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![Suresh Siddha](/assets/img/avatar_default.png)
Fixes a local DOS on Intel systems that lead to an endless recursive fault. AMD machines don't seem to be affected. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1685 lines
46 KiB
C
1685 lines
46 KiB
C
/*
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* linux/fs/binfmt_elf.c
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*
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* These are the functions used to load ELF format executables as used
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* on SVr4 machines. Information on the format may be found in the book
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* "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support
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* Tools".
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*
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* Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/fs.h>
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#include <linux/stat.h>
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#include <linux/time.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/a.out.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/ptrace.h>
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#include <linux/slab.h>
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#include <linux/shm.h>
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#include <linux/personality.h>
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#include <linux/elfcore.h>
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#include <linux/init.h>
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#include <linux/highuid.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/compiler.h>
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#include <linux/highmem.h>
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#include <linux/pagemap.h>
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#include <linux/security.h>
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#include <linux/syscalls.h>
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#include <linux/random.h>
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#include <asm/uaccess.h>
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#include <asm/param.h>
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#include <asm/page.h>
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#include <linux/elf.h>
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static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs);
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static int load_elf_library(struct file*);
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static unsigned long elf_map (struct file *, unsigned long, struct elf_phdr *, int, int);
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extern int dump_fpu (struct pt_regs *, elf_fpregset_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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/*
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* If we don't support core dumping, then supply a NULL so we
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* don't even try.
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*/
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#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
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static int elf_core_dump(long signr, struct pt_regs * regs, struct file * file);
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#else
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#define elf_core_dump NULL
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#endif
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#if ELF_EXEC_PAGESIZE > PAGE_SIZE
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# define ELF_MIN_ALIGN ELF_EXEC_PAGESIZE
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#else
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# define ELF_MIN_ALIGN PAGE_SIZE
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#endif
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#ifndef ELF_CORE_EFLAGS
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#define ELF_CORE_EFLAGS 0
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#endif
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#define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
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#define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
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#define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
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static struct linux_binfmt elf_format = {
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.module = THIS_MODULE,
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.load_binary = load_elf_binary,
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.load_shlib = load_elf_library,
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.core_dump = elf_core_dump,
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.min_coredump = ELF_EXEC_PAGESIZE
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};
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#define BAD_ADDR(x) ((unsigned long)(x) > TASK_SIZE)
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static int set_brk(unsigned long start, unsigned long end)
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{
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start = ELF_PAGEALIGN(start);
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end = ELF_PAGEALIGN(end);
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if (end > start) {
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unsigned long addr;
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down_write(¤t->mm->mmap_sem);
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addr = do_brk(start, end - start);
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up_write(¤t->mm->mmap_sem);
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if (BAD_ADDR(addr))
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return addr;
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}
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current->mm->start_brk = current->mm->brk = end;
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return 0;
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}
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/* We need to explicitly zero any fractional pages
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after the data section (i.e. bss). This would
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contain the junk from the file that should not
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be in memory */
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static int padzero(unsigned long elf_bss)
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{
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unsigned long nbyte;
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nbyte = ELF_PAGEOFFSET(elf_bss);
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if (nbyte) {
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nbyte = ELF_MIN_ALIGN - nbyte;
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if (clear_user((void __user *) elf_bss, nbyte))
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return -EFAULT;
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}
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return 0;
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}
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/* Let's use some macros to make this stack manipulation a litle clearer */
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#ifdef CONFIG_STACK_GROWSUP
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#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
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#define STACK_ROUND(sp, items) \
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((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
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#define STACK_ALLOC(sp, len) ({ elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; old_sp; })
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#else
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#define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
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#define STACK_ROUND(sp, items) \
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(((unsigned long) (sp - items)) &~ 15UL)
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#define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
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#endif
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static int
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create_elf_tables(struct linux_binprm *bprm, struct elfhdr * exec,
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int interp_aout, unsigned long load_addr,
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unsigned long interp_load_addr)
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{
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unsigned long p = bprm->p;
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int argc = bprm->argc;
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int envc = bprm->envc;
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elf_addr_t __user *argv;
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elf_addr_t __user *envp;
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elf_addr_t __user *sp;
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elf_addr_t __user *u_platform;
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const char *k_platform = ELF_PLATFORM;
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int items;
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elf_addr_t *elf_info;
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int ei_index = 0;
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struct task_struct *tsk = current;
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/*
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* If this architecture has a platform capability string, copy it
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* to userspace. In some cases (Sparc), this info is impossible
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* for userspace to get any other way, in others (i386) it is
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* merely difficult.
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*/
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u_platform = NULL;
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if (k_platform) {
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size_t len = strlen(k_platform) + 1;
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/*
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* In some cases (e.g. Hyper-Threading), we want to avoid L1
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* evictions by the processes running on the same package. One
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* thing we can do is to shuffle the initial stack for them.
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*/
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p = arch_align_stack(p);
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u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
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if (__copy_to_user(u_platform, k_platform, len))
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return -EFAULT;
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}
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/* Create the ELF interpreter info */
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elf_info = (elf_addr_t *) current->mm->saved_auxv;
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#define NEW_AUX_ENT(id, val) \
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do { elf_info[ei_index++] = id; elf_info[ei_index++] = val; } while (0)
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#ifdef ARCH_DLINFO
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/*
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* ARCH_DLINFO must come first so PPC can do its special alignment of
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* AUXV.
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*/
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ARCH_DLINFO;
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#endif
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NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
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NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
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NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
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NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
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NEW_AUX_ENT(AT_PHENT, sizeof (struct elf_phdr));
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NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
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NEW_AUX_ENT(AT_BASE, interp_load_addr);
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NEW_AUX_ENT(AT_FLAGS, 0);
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NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
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NEW_AUX_ENT(AT_UID, (elf_addr_t) tsk->uid);
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NEW_AUX_ENT(AT_EUID, (elf_addr_t) tsk->euid);
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NEW_AUX_ENT(AT_GID, (elf_addr_t) tsk->gid);
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NEW_AUX_ENT(AT_EGID, (elf_addr_t) tsk->egid);
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NEW_AUX_ENT(AT_SECURE, (elf_addr_t) security_bprm_secureexec(bprm));
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if (k_platform) {
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NEW_AUX_ENT(AT_PLATFORM, (elf_addr_t)(unsigned long)u_platform);
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}
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if (bprm->interp_flags & BINPRM_FLAGS_EXECFD) {
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NEW_AUX_ENT(AT_EXECFD, (elf_addr_t) bprm->interp_data);
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}
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#undef NEW_AUX_ENT
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/* AT_NULL is zero; clear the rest too */
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memset(&elf_info[ei_index], 0,
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sizeof current->mm->saved_auxv - ei_index * sizeof elf_info[0]);
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/* And advance past the AT_NULL entry. */
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ei_index += 2;
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sp = STACK_ADD(p, ei_index);
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items = (argc + 1) + (envc + 1);
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if (interp_aout) {
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items += 3; /* a.out interpreters require argv & envp too */
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} else {
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items += 1; /* ELF interpreters only put argc on the stack */
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}
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bprm->p = STACK_ROUND(sp, items);
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/* Point sp at the lowest address on the stack */
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#ifdef CONFIG_STACK_GROWSUP
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sp = (elf_addr_t __user *)bprm->p - items - ei_index;
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bprm->exec = (unsigned long) sp; /* XXX: PARISC HACK */
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#else
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sp = (elf_addr_t __user *)bprm->p;
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#endif
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/* Now, let's put argc (and argv, envp if appropriate) on the stack */
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if (__put_user(argc, sp++))
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return -EFAULT;
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if (interp_aout) {
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argv = sp + 2;
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envp = argv + argc + 1;
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__put_user((elf_addr_t)(unsigned long)argv, sp++);
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__put_user((elf_addr_t)(unsigned long)envp, sp++);
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} else {
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argv = sp;
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envp = argv + argc + 1;
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}
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/* Populate argv and envp */
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p = current->mm->arg_end = current->mm->arg_start;
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while (argc-- > 0) {
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size_t len;
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__put_user((elf_addr_t)p, argv++);
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len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
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if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
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return 0;
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p += len;
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}
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if (__put_user(0, argv))
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return -EFAULT;
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current->mm->arg_end = current->mm->env_start = p;
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while (envc-- > 0) {
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size_t len;
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__put_user((elf_addr_t)p, envp++);
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len = strnlen_user((void __user *)p, PAGE_SIZE*MAX_ARG_PAGES);
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if (!len || len > PAGE_SIZE*MAX_ARG_PAGES)
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return 0;
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p += len;
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}
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if (__put_user(0, envp))
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return -EFAULT;
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current->mm->env_end = p;
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/* Put the elf_info on the stack in the right place. */
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sp = (elf_addr_t __user *)envp + 1;
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if (copy_to_user(sp, elf_info, ei_index * sizeof(elf_addr_t)))
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return -EFAULT;
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return 0;
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}
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#ifndef elf_map
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static unsigned long elf_map(struct file *filep, unsigned long addr,
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struct elf_phdr *eppnt, int prot, int type)
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{
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unsigned long map_addr;
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unsigned long pageoffset = ELF_PAGEOFFSET(eppnt->p_vaddr);
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down_write(¤t->mm->mmap_sem);
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/* mmap() will return -EINVAL if given a zero size, but a
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* segment with zero filesize is perfectly valid */
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if (eppnt->p_filesz + pageoffset)
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map_addr = do_mmap(filep, ELF_PAGESTART(addr),
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eppnt->p_filesz + pageoffset, prot, type,
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eppnt->p_offset - pageoffset);
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else
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map_addr = ELF_PAGESTART(addr);
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up_write(¤t->mm->mmap_sem);
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return(map_addr);
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}
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#endif /* !elf_map */
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/* This is much more generalized than the library routine read function,
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so we keep this separate. Technically the library read function
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is only provided so that we can read a.out libraries that have
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an ELF header */
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static unsigned long load_elf_interp(struct elfhdr * interp_elf_ex,
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struct file * interpreter,
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unsigned long *interp_load_addr)
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{
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struct elf_phdr *elf_phdata;
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struct elf_phdr *eppnt;
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unsigned long load_addr = 0;
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int load_addr_set = 0;
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unsigned long last_bss = 0, elf_bss = 0;
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unsigned long error = ~0UL;
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int retval, i, size;
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/* First of all, some simple consistency checks */
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if (interp_elf_ex->e_type != ET_EXEC &&
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interp_elf_ex->e_type != ET_DYN)
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goto out;
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if (!elf_check_arch(interp_elf_ex))
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goto out;
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if (!interpreter->f_op || !interpreter->f_op->mmap)
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goto out;
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/*
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* If the size of this structure has changed, then punt, since
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* we will be doing the wrong thing.
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*/
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if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
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goto out;
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if (interp_elf_ex->e_phnum < 1 ||
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interp_elf_ex->e_phnum > 65536U / sizeof(struct elf_phdr))
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goto out;
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/* Now read in all of the header information */
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size = sizeof(struct elf_phdr) * interp_elf_ex->e_phnum;
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if (size > ELF_MIN_ALIGN)
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goto out;
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elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL);
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if (!elf_phdata)
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goto out;
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retval = kernel_read(interpreter,interp_elf_ex->e_phoff,(char *)elf_phdata,size);
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error = -EIO;
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if (retval != size) {
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if (retval < 0)
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error = retval;
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goto out_close;
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}
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eppnt = elf_phdata;
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for (i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) {
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if (eppnt->p_type == PT_LOAD) {
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int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
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int elf_prot = 0;
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unsigned long vaddr = 0;
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unsigned long k, map_addr;
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|
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if (eppnt->p_flags & PF_R) elf_prot = PROT_READ;
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if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
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if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
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vaddr = eppnt->p_vaddr;
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if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
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elf_type |= MAP_FIXED;
|
|
|
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map_addr = elf_map(interpreter, load_addr + vaddr, eppnt, elf_prot, elf_type);
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error = map_addr;
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if (BAD_ADDR(map_addr))
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goto out_close;
|
|
|
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if (!load_addr_set && interp_elf_ex->e_type == ET_DYN) {
|
|
load_addr = map_addr - ELF_PAGESTART(vaddr);
|
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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.
|
|
*/
|
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k = load_addr + eppnt->p_vaddr;
|
|
if (k > TASK_SIZE || eppnt->p_filesz > eppnt->p_memsz ||
|
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eppnt->p_memsz > TASK_SIZE || TASK_SIZE - eppnt->p_memsz < k) {
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|
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)
|
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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(¤t->mm->mmap_sem);
|
|
error = do_brk(elf_bss, last_bss - elf_bss);
|
|
up_write(¤t->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(¤t->mm->mmap_sem);
|
|
do_brk(0, text_data);
|
|
up_write(¤t->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(¤t->mm->mmap_sem);
|
|
do_brk(ELF_PAGESTART(text_data + ELF_MIN_ALIGN - 1),
|
|
interp_ex->a_bss);
|
|
up_write(¤t->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 = 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 */
|
|
current->mm->free_area_cache = current->mm->mmap_base;
|
|
current->mm->cached_hole_size = 0;
|
|
retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
|
|
executable_stack);
|
|
if (retval < 0) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out_free_dentry;
|
|
}
|
|
|
|
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 (likely(elf_bss != elf_brk) && unlikely(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;
|
|
if (BAD_ADDR(elf_entry)) {
|
|
send_sig(SIGSEGV, current, 0);
|
|
retval = -ENOEXEC; /* Nobody gets to see this, but.. */
|
|
goto out_free_dentry;
|
|
}
|
|
}
|
|
|
|
kfree(elf_phdata);
|
|
|
|
if (interpreter_type != INTERPRETER_AOUT)
|
|
sys_close(elf_exec_fileno);
|
|
|
|
set_binfmt(&elf_format);
|
|
|
|
#ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
|
|
retval = arch_setup_additional_pages(bprm, executable_stack);
|
|
if (retval < 0) {
|
|
send_sig(SIGKILL, current, 0);
|
|
goto out;
|
|
}
|
|
#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
|
|
|
|
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(¤t->mm->mmap_sem);
|
|
error = do_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
|
|
MAP_FIXED | MAP_PRIVATE, 0);
|
|
up_write(¤t->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:
|
|
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(¤t->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(¤t->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(¤t->mm->mmap_sem);
|
|
do_brk(len, bss - len);
|
|
up_write(¤t->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.
|
|
*/
|
|
#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
|
|
|
|
/*
|
|
* 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, loff_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 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 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)
|
|
{
|
|
unsigned 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);
|
|
|
|
numnote = 2;
|
|
|
|
auxv = (elf_addr_t *) current->mm->saved_auxv;
|
|
|
|
i = 0;
|
|
do
|
|
i += 2;
|
|
while (auxv[i - 2] != AT_NULL);
|
|
fill_note(¬es[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(KERN_WARNING "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");
|