tmp_suning_uos_patched/fs/binfmt_som.c
Matthew Wilcox dc02747da7 [PARISC] Fix fs/binfmt_som.c
Fix compilation (missing include of a.out.h)
Fix security hole (need to call unshare_files)

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-10-04 06:51:26 -06:00

322 lines
7.8 KiB
C

/*
* linux/fs/binfmt_som.c
*
* These are the functions used to load SOM format executables as used
* by HP-UX.
*
* Copyright 1999 Matthew Wilcox <willy@bofh.ai>
* based on binfmt_elf which is
* Copyright 1993, 1994: Eric Youngdale (ericy@cais.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/errno.h>
#include <linux/signal.h>
#include <linux/binfmts.h>
#include <linux/som.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/init.h>
#include <asm/a.out.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <linux/elf.h>
static int load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs);
static int load_som_library(struct file *);
/*
* If we don't support core dumping, then supply a NULL so we
* don't even try.
*/
#if 0
static int som_core_dump(long signr, struct pt_regs * regs);
#else
#define som_core_dump NULL
#endif
#define SOM_PAGESTART(_v) ((_v) & ~(unsigned long)(SOM_PAGESIZE-1))
#define SOM_PAGEOFFSET(_v) ((_v) & (SOM_PAGESIZE-1))
#define SOM_PAGEALIGN(_v) (((_v) + SOM_PAGESIZE - 1) & ~(SOM_PAGESIZE - 1))
static struct linux_binfmt som_format = {
.module = THIS_MODULE,
.load_binary = load_som_binary,
.load_shlib = load_som_library,
.core_dump = som_core_dump,
.min_coredump = SOM_PAGESIZE
};
/*
* create_som_tables() parses the env- and arg-strings in new user
* memory and creates the pointer tables from them, and puts their
* addresses on the "stack", returning the new stack pointer value.
*/
static void create_som_tables(struct linux_binprm *bprm)
{
char **argv, **envp;
int argc = bprm->argc;
int envc = bprm->envc;
unsigned long p;
unsigned long *sp;
/* Word-align the stack pointer */
sp = (unsigned long *)((bprm->p + 3) & ~3);
envp = (char **) sp;
sp += envc + 1;
argv = (char **) sp;
sp += argc + 1;
__put_user((unsigned long) envp,++sp);
__put_user((unsigned long) argv,++sp);
__put_user(argc, ++sp);
bprm->p = (unsigned long) sp;
p = current->mm->arg_start;
while (argc-- > 0) {
__put_user((char *)p,argv++);
p += strlen_user((char *)p);
}
__put_user(NULL, argv);
current->mm->arg_end = current->mm->env_start = p;
while (envc-- > 0) {
__put_user((char *)p,envp++);
p += strlen_user((char *)p);
}
__put_user(NULL, envp);
current->mm->env_end = p;
}
static int check_som_header(struct som_hdr *som_ex)
{
int *buf = (int *)som_ex;
int i, ck;
if (som_ex->system_id != SOM_SID_PARISC_1_0 &&
som_ex->system_id != SOM_SID_PARISC_1_1 &&
som_ex->system_id != SOM_SID_PARISC_2_0)
return -ENOEXEC;
if (som_ex->a_magic != SOM_EXEC_NONSHARE &&
som_ex->a_magic != SOM_EXEC_SHARE &&
som_ex->a_magic != SOM_EXEC_DEMAND)
return -ENOEXEC;
if (som_ex->version_id != SOM_ID_OLD &&
som_ex->version_id != SOM_ID_NEW)
return -ENOEXEC;
ck = 0;
for (i=0; i<32; i++)
ck ^= buf[i];
if (ck != 0)
return -ENOEXEC;
return 0;
}
static int map_som_binary(struct file *file,
const struct som_exec_auxhdr *hpuxhdr)
{
unsigned long code_start, code_size, data_start, data_size;
unsigned long bss_start, som_brk;
int retval;
int prot = PROT_READ | PROT_EXEC;
int flags = MAP_FIXED|MAP_PRIVATE|MAP_DENYWRITE|MAP_EXECUTABLE;
mm_segment_t old_fs = get_fs();
set_fs(get_ds());
code_start = SOM_PAGESTART(hpuxhdr->exec_tmem);
code_size = SOM_PAGEALIGN(hpuxhdr->exec_tsize);
current->mm->start_code = code_start;
current->mm->end_code = code_start + code_size;
down_write(&current->mm->mmap_sem);
retval = do_mmap(file, code_start, code_size, prot,
flags, SOM_PAGESTART(hpuxhdr->exec_tfile));
up_write(&current->mm->mmap_sem);
if (retval < 0 && retval > -1024)
goto out;
data_start = SOM_PAGESTART(hpuxhdr->exec_dmem);
data_size = SOM_PAGEALIGN(hpuxhdr->exec_dsize);
current->mm->start_data = data_start;
current->mm->end_data = bss_start = data_start + data_size;
down_write(&current->mm->mmap_sem);
retval = do_mmap(file, data_start, data_size,
prot | PROT_WRITE, flags,
SOM_PAGESTART(hpuxhdr->exec_dfile));
up_write(&current->mm->mmap_sem);
if (retval < 0 && retval > -1024)
goto out;
som_brk = bss_start + SOM_PAGEALIGN(hpuxhdr->exec_bsize);
current->mm->start_brk = current->mm->brk = som_brk;
down_write(&current->mm->mmap_sem);
retval = do_mmap(NULL, bss_start, som_brk - bss_start,
prot | PROT_WRITE, MAP_FIXED | MAP_PRIVATE, 0);
up_write(&current->mm->mmap_sem);
if (retval > 0 || retval < -1024)
retval = 0;
out:
set_fs(old_fs);
return retval;
}
/*
* These are the functions used to load SOM executables and shared
* libraries. There is no binary dependent code anywhere else.
*/
static int
load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs)
{
int som_exec_fileno;
int retval;
unsigned int size;
unsigned long som_entry;
struct som_hdr *som_ex;
struct som_exec_auxhdr *hpuxhdr;
struct files_struct *files;
/* Get the exec-header */
som_ex = (struct som_hdr *) bprm->buf;
retval = check_som_header(som_ex);
if (retval != 0)
goto out;
/* Now read in the auxiliary header information */
retval = -ENOMEM;
size = som_ex->aux_header_size;
if (size > SOM_PAGESIZE)
goto out;
hpuxhdr = kmalloc(size, GFP_KERNEL);
if (!hpuxhdr)
goto out;
retval = kernel_read(bprm->file, som_ex->aux_header_location,
(char *) hpuxhdr, size);
if (retval != size) {
if (retval >= 0)
retval = -EIO;
goto out_free;
}
files = current->files; /* Refcounted so ok */
retval = unshare_files();
if (retval < 0)
goto out_free;
if (files == current->files) {
put_files_struct(files);
files = NULL;
}
retval = get_unused_fd();
if (retval < 0)
goto out_free;
get_file(bprm->file);
fd_install(som_exec_fileno = retval, bprm->file);
/* Flush all traces of the currently running executable */
retval = flush_old_exec(bprm);
if (retval)
goto out_free;
/* OK, This is the point of no return */
current->flags &= ~PF_FORKNOEXEC;
current->personality = PER_HPUX;
/* Set the task size for HP-UX processes such that
* the gateway page is outside the address space.
* This can be fixed later, but for now, this is much
* easier.
*/
current->thread.task_size = 0xc0000000;
/* Set map base to allow enough room for hp-ux heap growth */
current->thread.map_base = 0x80000000;
retval = map_som_binary(bprm->file, hpuxhdr);
if (retval < 0)
goto out_free;
som_entry = hpuxhdr->exec_entry;
kfree(hpuxhdr);
set_binfmt(&som_format);
compute_creds(bprm);
setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
create_som_tables(bprm);
current->mm->start_stack = bprm->p;
#if 0
printk("(start_brk) %08lx\n" , (unsigned long) current->mm->start_brk);
printk("(end_code) %08lx\n" , (unsigned long) current->mm->end_code);
printk("(start_code) %08lx\n" , (unsigned long) current->mm->start_code);
printk("(end_data) %08lx\n" , (unsigned long) current->mm->end_data);
printk("(start_stack) %08lx\n" , (unsigned long) current->mm->start_stack);
printk("(brk) %08lx\n" , (unsigned long) current->mm->brk);
#endif
map_hpux_gateway_page(current,current->mm);
start_thread_som(regs, som_entry, bprm->p);
if (current->ptrace & PT_PTRACED)
send_sig(SIGTRAP, current, 0);
return 0;
/* error cleanup */
out_free:
kfree(hpuxhdr);
out:
return retval;
}
static int load_som_library(struct file *f)
{
/* No lib support in SOM yet. gizza chance.. */
return -ENOEXEC;
}
/* Install the SOM loader.
* N.B. We *rely* on the table being the right size with the
* right number of free slots...
*/
static int __init init_som_binfmt(void)
{
return register_binfmt(&som_format);
}
static void __exit exit_som_binfmt(void)
{
/* Remove the SOM loader. */
unregister_binfmt(&som_format);
}
core_initcall(init_som_binfmt);
module_exit(exit_som_binfmt);