int __set_personality(unsigned int personality)
{
struct exec_domain *oep = current_thread_info()->exec_domain;
current_thread_info()->exec_domain = lookup_exec_domain(personality);
current->personality = personality;
module_put(oep->module);
return 0;
}
int
__set_personality(u_long personality)
{
struct exec_domain *ep, *oep;
ep = lookup_exec_domain(personality);
if(!ep)
return -ENOEXEC;
/* if the needed exec domain is already set for this process
then we save the works for registering with the new fs
and releasing the old fs and exec_domain,
we just have to update the personality to this process */
if (ep == current_thread_info()->exec_domain) {
current->personality = personality;
return 0;
}
/* when the new fs is already bound to the current process */
if (atomic_read(¤t->fs->count) != 1) {
struct fs_struct *fsp, *ofsp;
/* register as client for the new fs by copying it */
fsp = copy_fs_struct(current->fs);
if (fsp == NULL) {
module_put(ep->module);
return -ENOMEM;
}
/* replace the old with the new fs */
task_lock(current);
ofsp = current->fs;
current->fs = fsp;
task_unlock(current);
/* quit as a client to the old fs */
put_fs_struct(ofsp);
}
/*
* At that point we are guaranteed to be the sole owner of
* current->fs.
*/
/* replace the old with the new exec_domain */
current->personality = personality;
oep = current_thread_info()->exec_domain;
current_thread_info()->exec_domain = ep;
set_fs_altroot();
/* quit as client for the old exec_domain */
module_put(oep->module);
return 0;
}
int
__set_personality(u_long personality)
{
struct exec_domain *ep, *oep;
ep = lookup_exec_domain(personality);
if (ep == current_thread_info()->exec_domain) {
current->personality = personality;
module_put(ep->module);
return 0;
}
current->personality = personality;
oep = current_thread_info()->exec_domain;
current_thread_info()->exec_domain = ep;
module_put(oep->module);
return 0;
}
int
__set_personality(u_long personality)
{
struct exec_domain *ep, *oep;
ep = lookup_exec_domain(personality);
if (ep == current_thread_info()->exec_domain) {
current->personality = personality;
return 0;
}
if (atomic_read(¤t->fs->count) != 1) {
struct fs_struct *fsp, *ofsp;
fsp = copy_fs_struct(current->fs);
if (fsp == NULL) {
module_put(ep->module);
return -ENOMEM;
}
task_lock(current);
ofsp = current->fs;
current->fs = fsp;
task_unlock(current);
put_fs_struct(ofsp);
}
/*
* At that point we are guaranteed to be the sole owner of
* current->fs.
*/
current->personality = personality;
oep = current_thread_info()->exec_domain;
current_thread_info()->exec_domain = ep;
set_fs_altroot();
module_put(oep->module);
return 0;
}
asmlinkage int sys_personality(unsigned long personality) {
struct exec_domain *it;
unsigned long old_personality;
if (personality == 0xffffffff)
return current->personality;
it = lookup_exec_domain(personality);
if (!it)
return -EINVAL;
old_personality = current->personality;
if (current->exec_domain && current->exec_domain->use_count)
(*current->exec_domain->use_count)--;
current->personality = personality;
current->exec_domain = it;
if (current->exec_domain->use_count)
(*current->exec_domain->use_count)++;
return old_personality;
}
static inline int
do_load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs)
{
struct file * file;
struct dentry *interpreter_dentry = NULL; /* to shut gcc up */
unsigned long load_addr = 0, load_bias;
int load_addr_set = 0;
char * elf_interpreter = NULL;
unsigned int interpreter_type = INTERPRETER_NONE;
unsigned char ibcs2_interpreter = 0;
mm_segment_t old_fs;
unsigned long error;
struct elf_phdr * elf_ppnt, *elf_phdata;
unsigned long elf_bss, k, elf_brk;
int elf_exec_fileno;
int retval, size, i;
unsigned long elf_entry, interp_load_addr = 0;
unsigned long start_code, end_code, end_data;
struct elfhdr elf_ex;
struct elfhdr interp_elf_ex;
struct exec interp_ex;
char passed_fileno[6];
/* Get the exec-header */
elf_ex = *((struct elfhdr *) bprm->buf);
retval = -ENOEXEC;
/* First of all, some simple consistency checks */
if (elf_ex.e_ident[0] != 0x7f ||
strncmp(&elf_ex.e_ident[1], "ELF", 3) != 0)
goto out;
if (elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN)
goto out;
if (!elf_check_arch(elf_ex.e_machine))
goto out;
#ifdef __mips__
/* allow only mips1 if exec is MIPSEB elf,
because IRIX binaries handled elsewhere. */
/* borrowed from binutils/include/elf/common.h*/
#define EI_DATA 5 /* Data encoding */
#define ELFDATA2MSB 2 /* 2's complement, big endian */
if ((elf_ex.e_ident[EI_DATA] == ELFDATA2MSB ) &&
(elf_ex.e_flags & EF_MIPS_ARCH) ) {
retval = -ENOEXEC;
goto out;
}
#endif
if (!bprm->dentry->d_inode->i_op ||
!bprm->dentry->d_inode->i_op->default_file_ops ||
!bprm->dentry->d_inode->i_op->default_file_ops->mmap)
goto out;
/* Now read in all of the header information */
retval = -ENOMEM;
size = elf_ex.e_phentsize * elf_ex.e_phnum;
elf_phdata = (struct elf_phdr *) kmalloc(size, GFP_KERNEL);
if (!elf_phdata)
goto out;
retval = read_exec(bprm->dentry, elf_ex.e_phoff,
(char *) elf_phdata, size, 1);
if (retval < 0)
goto out_free_ph;
retval = open_dentry(bprm->dentry, O_RDONLY);
if (retval < 0)
goto out_free_ph;
elf_exec_fileno = retval;
file = fget(elf_exec_fileno);
elf_ppnt = elf_phdata;
elf_bss = 0;
elf_brk = 0;
start_code = ~0UL;
end_code = 0;
end_data = 0;
for (i = 0; i < elf_ex.e_phnum; i++) {
if (elf_ppnt->p_type == PT_INTERP) {
retval = -EINVAL;
if (elf_interpreter)
goto out_free_interp;
/* This is the program interpreter used for
* shared libraries - for now assume that this
* is an a.out format binary
*/
retval = -ENOMEM;
elf_interpreter = (char *) kmalloc(elf_ppnt->p_filesz,
GFP_KERNEL);
if (!elf_interpreter)
goto out_free_file;
retval = read_exec(bprm->dentry, elf_ppnt->p_offset,
elf_interpreter,
elf_ppnt->p_filesz, 1);
if (retval < 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;
#if 0
printk("Using ELF interpreter %s\n", elf_interpreter);
#endif
old_fs = get_fs(); /* This could probably be optimized */
set_fs(get_ds());
#ifdef __sparc__
if (ibcs2_interpreter) {
unsigned long old_pers = current->personality;
current->personality = PER_SVR4;
interpreter_dentry = open_namei(elf_interpreter,
0, 0);
current->personality = old_pers;
} else
#endif
interpreter_dentry = open_namei(elf_interpreter,
0, 0);
set_fs(old_fs);
retval = PTR_ERR(interpreter_dentry);
if (IS_ERR(interpreter_dentry))
goto out_free_interp;
retval = permission(interpreter_dentry->d_inode, MAY_EXEC);
if (retval < 0)
goto out_free_dentry;
retval = read_exec(interpreter_dentry, 0, bprm->buf, 128, 1);
if (retval < 0)
goto out_free_dentry;
/* Get the exec headers */
interp_ex = *((struct exec *) bprm->buf);
interp_elf_ex = *((struct elfhdr *) bprm->buf);
}
elf_ppnt++;
}
/* 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(interp_ex) != OMAGIC) &&
(N_MAGIC(interp_ex) != ZMAGIC) &&
(N_MAGIC(interp_ex) != QMAGIC))
interpreter_type = INTERPRETER_ELF;
if (interp_elf_ex.e_ident[0] != 0x7f ||
strncmp(&interp_elf_ex.e_ident[1], "ELF", 3) != 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) {
printk(KERN_WARNING "ELF: Ambiguous type, using ELF\n");
interpreter_type = INTERPRETER_ELF;
}
}
/* OK, we are done with that, now set up the arg stuff,
and then start this sucker up */
if (!bprm->sh_bang) {
char * passed_p;
if (interpreter_type == INTERPRETER_AOUT) {
sprintf(passed_fileno, "%d", elf_exec_fileno);
passed_p = passed_fileno;
if (elf_interpreter) {
bprm->p = copy_strings(1,&passed_p,bprm->page,bprm->p,2);
bprm->argc++;
}
}
retval = -E2BIG;
if (!bprm->p)
goto out_free_dentry;
}
/* 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 long) elf_ex.e_entry;
/* Do this immediately, since STACK_TOP as used in setup_arg_pages
may depend on the personality. */
SET_PERSONALITY(elf_ex, ibcs2_interpreter);
/* Do this so that we can load the interpreter, if need be. We will
change some of these later */
current->mm->rss = 0;
bprm->p = setup_arg_pages(bprm->p, bprm);
current->mm->start_stack = bprm->p;
/* 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_ex.e_type==ET_DYN ? ELF_ET_DYN_BASE : 0);
/* 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. */
old_fs = get_fs();
set_fs(get_ds());
for(i = 0, elf_ppnt = elf_phdata; i < elf_ex.e_phnum; i++, elf_ppnt++) {
int elf_prot = 0, elf_flags;
unsigned long vaddr;
if (elf_ppnt->p_type != PT_LOAD)
continue;
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 (elf_ex.e_type == ET_EXEC || load_addr_set) {
elf_flags |= MAP_FIXED;
}
error = do_mmap(file, ELF_PAGESTART(load_bias + vaddr),
(elf_ppnt->p_filesz +
ELF_PAGEOFFSET(elf_ppnt->p_vaddr)),
elf_prot, elf_flags, (elf_ppnt->p_offset -
ELF_PAGEOFFSET(elf_ppnt->p_vaddr)));
if (!load_addr_set) {
load_addr_set = 1;
load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
if (elf_ex.e_type == ET_DYN) {
load_bias += error -
ELF_PAGESTART(load_bias + vaddr);
load_addr += error;
}
}
k = elf_ppnt->p_vaddr;
if (k < start_code) start_code = k;
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;
}
set_fs(old_fs);
fput(file); /* all done with the file */
elf_entry += load_bias;
elf_bss += load_bias;
elf_brk += load_bias;
start_code += load_bias;
end_code += load_bias;
end_data += load_bias;
if (elf_interpreter) {
if (interpreter_type == INTERPRETER_AOUT)
elf_entry = load_aout_interp(&interp_ex,
interpreter_dentry);
else
elf_entry = load_elf_interp(&interp_elf_ex,
interpreter_dentry,
&interp_load_addr);
dput(interpreter_dentry);
kfree(elf_interpreter);
if (elf_entry == ~0UL) {
printk(KERN_ERR "Unable to load interpreter\n");
kfree(elf_phdata);
send_sig(SIGSEGV, current, 0);
return 0;
}
}
kfree(elf_phdata);
if (interpreter_type != INTERPRETER_AOUT)
sys_close(elf_exec_fileno);
if (current->exec_domain && current->exec_domain->module)
__MOD_DEC_USE_COUNT(current->exec_domain->module);
if (current->binfmt && current->binfmt->module)
__MOD_DEC_USE_COUNT(current->binfmt->module);
current->exec_domain = lookup_exec_domain(current->personality);
current->binfmt = &elf_format;
if (current->exec_domain && current->exec_domain->module)
__MOD_INC_USE_COUNT(current->exec_domain->module);
if (current->binfmt && current->binfmt->module)
__MOD_INC_USE_COUNT(current->binfmt->module);
#ifndef VM_STACK_FLAGS
current->executable = dget(bprm->dentry);
#endif
compute_creds(bprm);
current->flags &= ~PF_FORKNOEXEC;
bprm->p = (unsigned long)
create_elf_tables((char *)bprm->p,
bprm->argc,
bprm->envc,
(interpreter_type == INTERPRETER_ELF ? &elf_ex : NULL),
load_addr, load_bias,
interp_load_addr,
(interpreter_type == INTERPRETER_AOUT ? 0 : 1));
/* N.B. passed_fileno might not be initialized? */
if (interpreter_type == INTERPRETER_AOUT)
current->mm->arg_start += strlen(passed_fileno) + 1;
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);
padzero(elf_bss);
#if 0
printk("(start_brk) %x\n" , current->mm->start_brk);
printk("(end_code) %x\n" , current->mm->end_code);
printk("(start_code) %x\n" , current->mm->start_code);
printk("(end_data) %x\n" , current->mm->end_data);
printk("(start_stack) %x\n" , current->mm->start_stack);
printk("(brk) %x\n" , current->mm->brk);
#endif
if ( current->personality == PER_SVR4 )
{
/* 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. */
/* N.B. Shouldn't the size here be PAGE_SIZE?? */
error = do_mmap(NULL, 0, 4096, PROT_READ | PROT_EXEC,
MAP_FIXED | MAP_PRIVATE, 0);
}
#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. This macro performs whatever initialization to
* the regs structure is required.
*/
ELF_PLAT_INIT(regs);
#endif
start_thread(regs, elf_entry, bprm->p);
if (current->flags & PF_PTRACED)
send_sig(SIGTRAP, current, 0);
retval = 0;
out:
return retval;
/* error cleanup */
out_free_dentry:
dput(interpreter_dentry);
out_free_interp:
if (elf_interpreter)
kfree(elf_interpreter);
out_free_file:
fput(file);
sys_close(elf_exec_fileno);
out_free_ph:
kfree(elf_phdata);
goto out;
}
static inline int
do_load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
{
struct exec ex;
struct file * file;
int fd;
unsigned long error;
unsigned long p = bprm->p;
unsigned long fd_offset;
unsigned long rlim;
ex = *((struct exec *) bprm->buf); /* exec-header */
if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
N_MAGIC(ex) != QMAGIC) ||
N_TRSIZE(ex) || N_DRSIZE(ex) ||
bprm->inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
return -ENOEXEC;
}
current->personality = PER_LINUX;
fd_offset = N_TXTOFF(ex);
#if defined (__i386__) || defined (CONFIG_ARM)
if (N_MAGIC(ex) == ZMAGIC && fd_offset != BLOCK_SIZE) {
printk(KERN_NOTICE "N_TXTOFF != BLOCK_SIZE. See a.out.h.\n");
return -ENOEXEC;
}
if (N_MAGIC(ex) == ZMAGIC && ex.a_text &&
(fd_offset < bprm->inode->i_sb->s_blocksize)) {
printk(KERN_NOTICE "N_TXTOFF < BLOCK_SIZE. Please convert binary.\n");
return -ENOEXEC;
}
#endif
#if defined(CONFIG_ARM)
if (N_MACHTYPE(ex) != M_ARM) {
printk(KERN_NOTICE "Binary != ARM. Please recompile binary.\n");
return -ENOEXEC;
}
#endif
/* Check initial limits. This avoids letting people circumvent
* size limits imposed on them by creating programs with large
* arrays in the data or bss.
*/
rlim = current->rlim[RLIMIT_DATA].rlim_cur;
if (rlim >= RLIM_INFINITY)
rlim = ~0;
if (ex.a_data + ex.a_bss > rlim)
return -ENOMEM;
if (flush_old_exec(bprm))
return -ENOMEM;
/* OK, This is the point of no return */
current->mm->end_code = ex.a_text +
(current->mm->start_code = N_TXTADDR(ex));
current->mm->end_data = ex.a_data +
(current->mm->start_data = N_DATADDR(ex));
current->mm->brk = ex.a_bss +
(current->mm->start_brk = N_BSSADDR(ex));
current->mm->rss = 0;
current->mm->mmap = NULL;
current->suid = current->euid = current->fsuid = bprm->e_uid;
current->sgid = current->egid = current->fsgid = bprm->e_gid;
current->flags &= ~PF_FORKNOEXEC;
if (N_MAGIC(ex) == OMAGIC) {
#if defined(__alpha__) || defined(CONFIG_ARM)
#ifndef CONFIG_ARM
do_mmap(NULL, N_TXTADDR(ex) & PAGE_MASK,
ex.a_text+ex.a_data + PAGE_SIZE - 1,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_FIXED|MAP_PRIVATE, 0);
#else
do_mmap(NULL, N_TXTADDR(ex),
ex.a_text+ex.a_data,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_FIXED|MAP_PRIVATE, 0);
#endif
read_exec(bprm->inode, fd_offset, (char *) N_TXTADDR(ex),
ex.a_text+ex.a_data, 0);
#else
do_mmap(NULL, 0, ex.a_text+ex.a_data,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_FIXED|MAP_PRIVATE, 0);
read_exec(bprm->inode, 32, (char *) 0, ex.a_text+ex.a_data, 0);
#endif
} else {
if (ex.a_text & 0xfff || ex.a_data & 0xfff)
printk(KERN_NOTICE "executable not page aligned\n");
fd = open_inode(bprm->inode, O_RDONLY);
if (fd < 0) {
send_sig(SIGKILL, current, 0);
return fd;
}
file = current->files->fd[fd];
if (!file->f_op || !file->f_op->mmap) {
sys_close(fd);
do_mmap(NULL, 0, ex.a_text+ex.a_data,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_FIXED|MAP_PRIVATE, 0);
read_exec(bprm->inode, fd_offset,
(char *) N_TXTADDR(ex), ex.a_text+ex.a_data, 0);
goto beyond_if;
}
error = do_mmap(file, N_TXTADDR(ex), ex.a_text,
PROT_READ | PROT_EXEC,
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
fd_offset);
if (error != N_TXTADDR(ex)) {
sys_close(fd);
send_sig(SIGKILL, current, 0);
return error;
}
error = do_mmap(file, N_DATADDR(ex), ex.a_data,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
fd_offset + ex.a_text);
sys_close(fd);
if (error != N_DATADDR(ex)) {
send_sig(SIGKILL, current, 0);
return error;
}
}
beyond_if:
if (current->exec_domain && current->exec_domain->use_count)
(*current->exec_domain->use_count)--;
if (current->binfmt && current->binfmt->use_count)
(*current->binfmt->use_count)--;
current->exec_domain = lookup_exec_domain(current->personality);
current->binfmt = &aout_format;
if (current->exec_domain && current->exec_domain->use_count)
(*current->exec_domain->use_count)++;
if (current->binfmt && current->binfmt->use_count)
(*current->binfmt->use_count)++;
set_brk(current->mm->start_brk, current->mm->brk);
p = setup_arg_pages(p, bprm);
p = (unsigned long) create_aout_tables((char *)p, bprm);
current->mm->start_stack = p;
#ifdef __alpha__
regs->gp = ex.a_gpvalue;
#endif
start_thread(regs, ex.a_entry, p);
if (current->flags & PF_PTRACED)
send_sig(SIGTRAP, current, 0);
#ifndef CONFIG_ARM
return 0;
#else
return regs->ARM_r0;
#endif
}
