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-rw-r--r--fs/binfmt_elf.c1677
1 files changed, 1677 insertions, 0 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
new file mode 100644
index 00000000000..76ec9d8939f
--- /dev/null
+++ b/fs/binfmt_elf.c
@@ -0,0 +1,1677 @@
+/*
+ * linux/fs/binfmt_elf.c
+ *
+ * These are the functions used to load ELF format executables as used
+ * on SVr4 machines. Information on the format may be found in the book
+ * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support
+ * Tools".
+ *
+ * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/a.out.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/ptrace.h>
+#include <linux/slab.h>
+#include <linux/shm.h>
+#include <linux/personality.h>
+#include <linux/elfcore.h>
+#include <linux/init.h>
+#include <linux/highuid.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/compiler.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/random.h>
+
+#include <asm/uaccess.h>
+#include <asm/param.h>
+#include <asm/page.h>
+
+#include <linux/elf.h>
+
+static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs);
+static int load_elf_library(struct file*);
+static unsigned long elf_map (struct file *, unsigned long, struct elf_phdr *, int, int);
+extern int dump_fpu (struct pt_regs *, elf_fpregset_t *);
+
+#ifndef elf_addr_t
+#define elf_addr_t unsigned long
+#endif
+
+/*
+ * If we don't support core dumping, then supply a NULL so we
+ * don't even try.
+ */
+#ifdef USE_ELF_CORE_DUMP
+static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file);
+#else
+#define elf_core_dump NULL
+#endif
+
+#if ELF_EXEC_PAGESIZE > PAGE_SIZE
+# define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
+#else
+# define ELF_MIN_ALIGN PAGE_SIZE
+#endif
+
+#ifndef ELF_CORE_EFLAGS
+#define ELF_CORE_EFLAGS 0
+#endif
+
+#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
+#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
+#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
+
+static struct linux_binfmt elf_format = {
+ .module = THIS_MODULE,
+ .load_binary = load_elf_binary,
+ .load_shlib = load_elf_library,
+ .core_dump = elf_core_dump,
+ .min_coredump = ELF_EXEC_PAGESIZE
+};
+
+#define BAD_ADDR(x) ((unsigned long)(x) > TASK_SIZE)
+
+static int set_brk(unsigned long start, unsigned long end)
+{
+ start = ELF_PAGEALIGN(start);
+ end = ELF_PAGEALIGN(end);
+ if (end > start) {
+ unsigned long addr;
+ down_write(&current->mm->mmap_sem);
+ addr = do_brk(start, end - start);
+ up_write(&current->mm->mmap_sem);
+ if (BAD_ADDR(addr))
+ return addr;
+ }
+ current->mm->start_brk = current->mm->brk = end;
+ return 0;
+}
+
+
+/* We need to explicitly zero any fractional pages
+ after the data section (i.e. bss). This would
+ contain the junk from the file that should not
+ be in memory */
+
+
+static int padzero(unsigned long elf_bss)
+{
+ unsigned long nbyte;
+
+ nbyte = ELF_PAGEOFFSET(elf_bss);
+ if (nbyte) {
+ nbyte = ELF_MIN_ALIGN - nbyte;
+ if (clear_user((void __user *) elf_bss, nbyte))
+ return -EFAULT;
+ }
+ return 0;
+}
+
+/* Let's use some macros to make this stack manipulation a litle clearer */
+#ifdef CONFIG_STACK_GROWSUP
+#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
+#define STACK_ROUND(sp, items) \
+ ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
+#define STACK_ALLOC(sp, len) ({ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; old_sp; })
+#else
+#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
+#define STACK_ROUND(sp, items) \
+ (((unsigned long) (sp - items)) &~ 15UL)
+#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
+#endif
+
+static int
+create_elf_tables(struct linux_binprm *bprm, struct elfhdr * exec,
+ int interp_aout, unsigned long load_addr,
+ unsigned long interp_load_addr)
+{
+ unsigned long p = bprm->p;
+ int argc = bprm->argc;
+ int envc = bprm->envc;
+ elf_addr_t __user *argv;
+ elf_addr_t __user *envp;
+ elf_addr_t __user *sp;
+ elf_addr_t __user *u_platform;
+ const char *k_platform = ELF_PLATFORM;
+ int items;
+ elf_addr_t *elf_info;
+ int ei_index = 0;
+ struct task_struct *tsk = current;
+
+ /*
+ * If this architecture has a platform capability string, copy it
+ * to userspace. In some cases (Sparc), this info is impossible
+ * for userspace to get any other way, in others (i386) it is
+ * merely difficult.
+ */
+
+ u_platform = NULL;
+ if (k_platform) {
+ size_t len = strlen(k_platform) + 1;
+
+ /*
+ * 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.
+ */
+
+ p = arch_align_stack(p);
+
+ u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
+ if (__copy_to_user(u_platform, k_platform, len))
+ return -EFAULT;
+ }
+
+ /* Create the ELF interpreter info */
+ elf_info = (elf_addr_t *) current->mm->saved_auxv;
+#define NEW_AUX_ENT(id, val) \
+ do { elf_info[ei_index++] = id; elf_info[ei_index++] = val; } while (0)
+
+#ifdef ARCH_DLINFO
+ /*
+ * ARCH_DLINFO must come first so PPC can do its special alignment of
+ * AUXV.
+ */
+ ARCH_DLINFO;
+#endif
+ NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
+ NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
+ NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
+ NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
+ NEW_AUX_ENT(AT_PHENT, sizeof (struct elf_phdr));
+ NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
+ NEW_AUX_ENT(AT_BASE, interp_load_addr);
+ NEW_AUX_ENT(AT_FLAGS, 0);
+ NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
+ NEW_AUX_ENT(AT_UID, (elf_addr_t) tsk->uid);
+ NEW_AUX_ENT(AT_EUID, (elf_addr_t) tsk->euid);
+ NEW_AUX_ENT(AT_GID, (elf_addr_t) tsk->gid);
+ NEW_AUX_ENT(AT_EGID, (elf_addr_t) tsk->egid);
+ NEW_AUX_ENT(AT_SECURE, (elf_addr_t) security_bprm_secureexec(bprm));
+ if (k_platform) {
+ NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform);
+ }
+ if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
+ NEW_AUX_ENT(AT_EXECFD, (elf_addr_t) bprm->interp_data);
+ }
+#undef NEW_AUX_ENT
+ /* AT_NULL is zero; clear the rest too */
+ memset(&elf_info[ei_index], 0,
+ sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
+
+ /* And advance past the AT_NULL entry. */
+ ei_index += 2;
+
+ sp = STACK_ADD(p, ei_index);
+
+ items = (argc + 1) + (envc + 1);
+ if (interp_aout) {
+ items += 3; /* a.out interpreters require argv & envp too */
+ } else {
+ items += 1; /* ELF interpreters only put argc on the stack */
+ }
+ bprm->p = STACK_ROUND(sp, items);
+
+ /* Point sp at the lowest address on the stack */
+#ifdef CONFIG_STACK_GROWSUP
+ sp = (elf_addr_t __user *)bprm->p - items - ei_index;
+ bprm->exec = (unsigned long) sp; /* XXX: PARISC HACK */
+#else
+ sp = (elf_addr_t __user *)bprm->p;
+#endif
+
+ /* Now, let's put argc (and argv, envp if appropriate) on the stack */
+ if (__put_user(argc, sp++))
+ return -EFAULT;
+ if (interp_aout) {
+ argv = sp + 2;
+ envp = argv + argc + 1;
+ __put_user((elf_addr_t)(unsigned long)argv, sp++);
+ __put_user((elf_addr_t)(unsigned long)envp, sp++);
+ } else {
+ argv = sp;
+ envp = argv + argc + 1;
+ }
+
+ /* Populate argv and envp */
+ p = current->mm->arg_start;
+ while (argc-- > 0) {
+ size_t len;
+ __put_user((elf_addr_t)p, argv++);
+ len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
+ if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
+ return 0;
+ p += len;
+ }
+ if (__put_user(0, argv))
+ return -EFAULT;
+ current->mm->arg_end = current->mm->env_start = p;
+ while (envc-- > 0) {
+ size_t len;
+ __put_user((elf_addr_t)p, envp++);
+ len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
+ if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
+ return 0;
+ p += len;
+ }
+ if (__put_user(0, envp))
+ return -EFAULT;
+ current->mm->env_end = p;
+
+ /* Put the elf_info on the stack in the right place. */
+ sp = (elf_addr_t __user *)envp + 1;
+ if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
+ return -EFAULT;
+ return 0;
+}
+
+#ifndef elf_map
+
+static unsigned long elf_map(struct file *filep, unsigned long addr,
+ struct elf_phdr *eppnt, int prot, int type)
+{
+ unsigned long map_addr;
+
+ down_write(&current->mm->mmap_sem);
+ map_addr = do_mmap(filep, ELF_PAGESTART(addr),
+ eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr), prot, type,
+ eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr));
+ up_write(&current->mm->mmap_sem);
+ return(map_addr);
+}
+
+#endif /* !elf_map */
+
+/* This is much more generalized than the library routine read function,
+ so we keep this separate. Technically the library read function
+ is only provided so that we can read a.out libraries that have
+ an ELF header */
+
+static unsigned long load_elf_interp(struct elfhdr * interp_elf_ex,
+ struct file * interpreter,
+ unsigned long *interp_load_addr)
+{
+ struct elf_phdr *elf_phdata;
+ struct elf_phdr *eppnt;
+ unsigned long load_addr = 0;
+ int load_addr_set = 0;
+ unsigned long last_bss = 0, elf_bss = 0;
+ unsigned long error = ~0UL;
+ int retval, i, size;
+
+ /* First of all, some simple consistency checks */
+ if (interp_elf_ex->e_type != ET_EXEC &&
+ interp_elf_ex->e_type != ET_DYN)
+ goto out;
+ if (!elf_check_arch(interp_elf_ex))
+ goto out;
+ if (!interpreter->f_op || !interpreter->f_op->mmap)
+ goto out;
+
+ /*
+ * If the size of this structure has changed, then punt, since
+ * we will be doing the wrong thing.
+ */
+ if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
+ goto out;
+ if (interp_elf_ex->e_phnum < 1 ||
+ interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
+ goto out;
+
+ /* Now read in all of the header information */
+
+ size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
+ if (size > ELF_MIN_ALIGN)
+ goto out;
+ elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL);
+ if (!elf_phdata)
+ goto out;
+
+ retval = kernel_read(interpreter,interp_elf_ex->e_phoff,(char *)elf_phdata,size);
+ error = -EIO;
+ if (retval != size) {
+ if (retval < 0)
+ error = retval;
+ goto out_close;
+ }
+
+ eppnt = elf_phdata;
+ for (i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) {
+ if (eppnt->p_type == PT_LOAD) {
+ int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
+ int elf_prot = 0;
+ unsigned long vaddr = 0;
+ unsigned long k, map_addr;
+
+ if (eppnt->p_flags & PF_R) elf_prot = PROT_READ;
+ if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
+ if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
+ vaddr = eppnt->p_vaddr;
+ if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
+ elf_type |= MAP_FIXED;
+
+ map_addr = elf_map(interpreter, load_addr + vaddr, eppnt, elf_prot, elf_type);
+ error = map_addr;
+ if (BAD_ADDR(map_addr))
+ goto out_close;
+
+ if (!load_addr_set && interp_elf_ex->e_type == ET_DYN) {
+ load_addr = map_addr - ELF_PAGESTART(vaddr);
+ load_addr_set = 1;
+ }
+
+ /*
+ * Check to see if the section's size will overflow the
+ * allowed task size. Note that p_filesz must always be
+ * <= p_memsize so it is only necessary to check p_memsz.
+ */
+ k = load_addr + eppnt->p_vaddr;
+ if (k > TASK_SIZE || eppnt->p_filesz > eppnt->p_memsz ||
+ eppnt->p_memsz > TASK_SIZE || TASK_SIZE - eppnt->p_memsz < k) {
+ error = -ENOMEM;
+ goto out_close;
+ }
+
+ /*
+ * Find the end of the file mapping for this phdr, and keep
+ * track of the largest address we see for this.
+ */
+ k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
+ if (k > elf_bss)
+ elf_bss = k;
+
+ /*
+ * Do the same thing for the memory mapping - between
+ * elf_bss and last_bss is the bss section.
+ */
+ k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
+ if (k > last_bss)
+ last_bss = k;
+ }
+ }
+
+ /*
+ * Now fill out the bss section. First pad the last page up
+ * to the page boundary, and then perform a mmap to make sure
+ * that there are zero-mapped pages up to and including the
+ * last bss page.
+ */
+ if (padzero(elf_bss)) {
+ error = -EFAULT;
+ goto out_close;
+ }
+
+ elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1); /* What we have mapped so far */
+
+ /* Map the last of the bss segment */
+ if (last_bss > elf_bss) {
+ down_write(&current->mm->mmap_sem);
+ error = do_brk(elf_bss, last_bss - elf_bss);
+ up_write(&current->mm->mmap_sem);
+ if (BAD_ADDR(error))
+ goto out_close;
+ }
+
+ *interp_load_addr = load_addr;
+ error = ((unsigned long) interp_elf_ex->e_entry) + load_addr;
+
+out_close:
+ kfree(elf_phdata);
+out:
+ return error;
+}
+
+static unsigned long load_aout_interp(struct exec * interp_ex,
+ struct file * interpreter)
+{
+ unsigned long text_data, elf_entry = ~0UL;
+ char __user * addr;
+ loff_t offset;
+
+ current->mm->end_code = interp_ex->a_text;
+ text_data = interp_ex->a_text + interp_ex->a_data;
+ current->mm->end_data = text_data;
+ current->mm->brk = interp_ex->a_bss + text_data;
+
+ switch (N_MAGIC(*interp_ex)) {
+ case OMAGIC:
+ offset = 32;
+ addr = (char __user *)0;
+ break;
+ case ZMAGIC:
+ case QMAGIC:
+ offset = N_TXTOFF(*interp_ex);
+ addr = (char __user *) N_TXTADDR(*interp_ex);
+ break;
+ default:
+ goto out;
+ }
+
+ down_write(&current->mm->mmap_sem);
+ do_brk(0, text_data);
+ up_write(&current->mm->mmap_sem);
+ if (!interpreter->f_op || !interpreter->f_op->read)
+ goto out;
+ if (interpreter->f_op->read(interpreter, addr, text_data, &offset) < 0)
+ goto out;
+ flush_icache_range((unsigned long)addr,
+ (unsigned long)addr + text_data);
+
+
+ down_write(&current->mm->mmap_sem);
+ do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
+ interp_ex->a_bss);
+ up_write(&current->mm->mmap_sem);
+ elf_entry = interp_ex->a_entry;
+
+out:
+ return elf_entry;
+}
+
+/*
+ * These are the functions used to load ELF style executables and shared
+ * libraries. There is no binary dependent code anywhere else.
+ */
+
+#define INTERPRETER_NONE 0
+#define INTERPRETER_AOUT 1
+#define INTERPRETER_ELF 2
+
+
+static unsigned long randomize_stack_top(unsigned long stack_top)
+{
+ unsigned int random_variable = 0;
+
+ if (current->flags & PF_RANDOMIZE)
+ random_variable = get_random_int() % (8*1024*1024);
+#ifdef CONFIG_STACK_GROWSUP
+ return PAGE_ALIGN(stack_top + random_variable);
+#else
+ return PAGE_ALIGN(stack_top - random_variable);
+#endif
+}
+
+static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs)
+{
+ struct file *interpreter = NULL; /* to shut gcc up */
+ unsigned long load_addr = 0, load_bias = 0;
+ int load_addr_set = 0;
+ char * elf_interpreter = NULL;
+ unsigned int interpreter_type = INTERPRETER_NONE;
+ unsigned char ibcs2_interpreter = 0;
+ unsigned long error;
+ struct elf_phdr * elf_ppnt, *elf_phdata;
+ unsigned long elf_bss, elf_brk;
+ int elf_exec_fileno;
+ int retval, i;
+ unsigned int size;
+ unsigned long elf_entry, interp_load_addr = 0;
+ unsigned long start_code, end_code, start_data, end_data;
+ unsigned long reloc_func_desc = 0;
+ char passed_fileno[6];
+ struct files_struct *files;
+ int have_pt_gnu_stack, executable_stack = EXSTACK_DEFAULT;
+ unsigned long def_flags = 0;
+ struct {
+ struct elfhdr elf_ex;
+ struct elfhdr interp_elf_ex;
+ struct exec interp_ex;
+ } *loc;
+
+ loc = kmalloc(sizeof(*loc), GFP_KERNEL);
+ if (!loc) {
+ retval = -ENOMEM;
+ goto out_ret;
+ }
+
+ /* Get the exec-header */
+ loc->elf_ex = *((struct elfhdr *) bprm->buf);
+
+ retval = -ENOEXEC;
+ /* First of all, some simple consistency checks */
+ if (memcmp(loc->elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+ goto out;
+
+ if (loc->elf_ex.e_type != ET_EXEC && loc->elf_ex.e_type != ET_DYN)
+ goto out;
+ if (!elf_check_arch(&loc->elf_ex))
+ goto out;
+ if (!bprm->file->f_op||!bprm->file->f_op->mmap)
+ goto out;
+
+ /* Now read in all of the header information */
+
+ if (loc->elf_ex.e_phentsize != sizeof(struct elf_phdr))
+ goto out;
+ if (loc->elf_ex.e_phnum < 1 ||
+ loc->elf_ex.e_phnum > 65536U / sizeof(struct elf_phdr))
+ goto out;
+ size = loc->elf_ex.e_phnum * sizeof(struct elf_phdr);
+ retval = -ENOMEM;
+ elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL);
+ if (!elf_phdata)
+ goto out;
+
+ retval = kernel_read(bprm->file, loc->elf_ex.e_phoff, (char *) elf_phdata, size);
+ if (retval != size) {
+ if (retval >= 0)
+ retval = -EIO;
+ goto out_free_ph;
+ }
+
+ files = current->files; /* Refcounted so ok */
+ retval = unshare_files();
+ if (retval < 0)
+ goto out_free_ph;
+ if (files == current->files) {
+ put_files_struct(files);
+ files = NULL;
+ }
+
+ /* exec will make our files private anyway, but for the a.out
+ loader stuff we need to do it earlier */
+
+ retval = get_unused_fd();
+ if (retval < 0)
+ goto out_free_fh;
+ get_file(bprm->file);
+ fd_install(elf_exec_fileno = retval, bprm->file);
+
+ elf_ppnt = elf_phdata;
+ elf_bss = 0;
+ elf_brk = 0;
+
+ start_code = ~0UL;
+ end_code = 0;
+ start_data = 0;
+ end_data = 0;
+
+ for (i = 0; i < loc->elf_ex.e_phnum; i++) {
+ if (elf_ppnt->p_type == PT_INTERP) {
+ /* This is the program interpreter used for
+ * shared libraries - for now assume that this
+ * is an a.out format binary
+ */
+
+ retval = -ENOEXEC;
+ if (elf_ppnt->p_filesz > PATH_MAX ||
+ elf_ppnt->p_filesz < 2)
+ goto out_free_file;
+
+ retval = -ENOMEM;
+ elf_interpreter = (char *) kmalloc(elf_ppnt->p_filesz,
+ GFP_KERNEL);
+ if (!elf_interpreter)
+ goto out_free_file;
+
+ retval = kernel_read(bprm->file, elf_ppnt->p_offset,
+ elf_interpreter,
+ elf_ppnt->p_filesz);
+ if (retval != elf_ppnt->p_filesz) {
+ if (retval >= 0)
+ retval = -EIO;
+ goto out_free_interp;
+ }
+ /* make sure path is NULL terminated */
+ retval = -ENOEXEC;
+ if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
+ goto out_free_interp;
+
+ /* If the program interpreter is one of these two,
+ * then assume an iBCS2 image. Otherwise assume
+ * a native linux image.
+ */
+ if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 ||
+ strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0)
+ ibcs2_interpreter = 1;
+
+ /*
+ * The early SET_PERSONALITY here is so that the lookup
+ * for the interpreter happens in the namespace of the
+ * to-be-execed image. SET_PERSONALITY can select an
+ * alternate root.
+ *
+ * However, SET_PERSONALITY is NOT allowed to switch
+ * this task into the new images's memory mapping
+ * policy - that is, TASK_SIZE must still evaluate to
+ * that which is appropriate to the execing application.
+ * This is because exit_mmap() needs to have TASK_SIZE
+ * evaluate to the size of the old image.
+ *
+ * So if (say) a 64-bit application is execing a 32-bit
+ * application it is the architecture's responsibility
+ * to defer changing the value of TASK_SIZE until the
+ * switch really is going to happen - do this in
+ * flush_thread(). - akpm
+ */
+ SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
+
+ interpreter = open_exec(elf_interpreter);
+ retval = PTR_ERR(interpreter);
+ if (IS_ERR(interpreter))
+ goto out_free_interp;
+ retval = kernel_read(interpreter, 0, bprm->buf, BINPRM_BUF_SIZE);
+ if (retval != BINPRM_BUF_SIZE) {
+ if (retval >= 0)
+ retval = -EIO;
+ goto out_free_dentry;
+ }
+
+ /* Get the exec headers */
+ loc->interp_ex = *((struct exec *) bprm->buf);
+ loc->interp_elf_ex = *((struct elfhdr *) bprm->buf);
+ break;
+ }
+ elf_ppnt++;
+ }
+
+ elf_ppnt = elf_phdata;
+ for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++)
+ if (elf_ppnt->p_type == PT_GNU_STACK) {
+ if (elf_ppnt->p_flags & PF_X)
+ executable_stack = EXSTACK_ENABLE_X;
+ else
+ executable_stack = EXSTACK_DISABLE_X;
+ break;
+ }
+ have_pt_gnu_stack = (i < loc->elf_ex.e_phnum);
+
+ /* Some simple consistency checks for the interpreter */
+ if (elf_interpreter) {
+ interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT;
+
+ /* Now figure out which format our binary is */
+ if ((N_MAGIC(loc->interp_ex) != OMAGIC) &&
+ (N_MAGIC(loc->interp_ex) != ZMAGIC) &&
+ (N_MAGIC(loc->interp_ex) != QMAGIC))
+ interpreter_type = INTERPRETER_ELF;
+
+ if (memcmp(loc->interp_elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+ interpreter_type &= ~INTERPRETER_ELF;
+
+ retval = -ELIBBAD;
+ if (!interpreter_type)
+ goto out_free_dentry;
+
+ /* Make sure only one type was selected */
+ if ((interpreter_type & INTERPRETER_ELF) &&
+ interpreter_type != INTERPRETER_ELF) {
+ // FIXME - ratelimit this before re-enabling
+ // printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n");
+ interpreter_type = INTERPRETER_ELF;
+ }
+ /* Verify the interpreter has a valid arch */
+ if ((interpreter_type == INTERPRETER_ELF) &&
+ !elf_check_arch(&loc->interp_elf_ex))
+ goto out_free_dentry;
+ } else {
+ /* Executables without an interpreter also need a personality */
+ SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
+ }
+
+ /* OK, we are done with that, now set up the arg stuff,
+ and then start this sucker up */
+
+ if ((!bprm->sh_bang) && (interpreter_type == INTERPRETER_AOUT)) {
+ char *passed_p = passed_fileno;
+ sprintf(passed_fileno, "%d", elf_exec_fileno);
+
+ if (elf_interpreter) {
+ retval = copy_strings_kernel(1, &passed_p, bprm);
+ if (retval)
+ goto out_free_dentry;
+ bprm->argc++;
+ }
+ }
+
+ /* Flush all traces of the currently running executable */
+ retval = flush_old_exec(bprm);
+ if (retval)
+ goto out_free_dentry;
+
+ /* Discard our unneeded old files struct */
+ if (files) {
+ steal_locks(files);
+ put_files_struct(files);
+ files = NULL;
+ }
+
+ /* OK, This is the point of no return */
+ current->mm->start_data = 0;
+ current->mm->end_data = 0;
+ current->mm->end_code = 0;
+ current->mm->mmap = NULL;
+ current->flags &= ~PF_FORKNOEXEC;
+ current->mm->def_flags = def_flags;
+
+ /* Do this immediately, since STACK_TOP as used in setup_arg_pages
+ may depend on the personality. */
+ SET_PERSONALITY(loc->elf_ex, ibcs2_interpreter);
+ if (elf_read_implies_exec(loc->elf_ex, executable_stack))
+ current->personality |= READ_IMPLIES_EXEC;
+
+ if ( !(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
+ current->flags |= PF_RANDOMIZE;
+ arch_pick_mmap_layout(current->mm);
+
+ /* 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);
+ current->mm->free_area_cache = current->mm->mmap_base;
+ retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
+ executable_stack);
+ if (retval < 0) {
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+
+#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
+ retval = arch_setup_additional_pages(bprm, executable_stack);
+ if (retval < 0) {
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
+
+ current->mm->start_stack = bprm->p;
+
+ /* Now we do a little grungy work by mmaping the ELF image into
+ the correct location in memory. At this point, we assume that
+ the image should be loaded at fixed address, not at a variable
+ address. */
+
+ for(i = 0, elf_ppnt = elf_phdata; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
+ int elf_prot = 0, elf_flags;
+ unsigned long k, vaddr;
+
+ if (elf_ppnt->p_type != PT_LOAD)
+ continue;
+
+ if (unlikely (elf_brk > elf_bss)) {
+ unsigned long nbyte;
+
+ /* There was a PT_LOAD segment with p_memsz > p_filesz
+ before this one. Map anonymous pages, if needed,
+ and clear the area. */
+ retval = set_brk (elf_bss + load_bias,
+ elf_brk + load_bias);
+ if (retval) {
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+ nbyte = ELF_PAGEOFFSET(elf_bss);
+ if (nbyte) {
+ nbyte = ELF_MIN_ALIGN - nbyte;
+ if (nbyte > elf_brk - elf_bss)
+ nbyte = elf_brk - elf_bss;
+ if (clear_user((void __user *)elf_bss +
+ load_bias, nbyte)) {
+ /*
+ * This bss-zeroing can fail if the ELF
+ * file specifies odd protections. So
+ * we don't check the return value
+ */
+ }
+ }
+ }
+
+ if (elf_ppnt->p_flags & PF_R) elf_prot |= PROT_READ;
+ if (elf_ppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
+ if (elf_ppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
+
+ elf_flags = MAP_PRIVATE|MAP_DENYWRITE|MAP_EXECUTABLE;
+
+ vaddr = elf_ppnt->p_vaddr;
+ if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
+ elf_flags |= MAP_FIXED;
+ } else if (loc->elf_ex.e_type == ET_DYN) {
+ /* Try and get dynamic programs out of the way of the default mmap
+ base, as well as whatever program they might try to exec. This
+ is because the brk will follow the loader, and is not movable. */
+ load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
+ }
+
+ error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt, elf_prot, elf_flags);
+ if (BAD_ADDR(error)) {
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+
+ if (!load_addr_set) {
+ load_addr_set = 1;
+ load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
+ if (loc->elf_ex.e_type == ET_DYN) {
+ load_bias += error -
+ ELF_PAGESTART(load_bias + vaddr);
+ load_addr += load_bias;
+ reloc_func_desc = load_bias;
+ }
+ }
+ k = elf_ppnt->p_vaddr;
+ if (k < start_code) start_code = k;
+ if (start_data < k) start_data = k;
+
+ /*
+ * Check to see if the section's size will overflow the
+ * allowed task size. Note that p_filesz must always be
+ * <= p_memsz so it is only necessary to check p_memsz.
+ */
+ if (k > TASK_SIZE || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
+ elf_ppnt->p_memsz > TASK_SIZE ||
+ TASK_SIZE - elf_ppnt->p_memsz < k) {
+ /* set_brk can never work. Avoid overflows. */
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
+
+ if (k > elf_bss)
+ elf_bss = k;
+ if ((elf_ppnt->p_flags & PF_X) && end_code < k)
+ end_code = k;
+ if (end_data < k)
+ end_data = k;
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
+ if (k > elf_brk)
+ elf_brk = k;
+ }
+
+ loc->elf_ex.e_entry += load_bias;
+ elf_bss += load_bias;
+ elf_brk += load_bias;
+ start_code += load_bias;
+ end_code += load_bias;
+ start_data += load_bias;
+ end_data += load_bias;
+
+ /* Calling set_brk effectively mmaps the pages that we need
+ * for the bss and break sections. We must do this before
+ * mapping in the interpreter, to make sure it doesn't wind
+ * up getting placed where the bss needs to go.
+ */
+ retval = set_brk(elf_bss, elf_brk);
+ if (retval) {
+ send_sig(SIGKILL, current, 0);
+ goto out_free_dentry;
+ }
+ if (padzero(elf_bss)) {
+ send_sig(SIGSEGV, current, 0);
+ retval = -EFAULT; /* Nobody gets to see this, but.. */
+ goto out_free_dentry;
+ }
+
+ if (elf_interpreter) {
+ if (interpreter_type == INTERPRETER_AOUT)
+ elf_entry = load_aout_interp(&loc->interp_ex,
+ interpreter);
+ else
+ elf_entry = load_elf_interp(&loc->interp_elf_ex,
+ interpreter,
+ &interp_load_addr);
+ if (BAD_ADDR(elf_entry)) {
+ printk(KERN_ERR "Unable to load interpreter %.128s\n",
+ elf_interpreter);
+ force_sig(SIGSEGV, current);
+ retval = -ENOEXEC; /* Nobody gets to see this, but.. */
+ goto out_free_dentry;
+ }
+ reloc_func_desc = interp_load_addr;
+
+ allow_write_access(interpreter);
+ fput(interpreter);
+ kfree(elf_interpreter);
+ } else {
+ elf_entry = loc->elf_ex.e_entry;
+ }
+
+ kfree(elf_phdata);
+
+ if (interpreter_type != INTERPRETER_AOUT)
+ sys_close(elf_exec_fileno);
+
+ set_binfmt(&elf_format);
+
+ compute_creds(bprm);
+ current->flags &= ~PF_FORKNOEXEC;
+ create_elf_tables(bprm, &loc->elf_ex, (interpreter_type == INTERPRETER_AOUT),
+ load_addr, interp_load_addr);
+ /* N.B. passed_fileno might not be initialized? */
+ if (interpreter_type == INTERPRETER_AOUT)
+ current->mm->arg_start += strlen(passed_fileno) + 1;
+ current->mm->end_code = end_code;
+ current->mm->start_code = start_code;
+ current->mm->start_data = start_data;
+ current->mm->end_data = end_data;
+ current->mm->start_stack = bprm->p;
+
+ if (current->personality & MMAP_PAGE_ZERO) {
+ /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
+ and some applications "depend" upon this behavior.
+ Since we do not have the power to recompile these, we
+ emulate the SVr4 behavior. Sigh. */
+ down_write(&current->mm->mmap_sem);
+ error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE, 0);
+ up_write(&current->mm->mmap_sem);
+ }
+
+#ifdef ELF_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. In addition, it may also specify (eg, PowerPC64 ELF)
+ * that the e_entry field is the address of the function descriptor
+ * for the startup routine, rather than the address of the startup
+ * routine itself. This macro performs whatever initialization to
+ * the regs structure is required as well as any relocations to the
+ * function descriptor entries when executing dynamically links apps.
+ */
+ ELF_PLAT_INIT(regs, reloc_func_desc);
+#endif
+
+ start_thread(regs, elf_entry, bprm->p);
+ 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;
+out:
+ kfree(loc);
+out_ret:
+ return retval;
+
+ /* error cleanup */
+out_free_dentry:
+ allow_write_access(interpreter);
+ if (interpreter)
+ fput(interpreter);
+out_free_interp:
+ if (elf_interpreter)
+ kfree(elf_interpreter);
+out_free_file:
+ sys_close(elf_exec_fileno);
+out_free_fh:
+ if (files) {
+ put_files_struct(current->files);
+ current->files = files;
+ }
+out_free_ph:
+ kfree(elf_phdata);
+ goto out;
+}
+
+/* This is really simpleminded and specialized - we are loading an
+ a.out library that is given an ELF header. */
+
+static int load_elf_library(struct file *file)
+{
+ struct elf_phdr *elf_phdata;
+ struct elf_phdr *eppnt;
+ unsigned long elf_bss, bss, len;
+ int retval, error, i, j;
+ struct elfhdr elf_ex;
+
+ error = -ENOEXEC;
+ retval = kernel_read(file, 0, (char *) &elf_ex, sizeof(elf_ex));
+ if (retval != sizeof(elf_ex))
+ goto out;
+
+ if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+ goto out;
+
+ /* First of all, some simple consistency checks */
+ if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
+ !elf_check_arch(&elf_ex) || !file->f_op || !file->f_op->mmap)
+ goto out;
+
+ /* Now read in all of the header information */
+
+ j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
+ /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
+
+ error = -ENOMEM;
+ elf_phdata = kmalloc(j, GFP_KERNEL);
+ if (!elf_phdata)
+ goto out;
+
+ eppnt = elf_phdata;
+ error = -ENOEXEC;
+ retval = kernel_read(file, elf_ex.e_phoff, (char *)eppnt, j);
+ if (retval != j)
+ goto out_free_ph;
+
+ for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
+ if ((eppnt + i)->p_type == PT_LOAD)
+ j++;
+ if (j != 1)
+ goto out_free_ph;
+
+ while (eppnt->p_type != PT_LOAD)
+ eppnt++;
+
+ /* Now use mmap to map the library into memory. */
+ down_write(&current->mm->mmap_sem);
+ error = do_mmap(file,
+ ELF_PAGESTART(eppnt->p_vaddr),
+ (eppnt->p_filesz +
+ ELF_PAGEOFFSET(eppnt->p_vaddr)),
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
+ (eppnt->p_offset -
+ ELF_PAGEOFFSET(eppnt->p_vaddr)));
+ up_write(&current->mm->mmap_sem);
+ if (error != ELF_PAGESTART(eppnt->p_vaddr))
+ goto out_free_ph;
+
+ elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
+ if (padzero(elf_bss)) {
+ error = -EFAULT;
+ goto out_free_ph;
+ }
+
+ len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + ELF_MIN_ALIGN - 1);
+ bss = eppnt->p_memsz + eppnt->p_vaddr;
+ if (bss > len) {
+ down_write(&current->mm->mmap_sem);
+ do_brk(len, bss - len);
+ up_write(&current->mm->mmap_sem);
+ }
+ error = 0;
+
+out_free_ph:
+ kfree(elf_phdata);
+out:
+ return error;
+}
+
+/*
+ * Note that some platforms still use traditional core dumps and not
+ * the ELF core dump. Each platform can select it as appropriate.
+ */
+#ifdef USE_ELF_CORE_DUMP
+
+/*
+ * ELF core dumper
+ *
+ * Modelled on fs/exec.c:aout_core_dump()
+ * Jeremy Fitzhardinge <jeremy@sw.oz.au>
+ */
+/*
+ * These are the only things you should do on a core-file: use only these
+ * functions to write out all the necessary info.
+ */
+static int dump_write(struct file *file, const void *addr, int nr)
+{
+ return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
+}
+
+static int dump_seek(struct file *file, off_t off)
+{
+ if (file->f_op->llseek) {
+ if (file->f_op->llseek(file, off, 0) != off)
+ return 0;
+ } else
+ file->f_pos = off;
+ return 1;
+}
+
+/*
+ * Decide whether a segment is worth dumping; default is yes to be
+ * sure (missing info is worse than too much; etc).
+ * Personally I'd include everything, and use the coredump limit...
+ *
+ * I think we should skip something. But I am not sure how. H.J.
+ */
+static int maydump(struct vm_area_struct *vma)
+{
+ /* Do not dump I/O mapped devices or special mappings */
+ if (vma->vm_flags & (VM_IO | VM_RESERVED))
+ return 0;
+
+ /* Dump shared memory only if mapped from an anonymous file. */
+ if (vma->vm_flags & VM_SHARED)
+ return vma->vm_file->f_dentry->d_inode->i_nlink == 0;
+
+ /* If it hasn't been written to, don't write it out */
+ if (!vma->anon_vma)
+ return 0;
+
+ return 1;
+}
+
+#define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
+
+/* An ELF note in memory */
+struct memelfnote
+{
+ const char *name;
+ int type;
+ unsigned int datasz;
+ void *data;
+};
+
+static int notesize(struct memelfnote *en)
+{
+ int sz;
+
+ sz = sizeof(struct elf_note);
+ sz += roundup(strlen(en->name) + 1, 4);
+ sz += roundup(en->datasz, 4);
+
+ return sz;
+}
+
+#define DUMP_WRITE(addr, nr) \
+ do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
+#define DUMP_SEEK(off) \
+ do { if (!dump_seek(file, (off))) return 0; } while(0)
+
+static int writenote(struct memelfnote *men, struct file *file)
+{
+ struct elf_note en;
+
+ en.n_namesz = strlen(men->name) + 1;
+ en.n_descsz = men->datasz;
+ en.n_type = men->type;
+
+ DUMP_WRITE(&en, sizeof(en));
+ DUMP_WRITE(men->name, en.n_namesz);
+ /* XXX - cast from long long to long to avoid need for libgcc.a */
+ DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
+ DUMP_WRITE(men->data, men->datasz);
+ DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
+
+ return 1;
+}
+#undef DUMP_WRITE
+#undef DUMP_SEEK
+
+#define DUMP_WRITE(addr, nr) \
+ if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
+ goto end_coredump;
+#define DUMP_SEEK(off) \
+ if (!dump_seek(file, (off))) \
+ goto end_coredump;
+
+static inline void fill_elf_header(struct elfhdr *elf, int segs)
+{
+ memcpy(elf->e_ident, ELFMAG, SELFMAG);
+ elf->e_ident[EI_CLASS] = ELF_CLASS;
+ elf->e_ident[EI_DATA] = ELF_DATA;
+ elf->e_ident[EI_VERSION] = EV_CURRENT;
+ elf->e_ident[EI_OSABI] = ELF_OSABI;
+ memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
+
+ elf->e_type = ET_CORE;
+ elf->e_machine = ELF_ARCH;
+ elf->e_version = EV_CURRENT;
+ elf->e_entry = 0;
+ elf->e_phoff = sizeof(struct elfhdr);
+ elf->e_shoff = 0;
+ elf->e_flags = ELF_CORE_EFLAGS;
+ elf->e_ehsize = sizeof(struct elfhdr);
+ elf->e_phentsize = sizeof(struct elf_phdr);
+ elf->e_phnum = segs;
+ elf->e_shentsize = 0;
+ elf->e_shnum = 0;
+ elf->e_shstrndx = 0;
+ return;
+}
+
+static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, off_t offset)
+{
+ phdr->p_type = PT_NOTE;
+ phdr->p_offset = offset;
+ phdr->p_vaddr = 0;
+ phdr->p_paddr = 0;
+ phdr->p_filesz = sz;
+ phdr->p_memsz = 0;
+ phdr->p_flags = 0;
+ phdr->p_align = 0;
+ return;
+}
+
+static void fill_note(struct memelfnote *note, const char *name, int type,
+ unsigned int sz, void *data)
+{
+ note->name = name;
+ note->type = type;
+ note->datasz = sz;
+ note->data = data;
+ return;
+}
+
+/*
+ * fill up all the fields in prstatus from the given task struct, except registers
+ * which need to be filled up separately.
+ */
+static void fill_prstatus(struct elf_prstatus *prstatus,
+ struct task_struct *p, long signr)
+{
+ prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
+ prstatus->pr_sigpend = p->pending.signal.sig[0];
+ prstatus->pr_sighold = p->blocked.sig[0];
+ prstatus->pr_pid = p->pid;
+ prstatus->pr_ppid = p->parent->pid;
+ prstatus->pr_pgrp = process_group(p);
+ prstatus->pr_sid = p->signal->session;
+ if (thread_group_leader(p)) {
+ /*
+ * This is the record for the group leader. Add in the
+ * cumulative times of previous dead threads. This total
+ * won't include the time of each live thread whose state
+ * is included in the core dump. The final total reported
+ * to our parent process when it calls wait4 will include
+ * those sums as well as the little bit more time it takes
+ * this and each other thread to finish dying after the
+ * core dump synchronization phase.
+ */
+ cputime_to_timeval(cputime_add(p->utime, p->signal->utime),
+ &prstatus->pr_utime);
+ cputime_to_timeval(cputime_add(p->stime, p->signal->stime),
+ &prstatus->pr_stime);
+ } else {
+ cputime_to_timeval(p->utime, &prstatus->pr_utime);
+ cputime_to_timeval(p->stime, &prstatus->pr_stime);
+ }
+ cputime_to_timeval(p->signal->cutime, &prstatus->pr_cutime);
+ cputime_to_timeval(p->signal->cstime, &prstatus->pr_cstime);
+}
+
+static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
+ struct mm_struct *mm)
+{
+ int i, len;
+
+ /* first copy the parameters from user space */
+ memset(psinfo, 0, sizeof(struct elf_prpsinfo));
+
+ len = mm->arg_end - mm->arg_start;
+ if (len >= ELF_PRARGSZ)
+ len = ELF_PRARGSZ-1;
+ if (copy_from_user(&psinfo->pr_psargs,
+ (const char __user *)mm->arg_start, len))
+ return -EFAULT;
+ for(i = 0; i < len; i++)
+ if (psinfo->pr_psargs[i] == 0)
+ psinfo->pr_psargs[i] = ' ';
+ psinfo->pr_psargs[len] = 0;
+
+ psinfo->pr_pid = p->pid;
+ psinfo->pr_ppid = p->parent->pid;
+ psinfo->pr_pgrp = process_group(p);
+ psinfo->pr_sid = p->signal->session;
+
+ i = p->state ? ffz(~p->state) + 1 : 0;
+ psinfo->pr_state = i;
+ psinfo->pr_sname = (i < 0 || i > 5) ? '.' : "RSDTZW"[i];
+ psinfo->pr_zomb = psinfo->pr_sname == 'Z';
+ psinfo->pr_nice = task_nice(p);
+ psinfo->pr_flag = p->flags;
+ SET_UID(psinfo->pr_uid, p->uid);
+ SET_GID(psinfo->pr_gid, p->gid);
+ strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
+
+ return 0;
+}
+
+/* Here is the structure in which status of each thread is captured. */
+struct elf_thread_status
+{
+ struct list_head list;
+ struct elf_prstatus prstatus; /* NT_PRSTATUS */
+ elf_fpregset_t fpu; /* NT_PRFPREG */
+ struct task_struct *thread;
+#ifdef ELF_CORE_COPY_XFPREGS
+ elf_fpxregset_t xfpu; /* NT_PRXFPREG */
+#endif
+ struct memelfnote notes[3];
+ int num_notes;
+};
+
+/*
+ * In order to add the specific thread information for the elf file format,
+ * we need to keep a linked list of every threads pr_status and then
+ * create a single section for them in the final core file.
+ */
+static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
+{
+ int sz = 0;
+ struct task_struct *p = t->thread;
+ t->num_notes = 0;
+
+ fill_prstatus(&t->prstatus, p, signr);
+ elf_core_copy_task_regs(p, &t->prstatus.pr_reg);
+
+ fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), &(t->prstatus));
+ t->num_notes++;
+ sz += notesize(&t->notes[0]);
+
+ if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL, &t->fpu))) {
+ fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), &(t->fpu));
+ t->num_notes++;
+ sz += notesize(&t->notes[1]);
+ }
+
+#ifdef ELF_CORE_COPY_XFPREGS
+ if (elf_core_copy_task_xfpregs(p, &t->xfpu)) {
+ fill_note(&t->notes[2], "LINUX", NT_PRXFPREG, sizeof(t->xfpu), &t->xfpu);
+ t->num_notes++;
+ sz += notesize(&t->notes[2]);
+ }
+#endif
+ return sz;
+}
+
+/*
+ * Actual dumper
+ *
+ * This is a two-pass process; first we find the offsets of the bits,
+ * and then they are actually written out. If we run out of core limit
+ * we just truncate.
+ */
+static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file)
+{
+#define NUM_NOTES 6
+ int has_dumped = 0;
+ mm_segment_t fs;
+ int segs;
+ size_t size = 0;
+ int i;
+ struct vm_area_struct *vma;
+ struct elfhdr *elf = NULL;
+ off_t offset = 0, dataoff;
+ unsigned long limit = current->signal->rlim[RLIMIT_CORE].rlim_cur;
+ int numnote;
+ struct memelfnote *notes = NULL;
+ struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
+ struct elf_prpsinfo *psinfo = NULL; /* NT_PRPSINFO */
+ struct task_struct *g, *p;
+ LIST_HEAD(thread_list);
+ struct list_head *t;
+ elf_fpregset_t *fpu = NULL;
+#ifdef ELF_CORE_COPY_XFPREGS
+ elf_fpxregset_t *xfpu = NULL;
+#endif
+ int thread_status_size = 0;
+ elf_addr_t *auxv;
+
+ /*
+ * We no longer stop all VM operations.
+ *
+ * This is because those proceses that could possibly change map_count or
+ * the mmap / vma pages are now blocked in do_exit on current finishing
+ * this core dump.
+ *
+ * Only ptrace can touch these memory addresses, but it doesn't change
+ * the map_count or the pages allocated. So no possibility of crashing
+ * exists while dumping the mm->vm_next areas to the core file.
+ */
+
+ /* alloc memory for large data structures: too large to be on stack */
+ elf = kmalloc(sizeof(*elf), GFP_KERNEL);
+ if (!elf)
+ goto cleanup;
+ prstatus = kmalloc(sizeof(*prstatus), GFP_KERNEL);
+ if (!prstatus)
+ goto cleanup;
+ psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
+ if (!psinfo)
+ goto cleanup;
+ notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote), GFP_KERNEL);
+ if (!notes)
+ goto cleanup;
+ fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
+ if (!fpu)
+ goto cleanup;
+#ifdef ELF_CORE_COPY_XFPREGS
+ xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
+ if (!xfpu)
+ goto cleanup;
+#endif
+
+ if (signr) {
+ struct elf_thread_status *tmp;
+ read_lock(&tasklist_lock);
+ do_each_thread(g,p)
+ if (current->mm == p->mm && current != p) {
+ tmp = kmalloc(sizeof(*tmp), GFP_ATOMIC);
+ if (!tmp) {
+ read_unlock(&tasklist_lock);
+ goto cleanup;
+ }
+ memset(tmp, 0, sizeof(*tmp));
+ INIT_LIST_HEAD(&tmp->list);
+ tmp->thread = p;
+ list_add(&tmp->list, &thread_list);
+ }
+ while_each_thread(g,p);
+ read_unlock(&tasklist_lock);
+ list_for_each(t, &thread_list) {
+ struct elf_thread_status *tmp;
+ int sz;
+
+ tmp = list_entry(t, struct elf_thread_status, list);
+ sz = elf_dump_thread_status(signr, tmp);
+ thread_status_size += sz;
+ }
+ }
+ /* now collect the dump for the current */
+ memset(prstatus, 0, sizeof(*prstatus));
+ fill_prstatus(prstatus, current, signr);
+ elf_core_copy_regs(&prstatus->pr_reg, regs);
+
+ segs = current->mm->map_count;
+#ifdef ELF_CORE_EXTRA_PHDRS
+ segs += ELF_CORE_EXTRA_PHDRS;
+#endif
+
+ /* Set up header */
+ fill_elf_header(elf, segs+1); /* including notes section */
+
+ has_dumped = 1;
+ current->flags |= PF_DUMPCORE;
+
+ /*
+ * Set up the notes in similar form to SVR4 core dumps made
+ * with info from their /proc.
+ */
+
+ fill_note(notes +0, "CORE", NT_PRSTATUS, sizeof(*prstatus), prstatus);
+
+ fill_psinfo(psinfo, current->group_leader, current->mm);
+ fill_note(notes +1, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
+
+ fill_note(notes +2, "CORE", NT_TASKSTRUCT, sizeof(*current), current);
+
+ numnote = 3;
+
+ auxv = (elf_addr_t *) current->mm->saved_auxv;
+
+ i = 0;
+ do
+ i += 2;
+ while (auxv[i - 2] != AT_NULL);
+ fill_note(&notes[numnote++], "CORE", NT_AUXV,
+ i * sizeof (elf_addr_t), auxv);
+
+ /* Try to dump the FPU. */
+ if ((prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs, fpu)))
+ fill_note(notes + numnote++,
+ "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
+#ifdef ELF_CORE_COPY_XFPREGS
+ if (elf_core_copy_task_xfpregs(current, xfpu))
+ fill_note(notes + numnote++,
+ "LINUX", NT_PRXFPREG, sizeof(*xfpu), xfpu);
+#endif
+
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ DUMP_WRITE(elf, sizeof(*elf));
+ offset += sizeof(*elf); /* Elf header */
+ offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
+
+ /* Write notes phdr entry */
+ {
+ struct elf_phdr phdr;
+ int sz = 0;
+
+ for (i = 0; i < numnote; i++)
+ sz += notesize(notes + i);
+
+ sz += thread_status_size;
+
+ fill_elf_note_phdr(&phdr, sz, offset);
+ offset += sz;
+ DUMP_WRITE(&phdr, sizeof(phdr));
+ }
+
+ /* Page-align dumped data */
+ dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
+
+ /* Write program headers for segments dump */
+ for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
+ struct elf_phdr phdr;
+ size_t sz;
+
+ sz = vma->vm_end - vma->vm_start;
+
+ phdr.p_type = PT_LOAD;
+ phdr.p_offset = offset;
+ phdr.p_vaddr = vma->vm_start;
+ phdr.p_paddr = 0;
+ phdr.p_filesz = maydump(vma) ? sz : 0;
+ phdr.p_memsz = sz;
+ offset += phdr.p_filesz;
+ phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
+ if (vma->vm_flags & VM_WRITE) phdr.p_flags |= PF_W;
+ if (vma->vm_flags & VM_EXEC) phdr.p_flags |= PF_X;
+ phdr.p_align = ELF_EXEC_PAGESIZE;
+
+ DUMP_WRITE(&phdr, sizeof(phdr));
+ }
+
+#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
+ ELF_CORE_WRITE_EXTRA_PHDRS;
+#endif
+
+ /* write out the notes section */
+ for (i = 0; i < numnote; i++)
+ if (!writenote(notes + i, file))
+ goto end_coredump;
+
+ /* write out the thread status notes section */
+ list_for_each(t, &thread_list) {
+ struct elf_thread_status *tmp = list_entry(t, struct elf_thread_status, list);
+ for (i = 0; i < tmp->num_notes; i++)
+ if (!writenote(&tmp->notes[i], file))
+ goto end_coredump;
+ }
+
+ DUMP_SEEK(dataoff);
+
+ for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
+ unsigned long addr;
+
+ if (!maydump(vma))
+ continue;
+
+ for (addr = vma->vm_start;
+ addr < vma->vm_end;
+ addr += PAGE_SIZE) {
+ struct page* page;
+ struct vm_area_struct *vma;
+
+ if (get_user_pages(current, current->mm, addr, 1, 0, 1,
+ &page, &vma) <= 0) {
+ DUMP_SEEK (file->f_pos + PAGE_SIZE);
+ } else {
+ if (page == ZERO_PAGE(addr)) {
+ DUMP_SEEK (file->f_pos + PAGE_SIZE);
+ } else {
+ void *kaddr;
+ flush_cache_page(vma, addr, page_to_pfn(page));
+ kaddr = kmap(page);
+ if ((size += PAGE_SIZE) > limit ||
+ !dump_write(file, kaddr,
+ PAGE_SIZE)) {
+ kunmap(page);
+ page_cache_release(page);
+ goto end_coredump;
+ }
+ kunmap(page);
+ }
+ page_cache_release(page);
+ }
+ }
+ }
+
+#ifdef ELF_CORE_WRITE_EXTRA_DATA
+ ELF_CORE_WRITE_EXTRA_DATA;
+#endif
+
+ if ((off_t) file->f_pos != offset) {
+ /* Sanity check */
+ printk("elf_core_dump: file->f_pos (%ld) != offset (%ld)\n",
+ (off_t) file->f_pos, offset);
+ }
+
+end_coredump:
+ set_fs(fs);
+
+cleanup:
+ while(!list_empty(&thread_list)) {
+ struct list_head *tmp = thread_list.next;
+ list_del(tmp);
+ kfree(list_entry(tmp, struct elf_thread_status, list));
+ }
+
+ kfree(elf);
+ kfree(prstatus);
+ kfree(psinfo);
+ kfree(notes);
+ kfree(fpu);
+#ifdef ELF_CORE_COPY_XFPREGS
+ kfree(xfpu);
+#endif
+ return has_dumped;
+#undef NUM_NOTES
+}
+
+#endif /* USE_ELF_CORE_DUMP */
+
+static int __init init_elf_binfmt(void)
+{
+ return register_binfmt(&elf_format);
+}
+
+static void __exit exit_elf_binfmt(void)
+{
+ /* Remove the COFF and ELF loaders. */
+ unregister_binfmt(&elf_format);
+}
+
+core_initcall(init_elf_binfmt);
+module_exit(exit_elf_binfmt);
+MODULE_LICENSE("GPL");