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linux/arch/mips/kernel/irixelf.c
Eric W. Biederman a928972864 [PATCH] Don't uselessly export task_struct to userspace in core dumps 
task_struct is an internal structure to the kernel with a lot of good
information, that is probably interesting in core dumps.  However there is
no way for user space to know what format that information is in making it
useless.

I grepped the GDB 6.3 source code and NT_TASKSTRUCT while defined is not
used anywhere else.  So I would be surprised if anyone notices it is
missing.

In addition exporting kernel pointers to all the interesting kernel data
structures sounds like the very definition of an information leak.  I
haven't a clue what someone with evil intentions could do with that
information, but in any attack against the kernel it looks like this is the
perfect tool for aiming that attack.

So since NT_TASKSTRUCT is useless as currently defined and is potentially
dangerous, let's just not export it.

(akpm: Daniel Jacobowitz <dan@debian.org> "would be amazed" if anything was
using NT_TASKSTRUCT).

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:18 -08:00

1338 lines
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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* irixelf.c: Code to load IRIX ELF executables conforming to the MIPS ABI.
* Based off of work by Eric Youngdale.
*
* Copyright (C) 1993 - 1994 Eric Youngdale <ericy@cais.com>
* Copyright (C) 1996 - 2004 David S. Miller <dm@engr.sgi.com>
* Copyright (C) 2004 - 2005 Steven J. Hill <sjhill@realitydiluted.com>
*/
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/a.out.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/signal.h>
#include <linux/binfmts.h>
#include <linux/string.h>
#include <linux/file.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/shm.h>
#include <linux/personality.h>
#include <linux/elfcore.h>
#include <linux/smp_lock.h>
#include <asm/mipsregs.h>
#include <asm/namei.h>
#include <asm/prctl.h>
#include <asm/uaccess.h>
#define DLINFO_ITEMS 12
#include <linux/elf.h>
#undef DEBUG
static int load_irix_binary(struct linux_binprm * bprm, struct pt_regs * regs);
static int load_irix_library(struct file *);
static int irix_core_dump(long signr, struct pt_regs * regs,
struct file *file);
static struct linux_binfmt irix_format = {
NULL, THIS_MODULE, load_irix_binary, load_irix_library,
irix_core_dump, PAGE_SIZE
};
#ifndef elf_addr_t
#define elf_addr_t unsigned long
#endif
#ifdef DEBUG
/* Debugging routines. */
static char *get_elf_p_type(Elf32_Word p_type)
{
int i = (int) p_type;
switch(i) {
case PT_NULL: return("PT_NULL"); break;
case PT_LOAD: return("PT_LOAD"); break;
case PT_DYNAMIC: return("PT_DYNAMIC"); break;
case PT_INTERP: return("PT_INTERP"); break;
case PT_NOTE: return("PT_NOTE"); break;
case PT_SHLIB: return("PT_SHLIB"); break;
case PT_PHDR: return("PT_PHDR"); break;
case PT_LOPROC: return("PT_LOPROC/REGINFO"); break;
case PT_HIPROC: return("PT_HIPROC"); break;
default: return("PT_BOGUS"); break;
}
}
static void print_elfhdr(struct elfhdr *ehp)
{
int i;
printk("ELFHDR: e_ident<");
for(i = 0; i < (EI_NIDENT - 1); i++) printk("%x ", ehp->e_ident[i]);
printk("%x>\n", ehp->e_ident[i]);
printk(" e_type[%04x] e_machine[%04x] e_version[%08lx]\n",
(unsigned short) ehp->e_type, (unsigned short) ehp->e_machine,
(unsigned long) ehp->e_version);
printk(" e_entry[%08lx] e_phoff[%08lx] e_shoff[%08lx] "
"e_flags[%08lx]\n",
(unsigned long) ehp->e_entry, (unsigned long) ehp->e_phoff,
(unsigned long) ehp->e_shoff, (unsigned long) ehp->e_flags);
printk(" e_ehsize[%04x] e_phentsize[%04x] e_phnum[%04x]\n",
(unsigned short) ehp->e_ehsize, (unsigned short) ehp->e_phentsize,
(unsigned short) ehp->e_phnum);
printk(" e_shentsize[%04x] e_shnum[%04x] e_shstrndx[%04x]\n",
(unsigned short) ehp->e_shentsize, (unsigned short) ehp->e_shnum,
(unsigned short) ehp->e_shstrndx);
}
static void print_phdr(int i, struct elf_phdr *ep)
{
printk("PHDR[%d]: p_type[%s] p_offset[%08lx] p_vaddr[%08lx] "
"p_paddr[%08lx]\n", i, get_elf_p_type(ep->p_type),
(unsigned long) ep->p_offset, (unsigned long) ep->p_vaddr,
(unsigned long) ep->p_paddr);
printk(" p_filesz[%08lx] p_memsz[%08lx] p_flags[%08lx] "
"p_align[%08lx]\n", (unsigned long) ep->p_filesz,
(unsigned long) ep->p_memsz, (unsigned long) ep->p_flags,
(unsigned long) ep->p_align);
}
static void dump_phdrs(struct elf_phdr *ep, int pnum)
{
int i;
for(i = 0; i < pnum; i++, ep++) {
if((ep->p_type == PT_LOAD) ||
(ep->p_type == PT_INTERP) ||
(ep->p_type == PT_PHDR))
print_phdr(i, ep);
}
}
#endif /* DEBUG */
static void set_brk(unsigned long start, unsigned long end)
{
start = PAGE_ALIGN(start);
end = PAGE_ALIGN(end);
if (end <= start)
return;
down_write(&current->mm->mmap_sem);
do_brk(start, end - start);
up_write(&current->mm->mmap_sem);
}
/* We need to explicitly zero any fractional pages
* after the data section (i.e. bss). This would
* contain the junk from the file that should not
* be in memory.
*/
static void padzero(unsigned long elf_bss)
{
unsigned long nbyte;
nbyte = elf_bss & (PAGE_SIZE-1);
if (nbyte) {
nbyte = PAGE_SIZE - nbyte;
clear_user((void __user *) elf_bss, nbyte);
}
}
static unsigned long * create_irix_tables(char * p, int argc, int envc,
struct elfhdr * exec, unsigned int load_addr,
unsigned int interp_load_addr, struct pt_regs *regs,
struct elf_phdr *ephdr)
{
elf_addr_t *argv;
elf_addr_t *envp;
elf_addr_t *sp, *csp;
#ifdef DEBUG
printk("create_irix_tables: p[%p] argc[%d] envc[%d] "
"load_addr[%08x] interp_load_addr[%08x]\n",
p, argc, envc, load_addr, interp_load_addr);
#endif
sp = (elf_addr_t *) (~15UL & (unsigned long) p);
csp = sp;
csp -= exec ? DLINFO_ITEMS*2 : 2;
csp -= envc+1;
csp -= argc+1;
csp -= 1; /* argc itself */
if ((unsigned long)csp & 15UL) {
sp -= (16UL - ((unsigned long)csp & 15UL)) / sizeof(*sp);
}
/*
* Put the ELF interpreter info on the stack
*/
#define NEW_AUX_ENT(nr, id, val) \
__put_user ((id), sp+(nr*2)); \
__put_user ((val), sp+(nr*2+1)); \
sp -= 2;
NEW_AUX_ENT(0, AT_NULL, 0);
if(exec) {
sp -= 11*2;
NEW_AUX_ENT (0, AT_PHDR, load_addr + exec->e_phoff);
NEW_AUX_ENT (1, AT_PHENT, sizeof (struct elf_phdr));
NEW_AUX_ENT (2, AT_PHNUM, exec->e_phnum);
NEW_AUX_ENT (3, AT_PAGESZ, ELF_EXEC_PAGESIZE);
NEW_AUX_ENT (4, AT_BASE, interp_load_addr);
NEW_AUX_ENT (5, AT_FLAGS, 0);
NEW_AUX_ENT (6, AT_ENTRY, (elf_addr_t) exec->e_entry);
NEW_AUX_ENT (7, AT_UID, (elf_addr_t) current->uid);
NEW_AUX_ENT (8, AT_EUID, (elf_addr_t) current->euid);
NEW_AUX_ENT (9, AT_GID, (elf_addr_t) current->gid);
NEW_AUX_ENT (10, AT_EGID, (elf_addr_t) current->egid);
}
#undef NEW_AUX_ENT
sp -= envc+1;
envp = sp;
sp -= argc+1;
argv = sp;
__put_user((elf_addr_t)argc,--sp);
current->mm->arg_start = (unsigned long) p;
while (argc-->0) {
__put_user((unsigned long)p,argv++);
p += strlen_user(p);
}
__put_user((unsigned long) NULL, argv);
current->mm->arg_end = current->mm->env_start = (unsigned long) p;
while (envc-->0) {
__put_user((unsigned long)p,envp++);
p += strlen_user(p);
}
__put_user((unsigned long) NULL, envp);
current->mm->env_end = (unsigned long) p;
return sp;
}
/* This is much more generalized than the library routine read function,
* so we keep this separate. Technically the library read function
* is only provided so that we can read a.out libraries that have
* an ELF header.
*/
static unsigned int load_irix_interp(struct elfhdr * interp_elf_ex,
struct file * interpreter,
unsigned int *interp_load_addr)
{
struct elf_phdr *elf_phdata = NULL;
struct elf_phdr *eppnt;
unsigned int len;
unsigned int load_addr;
int elf_bss;
int retval;
unsigned int last_bss;
int error;
int i;
unsigned int k;
elf_bss = 0;
last_bss = 0;
error = load_addr = 0;
#ifdef DEBUG
print_elfhdr(interp_elf_ex);
#endif
/* First of all, some simple consistency checks */
if ((interp_elf_ex->e_type != ET_EXEC &&
interp_elf_ex->e_type != ET_DYN) ||
!interpreter->f_op->mmap) {
printk("IRIX interp has bad e_type %d\n", interp_elf_ex->e_type);
return 0xffffffff;
}
/* Now read in all of the header information */
if(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum > PAGE_SIZE) {
printk("IRIX interp header bigger than a page (%d)\n",
(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum));
return 0xffffffff;
}
elf_phdata = kmalloc(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum,
GFP_KERNEL);
if(!elf_phdata) {
printk("Cannot kmalloc phdata for IRIX interp.\n");
return 0xffffffff;
}
/* If the size of this structure has changed, then punt, since
* we will be doing the wrong thing.
*/
if(interp_elf_ex->e_phentsize != 32) {
printk("IRIX interp e_phentsize == %d != 32 ",
interp_elf_ex->e_phentsize);
kfree(elf_phdata);
return 0xffffffff;
}
retval = kernel_read(interpreter, interp_elf_ex->e_phoff,
(char *) elf_phdata,
sizeof(struct elf_phdr) * interp_elf_ex->e_phnum);
#ifdef DEBUG
dump_phdrs(elf_phdata, interp_elf_ex->e_phnum);
#endif
eppnt = elf_phdata;
for(i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) {
if(eppnt->p_type == PT_LOAD) {
int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
int elf_prot = 0;
unsigned long vaddr = 0;
if (eppnt->p_flags & PF_R) elf_prot = PROT_READ;
if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
elf_type |= MAP_FIXED;
vaddr = eppnt->p_vaddr;
pr_debug("INTERP do_mmap(%p, %08lx, %08lx, %08lx, %08lx, %08lx) ",
interpreter, vaddr,
(unsigned long) (eppnt->p_filesz + (eppnt->p_vaddr & 0xfff)),
(unsigned long) elf_prot, (unsigned long) elf_type,
(unsigned long) (eppnt->p_offset & 0xfffff000));
down_write(&current->mm->mmap_sem);
error = do_mmap(interpreter, vaddr,
eppnt->p_filesz + (eppnt->p_vaddr & 0xfff),
elf_prot, elf_type,
eppnt->p_offset & 0xfffff000);
up_write(&current->mm->mmap_sem);
if(error < 0 && error > -1024) {
printk("Aieee IRIX interp mmap error=%d\n", error);
break; /* Real error */
}
pr_debug("error=%08lx ", (unsigned long) error);
if(!load_addr && interp_elf_ex->e_type == ET_DYN) {
load_addr = error;
pr_debug("load_addr = error ");
}
/* Find the end of the file mapping for this phdr, and keep
* track of the largest address we see for this.
*/
k = eppnt->p_vaddr + eppnt->p_filesz;
if(k > elf_bss) elf_bss = k;
/* Do the same thing for the memory mapping - between
* elf_bss and last_bss is the bss section.
*/
k = eppnt->p_memsz + eppnt->p_vaddr;
if(k > last_bss) last_bss = k;
pr_debug("\n");
}
}
/* Now use mmap to map the library into memory. */
if(error < 0 && error > -1024) {
pr_debug("got error %d\n", error);
kfree(elf_phdata);
return 0xffffffff;
}
/* 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.
*/
pr_debug("padzero(%08lx) ", (unsigned long) (elf_bss));
padzero(elf_bss);
len = (elf_bss + 0xfff) & 0xfffff000; /* What we have mapped so far */
pr_debug("last_bss[%08lx] len[%08lx]\n", (unsigned long) last_bss,
(unsigned long) len);
/* Map the last of the bss segment */
if (last_bss > len) {
down_write(&current->mm->mmap_sem);
do_brk(len, (last_bss - len));
up_write(&current->mm->mmap_sem);
}
kfree(elf_phdata);
*interp_load_addr = load_addr;
return ((unsigned int) interp_elf_ex->e_entry);
}
/* Check sanity of IRIX elf executable header. */
static int verify_binary(struct elfhdr *ehp, struct linux_binprm *bprm)
{
if (memcmp(ehp->e_ident, ELFMAG, SELFMAG) != 0)
return -ENOEXEC;
/* First of all, some simple consistency checks */
if((ehp->e_type != ET_EXEC && ehp->e_type != ET_DYN) ||
!bprm->file->f_op->mmap) {
return -ENOEXEC;
}
/* XXX Don't support N32 or 64bit binaries yet because they can
* XXX and do execute 64 bit instructions and expect all registers
* XXX to be 64 bit as well. We need to make the kernel save
* XXX all registers as 64bits on cpu's capable of this at
* XXX exception time plus frob the XTLB exception vector.
*/
if((ehp->e_flags & EF_MIPS_ABI2))
return -ENOEXEC;
return 0;
}
/*
* This is where the detailed check is performed. Irix binaries
* use interpreters with 'libc.so' in the name, so this function
* can differentiate between Linux and Irix binaries.
*/
static inline int look_for_irix_interpreter(char **name,
struct file **interpreter,
struct elfhdr *interp_elf_ex,
struct elf_phdr *epp,
struct linux_binprm *bprm, int pnum)
{
int i;
int retval = -EINVAL;
struct file *file = NULL;
*name = NULL;
for(i = 0; i < pnum; i++, epp++) {
if (epp->p_type != PT_INTERP)
continue;
/* It is illegal to have two interpreters for one executable. */
if (*name != NULL)
goto out;
*name = kmalloc(epp->p_filesz + strlen(IRIX_EMUL), GFP_KERNEL);
if (!*name)
return -ENOMEM;
strcpy(*name, IRIX_EMUL);
retval = kernel_read(bprm->file, epp->p_offset, (*name + 16),
epp->p_filesz);
if (retval < 0)
goto out;
file = open_exec(*name);
if (IS_ERR(file)) {
retval = PTR_ERR(file);
goto out;
}
retval = kernel_read(file, 0, bprm->buf, 128);
if (retval < 0)
goto dput_and_out;
*interp_elf_ex = *(struct elfhdr *) bprm->buf;
}
*interpreter = file;
return 0;
dput_and_out:
fput(file);
out:
kfree(*name);
return retval;
}
static inline int verify_irix_interpreter(struct elfhdr *ihp)
{
if (memcmp(ihp->e_ident, ELFMAG, SELFMAG) != 0)
return -ELIBBAD;
return 0;
}
#define EXEC_MAP_FLAGS (MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE)
static inline void map_executable(struct file *fp, struct elf_phdr *epp, int pnum,
unsigned int *estack, unsigned int *laddr,
unsigned int *scode, unsigned int *ebss,
unsigned int *ecode, unsigned int *edata,
unsigned int *ebrk)
{
unsigned int tmp;
int i, prot;
for(i = 0; i < pnum; i++, epp++) {
if(epp->p_type != PT_LOAD)
continue;
/* Map it. */
prot = (epp->p_flags & PF_R) ? PROT_READ : 0;
prot |= (epp->p_flags & PF_W) ? PROT_WRITE : 0;
prot |= (epp->p_flags & PF_X) ? PROT_EXEC : 0;
down_write(&current->mm->mmap_sem);
(void) do_mmap(fp, (epp->p_vaddr & 0xfffff000),
(epp->p_filesz + (epp->p_vaddr & 0xfff)),
prot, EXEC_MAP_FLAGS,
(epp->p_offset & 0xfffff000));
up_write(&current->mm->mmap_sem);
/* Fixup location tracking vars. */
if((epp->p_vaddr & 0xfffff000) < *estack)
*estack = (epp->p_vaddr & 0xfffff000);
if(!*laddr)
*laddr = epp->p_vaddr - epp->p_offset;
if(epp->p_vaddr < *scode)
*scode = epp->p_vaddr;
tmp = epp->p_vaddr + epp->p_filesz;
if(tmp > *ebss)
*ebss = tmp;
if((epp->p_flags & PF_X) && *ecode < tmp)
*ecode = tmp;
if(*edata < tmp)
*edata = tmp;
tmp = epp->p_vaddr + epp->p_memsz;
if(tmp > *ebrk)
*ebrk = tmp;
}
}
static inline int map_interpreter(struct elf_phdr *epp, struct elfhdr *ihp,
struct file *interp, unsigned int *iladdr,
int pnum, mm_segment_t old_fs,
unsigned int *eentry)
{
int i;
*eentry = 0xffffffff;
for(i = 0; i < pnum; i++, epp++) {
if(epp->p_type != PT_INTERP)
continue;
/* We should have fielded this error elsewhere... */
if(*eentry != 0xffffffff)
return -1;
set_fs(old_fs);
*eentry = load_irix_interp(ihp, interp, iladdr);
old_fs = get_fs();
set_fs(get_ds());
fput(interp);
if (*eentry == 0xffffffff)
return -1;
}
return 0;
}
/*
* IRIX maps a page at 0x200000 that holds information about the
* process and the system, here we map the page and fill the
* structure
*/
static void irix_map_prda_page(void)
{
unsigned long v;
struct prda *pp;
down_write(&current->mm->mmap_sem);
v = do_brk (PRDA_ADDRESS, PAGE_SIZE);
up_write(&current->mm->mmap_sem);
if (v < 0)
return;
pp = (struct prda *) v;
pp->prda_sys.t_pid = current->pid;
pp->prda_sys.t_prid = read_c0_prid();
pp->prda_sys.t_rpid = current->pid;
/* We leave the rest set to zero */
}
/* These are the functions used to load ELF style executables and shared
* libraries. There is no binary dependent code anywhere else.
*/
static int load_irix_binary(struct linux_binprm * bprm, struct pt_regs * regs)
{
struct elfhdr elf_ex, interp_elf_ex;
struct file *interpreter;
struct elf_phdr *elf_phdata, *elf_ihdr, *elf_ephdr;
unsigned int load_addr, elf_bss, elf_brk;
unsigned int elf_entry, interp_load_addr = 0;
unsigned int start_code, end_code, end_data, elf_stack;
int retval, has_interp, has_ephdr, size, i;
char *elf_interpreter;
mm_segment_t old_fs;
load_addr = 0;
has_interp = has_ephdr = 0;
elf_ihdr = elf_ephdr = NULL;
elf_ex = *((struct elfhdr *) bprm->buf);
retval = -ENOEXEC;
if (verify_binary(&elf_ex, bprm))
goto out;
/*
* Telling -o32 static binaries from Linux and Irix apart from each
* other is difficult. There are 2 differences to be noted for static
* binaries from the 2 operating systems:
*
* 1) Irix binaries have their .text section before their .init
* section. Linux binaries are just the opposite.
*
* 2) Irix binaries usually have <= 12 sections and Linux
* binaries have > 20.
*
* We will use Method #2 since Method #1 would require us to read in
* the section headers which is way too much overhead. This appears
* to work for everything we have ran into so far. If anyone has a
* better method to tell the binaries apart, I'm listening.
*/
if (elf_ex.e_shnum > 20)
goto out;
#ifdef DEBUG
print_elfhdr(&elf_ex);
#endif
/* Now read in all of the header information */
size = elf_ex.e_phentsize * elf_ex.e_phnum;
if (size > 65536)
goto out;
elf_phdata = kmalloc(size, GFP_KERNEL);
if (elf_phdata == NULL) {
retval = -ENOMEM;
goto out;
}
retval = kernel_read(bprm->file, elf_ex.e_phoff, (char *)elf_phdata, size);
if (retval < 0)
goto out_free_ph;
#ifdef DEBUG
dump_phdrs(elf_phdata, elf_ex.e_phnum);
#endif
/* Set some things for later. */
for(i = 0; i < elf_ex.e_phnum; i++) {
switch(elf_phdata[i].p_type) {
case PT_INTERP:
has_interp = 1;
elf_ihdr = &elf_phdata[i];
break;
case PT_PHDR:
has_ephdr = 1;
elf_ephdr = &elf_phdata[i];
break;
};
}
pr_debug("\n");
elf_bss = 0;
elf_brk = 0;
elf_stack = 0xffffffff;
elf_interpreter = NULL;
start_code = 0xffffffff;
end_code = 0;
end_data = 0;
/*
* If we get a return value, we change the value to be ENOEXEC
* so that we can exit gracefully and the main binary format
* search loop in 'fs/exec.c' will move onto the next handler
* which should be the normal ELF binary handler.
*/
retval = look_for_irix_interpreter(&elf_interpreter, &interpreter,
&interp_elf_ex, elf_phdata, bprm,
elf_ex.e_phnum);
if (retval) {
retval = -ENOEXEC;
goto out_free_file;
}
if (elf_interpreter) {
retval = verify_irix_interpreter(&interp_elf_ex);
if(retval)
goto out_free_interp;
}
/* OK, we are done with that, now set up the arg stuff,
* and then start this sucker up.
*/
retval = -E2BIG;
if (!bprm->sh_bang && !bprm->p)
goto out_free_interp;
/* Flush all traces of the currently running executable */
retval = flush_old_exec(bprm);
if (retval)
goto out_free_dentry;
/* OK, This is the point of no return */
current->mm->end_data = 0;
current->mm->end_code = 0;
current->mm->mmap = NULL;
current->flags &= ~PF_FORKNOEXEC;
elf_entry = (unsigned int) elf_ex.e_entry;
/* Do this so that we can load the interpreter, if need be. We will
* change some of these later.
*/
setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
current->mm->start_stack = bprm->p;
/* At this point, we assume that the image should be loaded at
* fixed address, not at a variable address.
*/
old_fs = get_fs();
set_fs(get_ds());
map_executable(bprm->file, elf_phdata, elf_ex.e_phnum, &elf_stack,
&load_addr, &start_code, &elf_bss, &end_code,
&end_data, &elf_brk);
if(elf_interpreter) {
retval = map_interpreter(elf_phdata, &interp_elf_ex,
interpreter, &interp_load_addr,
elf_ex.e_phnum, old_fs, &elf_entry);
kfree(elf_interpreter);
if(retval) {
set_fs(old_fs);
printk("Unable to load IRIX ELF interpreter\n");
send_sig(SIGSEGV, current, 0);
retval = 0;
goto out_free_file;
}
}
set_fs(old_fs);
kfree(elf_phdata);
set_personality(PER_IRIX32);
set_binfmt(&irix_format);
compute_creds(bprm);
current->flags &= ~PF_FORKNOEXEC;
bprm->p = (unsigned long)
create_irix_tables((char *)bprm->p, bprm->argc, bprm->envc,
(elf_interpreter ? &elf_ex : NULL),
load_addr, interp_load_addr, regs, elf_ephdr);
current->mm->start_brk = current->mm->brk = elf_brk;
current->mm->end_code = end_code;
current->mm->start_code = start_code;
current->mm->end_data = end_data;
current->mm->start_stack = bprm->p;
/* Calling set_brk effectively mmaps the pages that we need for the
* bss and break sections.
*/
set_brk(elf_bss, elf_brk);
/*
* IRIX maps a page at 0x200000 which holds some system
* information. Programs depend on this.
*/
irix_map_prda_page();
padzero(elf_bss);
pr_debug("(start_brk) %lx\n" , (long) current->mm->start_brk);
pr_debug("(end_code) %lx\n" , (long) current->mm->end_code);
pr_debug("(start_code) %lx\n" , (long) current->mm->start_code);
pr_debug("(end_data) %lx\n" , (long) current->mm->end_data);
pr_debug("(start_stack) %lx\n" , (long) current->mm->start_stack);
pr_debug("(brk) %lx\n" , (long) current->mm->brk);
#if 0 /* XXX No fucking way dude... */
/* Why this, you ask??? Well SVr4 maps page 0 as read-only,
* and some applications "depend" upon this behavior.
* Since we do not have the power to recompile these, we
* emulate the SVr4 behavior. Sigh.
*/
down_write(&current->mm->mmap_sem);
(void) do_mmap(NULL, 0, 4096, PROT_READ | PROT_EXEC,
MAP_FIXED | MAP_PRIVATE, 0);
up_write(&current->mm->mmap_sem);
#endif
start_thread(regs, elf_entry, bprm->p);
if (current->ptrace & PT_PTRACED)
send_sig(SIGTRAP, current, 0);
return 0;
out:
return retval;
out_free_dentry:
allow_write_access(interpreter);
fput(interpreter);
out_free_interp:
kfree(elf_interpreter);
out_free_file:
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_irix_library(struct file *file)
{
struct elfhdr elf_ex;
struct elf_phdr *elf_phdata = NULL;
unsigned int len = 0;
int elf_bss = 0;
int retval;
unsigned int bss;
int error;
int i,j, k;
error = kernel_read(file, 0, (char *) &elf_ex, sizeof(elf_ex));
if (error != sizeof(elf_ex))
return -ENOEXEC;
if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
return -ENOEXEC;
/* First of all, some simple consistency checks. */
if(elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
!file->f_op->mmap)
return -ENOEXEC;
/* Now read in all of the header information. */
if(sizeof(struct elf_phdr) * elf_ex.e_phnum > PAGE_SIZE)
return -ENOEXEC;
elf_phdata = kmalloc(sizeof(struct elf_phdr) * elf_ex.e_phnum, GFP_KERNEL);
if (elf_phdata == NULL)
return -ENOMEM;
retval = kernel_read(file, elf_ex.e_phoff, (char *) elf_phdata,
sizeof(struct elf_phdr) * elf_ex.e_phnum);
j = 0;
for(i=0; i<elf_ex.e_phnum; i++)
if((elf_phdata + i)->p_type == PT_LOAD) j++;
if(j != 1) {
kfree(elf_phdata);
return -ENOEXEC;
}
while(elf_phdata->p_type != PT_LOAD) elf_phdata++;
/* Now use mmap to map the library into memory. */
down_write(&current->mm->mmap_sem);
error = do_mmap(file,
elf_phdata->p_vaddr & 0xfffff000,
elf_phdata->p_filesz + (elf_phdata->p_vaddr & 0xfff),
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,
elf_phdata->p_offset & 0xfffff000);
up_write(&current->mm->mmap_sem);
k = elf_phdata->p_vaddr + elf_phdata->p_filesz;
if (k > elf_bss) elf_bss = k;
if (error != (elf_phdata->p_vaddr & 0xfffff000)) {
kfree(elf_phdata);
return error;
}
padzero(elf_bss);
len = (elf_phdata->p_filesz + elf_phdata->p_vaddr+ 0xfff) & 0xfffff000;
bss = elf_phdata->p_memsz + elf_phdata->p_vaddr;
if (bss > len) {
down_write(&current->mm->mmap_sem);
do_brk(len, bss-len);
up_write(&current->mm->mmap_sem);
}
kfree(elf_phdata);
return 0;
}
/* Called through irix_syssgi() to map an elf image given an FD,
* a phdr ptr USER_PHDRP in userspace, and a count CNT telling how many
* phdrs there are in the USER_PHDRP array. We return the vaddr the
* first phdr was successfully mapped to.
*/
unsigned long irix_mapelf(int fd, struct elf_phdr __user *user_phdrp, int cnt)
{
unsigned long type, vaddr, filesz, offset, flags;
struct elf_phdr __user *hp;
struct file *filp;
int i, retval;
pr_debug("irix_mapelf: fd[%d] user_phdrp[%p] cnt[%d]\n",
fd, user_phdrp, cnt);
/* First get the verification out of the way. */
hp = user_phdrp;
if (!access_ok(VERIFY_READ, hp, (sizeof(struct elf_phdr) * cnt))) {
pr_debug("irix_mapelf: bad pointer to ELF PHDR!\n");
return -EFAULT;
}
#ifdef DEBUG
dump_phdrs(user_phdrp, cnt);
#endif
for (i = 0; i < cnt; i++, hp++) {
if (__get_user(type, &hp->p_type))
return -EFAULT;
if (type != PT_LOAD) {
printk("irix_mapelf: One section is not PT_LOAD!\n");
return -ENOEXEC;
}
}
filp = fget(fd);
if (!filp)
return -EACCES;
if(!filp->f_op) {
printk("irix_mapelf: Bogon filp!\n");
fput(filp);
return -EACCES;
}
hp = user_phdrp;
for(i = 0; i < cnt; i++, hp++) {
int prot;
retval = __get_user(vaddr, &hp->p_vaddr);
retval |= __get_user(filesz, &hp->p_filesz);
retval |= __get_user(offset, &hp->p_offset);
retval |= __get_user(flags, &hp->p_flags);
if (retval)
return retval;
prot = (flags & PF_R) ? PROT_READ : 0;
prot |= (flags & PF_W) ? PROT_WRITE : 0;
prot |= (flags & PF_X) ? PROT_EXEC : 0;
down_write(&current->mm->mmap_sem);
retval = do_mmap(filp, (vaddr & 0xfffff000),
(filesz + (vaddr & 0xfff)),
prot, (MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE),
(offset & 0xfffff000));
up_write(&current->mm->mmap_sem);
if (retval != (vaddr & 0xfffff000)) {
printk("irix_mapelf: do_mmap fails with %d!\n", retval);
fput(filp);
return retval;
}
}
pr_debug("irix_mapelf: Success, returning %08lx\n",
(unsigned long) user_phdrp->p_vaddr);
fput(filp);
if (__get_user(vaddr, &user_phdrp->p_vaddr))
return -EFAULT;
return vaddr;
}
/*
* 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 __user *addr, int nr)
{
return file->f_op->write(file, (const char __user *) addr, nr, &file->f_pos) == nr;
}
static int dump_seek(struct file *file, off_t off)
{
if (file->f_op->llseek) {
if (file->f_op->llseek(file, off, 0) != off)
return 0;
} else
file->f_pos = off;
return 1;
}
/* Decide whether a segment is worth dumping; default is yes to be
* sure (missing info is worse than too much; etc).
* Personally I'd include everything, and use the coredump limit...
*
* I think we should skip something. But I am not sure how. H.J.
*/
static inline int maydump(struct vm_area_struct *vma)
{
if (!(vma->vm_flags & (VM_READ|VM_WRITE|VM_EXEC)))
return 0;
#if 1
if (vma->vm_flags & (VM_WRITE|VM_GROWSUP|VM_GROWSDOWN))
return 1;
if (vma->vm_flags & (VM_READ|VM_EXEC|VM_EXECUTABLE|VM_SHARED))
return 0;
#endif
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), 4);
sz += roundup(en->datasz, 4);
return sz;
}
/* #define DEBUG */
#define DUMP_WRITE(addr, nr) \
if (!dump_write(file, (addr), (nr))) \
goto end_coredump;
#define DUMP_SEEK(off) \
if (!dump_seek(file, (off))) \
goto end_coredump;
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;
end_coredump:
return 0;
}
#undef DUMP_WRITE
#undef DUMP_SEEK
#define DUMP_WRITE(addr, nr) \
if (!dump_write(file, (addr), (nr))) \
goto end_coredump;
#define DUMP_SEEK(off) \
if (!dump_seek(file, (off))) \
goto end_coredump;
/* 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->signal->rlim[RLIMIT_CORE].rlim_cur;
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++;
}
#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;
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 = current->pid;
psinfo.pr_ppid = prstatus.pr_ppid = current->parent->pid;
psinfo.pr_pgrp = prstatus.pr_pgrp = process_group(current);
psinfo.pr_sid = prstatus.pr_sid = current->signal->session;
if (current->pid == current->tgid) {
/*
* 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++;
#ifdef DEBUG
printk("elf_core_dump: writing %08lx %lx\n", addr, len);
#endif
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;
}
static int __init init_irix_binfmt(void)
{
extern int init_inventory(void);
extern asmlinkage unsigned long sys_call_table;
extern asmlinkage unsigned long sys_call_table_irix5;
init_inventory();
/*
* Copy the IRIX5 syscall table (8000 bytes) into the main syscall
* table. The IRIX5 calls are located by an offset of 8000 bytes
* from the beginning of the main table.
*/
memcpy((void *) ((unsigned long) &sys_call_table + 8000),
&sys_call_table_irix5, 8000);
return register_binfmt(&irix_format);
}
static void __exit exit_irix_binfmt(void)
{
/*
* Remove the Irix ELF loader.
*/
unregister_binfmt(&irix_format);
}
module_init(init_irix_binfmt)
module_exit(exit_irix_binfmt)
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