap_sem);
|
|
maddr = do_mmap(NULL, load_addr, top - base,
|
|
PROT_READ | PROT_WRITE | PROT_EXEC, mflags, 0);
|
|
up_write(&mm->mmap_sem);
|
|
if (IS_ERR((void *) maddr))
|
|
return (int) maddr;
|
|
|
|
if (load_addr != 0)
|
|
load_addr += PAGE_ALIGN(top - base);
|
|
|
|
/* and then load the file segments into it */
|
|
phdr = params->phdrs;
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
|
|
if (params->phdrs[loop].p_type != PT_LOAD)
|
|
continue;
|
|
|
|
fpos = phdr->p_offset;
|
|
|
|
seg->addr = maddr + (phdr->p_vaddr - base);
|
|
seg->p_vaddr = phdr->p_vaddr;
|
|
seg->p_memsz = phdr->p_memsz;
|
|
|
|
ret = file->f_op->read(file, (void *) seg->addr, phdr->p_filesz, &fpos);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* map the ELF header address if in this segment */
|
|
if (phdr->p_offset == 0)
|
|
params->elfhdr_addr = seg->addr;
|
|
|
|
/* clear any space allocated but not loaded */
|
|
if (phdr->p_filesz < phdr->p_memsz)
|
|
clear_user((void *) (seg->addr + phdr->p_filesz),
|
|
phdr->p_memsz - phdr->p_filesz);
|
|
|
|
if (mm) {
|
|
if (phdr->p_flags & PF_X) {
|
|
mm->start_code = seg->addr;
|
|
mm->end_code = seg->addr + phdr->p_memsz;
|
|
}
|
|
else if (!mm->start_data) {
|
|
mm->start_data = seg->addr;
|
|
#ifndef CONFIG_MMU
|
|
mm->end_data = seg->addr + phdr->p_memsz;
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
if (seg->addr + phdr->p_memsz > mm->end_data)
|
|
mm->end_data = seg->addr + phdr->p_memsz;
|
|
#endif
|
|
}
|
|
|
|
seg++;
|
|
}
|
|
|
|
return 0;
|
|
} /* end elf_fdpic_map_file_constdisp_on_uclinux() */
|
|
#endif
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* map a binary by direct mmap() of the individual PT_LOAD segments
|
|
*/
|
|
static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
|
|
struct file *file,
|
|
struct mm_struct *mm)
|
|
{
|
|
struct elf32_fdpic_loadseg *seg;
|
|
struct elf32_phdr *phdr;
|
|
unsigned long load_addr, delta_vaddr;
|
|
int loop, dvset;
|
|
|
|
load_addr = params->load_addr;
|
|
delta_vaddr = 0;
|
|
dvset = 0;
|
|
|
|
seg = params->loadmap->segs;
|
|
|
|
/* deal with each load segment separately */
|
|
phdr = params->phdrs;
|
|
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
|
|
unsigned long maddr, disp, excess, excess1;
|
|
int prot = 0, flags;
|
|
|
|
if (phdr->p_type != PT_LOAD)
|
|
continue;
|
|
|
|
kdebug("[LOAD] va=%lx of=%lx fs=%lx ms=%lx",
|
|
(unsigned long) phdr->p_vaddr,
|
|
(unsigned long) phdr->p_offset,
|
|
(unsigned long) phdr->p_filesz,
|
|
(unsigned long) phdr->p_memsz);
|
|
|
|
/* determine the mapping parameters */
|
|
if (phdr->p_flags & PF_R) prot |= PROT_READ;
|
|
if (phdr->p_flags & PF_W) prot |= PROT_WRITE;
|
|
if (phdr->p_flags & PF_X) prot |= PROT_EXEC;
|
|
|
|
flags = MAP_PRIVATE | MAP_DENYWRITE;
|
|
if (params->flags & ELF_FDPIC_FLAG_EXECUTABLE)
|
|
flags |= MAP_EXECUTABLE;
|
|
|
|
maddr = 0;
|
|
|
|
switch (params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) {
|
|
case ELF_FDPIC_FLAG_INDEPENDENT:
|
|
/* PT_LOADs are independently locatable */
|
|
break;
|
|
|
|
case ELF_FDPIC_FLAG_HONOURVADDR:
|
|
/* the specified virtual address must be honoured */
|
|
maddr = phdr->p_vaddr;
|
|
flags |= MAP_FIXED;
|
|
break;
|
|
|
|
case ELF_FDPIC_FLAG_CONSTDISP:
|
|
/* constant displacement
|
|
* - can be mapped anywhere, but must be mapped as a unit
|
|
*/
|
|
if (!dvset) {
|
|
maddr = load_addr;
|
|
delta_vaddr = phdr->p_vaddr;
|
|
dvset = 1;
|
|
}
|
|
else {
|
|
maddr = load_addr + phdr->p_vaddr - delta_vaddr;
|
|
flags |= MAP_FIXED;
|
|
}
|
|
break;
|
|
|
|
case ELF_FDPIC_FLAG_CONTIGUOUS:
|
|
/* contiguity handled later */
|
|
break;
|
|
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
maddr &= PAGE_MASK;
|
|
|
|
/* create the mapping */
|
|
disp = phdr->p_vaddr & ~PAGE_MASK;
|
|
down_write(&mm->mmap_sem);
|
|
maddr = do_mmap(file, maddr, phdr->p_memsz + disp, prot, flags,
|
|
phdr->p_offset - disp);
|
|
up_write(&mm->mmap_sem);
|
|
|
|
kdebug("mmap[%d] <file> sz=%lx pr=%x fl=%x of=%lx --> %08lx",
|
|
loop, phdr->p_memsz + disp, prot, flags, phdr->p_offset - disp,
|
|
maddr);
|
|
|
|
if (IS_ERR((void *) maddr))
|
|
return (int) maddr;
|
|
|
|
if ((params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == ELF_FDPIC_FLAG_CONTIGUOUS)
|
|
load_addr += PAGE_ALIGN(phdr->p_memsz + disp);
|
|
|
|
seg->addr = maddr + disp;
|
|
seg->p_vaddr = phdr->p_vaddr;
|
|
seg->p_memsz = phdr->p_memsz;
|
|
|
|
/* map the ELF header address if in this segment */
|
|
if (phdr->p_offset == 0)
|
|
params->elfhdr_addr = seg->addr;
|
|
|
|
/* clear the bit between beginning of mapping and beginning of PT_LOAD */
|
|
if (prot & PROT_WRITE && disp > 0) {
|
|
kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
|
|
clear_user((void *) maddr, disp);
|
|
maddr += disp;
|
|
}
|
|
|
|
/* clear any space allocated but not loaded
|
|
* - on uClinux we can just clear the lot
|
|
* - on MMU linux we'll get a SIGBUS beyond the last page
|
|
* extant in the file
|
|
*/
|
|
excess = phdr->p_memsz - phdr->p_filesz;
|
|
excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
|
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
if (excess > excess1) {
|
|
unsigned long xaddr = maddr + phdr->p_filesz + excess1;
|
|
unsigned long xmaddr;
|
|
|
|
flags |= MAP_FIXED | MAP_ANONYMOUS;
|
|
down_write(&mm->mmap_sem);
|
|
xmaddr = do_mmap(NULL, xaddr, excess - excess1, prot, flags, 0);
|
|
up_write(&mm->mmap_sem);
|
|
|
|
kdebug("mmap[%d] <anon>"
|
|
" ad=%lx sz=%lx pr=%x fl=%x of=0 --> %08lx",
|
|
loop, xaddr, excess - excess1, prot, flags, xmaddr);
|
|
|
|
if (xmaddr != xaddr)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (prot & PROT_WRITE && excess1 > 0) {
|
|
kdebug("clear[%d] ad=%lx sz=%lx",
|
|
loop, maddr + phdr->p_filesz, excess1);
|
|
clear_user((void *) maddr + phdr->p_filesz, excess1);
|
|
}
|
|
|
|
#else
|
|
if (excess > 0) {
|
|
kdebug("clear[%d] ad=%lx sz=%lx",
|
|
loop, maddr + phdr->p_filesz, excess);
|
|
clear_user((void *) maddr + phdr->p_filesz, excess);
|
|
}
|
|
#endif
|
|
|
|
if (mm) {
|
|
if (phdr->p_flags & PF_X) {
|
|
mm->start_code = maddr;
|
|
mm->end_code = maddr + phdr->p_memsz;
|
|
}
|
|
else if (!mm->start_data) {
|
|
mm->start_data = maddr;
|
|
mm->end_data = maddr + phdr->p_memsz;
|
|
}
|
|
}
|
|
|
|
seg++;
|
|
}
|
|
|
|
return 0;
|
|
} /* end elf_fdpic_map_file_by_direct_mmap() */
|