summaryrefslogtreecommitdiff
path: root/fs/binfmt_elf_fdpic.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/binfmt_elf_fdpic.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/binfmt_elf_fdpic.c')
-rw-r--r--fs/binfmt_elf_fdpic.c1101
1 files changed, 1101 insertions, 0 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
new file mode 100644
index 000000000000..134c9c0d1f54
--- /dev/null
+++ b/fs/binfmt_elf_fdpic.c
@@ -0,0 +1,1101 @@
+/* binfmt_elf_fdpic.c: FDPIC ELF binary format
+ *
+ * Copyright (C) 2003, 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * Derived from binfmt_elf.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of 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.
+ */
+
+#include <linux/module.h>
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/binfmts.h>
+#include <linux/string.h>
+#include <linux/file.h>
+#include <linux/fcntl.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/personality.h>
+#include <linux/ptrace.h>
+#include <linux/init.h>
+#include <linux/smp_lock.h>
+#include <linux/elf.h>
+#include <linux/elf-fdpic.h>
+#include <linux/elfcore.h>
+
+#include <asm/uaccess.h>
+#include <asm/param.h>
+#include <asm/pgalloc.h>
+
+typedef char *elf_caddr_t;
+#ifndef elf_addr_t
+#define elf_addr_t unsigned long
+#endif
+
+#if 0
+#define kdebug(fmt, ...) printk("FDPIC "fmt"\n" ,##__VA_ARGS__ )
+#else
+#define kdebug(fmt, ...) do {} while(0)
+#endif
+
+MODULE_LICENSE("GPL");
+
+static int load_elf_fdpic_binary(struct linux_binprm *bprm, struct pt_regs *regs);
+//static int load_elf_fdpic_library(struct file *);
+static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params, struct file *file);
+static int elf_fdpic_map_file(struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm,
+ const char *what);
+
+static int create_elf_fdpic_tables(struct linux_binprm *bprm,
+ struct mm_struct *mm,
+ struct elf_fdpic_params *exec_params,
+ struct elf_fdpic_params *interp_params);
+
+#ifndef CONFIG_MMU
+static int elf_fdpic_transfer_args_to_stack(struct linux_binprm *bprm, unsigned long *_sp);
+static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm);
+#endif
+
+static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
+ struct file *file,
+ struct mm_struct *mm);
+
+static struct linux_binfmt elf_fdpic_format = {
+ .module = THIS_MODULE,
+ .load_binary = load_elf_fdpic_binary,
+// .load_shlib = load_elf_fdpic_library,
+// .core_dump = elf_fdpic_core_dump,
+ .min_coredump = ELF_EXEC_PAGESIZE,
+};
+
+static int __init init_elf_fdpic_binfmt(void) { return register_binfmt(&elf_fdpic_format); }
+static void __exit exit_elf_fdpic_binfmt(void) { unregister_binfmt(&elf_fdpic_format); }
+
+module_init(init_elf_fdpic_binfmt)
+module_exit(exit_elf_fdpic_binfmt)
+
+static int is_elf_fdpic(struct elfhdr *hdr, struct file *file)
+{
+ if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0)
+ return 0;
+ if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)
+ return 0;
+ if (!elf_check_arch(hdr) || !elf_check_fdpic(hdr))
+ return 0;
+ if (!file->f_op || !file->f_op->mmap)
+ return 0;
+ return 1;
+}
+
+/*****************************************************************************/
+/*
+ * read the program headers table into memory
+ */
+static int elf_fdpic_fetch_phdrs(struct elf_fdpic_params *params, struct file *file)
+{
+ struct elf32_phdr *phdr;
+ unsigned long size;
+ int retval, loop;
+
+ if (params->hdr.e_phentsize != sizeof(struct elf_phdr))
+ return -ENOMEM;
+ if (params->hdr.e_phnum > 65536U / sizeof(struct elf_phdr))
+ return -ENOMEM;
+
+ size = params->hdr.e_phnum * sizeof(struct elf_phdr);
+ params->phdrs = kmalloc(size, GFP_KERNEL);
+ if (!params->phdrs)
+ return -ENOMEM;
+
+ retval = kernel_read(file, params->hdr.e_phoff, (char *) params->phdrs, size);
+ if (retval < 0)
+ return retval;
+
+ /* determine stack size for this binary */
+ phdr = params->phdrs;
+ for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
+ if (phdr->p_type != PT_GNU_STACK)
+ continue;
+
+ if (phdr->p_flags & PF_X)
+ params->flags |= ELF_FDPIC_FLAG_EXEC_STACK;
+ else
+ params->flags |= ELF_FDPIC_FLAG_NOEXEC_STACK;
+
+ params->stack_size = phdr->p_memsz;
+ break;
+ }
+
+ return 0;
+} /* end elf_fdpic_fetch_phdrs() */
+
+/*****************************************************************************/
+/*
+ * load an fdpic binary into various bits of memory
+ */
+static int load_elf_fdpic_binary(struct linux_binprm *bprm, struct pt_regs *regs)
+{
+ struct elf_fdpic_params exec_params, interp_params;
+ struct elf_phdr *phdr;
+ unsigned long stack_size;
+ struct file *interpreter = NULL; /* to shut gcc up */
+ char *interpreter_name = NULL;
+ int executable_stack;
+ int retval, i;
+
+ memset(&exec_params, 0, sizeof(exec_params));
+ memset(&interp_params, 0, sizeof(interp_params));
+
+ exec_params.hdr = *(struct elfhdr *) bprm->buf;
+ exec_params.flags = ELF_FDPIC_FLAG_PRESENT | ELF_FDPIC_FLAG_EXECUTABLE;
+
+ /* check that this is a binary we know how to deal with */
+ retval = -ENOEXEC;
+ if (!is_elf_fdpic(&exec_params.hdr, bprm->file))
+ goto error;
+
+ /* read the program header table */
+ retval = elf_fdpic_fetch_phdrs(&exec_params, bprm->file);
+ if (retval < 0)
+ goto error;
+
+ /* scan for a program header that specifies an interpreter */
+ phdr = exec_params.phdrs;
+
+ for (i = 0; i < exec_params.hdr.e_phnum; i++, phdr++) {
+ switch (phdr->p_type) {
+ case PT_INTERP:
+ retval = -ENOMEM;
+ if (phdr->p_filesz > PATH_MAX)
+ goto error;
+ retval = -ENOENT;
+ if (phdr->p_filesz < 2)
+ goto error;
+
+ /* read the name of the interpreter into memory */
+ interpreter_name = (char *) kmalloc(phdr->p_filesz, GFP_KERNEL);
+ if (!interpreter_name)
+ goto error;
+
+ retval = kernel_read(bprm->file,
+ phdr->p_offset,
+ interpreter_name,
+ phdr->p_filesz);
+ if (retval < 0)
+ goto error;
+
+ retval = -ENOENT;
+ if (interpreter_name[phdr->p_filesz - 1] != '\0')
+ goto error;
+
+ kdebug("Using ELF interpreter %s", interpreter_name);
+
+ /* replace the program with the interpreter */
+ interpreter = open_exec(interpreter_name);
+ retval = PTR_ERR(interpreter);
+ if (IS_ERR(interpreter)) {
+ interpreter = NULL;
+ goto error;
+ }
+
+ retval = kernel_read(interpreter, 0, bprm->buf, BINPRM_BUF_SIZE);
+ if (retval < 0)
+ goto error;
+
+ interp_params.hdr = *((struct elfhdr *) bprm->buf);
+ break;
+
+ case PT_LOAD:
+#ifdef CONFIG_MMU
+ if (exec_params.load_addr == 0)
+ exec_params.load_addr = phdr->p_vaddr;
+#endif
+ break;
+ }
+
+ }
+
+ if (elf_check_const_displacement(&exec_params.hdr))
+ exec_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
+
+ /* perform insanity checks on the interpreter */
+ if (interpreter_name) {
+ retval = -ELIBBAD;
+ if (!is_elf_fdpic(&interp_params.hdr, interpreter))
+ goto error;
+
+ interp_params.flags = ELF_FDPIC_FLAG_PRESENT;
+
+ /* read the interpreter's program header table */
+ retval = elf_fdpic_fetch_phdrs(&interp_params, interpreter);
+ if (retval < 0)
+ goto error;
+ }
+
+ stack_size = exec_params.stack_size;
+ if (stack_size < interp_params.stack_size)
+ stack_size = interp_params.stack_size;
+
+ if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+ executable_stack = EXSTACK_ENABLE_X;
+ else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+ executable_stack = EXSTACK_DISABLE_X;
+ else if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+ executable_stack = EXSTACK_ENABLE_X;
+ else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+ executable_stack = EXSTACK_DISABLE_X;
+ else
+ executable_stack = EXSTACK_DEFAULT;
+
+ retval = -ENOEXEC;
+ if (stack_size == 0)
+ goto error;
+
+ if (elf_check_const_displacement(&interp_params.hdr))
+ interp_params.flags |= ELF_FDPIC_FLAG_CONSTDISP;
+
+ /* flush all traces of the currently running executable */
+ retval = flush_old_exec(bprm);
+ if (retval)
+ goto error;
+
+ /* there's now no turning back... the old userspace image is dead,
+ * defunct, deceased, etc. after this point we have to exit via
+ * error_kill */
+ set_personality(PER_LINUX_FDPIC);
+ set_binfmt(&elf_fdpic_format);
+
+ current->mm->start_code = 0;
+ current->mm->end_code = 0;
+ current->mm->start_stack = 0;
+ current->mm->start_data = 0;
+ current->mm->end_data = 0;
+ current->mm->context.exec_fdpic_loadmap = 0;
+ current->mm->context.interp_fdpic_loadmap = 0;
+
+ current->flags &= ~PF_FORKNOEXEC;
+
+#ifdef CONFIG_MMU
+ elf_fdpic_arch_lay_out_mm(&exec_params,
+ &interp_params,
+ &current->mm->start_stack,
+ &current->mm->start_brk);
+#endif
+
+ /* do this so that we can load the interpreter, if need be
+ * - we will change some of these later
+ */
+ set_mm_counter(current->mm, rss, 0);
+
+#ifdef CONFIG_MMU
+ retval = setup_arg_pages(bprm, current->mm->start_stack, executable_stack);
+ if (retval < 0) {
+ send_sig(SIGKILL, current, 0);
+ goto error_kill;
+ }
+#endif
+
+ /* load the executable and interpreter into memory */
+ retval = elf_fdpic_map_file(&exec_params, bprm->file, current->mm, "executable");
+ if (retval < 0)
+ goto error_kill;
+
+ if (interpreter_name) {
+ retval = elf_fdpic_map_file(&interp_params, interpreter,
+ current->mm, "interpreter");
+ if (retval < 0) {
+ printk(KERN_ERR "Unable to load interpreter\n");
+ goto error_kill;
+ }
+
+ allow_write_access(interpreter);
+ fput(interpreter);
+ interpreter = NULL;
+ }
+
+#ifdef CONFIG_MMU
+ if (!current->mm->start_brk)
+ current->mm->start_brk = current->mm->end_data;
+
+ current->mm->brk = current->mm->start_brk = PAGE_ALIGN(current->mm->start_brk);
+
+#else
+ /* create a stack and brk area big enough for everyone
+ * - the brk heap starts at the bottom and works up
+ * - the stack starts at the top and works down
+ */
+ stack_size = (stack_size + PAGE_SIZE - 1) & PAGE_MASK;
+ if (stack_size < PAGE_SIZE * 2)
+ stack_size = PAGE_SIZE * 2;
+
+ down_write(&current->mm->mmap_sem);
+ current->mm->start_brk = do_mmap(NULL,
+ 0,
+ stack_size,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_PRIVATE | MAP_ANON | MAP_GROWSDOWN,
+ 0);
+
+ if (IS_ERR((void *) current->mm->start_brk)) {
+ up_write(&current->mm->mmap_sem);
+ retval = current->mm->start_brk;
+ current->mm->start_brk = 0;
+ goto error_kill;
+ }
+
+ if (do_mremap(current->mm->start_brk,
+ stack_size,
+ ksize((char *) current->mm->start_brk),
+ 0, 0
+ ) == current->mm->start_brk
+ )
+ stack_size = ksize((char *) current->mm->start_brk);
+ up_write(&current->mm->mmap_sem);
+
+ current->mm->brk = current->mm->start_brk;
+ current->mm->context.end_brk = current->mm->start_brk;
+ current->mm->context.end_brk += (stack_size > PAGE_SIZE) ? (stack_size - PAGE_SIZE) : 0;
+ current->mm->start_stack = current->mm->start_brk + stack_size;
+#endif
+
+ compute_creds(bprm);
+ current->flags &= ~PF_FORKNOEXEC;
+ if (create_elf_fdpic_tables(bprm, current->mm, &exec_params, &interp_params) < 0)
+ goto error_kill;
+
+ kdebug("- start_code %lx", (long) current->mm->start_code);
+ kdebug("- end_code %lx", (long) current->mm->end_code);
+ kdebug("- start_data %lx", (long) current->mm->start_data);
+ kdebug("- end_data %lx", (long) current->mm->end_data);
+ kdebug("- start_brk %lx", (long) current->mm->start_brk);
+ kdebug("- brk %lx", (long) current->mm->brk);
+ kdebug("- start_stack %lx", (long) current->mm->start_stack);
+
+#ifdef ELF_FDPIC_PLAT_INIT
+ /*
+ * The ABI may specify that certain registers be set up in special
+ * ways (on i386 %edx is the address of a DT_FINI function, for
+ * example. This macro performs whatever initialization to
+ * the regs structure is required.
+ */
+ ELF_FDPIC_PLAT_INIT(regs,
+ exec_params.map_addr,
+ interp_params.map_addr,
+ interp_params.dynamic_addr ?: exec_params.dynamic_addr
+ );
+#endif
+
+ /* everything is now ready... get the userspace context ready to roll */
+ start_thread(regs,
+ interp_params.entry_addr ?: exec_params.entry_addr,
+ current->mm->start_stack);
+
+ if (unlikely(current->ptrace & PT_PTRACED)) {
+ if (current->ptrace & PT_TRACE_EXEC)
+ ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP);
+ else
+ send_sig(SIGTRAP, current, 0);
+ }
+
+ retval = 0;
+
+error:
+ if (interpreter) {
+ allow_write_access(interpreter);
+ fput(interpreter);
+ }
+ if (interpreter_name)
+ kfree(interpreter_name);
+ if (exec_params.phdrs)
+ kfree(exec_params.phdrs);
+ if (exec_params.loadmap)
+ kfree(exec_params.loadmap);
+ if (interp_params.phdrs)
+ kfree(interp_params.phdrs);
+ if (interp_params.loadmap)
+ kfree(interp_params.loadmap);
+ return retval;
+
+ /* unrecoverable error - kill the process */
+ error_kill:
+ send_sig(SIGSEGV, current, 0);
+ goto error;
+
+} /* end load_elf_fdpic_binary() */
+
+/*****************************************************************************/
+/*
+ * present useful information to the program
+ */
+static int create_elf_fdpic_tables(struct linux_binprm *bprm,
+ struct mm_struct *mm,
+ struct elf_fdpic_params *exec_params,
+ 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;
+ long hwcap;
+ int loop;
+
+ /* we're going to shovel a whole load of stuff onto the stack */
+#ifdef CONFIG_MMU
+ sp = bprm->p;
+#else
+ sp = mm->start_stack;
+
+ /* stack the program arguments and environment */
+ if (elf_fdpic_transfer_args_to_stack(bprm, &sp) < 0)
+ return -EFAULT;
+#endif
+
+ /* 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.
+ */
+ hwcap = ELF_HWCAP;
+ k_platform = ELF_PLATFORM;
+
+ if (k_platform) {
+ platform_len = strlen(k_platform) + 1;
+ sp -= platform_len;
+ if (__copy_to_user(u_platform, k_platform, platform_len) != 0)
+ return -EFAULT;
+ }
+
+ u_platform = (char *) sp;
+
+#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() */