84 static int bprm_creds_from_file(struct linux_binprm *bprm);
131 static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)  in acct_arg_size()  argument
134 	long diff = (long)(pages - bprm->vma_pages);  in acct_arg_size()
139 	bprm->vma_pages = pages;  in acct_arg_size()
143 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,  in get_arg_page()  argument
147 	struct vm_area_struct *vma = bprm->vma;  in get_arg_page()
148 	struct mm_struct *mm = bprm->mm;  in get_arg_page()
171 		acct_arg_size(bprm, vma_pages(vma));  in get_arg_page()
181 static void free_arg_pages(struct linux_binprm *bprm)  in free_arg_pages()  argument
185 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,  in flush_arg_page()  argument
188 	flush_cache_page(bprm->vma, pos, page_to_pfn(page));  in flush_arg_page()
191 static bool valid_arg_len(struct linux_binprm *bprm, long len)  in valid_arg_len()  argument
198 static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)  in acct_arg_size()  argument
202 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,  in get_arg_page()  argument
207 	page = bprm->page[pos / PAGE_SIZE];  in get_arg_page()
212 		bprm->page[pos / PAGE_SIZE] = page;  in get_arg_page()
222 static void free_arg_page(struct linux_binprm *bprm, int i)  in free_arg_page()  argument
224 	if (bprm->page[i]) {  in free_arg_page()
225 		__free_page(bprm->page[i]);  in free_arg_page()
226 		bprm->page[i] = NULL;  in free_arg_page()
230 static void free_arg_pages(struct linux_binprm *bprm)  in free_arg_pages()  argument
235 		free_arg_page(bprm, i);  in free_arg_pages()
238 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,  in flush_arg_page()  argument
243 static bool valid_arg_len(struct linux_binprm *bprm, long len)  in valid_arg_len()  argument
245 	return len <= bprm->p;  in valid_arg_len()
256 static int bprm_mm_init(struct linux_binprm *bprm)  in bprm_mm_init()  argument
261 	bprm->mm = mm = mm_alloc();  in bprm_mm_init()
268 	bprm->rlim_stack = current->signal->rlim[RLIMIT_STACK];  in bprm_mm_init()
272 	bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);  in bprm_mm_init()
274 	err = create_init_stack_vma(bprm->mm, &bprm->vma, &bprm->p);  in bprm_mm_init()
283 		bprm->mm = NULL;  in bprm_mm_init()
369 static inline int bprm_set_stack_limit(struct linux_binprm *bprm,  in bprm_set_stack_limit()  argument
374 	if (bprm->p < limit)  in bprm_set_stack_limit()
376 	bprm->argmin = bprm->p - limit;  in bprm_set_stack_limit()
380 static inline bool bprm_hit_stack_limit(struct linux_binprm *bprm)  in bprm_hit_stack_limit()  argument
383 	return bprm->p < bprm->argmin;  in bprm_hit_stack_limit()
398 static int bprm_stack_limits(struct linux_binprm *bprm)  in bprm_stack_limits()  argument
411 	limit = min(limit, bprm->rlim_stack.rlim_cur / 4);  in bprm_stack_limits()
418 	if (bprm->argc < 0 || bprm->envc < 0)  in bprm_stack_limits()
433 	if (check_add_overflow(max(bprm->argc, 1), bprm->envc, &ptr_size) ||  in bprm_stack_limits()
440 	return bprm_set_stack_limit(bprm, limit);  in bprm_stack_limits()
449 			struct linux_binprm *bprm)  in copy_strings()  argument
471 		if (!valid_arg_len(bprm, len))  in copy_strings()
475 		pos = bprm->p;  in copy_strings()
477 		bprm->p -= len;  in copy_strings()
478 		if (bprm_hit_stack_limit(bprm))  in copy_strings()
506 				page = get_arg_page(bprm, pos, 1);  in copy_strings()
520 				flush_arg_page(bprm, kpos, kmapped_page);  in copy_strings()
541 int copy_string_kernel(const char *arg, struct linux_binprm *bprm)  in copy_string_kernel()  argument
544 	unsigned long pos = bprm->p;  in copy_string_kernel()
548 	if (!valid_arg_len(bprm, len))  in copy_string_kernel()
553 	bprm->p -= len;  in copy_string_kernel()
554 	if (bprm_hit_stack_limit(bprm))  in copy_string_kernel()
566 		page = get_arg_page(bprm, pos, 1);  in copy_string_kernel()
569 		flush_arg_page(bprm, pos & PAGE_MASK, page);  in copy_string_kernel()
579 			       struct linux_binprm *bprm)  in copy_strings_kernel()  argument
582 		int ret = copy_string_kernel(argv[argc], bprm);  in copy_strings_kernel()
598 int setup_arg_pages(struct linux_binprm *bprm,  in setup_arg_pages()  argument
605 	struct vm_area_struct *vma = bprm->vma;  in setup_arg_pages()
617 	stack_base = bprm->rlim_stack.rlim_max;  in setup_arg_pages()
632 	mm->arg_start = bprm->p - stack_shift;  in setup_arg_pages()
633 	bprm->p = vma->vm_end - stack_shift;  in setup_arg_pages()
644 	bprm->p -= stack_shift;  in setup_arg_pages()
645 	mm->arg_start = bprm->p;  in setup_arg_pages()
648 	bprm->exec -= stack_shift;  in setup_arg_pages()
680 			     bprm->file);  in setup_arg_pages()
704 	rlim_stack = bprm->rlim_stack.rlim_cur & PAGE_MASK;  in setup_arg_pages()
713 	current->mm->start_stack = bprm->p;  in setup_arg_pages()
730 int transfer_args_to_stack(struct linux_binprm *bprm,  in transfer_args_to_stack()  argument
736 	stop = bprm->p >> PAGE_SHIFT;  in transfer_args_to_stack()
740 		unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0;  in transfer_args_to_stack()
741 		char *src = kmap_local_page(bprm->page[index]) + offset;  in transfer_args_to_stack()
750 	bprm->exec += *sp_location - MAX_ARG_PAGES * PAGE_SIZE;  in transfer_args_to_stack()
1099 int begin_new_exec(struct linux_binprm * bprm)  in begin_new_exec()  argument
1105 	retval = bprm_creds_from_file(bprm);  in begin_new_exec()
1115 	trace_sched_prepare_exec(current, bprm);  in begin_new_exec()
1120 	bprm->point_of_no_return = true;  in begin_new_exec()
1143 	retval = set_mm_exe_file(bprm->mm, bprm->file);  in begin_new_exec()
1148 	would_dump(bprm, bprm->file);  in begin_new_exec()
1149 	if (bprm->have_execfd)  in begin_new_exec()
1150 		would_dump(bprm, bprm->executable);  in begin_new_exec()
1155 	acct_arg_size(bprm, 0);  in begin_new_exec()
1156 	retval = exec_mmap(bprm->mm);  in begin_new_exec()
1160 	bprm->mm = NULL;  in begin_new_exec()
1184 	me->personality &= ~bprm->per_clear;  in begin_new_exec()
1196 	if (bprm->secureexec) {  in begin_new_exec()
1207 		if (bprm->rlim_stack.rlim_cur > _STK_LIM)  in begin_new_exec()
1208 			bprm->rlim_stack.rlim_cur = _STK_LIM;  in begin_new_exec()
1218 	if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP ||  in begin_new_exec()
1232 	if (bprm->comm_from_dentry) {  in begin_new_exec()
1242 		__set_task_comm(me, smp_load_acquire(&bprm->file->f_path.dentry->d_name.name),  in begin_new_exec()
1246 		__set_task_comm(me, kbasename(bprm->filename), true);  in begin_new_exec()
1254 	retval = set_cred_ucounts(bprm->cred);  in begin_new_exec()
1261 	security_bprm_committing_creds(bprm);  in begin_new_exec()
1263 	commit_creds(bprm->cred);  in begin_new_exec()
1264 	bprm->cred = NULL;  in begin_new_exec()
1279 	security_bprm_committed_creds(bprm);  in begin_new_exec()
1282 	if (bprm->have_execfd) {  in begin_new_exec()
1283 		retval = FD_ADD(0, bprm->executable);  in begin_new_exec()
1286 		bprm->executable = NULL;  in begin_new_exec()
1287 		bprm->execfd = retval;  in begin_new_exec()
1293 	if (!bprm->cred)  in begin_new_exec()
1301 void would_dump(struct linux_binprm *bprm, struct file *file)  in would_dump()  argument
1307 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;  in would_dump()
1310 		user_ns = old = bprm->mm->user_ns;  in would_dump()
1316 			bprm->mm->user_ns = get_user_ns(user_ns);  in would_dump()
1323 void setup_new_exec(struct linux_binprm * bprm)  in setup_new_exec()  argument
1328 	arch_pick_mmap_layout(me->mm, &bprm->rlim_stack);  in setup_new_exec()
1343 void finalize_exec(struct linux_binprm *bprm)  in finalize_exec()  argument
1347 	current->signal->rlim[RLIMIT_STACK] = bprm->rlim_stack;  in finalize_exec()
1358 static int prepare_bprm_creds(struct linux_binprm *bprm)  in prepare_bprm_creds()  argument
1363 	bprm->cred = prepare_exec_creds();  in prepare_bprm_creds()
1364 	if (likely(bprm->cred))  in prepare_bprm_creds()
1380 static void free_bprm(struct linux_binprm *bprm)  in free_bprm()  argument
1382 	if (bprm->mm) {  in free_bprm()
1383 		acct_arg_size(bprm, 0);  in free_bprm()
1384 		mmput(bprm->mm);  in free_bprm()
1386 	free_arg_pages(bprm);  in free_bprm()
1387 	if (bprm->cred) {  in free_bprm()
1391 		abort_creds(bprm->cred);  in free_bprm()
1393 	do_close_execat(bprm->file);  in free_bprm()
1394 	if (bprm->executable)  in free_bprm()
1395 		fput(bprm->executable);  in free_bprm()
1397 	if (bprm->interp != bprm->filename)  in free_bprm()
1398 		kfree(bprm->interp);  in free_bprm()
1399 	kfree(bprm->fdpath);  in free_bprm()
1400 	kfree(bprm);  in free_bprm()
1405 	struct linux_binprm *bprm;  in alloc_bprm()  local
1413 	bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);  in alloc_bprm()
1414 	if (!bprm) {  in alloc_bprm()
1419 	bprm->file = file;  in alloc_bprm()
1422 		bprm->filename = filename->name;  in alloc_bprm()
1425 			bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d", fd);  in alloc_bprm()
1426 			bprm->comm_from_dentry = 1;  in alloc_bprm()
1428 			bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d/%s",  in alloc_bprm()
1431 		if (!bprm->fdpath)  in alloc_bprm()
1444 			bprm->interp_flags |= BINPRM_FLAGS_PATH_INACCESSIBLE;  in alloc_bprm()
1446 		bprm->filename = bprm->fdpath;  in alloc_bprm()
1448 	bprm->interp = bprm->filename;  in alloc_bprm()
1463 	bprm->is_check = !!(flags & AT_EXECVE_CHECK);  in alloc_bprm()
1465 	retval = bprm_mm_init(bprm);  in alloc_bprm()
1467 		return bprm;  in alloc_bprm()
1470 	free_bprm(bprm);  in alloc_bprm()
1474 int bprm_change_interp(const char *interp, struct linux_binprm *bprm)  in bprm_change_interp()  argument
1477 	if (bprm->interp != bprm->filename)  in bprm_change_interp()
1478 		kfree(bprm->interp);  in bprm_change_interp()
1479 	bprm->interp = kstrdup(interp, GFP_KERNEL);  in bprm_change_interp()
1480 	if (!bprm->interp)  in bprm_change_interp()
1491 static void check_unsafe_exec(struct linux_binprm *bprm)  in check_unsafe_exec()  argument
1497 		bprm->unsafe |= LSM_UNSAFE_PTRACE;  in check_unsafe_exec()
1504 		bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS;  in check_unsafe_exec()
1527 		bprm->unsafe |= LSM_UNSAFE_SHARE;  in check_unsafe_exec()
1533 static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)  in bprm_fill_uid()  argument
1570 	if (!vfsuid_has_mapping(bprm->cred->user_ns, vfsuid) ||  in bprm_fill_uid()
1571 	    !vfsgid_has_mapping(bprm->cred->user_ns, vfsgid))  in bprm_fill_uid()
1575 		bprm->per_clear |= PER_CLEAR_ON_SETID;  in bprm_fill_uid()
1576 		bprm->cred->euid = vfsuid_into_kuid(vfsuid);  in bprm_fill_uid()
1580 		bprm->per_clear |= PER_CLEAR_ON_SETID;  in bprm_fill_uid()
1581 		bprm->cred->egid = vfsgid_into_kgid(vfsgid);  in bprm_fill_uid()
1588 static int bprm_creds_from_file(struct linux_binprm *bprm)  in bprm_creds_from_file()  argument
1591 	struct file *file = bprm->execfd_creds ? bprm->executable : bprm->file;  in bprm_creds_from_file()
1593 	bprm_fill_uid(bprm, file);  in bprm_creds_from_file()
1594 	return security_bprm_creds_from_file(bprm, file);  in bprm_creds_from_file()
1603 static int prepare_binprm(struct linux_binprm *bprm)  in prepare_binprm()  argument
1607 	memset(bprm->buf, 0, BINPRM_BUF_SIZE);  in prepare_binprm()
1608 	return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos);  in prepare_binprm()
1616 int remove_arg_zero(struct linux_binprm *bprm)  in remove_arg_zero()  argument
1622 	if (!bprm->argc)  in remove_arg_zero()
1626 		offset = bprm->p & ~PAGE_MASK;  in remove_arg_zero()
1627 		page = get_arg_page(bprm, bprm->p, 0);  in remove_arg_zero()
1633 				offset++, bprm->p++)  in remove_arg_zero()
1640 	bprm->p++;  in remove_arg_zero()
1641 	bprm->argc--;  in remove_arg_zero()
1650 static int search_binary_handler(struct linux_binprm *bprm)  in search_binary_handler()  argument
1655 	retval = prepare_binprm(bprm);  in search_binary_handler()
1659 	retval = security_bprm_check(bprm);  in search_binary_handler()
1669 		retval = fmt->load_binary(bprm);  in search_binary_handler()
1673 		if (bprm->point_of_no_return || (retval != -ENOEXEC)) {  in search_binary_handler()
1684 static int exec_binprm(struct linux_binprm *bprm)  in exec_binprm()  argument
1701 		ret = search_binary_handler(bprm);  in exec_binprm()
1704 		if (!bprm->interpreter)  in exec_binprm()
1707 		exec = bprm->file;  in exec_binprm()
1708 		bprm->file = bprm->interpreter;  in exec_binprm()
1709 		bprm->interpreter = NULL;  in exec_binprm()
1712 		if (unlikely(bprm->have_execfd)) {  in exec_binprm()
1713 			if (bprm->executable) {  in exec_binprm()
1717 			bprm->executable = exec;  in exec_binprm()
1722 	audit_bprm(bprm);  in exec_binprm()
1723 	trace_sched_process_exec(current, old_pid, bprm);  in exec_binprm()
1729 static int bprm_execve(struct linux_binprm *bprm)  in bprm_execve()  argument
1733 	retval = prepare_bprm_creds(bprm);  in bprm_execve()
1742 	check_unsafe_exec(bprm);  in bprm_execve()
1749 	retval = security_bprm_creds_for_exec(bprm);  in bprm_execve()
1750 	if (retval || bprm->is_check)  in bprm_execve()
1753 	retval = exec_binprm(bprm);  in bprm_execve()
1773 	if (bprm->point_of_no_return && !fatal_signal_pending(current))  in bprm_execve()
1788 	struct linux_binprm *bprm;  in do_execveat_common()  local
1810 	bprm = alloc_bprm(fd, filename, flags);  in do_execveat_common()
1811 	if (IS_ERR(bprm)) {  in do_execveat_common()
1812 		retval = PTR_ERR(bprm);  in do_execveat_common()
1819 	bprm->argc = retval;  in do_execveat_common()
1824 	bprm->envc = retval;  in do_execveat_common()
1826 	retval = bprm_stack_limits(bprm);  in do_execveat_common()
1830 	retval = copy_string_kernel(bprm->filename, bprm);  in do_execveat_common()
1833 	bprm->exec = bprm->p;  in do_execveat_common()
1835 	retval = copy_strings(bprm->envc, envp, bprm);  in do_execveat_common()
1839 	retval = copy_strings(bprm->argc, argv, bprm);  in do_execveat_common()
1849 	if (bprm->argc == 0) {  in do_execveat_common()
1850 		retval = copy_string_kernel("", bprm);  in do_execveat_common()
1853 		bprm->argc = 1;  in do_execveat_common()
1856 			     current->comm, bprm->filename);  in do_execveat_common()
1859 	retval = bprm_execve(bprm);  in do_execveat_common()
1861 	free_bprm(bprm);  in do_execveat_common()
1872 	struct linux_binprm *bprm;  in kernel_execve()  local
1884 	bprm = alloc_bprm(fd, filename, 0);  in kernel_execve()
1885 	if (IS_ERR(bprm)) {  in kernel_execve()
1886 		retval = PTR_ERR(bprm);  in kernel_execve()
1895 	bprm->argc = retval;  in kernel_execve()
1900 	bprm->envc = retval;  in kernel_execve()
1902 	retval = bprm_stack_limits(bprm);  in kernel_execve()
1906 	retval = copy_string_kernel(bprm->filename, bprm);  in kernel_execve()
1909 	bprm->exec = bprm->p;  in kernel_execve()
1911 	retval = copy_strings_kernel(bprm->envc, envp, bprm);  in kernel_execve()
1915 	retval = copy_strings_kernel(bprm->argc, argv, bprm);  in kernel_execve()
1919 	retval = bprm_execve(bprm);  in kernel_execve()
1921 	free_bprm(bprm);  in kernel_execve()