Beispiel #1
0
static int aout32_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
{
	mm_segment_t fs;
	int has_dumped = 0;
	unsigned long dump_start, dump_size;
	struct user dump;
#       define START_DATA(u)    (u.u_tsize)
#       define START_STACK(u)   ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))

	fs = get_fs();
	set_fs(KERNEL_DS);
	has_dumped = 1;
	current->flags |= PF_DUMPCORE;
       	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
	dump.signal = signr;
	aout_dump_thread(regs, &dump);

/* If the size of the dump file exceeds the rlimit, then see what would happen
   if we wrote the stack, but not the data area.  */
	if (dump.u_dsize + dump.u_ssize > limit)
		dump.u_dsize = 0;

/* Make sure we have enough room to write the stack and data areas. */
	if (dump.u_ssize > limit)
		dump.u_ssize = 0;

/* make sure we actually have a data and stack area to dump */
	set_fs(USER_DS);
	if (!access_ok(VERIFY_READ, (void __user *) START_DATA(dump), dump.u_dsize))
		dump.u_dsize = 0;
	if (!access_ok(VERIFY_READ, (void __user *) START_STACK(dump), dump.u_ssize))
		dump.u_ssize = 0;

	set_fs(KERNEL_DS);
/* struct user */
	DUMP_WRITE(&dump,sizeof(dump));
/* now we start writing out the user space info */
	set_fs(USER_DS);
/* Dump the data area */
	if (dump.u_dsize != 0) {
		dump_start = START_DATA(dump);
		dump_size = dump.u_dsize;
		DUMP_WRITE(dump_start,dump_size);
	}
/* Now prepare to dump the stack area */
	if (dump.u_ssize != 0) {
		dump_start = START_STACK(dump);
		dump_size = dump.u_ssize;
		DUMP_WRITE(dump_start,dump_size);
	}
/* Finally dump the task struct.  Not be used by gdb, but could be useful */
	set_fs(KERNEL_DS);
	DUMP_WRITE(current,sizeof(*current));
end_coredump:
	set_fs(fs);
	return has_dumped;
}
Beispiel #2
0
static int writenote(struct memelfnote *men, struct file *file)
{
	struct elf_note en;

	en.n_namesz = strlen(men->name);
	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;
}
Beispiel #3
0
/*
 * 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)
{
	int has_dumped = 0;
	mm_segment_t fs;
	int segs;
	size_t size = 0;
	int i;
	struct vm_area_struct *vma;
	struct elfhdr elf;
	off_t offset = 0, dataoff;
	unsigned long limit = current->rlim[RLIMIT_CORE].rlim_cur;
	int numnote = 4;
	struct memelfnote notes[4];
	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
	elf_fpregset_t fpu;		/* NT_PRFPREG */
	struct elf_prpsinfo psinfo;	/* NT_PRPSINFO */

	/* first copy the parameters from user space */
	memset(&psinfo, 0, sizeof(psinfo));
	{
		unsigned int i, len;

		len = current->mm->arg_end - current->mm->arg_start;
		if (len >= ELF_PRARGSZ)
			len = ELF_PRARGSZ-1;
		copy_from_user(&psinfo.pr_psargs,
			      (const char *)current->mm->arg_start, len);
		for(i = 0; i < len; i++)
			if (psinfo.pr_psargs[i] == 0)
				psinfo.pr_psargs[i] = ' ';
		psinfo.pr_psargs[len] = 0;

	}

	memset(&prstatus, 0, sizeof(prstatus));
	/*
	 * This transfers the registers from regs into the standard
	 * coredump arrangement, whatever that is.
	 */
#ifdef ELF_CORE_COPY_REGS
	ELF_CORE_COPY_REGS(prstatus.pr_reg, regs)
#else
	if (sizeof(elf_gregset_t) != sizeof(struct pt_regs))
	{
		printk("sizeof(elf_gregset_t) (%ld) != sizeof(struct pt_regs) (%ld)\n",
			(long)sizeof(elf_gregset_t), (long)sizeof(struct pt_regs));
	}
	else
		*(struct pt_regs *)&prstatus.pr_reg = *regs;
#endif

	/* now stop all vm operations */
	down_write(&current->mm->mmap_sem);
	segs = current->mm->map_count;

#ifdef DEBUG
	printk("elf_core_dump: %d segs %lu limit\n", segs, limit);
#endif

	/* Set up header */
	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;
	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(elf);
	elf.e_shoff = 0;
#ifdef ELF_CORE_EFLAGS
	elf.e_flags = ELF_CORE_EFLAGS;
#else
	elf.e_flags = 0;
#endif
	elf.e_ehsize = sizeof(elf);
	elf.e_phentsize = sizeof(struct elf_phdr);
	elf.e_phnum = segs+1;		/* Include notes */
	elf.e_shentsize = 0;
	elf.e_shnum = 0;
	elf.e_shstrndx = 0;

	fs = get_fs();
	set_fs(KERNEL_DS);

	has_dumped = 1;
	current->flags |= PF_DUMPCORE;

	DUMP_WRITE(&elf, sizeof(elf));
	offset += sizeof(elf);				/* Elf header */
	offset += (segs+1) * sizeof(struct elf_phdr);	/* Program headers */

	/*
	 * Set up the notes in similar form to SVR4 core dumps made
	 * with info from their /proc.
	 */

	notes[0].name = "CORE";
	notes[0].type = NT_PRSTATUS;
	notes[0].datasz = sizeof(prstatus);
	notes[0].data = &prstatus;
	prstatus.pr_info.si_signo = prstatus.pr_cursig = signr;
	prstatus.pr_sigpend = current->pending.signal.sig[0];
	prstatus.pr_sighold = current->blocked.sig[0];
	psinfo.pr_pid = prstatus.pr_pid = current->pid;
	psinfo.pr_ppid = prstatus.pr_ppid = current->p_pptr->pid;
	psinfo.pr_pgrp = prstatus.pr_pgrp = current->pgrp;
	psinfo.pr_sid = prstatus.pr_sid = current->session;
	prstatus.pr_utime.tv_sec = CT_TO_SECS(current->times.tms_utime);
	prstatus.pr_utime.tv_usec = CT_TO_USECS(current->times.tms_utime);
	prstatus.pr_stime.tv_sec = CT_TO_SECS(current->times.tms_stime);
	prstatus.pr_stime.tv_usec = CT_TO_USECS(current->times.tms_stime);
	prstatus.pr_cutime.tv_sec = CT_TO_SECS(current->times.tms_cutime);
	prstatus.pr_cutime.tv_usec = CT_TO_USECS(current->times.tms_cutime);
	prstatus.pr_cstime.tv_sec = CT_TO_SECS(current->times.tms_cstime);
	prstatus.pr_cstime.tv_usec = CT_TO_USECS(current->times.tms_cstime);

#ifdef DEBUG
	dump_regs("Passed in regs", (elf_greg_t *)regs);
	dump_regs("prstatus regs", (elf_greg_t *)&prstatus.pr_reg);
#endif

	notes[1].name = "CORE";
	notes[1].type = NT_PRPSINFO;
	notes[1].datasz = sizeof(psinfo);
	notes[1].data = &psinfo;
	i = current->state ? ffz(~current->state) + 1 : 0;
	psinfo.pr_state = i;
	psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i];
	psinfo.pr_zomb = psinfo.pr_sname == 'Z';
	psinfo.pr_nice = task_nice(current);
	psinfo.pr_flag = current->flags;
	psinfo.pr_uid = NEW_TO_OLD_UID(current->uid);
	psinfo.pr_gid = NEW_TO_OLD_GID(current->gid);
	strncpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname));

	notes[2].name = "CORE";
	notes[2].type = NT_TASKSTRUCT;
	notes[2].datasz = sizeof(*current);
	notes[2].data = current;

	/* Try to dump the FPU. */
	prstatus.pr_fpvalid = dump_fpu (regs, &fpu);
	if (!prstatus.pr_fpvalid)
	{
		numnote--;
	}
	else
	{
		notes[3].name = "CORE";
		notes[3].type = NT_PRFPREG;
		notes[3].datasz = sizeof(fpu);
		notes[3].data = &fpu;
	}
	
	/* Write notes phdr entry */
	{
		struct elf_phdr phdr;
		int sz = 0;

		for(i = 0; i < numnote; i++)
			sz += notesize(&notes[i]);

		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;

		offset += phdr.p_filesz;
		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));
	}

	for(i = 0; i < numnote; i++)
		if (!writenote(&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;

#ifdef DEBUG
		printk("elf_core_dump: writing %08lx-%08lx\n", vma->vm_start, vma->vm_end);
#endif

		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);
					kaddr = kmap(page);
					DUMP_WRITE(kaddr, PAGE_SIZE);
					flush_page_to_ram(page);
					kunmap(page);
				}
				put_page(page);
			}
		}
	}

	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);
	up_write(&current->mm->mmap_sem);
	return has_dumped;
}
static unsigned long get_kcore_size(int *num_vma, size_t *elf_buflen)
{
	unsigned long size;
#ifndef NO_MM
	unsigned long try;
	struct vm_struct *m;
#endif

	*num_vma = 0;
	size = ((size_t)high_memory - PAGE_OFFSET + PAGE_SIZE);
#ifdef NO_MM
	/* vmlist is not available then */
	*elf_buflen = PAGE_SIZE;
	return size;
#else
	if (!vmlist) {
		*elf_buflen = PAGE_SIZE;
		return (size);
	}

	for (m=vmlist; m; m=m->next) {
		try = (unsigned long)m->addr + m->size;
		if (try > size)
			size = try;
		*num_vma = *num_vma + 1;
	}
	*elf_buflen =	sizeof(struct elfhdr) + 
			(*num_vma + 2)*sizeof(struct elf_phdr) + 
			3 * (sizeof(struct elf_note) + 4) +
			sizeof(struct elf_prstatus) +
			sizeof(struct elf_prpsinfo) +
			sizeof(struct task_struct);
	*elf_buflen = PAGE_ALIGN(*elf_buflen);
	return (size - PAGE_OFFSET + *elf_buflen);
#endif
}


/*****************************************************************************/
/*
 * determine size of ELF note
 */
static int notesize(struct memelfnote *en)
{
	int sz;

	sz = sizeof(struct elf_note);
	sz += roundup(strlen(en->name), 4);
	sz += roundup(en->datasz, 4);

	return sz;
} /* end notesize() */

/*****************************************************************************/
/*
 * store a note in the header buffer
 */
static char *storenote(struct memelfnote *men, char *bufp)
{
	struct elf_note en;

#define DUMP_WRITE(addr,nr) do { memcpy(bufp,addr,nr); bufp += nr; } while(0)

	en.n_namesz = strlen(men->name);
	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 */
	bufp = (char*) roundup((unsigned long)bufp,4);
	DUMP_WRITE(men->data, men->datasz);
	bufp = (char*) roundup((unsigned long)bufp,4);

#undef DUMP_WRITE

	return bufp;
} /* end storenote() */

/*
 * store an ELF coredump header in the supplied buffer
 * num_vma is the number of elements in vmlist
 */
static void elf_kcore_store_hdr(char *bufp, int num_vma, int dataoff)
{
	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
	struct elf_prpsinfo prpsinfo;	/* NT_PRPSINFO */
	struct elf_phdr *nhdr, *phdr;
	struct elfhdr *elf;
	struct memelfnote notes[3];
	off_t offset = 0;
#ifndef NO_MM
	struct vm_struct *m;
#endif

	/* setup ELF header */
	elf = (struct elfhdr *) bufp;
	bufp += sizeof(struct elfhdr);
	offset += sizeof(struct elfhdr);
	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;
	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	= 0;
	elf->e_ehsize	= sizeof(struct elfhdr);
	elf->e_phentsize= sizeof(struct elf_phdr);
	elf->e_phnum	= 2 + num_vma;
	elf->e_shentsize= 0;
	elf->e_shnum	= 0;
	elf->e_shstrndx	= 0;

	/* setup ELF PT_NOTE program header */
	nhdr = (struct elf_phdr *) bufp;
	bufp += sizeof(struct elf_phdr);
	offset += sizeof(struct elf_phdr);
	nhdr->p_type	= PT_NOTE;
	nhdr->p_offset	= 0;
	nhdr->p_vaddr	= 0;
	nhdr->p_paddr	= 0;
	nhdr->p_filesz	= 0;
	nhdr->p_memsz	= 0;
	nhdr->p_flags	= 0;
	nhdr->p_align	= 0;

	/* setup ELF PT_LOAD program header for the 
	 * virtual range 0xc0000000 -> high_memory */
	phdr = (struct elf_phdr *) bufp;
	bufp += sizeof(struct elf_phdr);
	offset += sizeof(struct elf_phdr);
	phdr->p_type	= PT_LOAD;
	phdr->p_flags	= PF_R|PF_W|PF_X;
	phdr->p_offset	= dataoff;
	phdr->p_vaddr	= PAGE_OFFSET;
	phdr->p_paddr	= __pa(PAGE_OFFSET);
	phdr->p_filesz	= phdr->p_memsz = ((unsigned long)high_memory - PAGE_OFFSET);
	phdr->p_align	= PAGE_SIZE;

#ifndef NO_MM
	/* setup ELF PT_LOAD program header for every vmalloc'd area */
	for (m=vmlist; m; m=m->next) {
		if (m->flags & VM_IOREMAP) /* don't dump ioremap'd stuff! (TA) */
			continue;

		phdr = (struct elf_phdr *) bufp;
		bufp += sizeof(struct elf_phdr);
		offset += sizeof(struct elf_phdr);

		phdr->p_type	= PT_LOAD;
		phdr->p_flags	= PF_R|PF_W|PF_X;
		phdr->p_offset	= (size_t)m->addr - PAGE_OFFSET + dataoff;
		phdr->p_vaddr	= (size_t)m->addr;
		phdr->p_paddr	= __pa(m->addr);
		phdr->p_filesz	= phdr->p_memsz	= m->size;
		phdr->p_align	= PAGE_SIZE;
	}
#endif /* NO_MM */

	/*
	 * Set up the notes in similar form to SVR4 core dumps made
	 * with info from their /proc.
	 */
	nhdr->p_offset	= offset;

	/* set up the process status */
	notes[0].name = "CORE";
	notes[0].type = NT_PRSTATUS;
	notes[0].datasz = sizeof(struct elf_prstatus);
	notes[0].data = &prstatus;

	memset(&prstatus, 0, sizeof(struct elf_prstatus));

	nhdr->p_filesz += notesize(&notes[0]);
	bufp = storenote(&notes[0], bufp);

	/* set up the process info */
	notes[1].name	= "CORE";
	notes[1].type	= NT_PRPSINFO;
	notes[1].datasz	= sizeof(struct elf_prpsinfo);
	notes[1].data	= &prpsinfo;

	memset(&prpsinfo, 0, sizeof(struct elf_prpsinfo));
	prpsinfo.pr_state	= 0;
	prpsinfo.pr_sname	= 'R';
	prpsinfo.pr_zomb	= 0;

	strcpy(prpsinfo.pr_fname, "vmlinux");
	strncpy(prpsinfo.pr_psargs, saved_command_line, ELF_PRARGSZ);

	nhdr->p_filesz += notesize(&notes[1]);
	bufp = storenote(&notes[1], bufp);

	/* set up the task structure */
	notes[2].name	= "CORE";
	notes[2].type	= NT_TASKSTRUCT;
	notes[2].datasz	= sizeof(struct task_struct);
	notes[2].data	= current;

	nhdr->p_filesz += notesize(&notes[2]);
	bufp = storenote(&notes[2], bufp);

} /* end elf_kcore_store_hdr() */

/*****************************************************************************/
/*
 * read from the ELF header and then kernel memory
 */
static ssize_t read_kcore(struct file *file, char *buffer, size_t buflen, loff_t *fpos)
{
	ssize_t acc = 0;
	unsigned long size, tsz;
	size_t elf_buflen;
	int num_vma;
	unsigned long start;

#ifdef NO_MM
	proc_root_kcore->size = size = get_kcore_size(&num_vma, &elf_buflen);
#else
	read_lock(&vmlist_lock);
	proc_root_kcore->size = size = get_kcore_size(&num_vma, &elf_buflen);
	if (buflen == 0 || (unsigned long long)*fpos >= size) {
		read_unlock(&vmlist_lock);
		return 0;
	}
#endif /* NO_MM */

	/* trim buflen to not go beyond EOF */
	if (buflen > size - *fpos)
		buflen = size - *fpos;

	/* construct an ELF core header if we'll need some of it */
	if (*fpos < elf_buflen) {
		char * elf_buf;

		tsz = elf_buflen - *fpos;
		if (buflen < tsz)
			tsz = buflen;
		elf_buf = kmalloc(elf_buflen, GFP_ATOMIC);
		if (!elf_buf) {
#ifndef NO_MM
			read_unlock(&vmlist_lock);
#endif
			return -ENOMEM;
		}
		memset(elf_buf, 0, elf_buflen);
		elf_kcore_store_hdr(elf_buf, num_vma, elf_buflen);
#ifndef NO_MM
		read_unlock(&vmlist_lock);
#endif
		if (copy_to_user(buffer, elf_buf + *fpos, tsz)) {
			kfree(elf_buf);
			return -EFAULT;
		}
		kfree(elf_buf);
		buflen -= tsz;
		*fpos += tsz;
		buffer += tsz;
		acc += tsz;

		/* leave now if filled buffer already */
		if (buflen == 0)
			return acc;
	} else {
#ifndef NO_MM
		read_unlock(&vmlist_lock);
#endif
	}

	/* where page 0 not mapped, write zeros into buffer */
#if defined (__i386__) || defined (__mc68000__) || defined(__x86_64__)
	if (*fpos < PAGE_SIZE + elf_buflen) {
		/* work out how much to clear */
		tsz = PAGE_SIZE + elf_buflen - *fpos;
		if (buflen < tsz)
			tsz = buflen;

		/* write zeros to buffer */
		if (clear_user(buffer, tsz))
			return -EFAULT;
		buflen -= tsz;
		*fpos += tsz;
		buffer += tsz;
		acc += tsz;

		/* leave now if filled buffer already */
		if (buflen == 0)
			return tsz;
	}
#endif
	
	/*
	 * Fill the remainder of the buffer from kernel VM space.
	 * We said in the ELF header that the data which starts
	 * at 'elf_buflen' is virtual address PAGE_OFFSET. --rmk
	 */
	start = PAGE_OFFSET + (*fpos - elf_buflen);
	if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
		tsz = buflen;
	while (buflen) {
		int err = 0; 
	
		if ((start > PAGE_OFFSET) && (start < (unsigned long)high_memory)) {
			if (kern_addr_valid(start)) {
				err = copy_to_user(buffer, (char *)start, tsz);
			} else {
				err = clear_user(buffer, tsz);
			}
		} else {
#ifndef NO_MM
			char * elf_buf;
			struct vm_struct *m;
			unsigned long curstart = start;
			unsigned long cursize = tsz;

			elf_buf = kmalloc(tsz, GFP_KERNEL);
			if (!elf_buf)
				return -ENOMEM;
			memset(elf_buf, 0, tsz);

			read_lock(&vmlist_lock);
			for (m=vmlist; m && cursize; m=m->next) {
				unsigned long vmstart;
				unsigned long vmsize;
				unsigned long msize = m->size - PAGE_SIZE;

				if (((unsigned long)m->addr + msize) < 
								curstart)
					continue;
				if ((unsigned long)m->addr > (curstart + 
								cursize))
					break;
				vmstart = (curstart < (unsigned long)m->addr ? 
					(unsigned long)m->addr : curstart);
				if (((unsigned long)m->addr + msize) > 
							(curstart + cursize))
					vmsize = curstart + cursize - vmstart;
				else
					vmsize = (unsigned long)m->addr + 
							msize - vmstart;
				curstart = vmstart + vmsize;
				cursize -= vmsize;
				/* don't dump ioremap'd stuff! (TA) */
				if (m->flags & VM_IOREMAP)
					continue;
				memcpy(elf_buf + (vmstart - start),
					(char *)vmstart, vmsize);
			}
			read_unlock(&vmlist_lock);
			err = copy_to_user(buffer, elf_buf, tsz); 
				kfree(elf_buf);
#endif /* NO_MM */
			}
		if (err)
					return -EFAULT;
		buflen -= tsz;
		*fpos += tsz;
		buffer += tsz;
		acc += tsz;
		start += tsz;
		tsz = (buflen > PAGE_SIZE ? PAGE_SIZE : buflen);
	}

	return acc;
}
Beispiel #5
0
/* 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 irix_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit)
{
	int has_dumped = 0;
	mm_segment_t fs;
	int segs;
	int i;
	size_t size;
	struct vm_area_struct *vma;
	struct elfhdr elf;
	off_t offset = 0, dataoff;
	int numnote = 3;
	struct memelfnote notes[3];
	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
	elf_fpregset_t fpu;		/* NT_PRFPREG */
	struct elf_prpsinfo psinfo;	/* NT_PRPSINFO */

	/* Count what's needed to dump, up to the limit of coredump size. */
	segs = 0;
	size = 0;
	for (vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
		if (maydump(vma))
		{
			int sz = vma->vm_end-vma->vm_start;

			if (size+sz >= limit)
				break;
			else
				size += sz;
		}

		segs++;
	}
	pr_debug("irix_core_dump: %d segs taking %d bytes\n", segs, size);

	/* Set up header. */
	memcpy(elf.e_ident, ELFMAG, SELFMAG);
	elf.e_ident[EI_CLASS] = ELFCLASS32;
	elf.e_ident[EI_DATA] = ELFDATA2LSB;
	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(elf);
	elf.e_shoff = 0;
	elf.e_flags = 0;
	elf.e_ehsize = sizeof(elf);
	elf.e_phentsize = sizeof(struct elf_phdr);
	elf.e_phnum = segs+1;		/* Include notes. */
	elf.e_shentsize = 0;
	elf.e_shnum = 0;
	elf.e_shstrndx = 0;

	fs = get_fs();
	set_fs(KERNEL_DS);

	has_dumped = 1;
	current->flags |= PF_DUMPCORE;

	DUMP_WRITE(&elf, sizeof(elf));
	offset += sizeof(elf);				/* Elf header. */
	offset += (segs+1) * sizeof(struct elf_phdr);	/* Program headers. */

	/* Set up the notes in similar form to SVR4 core dumps made
	 * with info from their /proc.
	 */
	memset(&psinfo, 0, sizeof(psinfo));
	memset(&prstatus, 0, sizeof(prstatus));

	notes[0].name = "CORE";
	notes[0].type = NT_PRSTATUS;
	notes[0].datasz = sizeof(prstatus);
	notes[0].data = &prstatus;
	prstatus.pr_info.si_signo = prstatus.pr_cursig = signr;
	prstatus.pr_sigpend = current->pending.signal.sig[0];
	prstatus.pr_sighold = current->blocked.sig[0];
	psinfo.pr_pid = prstatus.pr_pid = task_pid_vnr(current);
	psinfo.pr_ppid = prstatus.pr_ppid = task_pid_vnr(current->parent);
	psinfo.pr_pgrp = prstatus.pr_pgrp = task_pgrp_vnr(current);
	psinfo.pr_sid = prstatus.pr_sid = task_session_vnr(current);
	if (thread_group_leader(current)) {
		/*
		 * 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.
		 */
		jiffies_to_timeval(current->utime + current->signal->utime,
		                   &prstatus.pr_utime);
		jiffies_to_timeval(current->stime + current->signal->stime,
		                   &prstatus.pr_stime);
	} else {
		jiffies_to_timeval(current->utime, &prstatus.pr_utime);
		jiffies_to_timeval(current->stime, &prstatus.pr_stime);
	}
	jiffies_to_timeval(current->signal->cutime, &prstatus.pr_cutime);
	jiffies_to_timeval(current->signal->cstime, &prstatus.pr_cstime);

	if (sizeof(elf_gregset_t) != sizeof(struct pt_regs)) {
		printk("sizeof(elf_gregset_t) (%d) != sizeof(struct pt_regs) "
		       "(%d)\n", sizeof(elf_gregset_t), sizeof(struct pt_regs));
	} else {
		*(struct pt_regs *)&prstatus.pr_reg = *regs;
	}

	notes[1].name = "CORE";
	notes[1].type = NT_PRPSINFO;
	notes[1].datasz = sizeof(psinfo);
	notes[1].data = &psinfo;
	i = current->state ? ffz(~current->state) + 1 : 0;
	psinfo.pr_state = i;
	psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i];
	psinfo.pr_zomb = psinfo.pr_sname == 'Z';
	psinfo.pr_nice = task_nice(current);
	psinfo.pr_flag = current->flags;
	psinfo.pr_uid = current->uid;
	psinfo.pr_gid = current->gid;
	{
		int i, len;

		set_fs(fs);

		len = current->mm->arg_end - current->mm->arg_start;
		len = len >= ELF_PRARGSZ ? ELF_PRARGSZ : len;
		(void *) copy_from_user(&psinfo.pr_psargs,
			       (const char __user *)current->mm->arg_start, len);
		for (i = 0; i < len; i++)
			if (psinfo.pr_psargs[i] == 0)
				psinfo.pr_psargs[i] = ' ';
		psinfo.pr_psargs[len] = 0;

		set_fs(KERNEL_DS);
	}
	strlcpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname));

	/* Try to dump the FPU. */
	prstatus.pr_fpvalid = dump_fpu(regs, &fpu);
	if (!prstatus.pr_fpvalid) {
		numnote--;
	} else {
		notes[2].name = "CORE";
		notes[2].type = NT_PRFPREG;
		notes[2].datasz = sizeof(fpu);
		notes[2].data = &fpu;
	}

	/* Write notes phdr entry. */
	{
		struct elf_phdr phdr;
		int sz = 0;

		for (i = 0; i < numnote; i++)
			sz += notesize(&notes[i]);

		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;

		offset += phdr.p_filesz;
		DUMP_WRITE(&phdr, sizeof(phdr));
	}

	/* Page-align dumped data. */
	dataoff = offset = roundup(offset, PAGE_SIZE);

	/* Write program headers for segments dump. */
	for (vma = current->mm->mmap, i = 0;
		i < segs && vma != NULL; vma = vma->vm_next) {
		struct elf_phdr phdr;
		size_t sz;

		i++;

		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 = PAGE_SIZE;

		DUMP_WRITE(&phdr, sizeof(phdr));
	}

	for (i = 0; i < numnote; i++)
		if (!writenote(&notes[i], file))
			goto end_coredump;

	set_fs(fs);

	DUMP_SEEK(dataoff);

	for (i = 0, vma = current->mm->mmap;
	    i < segs && vma != NULL;
	    vma = vma->vm_next) {
		unsigned long addr = vma->vm_start;
		unsigned long len = vma->vm_end - vma->vm_start;

		if (!maydump(vma))
			continue;
		i++;
		pr_debug("elf_core_dump: writing %08lx %lx\n", addr, len);
		DUMP_WRITE((void __user *)addr, len);
	}

	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);
	return has_dumped;
}
Beispiel #6
0
static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file)
{
	mm_segment_t fs;
	int has_dumped = 0;
	unsigned long dump_start, dump_size;
	struct user dump;
#if defined(__alpha__)
#       define START_DATA(u)	(u.start_data)
#elif defined(__arm__)
#	define START_DATA(u)	((u.u_tsize << PAGE_SHIFT) + u.start_code)
#elif defined(__sparc__)
#       define START_DATA(u)    (u.u_tsize)
#elif defined(__i386__) || defined(__mc68000__) || defined(__arch_um__)
#       define START_DATA(u)	(u.u_tsize << PAGE_SHIFT)
#endif
#ifdef __sparc__
#       define START_STACK(u)   ((regs->u_regs[UREG_FP]) & ~(PAGE_SIZE - 1))
#else
#       define START_STACK(u)   (u.start_stack)
#endif

	fs = get_fs();
	set_fs(KERNEL_DS);
	has_dumped = 1;
	current->flags |= PF_DUMPCORE;
       	strncpy(dump.u_comm, current->comm, sizeof(current->comm));
#ifndef __sparc__
	dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
#endif
	dump.signal = signr;
	dump_thread(regs, &dump);

/* If the size of the dump file exceeds the rlimit, then see what would happen
   if we wrote the stack, but not the data area.  */
#ifdef __sparc__
	if ((dump.u_dsize+dump.u_ssize) >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_dsize = 0;
#else
	if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_dsize = 0;
#endif

/* Make sure we have enough room to write the stack and data areas. */
#ifdef __sparc__
	if ((dump.u_ssize) >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_ssize = 0;
#else
	if ((dump.u_ssize+1) * PAGE_SIZE >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_ssize = 0;
#endif

/* make sure we actually have a data and stack area to dump */
	set_fs(USER_DS);
#ifdef __sparc__
	if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize))
		dump.u_dsize = 0;
	if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize))
		dump.u_ssize = 0;
#else
	if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
		dump.u_dsize = 0;
	if (verify_area(VERIFY_READ, (void *) START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
		dump.u_ssize = 0;
#endif

	set_fs(KERNEL_DS);
/* struct user */
	DUMP_WRITE(&dump,sizeof(dump));
/* Now dump all of the user data.  Include malloced stuff as well */
#ifndef __sparc__
	DUMP_SEEK(PAGE_SIZE);
#endif
/* now we start writing out the user space info */
	set_fs(USER_DS);
/* Dump the data area */
	if (dump.u_dsize != 0) {
		dump_start = START_DATA(dump);
#ifdef __sparc__
		dump_size = dump.u_dsize;
#else
		dump_size = dump.u_dsize << PAGE_SHIFT;
#endif
		DUMP_WRITE(dump_start,dump_size);
	}
/* Now prepare to dump the stack area */
	if (dump.u_ssize != 0) {
		dump_start = START_STACK(dump);
#ifdef __sparc__
		dump_size = dump.u_ssize;
#else
		dump_size = dump.u_ssize << PAGE_SHIFT;
#endif
		DUMP_WRITE(dump_start,dump_size);
	}
/* Finally dump the task struct.  Not be used by gdb, but could be useful */
	set_fs(KERNEL_DS);
	DUMP_WRITE(current,sizeof(*current));
end_coredump:
	set_fs(fs);
	return has_dumped;
}
Beispiel #7
0
/*
 * 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)
{
	int has_dumped = 0;
	struct file file;
	struct dentry *dentry;
	struct inode *inode;
	mm_segment_t fs;
	char corefile[6+sizeof(current->comm)];
	int segs;
	int i;
	size_t size;
	struct vm_area_struct *vma;
	struct elfhdr elf;
	off_t offset = 0, dataoff;
	unsigned long limit = current->rlim[RLIMIT_CORE].rlim_cur;
	int numnote = 4;
	struct memelfnote notes[4];
	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
	elf_fpregset_t fpu;		/* NT_PRFPREG */
	struct elf_prpsinfo psinfo;	/* NT_PRPSINFO */

	if (!current->dumpable ||
	    limit < ELF_EXEC_PAGESIZE ||
	    atomic_read(&current->mm->count) != 1)
		return 0;
	current->dumpable = 0;

#ifndef CONFIG_BINFMT_ELF
	MOD_INC_USE_COUNT;
#endif

	/* Count what's needed to dump, up to the limit of coredump size */
	segs = 0;
	size = 0;
	for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
		if (maydump(vma))
		{
			unsigned long sz = vma->vm_end-vma->vm_start;

			if (size+sz >= limit)
				break;
			else
				size += sz;
		}

		segs++;
	}
#ifdef DEBUG
	printk("elf_core_dump: %d segs taking %d bytes\n", segs, size);
#endif

	/* Set up header */
	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;
	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(elf);
	elf.e_shoff = 0;
	elf.e_flags = 0;
	elf.e_ehsize = sizeof(elf);
	elf.e_phentsize = sizeof(struct elf_phdr);
	elf.e_phnum = segs+1;		/* Include notes */
	elf.e_shentsize = 0;
	elf.e_shnum = 0;
	elf.e_shstrndx = 0;

	fs = get_fs();
	set_fs(KERNEL_DS);
	memcpy(corefile,"core.",5);
#if 0
	memcpy(corefile+5,current->comm,sizeof(current->comm));
#else
	corefile[4] = '\0';
#endif
	dentry = open_namei(corefile, O_CREAT | 2 | O_TRUNC | O_NOFOLLOW, 0600);
	if (IS_ERR(dentry)) {
		dentry = NULL;
		goto end_coredump;
	}
	inode = dentry->d_inode;

	if(inode->i_nlink > 1)
		goto end_coredump;	/* multiple links - don't dump */

	if (!S_ISREG(inode->i_mode))
		goto end_coredump;
	if (!inode->i_op || !inode->i_op->default_file_ops)
		goto end_coredump;
	if (init_private_file(&file, dentry, 3))
		goto end_coredump;
	if (!file.f_op->write)
		goto close_coredump;
	has_dumped = 1;
	current->flags |= PF_DUMPCORE;

	DUMP_WRITE(&elf, sizeof(elf));
	offset += sizeof(elf);				/* Elf header */
	offset += (segs+1) * sizeof(struct elf_phdr);	/* Program headers */

	/*
	 * Set up the notes in similar form to SVR4 core dumps made
	 * with info from their /proc.
	 */
	memset(&psinfo, 0, sizeof(psinfo));
	memset(&prstatus, 0, sizeof(prstatus));

	notes[0].name = "CORE";
	notes[0].type = NT_PRSTATUS;
	notes[0].datasz = sizeof(prstatus);
	notes[0].data = &prstatus;
	prstatus.pr_info.si_signo = prstatus.pr_cursig = signr;
	prstatus.pr_sigpend = current->signal.sig[0];
	prstatus.pr_sighold = current->blocked.sig[0];
	psinfo.pr_pid = prstatus.pr_pid = current->pid;
	psinfo.pr_ppid = prstatus.pr_ppid = current->p_pptr->pid;
	psinfo.pr_pgrp = prstatus.pr_pgrp = current->pgrp;
	psinfo.pr_sid = prstatus.pr_sid = current->session;
	prstatus.pr_utime.tv_sec = CT_TO_SECS(current->times.tms_utime);
	prstatus.pr_utime.tv_usec = CT_TO_USECS(current->times.tms_utime);
	prstatus.pr_stime.tv_sec = CT_TO_SECS(current->times.tms_stime);
	prstatus.pr_stime.tv_usec = CT_TO_USECS(current->times.tms_stime);
	prstatus.pr_cutime.tv_sec = CT_TO_SECS(current->times.tms_cutime);
	prstatus.pr_cutime.tv_usec = CT_TO_USECS(current->times.tms_cutime);
	prstatus.pr_cstime.tv_sec = CT_TO_SECS(current->times.tms_cstime);
	prstatus.pr_cstime.tv_usec = CT_TO_USECS(current->times.tms_cstime);

	/*
	 * This transfers the registers from regs into the standard
	 * coredump arrangement, whatever that is.
	 */
#ifdef ELF_CORE_COPY_REGS
	ELF_CORE_COPY_REGS(prstatus.pr_reg, regs)
#else
	if (sizeof(elf_gregset_t) != sizeof(struct pt_regs))
	{
		printk("sizeof(elf_gregset_t) (%ld) != sizeof(struct pt_regs) (%ld)\n",
			(long)sizeof(elf_gregset_t), (long)sizeof(struct pt_regs));
	}
	else
		*(struct pt_regs *)&prstatus.pr_reg = *regs;
#endif

#ifdef DEBUG
	dump_regs("Passed in regs", (elf_greg_t *)regs);
	dump_regs("prstatus regs", (elf_greg_t *)&prstatus.pr_reg);
#endif

	notes[1].name = "CORE";
	notes[1].type = NT_PRPSINFO;
	notes[1].datasz = sizeof(psinfo);
	notes[1].data = &psinfo;
	i = current->state ? ffz(~current->state) + 1 : 0;
	psinfo.pr_state = i;
	psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i];
	psinfo.pr_zomb = psinfo.pr_sname == 'Z';
	psinfo.pr_nice = current->priority-15;
	psinfo.pr_flag = current->flags;
	psinfo.pr_uid = current->uid;
	psinfo.pr_gid = current->gid;
	{
		int i, len;

		set_fs(fs);

		len = current->mm->arg_end - current->mm->arg_start;
		if (len >= ELF_PRARGSZ)
			len = ELF_PRARGSZ-1;
		copy_from_user(&psinfo.pr_psargs,
			      (const char *)current->mm->arg_start, len);
		for(i = 0; i < len; i++)
			if (psinfo.pr_psargs[i] == 0)
				psinfo.pr_psargs[i] = ' ';
		psinfo.pr_psargs[len] = 0;

		set_fs(KERNEL_DS);
	}
	strncpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname));

	notes[2].name = "CORE";
	notes[2].type = NT_TASKSTRUCT;
	notes[2].datasz = sizeof(*current);
	notes[2].data = current;

	/* Try to dump the FPU. */
	prstatus.pr_fpvalid = dump_fpu (regs, &fpu);
	if (!prstatus.pr_fpvalid)
	{
		numnote--;
	}
	else
	{
		notes[3].name = "CORE";
		notes[3].type = NT_PRFPREG;
		notes[3].datasz = sizeof(fpu);
		notes[3].data = &fpu;
	}
	
	/* Write notes phdr entry */
	{
		struct elf_phdr phdr;
		int sz = 0;

		for(i = 0; i < numnote; i++)
			sz += notesize(&notes[i]);

		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;

		offset += phdr.p_filesz;
		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, i = 0;
		i < segs && vma != NULL; vma = vma->vm_next) {
		struct elf_phdr phdr;
		size_t sz;

		i++;

		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));
	}

	for(i = 0; i < numnote; i++)
		if (!writenote(&notes[i], &file))
			goto close_coredump;

	set_fs(fs);

	DUMP_SEEK(dataoff);

	for(i = 0, vma = current->mm->mmap;
	    i < segs && vma != NULL;
	    vma = vma->vm_next) {
		unsigned long addr = vma->vm_start;
		unsigned long len = vma->vm_end - vma->vm_start;

		i++;
		if (!maydump(vma))
			continue;
#ifdef DEBUG
		printk("elf_core_dump: writing %08lx %lx\n", addr, len);
#endif
		DUMP_WRITE((void *)addr, len);
	}

	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);
	}

 close_coredump:
	if (file.f_op->release)
		file.f_op->release(inode,&file);

 end_coredump:
	set_fs(fs);
	dput(dentry);
#ifndef CONFIG_BINFMT_ELF
	MOD_DEC_USE_COUNT;
#endif
	return has_dumped;
}
Beispiel #8
0
static inline int
do_aout_core_dump(long signr, struct pt_regs * regs)
{
	struct inode * inode = NULL;
	struct file file;
	unsigned short fs;
	int has_dumped = 0;
	char corefile[6+sizeof(current->comm)];
	unsigned long dump_start, dump_size;
	struct user dump;
#ifdef __alpha__
#       define START_DATA(u)	(u.start_data)
#elif defined(CONFIG_ARM)
#	define START_DATA(u)	((u.u_tsize << PAGE_SHIFT) + u.start_code)
#else
#       define START_DATA(u)	(u.u_tsize << PAGE_SHIFT)
#endif

	if (!current->dumpable || current->mm->count != 1)
		return 0;
	current->dumpable = 0;

/* See if we have enough room to write the upage.  */
	if (current->rlim[RLIMIT_CORE].rlim_cur < PAGE_SIZE)
		return 0;
	fs = get_fs();
	set_fs(KERNEL_DS);
	memcpy(corefile,"core.",5);
#if 0
	memcpy(corefile+5,current->comm,sizeof(current->comm));
#else
	corefile[4] = '\0';
#endif
	if (open_namei(corefile,O_CREAT | 2 | O_TRUNC,0600,&inode,NULL)) {
		inode = NULL;
		goto end_coredump;
	}
	if (!S_ISREG(inode->i_mode))
		goto end_coredump;
	if (!inode->i_op || !inode->i_op->default_file_ops)
		goto end_coredump;
	if (get_write_access(inode))
		goto end_coredump;
	file.f_mode = 3;
	file.f_flags = 0;
	file.f_count = 1;
	file.f_inode = inode;
	file.f_pos = 0;
	file.f_reada = 0;
	file.f_op = inode->i_op->default_file_ops;
	if (file.f_op->open)
		if (file.f_op->open(inode,&file))
			goto done_coredump;
	if (!file.f_op->write)
		goto close_coredump;
	has_dumped = 1;
	current->flags |= PF_DUMPCORE;
       	strncpy(dump.u_comm, current->comm, sizeof(current->comm));
	dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));
	dump.signal = signr;
	dump_thread(regs, &dump);

/* If the size of the dump file exceeds the rlimit, then see what would happen
   if we wrote the stack, but not the data area.  */
	if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_dsize = 0;

/* Make sure we have enough room to write the stack and data areas. */
	if ((dump.u_ssize+1) * PAGE_SIZE >
	    current->rlim[RLIMIT_CORE].rlim_cur)
		dump.u_ssize = 0;

/* make sure we actually have a data and stack area to dump */
	set_fs(USER_DS);
	if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
		dump.u_dsize = 0;
	if (verify_area(VERIFY_READ, (void *) dump.start_stack, dump.u_ssize << PAGE_SHIFT))
		dump.u_ssize = 0;

	set_fs(KERNEL_DS);
/* struct user */
	DUMP_WRITE(&dump,sizeof(dump));
/* Now dump all of the user data.  Include malloced stuff as well */
	DUMP_SEEK(PAGE_SIZE);
/* now we start writing out the user space info */
	set_fs(USER_DS);
/* Dump the data area */
	if (dump.u_dsize != 0) {
		dump_start = START_DATA(dump);
		dump_size = dump.u_dsize << PAGE_SHIFT;
		DUMP_WRITE(dump_start,dump_size);
	}
/* Now prepare to dump the stack area */
	if (dump.u_ssize != 0) {
		dump_start = dump.start_stack;
		dump_size = dump.u_ssize << PAGE_SHIFT;
		DUMP_WRITE(dump_start,dump_size);
	}
/* Finally dump the task struct.  Not be used by gdb, but could be useful */
	set_fs(KERNEL_DS);
	DUMP_WRITE(current,sizeof(*current));
close_coredump:
	if (file.f_op->release)
		file.f_op->release(inode,&file);
done_coredump:
	put_write_access(inode);
end_coredump:
	set_fs(fs);
	iput(inode);
	return has_dumped;
}
/* 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 irix_core_dump(long signr, struct pt_regs * regs, struct file *file)
{
	int has_dumped = 0;
	mm_segment_t fs;
	int segs;
	int i;
	size_t size;
	struct vm_area_struct *vma;
	struct elfhdr elf;
	off_t offset = 0, dataoff;
	int limit = current->rlim[RLIMIT_CORE].rlim_cur;
	int numnote = 4;
	struct memelfnote notes[4];
	struct elf_prstatus prstatus;	/* NT_PRSTATUS */
	elf_fpregset_t fpu;		/* NT_PRFPREG */
	struct elf_prpsinfo psinfo;	/* NT_PRPSINFO */

	/* Count what's needed to dump, up to the limit of coredump size. */
	segs = 0;
	size = 0;
	for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
		if (maydump(vma))
		{
			int sz = vma->vm_end-vma->vm_start;

			if (size+sz >= limit)
				break;
			else
				size += sz;
		}

		segs++;
	}
#ifdef DEBUG
	printk("irix_core_dump: %d segs taking %d bytes\n", segs, size);
#endif

	/* Set up header. */
	memcpy(elf.e_ident, ELFMAG, SELFMAG);
	elf.e_ident[EI_CLASS] = ELFCLASS32;
	elf.e_ident[EI_DATA] = ELFDATA2LSB;
	elf.e_ident[EI_VERSION] = EV_CURRENT;
	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(elf);
	elf.e_shoff = 0;
	elf.e_flags = 0;
	elf.e_ehsize = sizeof(elf);
	elf.e_phentsize = sizeof(struct elf_phdr);
	elf.e_phnum = segs+1;		/* Include notes. */
	elf.e_shentsize = 0;
	elf.e_shnum = 0;
	elf.e_shstrndx = 0;

	fs = get_fs();
	set_fs(KERNEL_DS);

	has_dumped = 1;
	current->flags |= PF_DUMPCORE;

	DUMP_WRITE(&elf, sizeof(elf));
	offset += sizeof(elf);				/* Elf header. */
	offset += (segs+1) * sizeof(struct elf_phdr);	/* Program headers. */

	/* Set up the notes in similar form to SVR4 core dumps made
	 * with info from their /proc.
	 */
	memset(&psinfo, 0, sizeof(psinfo));
	memset(&prstatus, 0, sizeof(prstatus));

	notes[0].name = "CORE";
	notes[0].type = NT_PRSTATUS;
	notes[0].datasz = sizeof(prstatus);
	notes[0].data = &prstatus;
	prstatus.pr_info.si_signo = prstatus.pr_cursig = signr;
	prstatus.pr_sigpend = current->pending.signal.sig[0];
	prstatus.pr_sighold = current->blocked.sig[0];
	psinfo.pr_pid = prstatus.pr_pid = current->pid;
	psinfo.pr_ppid = prstatus.pr_ppid = current->p_pptr->pid;
	psinfo.pr_pgrp = prstatus.pr_pgrp = current->pgrp;
	psinfo.pr_sid = prstatus.pr_sid = current->session;
	prstatus.pr_utime.tv_sec = CT_TO_SECS(current->times.tms_utime);
	prstatus.pr_utime.tv_usec = CT_TO_USECS(current->times.tms_utime);
	prstatus.pr_stime.tv_sec = CT_TO_SECS(current->times.tms_stime);
	prstatus.pr_stime.tv_usec = CT_TO_USECS(current->times.tms_stime);
	prstatus.pr_cutime.tv_sec = CT_TO_SECS(current->times.tms_cutime);
	prstatus.pr_cutime.tv_usec = CT_TO_USECS(current->times.tms_cutime);
	prstatus.pr_cstime.tv_sec = CT_TO_SECS(current->times.tms_cstime);
	prstatus.pr_cstime.tv_usec = CT_TO_USECS(current->times.tms_cstime);
	if (sizeof(elf_gregset_t) != sizeof(struct pt_regs)) {
		printk("sizeof(elf_gregset_t) (%d) != sizeof(struct pt_regs) "
		       "(%d)\n", sizeof(elf_gregset_t), sizeof(struct pt_regs));
	} else {
		*(struct pt_regs *)&prstatus.pr_reg = *regs;
	}

	notes[1].name = "CORE";
	notes[1].type = NT_PRPSINFO;
	notes[1].datasz = sizeof(psinfo);
	notes[1].data = &psinfo;
	i = current->state ? ffz(~current->state) + 1 : 0;
	psinfo.pr_state = i;
	psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i];
	psinfo.pr_zomb = psinfo.pr_sname == 'Z';
	psinfo.pr_nice = current->nice;
	psinfo.pr_flag = current->flags;
	psinfo.pr_uid = current->uid;
	psinfo.pr_gid = current->gid;
	{
		int i, len;

		set_fs(fs);

		len = current->mm->arg_end - current->mm->arg_start;
		len = len >= ELF_PRARGSZ ? ELF_PRARGSZ : len;
		copy_from_user(&psinfo.pr_psargs,
			       (const char *)current->mm->arg_start, len);
		for(i = 0; i < len; i++)
			if (psinfo.pr_psargs[i] == 0)
				psinfo.pr_psargs[i] = ' ';
		psinfo.pr_psargs[len] = 0;

		set_fs(KERNEL_DS);
	}
	strncpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname));

	notes[2].name = "CORE";
	notes[2].type = NT_TASKSTRUCT;
	notes[2].datasz = sizeof(*current);
	notes[2].data = current;

	/* Try to dump the FPU. */
	prstatus.pr_fpvalid = dump_fpu (&fpu);
	if (!prstatus.pr_fpvalid) {
		numnote--;
	} else {
		notes[3].name = "CORE";
		notes[3].type = NT_PRFPREG;
		notes[3].datasz = sizeof(fpu);
		notes[3].data = &fpu;
	}

	/* Write notes phdr entry. */
	{
		struct elf_phdr phdr;
		int sz = 0;

		for(i = 0; i < numnote; i++)
			sz += notesize(&notes[i]);

		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;

		offset += phdr.p_filesz;
		DUMP_WRITE(&phdr, sizeof(phdr));
	}

	/* Page-align dumped data. */
	dataoff = offset = roundup(offset, PAGE_SIZE);

	/* Write program headers for segments dump. */
	for(vma = current->mm->mmap, i = 0;
		i < segs && vma != NULL; vma = vma->vm_next) {
		struct elf_phdr phdr;
		size_t sz;

		i++;

		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 = PAGE_SIZE;

		DUMP_WRITE(&phdr, sizeof(phdr));
	}

	for(i = 0; i < numnote; i++)
		if (!writenote(&notes[i], file))
			goto end_coredump;

	set_fs(fs);

	DUMP_SEEK(dataoff);

	for(i = 0, vma = current->mm->mmap;
	    i < segs && vma != NULL;
	    vma = vma->vm_next) {
		unsigned long addr = vma->vm_start;
		unsigned long len = vma->vm_end - vma->vm_start;

		if (!maydump(vma))
			continue;
		i++;
#ifdef DEBUG
		printk("elf_core_dump: writing %08lx %lx\n", addr, len);
#endif
		DUMP_WRITE((void *)addr, len);
	}

	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);
	return has_dumped;
}