79 static int bprm_creds_from_file(struct linux_binprm *bprm);
185 static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)  in acct_arg_size()  argument
188 	long diff = (long)(pages - bprm->vma_pages);  in acct_arg_size()
193 	bprm->vma_pages = pages;  in acct_arg_size()
197 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,  in get_arg_page()  argument
201 	struct vm_area_struct *vma = bprm->vma;  in get_arg_page()
202 	struct mm_struct *mm = bprm->mm;  in get_arg_page()
233 		acct_arg_size(bprm, vma_pages(vma));  in get_arg_page()
243 static void free_arg_pages(struct linux_binprm *bprm)  in free_arg_pages()  argument
247 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,  in flush_arg_page()  argument
250 	flush_cache_page(bprm->vma, pos, page_to_pfn(page));  in flush_arg_page()
253 static int __bprm_mm_init(struct linux_binprm *bprm)  in __bprm_mm_init()  argument
257 	struct mm_struct *mm = bprm->mm;  in __bprm_mm_init()
259 	bprm->vma = vma = vm_area_alloc(mm);  in __bprm_mm_init()
287 	bprm->p = vma->vm_end - sizeof(void *);  in __bprm_mm_init()
292 	bprm->vma = NULL;  in __bprm_mm_init()
297 static bool valid_arg_len(struct linux_binprm *bprm, long len)  in valid_arg_len()  argument
304 static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages)  in acct_arg_size()  argument
308 static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,  in get_arg_page()  argument
313 	page = bprm->page[pos / PAGE_SIZE];  in get_arg_page()
318 		bprm->page[pos / PAGE_SIZE] = page;  in get_arg_page()
328 static void free_arg_page(struct linux_binprm *bprm, int i)  in free_arg_page()  argument
330 	if (bprm->page[i]) {  in free_arg_page()
331 		__free_page(bprm->page[i]);  in free_arg_page()
332 		bprm->page[i] = NULL;  in free_arg_page()
336 static void free_arg_pages(struct linux_binprm *bprm)  in free_arg_pages()  argument
341 		free_arg_page(bprm, i);  in free_arg_pages()
344 static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos,  in flush_arg_page()  argument
349 static int __bprm_mm_init(struct linux_binprm *bprm)  in __bprm_mm_init()  argument
351 	bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *);  in __bprm_mm_init()
355 static bool valid_arg_len(struct linux_binprm *bprm, long len)  in valid_arg_len()  argument
357 	return len <= bprm->p;  in valid_arg_len()
368 static int bprm_mm_init(struct linux_binprm *bprm)  in bprm_mm_init()  argument
373 	bprm->mm = mm = mm_alloc();  in bprm_mm_init()
380 	bprm->rlim_stack = current->signal->rlim[RLIMIT_STACK];  in bprm_mm_init()
383 	err = __bprm_mm_init(bprm);  in bprm_mm_init()
391 		bprm->mm = NULL;  in bprm_mm_init()
477 static int bprm_stack_limits(struct linux_binprm *bprm)  in bprm_stack_limits()  argument
490 	limit = min(limit, bprm->rlim_stack.rlim_cur / 4);  in bprm_stack_limits()
509 	ptr_size = (max(bprm->argc, 1) + bprm->envc) * sizeof(void *);  in bprm_stack_limits()
514 	bprm->argmin = bprm->p - limit;  in bprm_stack_limits()
524 			struct linux_binprm *bprm)  in copy_strings()  argument
546 		if (!valid_arg_len(bprm, len))  in copy_strings()
550 		pos = bprm->p;  in copy_strings()
552 		bprm->p -= len;  in copy_strings()
554 		if (bprm->p < bprm->argmin)  in copy_strings()
583 				page = get_arg_page(bprm, pos, 1);  in copy_strings()
597 				flush_arg_page(bprm, kpos, kmapped_page);  in copy_strings()
618 int copy_string_kernel(const char *arg, struct linux_binprm *bprm)  in copy_string_kernel()  argument
621 	unsigned long pos = bprm->p;  in copy_string_kernel()
625 	if (!valid_arg_len(bprm, len))  in copy_string_kernel()
630 	bprm->p -= len;  in copy_string_kernel()
631 	if (IS_ENABLED(CONFIG_MMU) && bprm->p < bprm->argmin)  in copy_string_kernel()
643 		page = get_arg_page(bprm, pos, 1);  in copy_string_kernel()
646 		flush_arg_page(bprm, pos & PAGE_MASK, page);  in copy_string_kernel()
656 			       struct linux_binprm *bprm)  in copy_strings_kernel()  argument
659 		int ret = copy_string_kernel(argv[argc], bprm);  in copy_strings_kernel()
749 int setup_arg_pages(struct linux_binprm *bprm,  in setup_arg_pages()  argument
756 	struct vm_area_struct *vma = bprm->vma;  in setup_arg_pages()
768 	stack_base = bprm->rlim_stack.rlim_max;  in setup_arg_pages()
782 	mm->arg_start = bprm->p - stack_shift;  in setup_arg_pages()
783 	bprm->p = vma->vm_end - stack_shift;  in setup_arg_pages()
794 	bprm->p -= stack_shift;  in setup_arg_pages()
795 	mm->arg_start = bprm->p;  in setup_arg_pages()
798 	if (bprm->loader)  in setup_arg_pages()
799 		bprm->loader -= stack_shift;  in setup_arg_pages()
800 	bprm->exec -= stack_shift;  in setup_arg_pages()
832 			     bprm->file);  in setup_arg_pages()
851 	rlim_stack = bprm->rlim_stack.rlim_cur & PAGE_MASK;  in setup_arg_pages()
860 	current->mm->start_stack = bprm->p;  in setup_arg_pages()
877 int transfer_args_to_stack(struct linux_binprm *bprm,  in transfer_args_to_stack()  argument
883 	stop = bprm->p >> PAGE_SHIFT;  in transfer_args_to_stack()
887 		unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0;  in transfer_args_to_stack()
888 		char *src = kmap_local_page(bprm->page[index]) + offset;  in transfer_args_to_stack()
1246 int begin_new_exec(struct linux_binprm * bprm)  in begin_new_exec()  argument
1252 	retval = bprm_creds_from_file(bprm);  in begin_new_exec()
1259 	bprm->point_of_no_return = true;  in begin_new_exec()
1283 	retval = set_mm_exe_file(bprm->mm, bprm->file);  in begin_new_exec()
1288 	would_dump(bprm, bprm->file);  in begin_new_exec()
1289 	if (bprm->have_execfd)  in begin_new_exec()
1290 		would_dump(bprm, bprm->executable);  in begin_new_exec()
1295 	acct_arg_size(bprm, 0);  in begin_new_exec()
1296 	retval = exec_mmap(bprm->mm);  in begin_new_exec()
1300 	bprm->mm = NULL;  in begin_new_exec()
1324 	me->personality &= ~bprm->per_clear;  in begin_new_exec()
1336 	if (bprm->secureexec) {  in begin_new_exec()
1347 		if (bprm->rlim_stack.rlim_cur > _STK_LIM)  in begin_new_exec()
1348 			bprm->rlim_stack.rlim_cur = _STK_LIM;  in begin_new_exec()
1358 	if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP ||  in begin_new_exec()
1366 	__set_task_comm(me, kbasename(bprm->filename), true);  in begin_new_exec()
1373 	retval = set_cred_ucounts(bprm->cred);  in begin_new_exec()
1380 	security_bprm_committing_creds(bprm);  in begin_new_exec()
1382 	commit_creds(bprm->cred);  in begin_new_exec()
1383 	bprm->cred = NULL;  in begin_new_exec()
1398 	security_bprm_committed_creds(bprm);  in begin_new_exec()
1401 	if (bprm->have_execfd) {  in begin_new_exec()
1405 		fd_install(retval, bprm->executable);  in begin_new_exec()
1406 		bprm->executable = NULL;  in begin_new_exec()
1407 		bprm->execfd = retval;  in begin_new_exec()
1413 	if (!bprm->cred)  in begin_new_exec()
1421 void would_dump(struct linux_binprm *bprm, struct file *file)  in would_dump()  argument
1427 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;  in would_dump()
1430 		user_ns = old = bprm->mm->user_ns;  in would_dump()
1436 			bprm->mm->user_ns = get_user_ns(user_ns);  in would_dump()
1443 void setup_new_exec(struct linux_binprm * bprm)  in setup_new_exec()  argument
1448 	arch_pick_mmap_layout(me->mm, &bprm->rlim_stack);  in setup_new_exec()
1463 void finalize_exec(struct linux_binprm *bprm)  in finalize_exec()  argument
1467 	current->signal->rlim[RLIMIT_STACK] = bprm->rlim_stack;  in finalize_exec()
1478 static int prepare_bprm_creds(struct linux_binprm *bprm)  in prepare_bprm_creds()  argument
1483 	bprm->cred = prepare_exec_creds();  in prepare_bprm_creds()
1484 	if (likely(bprm->cred))  in prepare_bprm_creds()
1491 static void free_bprm(struct linux_binprm *bprm)  in free_bprm()  argument
1493 	if (bprm->mm) {  in free_bprm()
1494 		acct_arg_size(bprm, 0);  in free_bprm()
1495 		mmput(bprm->mm);  in free_bprm()
1497 	free_arg_pages(bprm);  in free_bprm()
1498 	if (bprm->cred) {  in free_bprm()
1500 		abort_creds(bprm->cred);  in free_bprm()
1502 	if (bprm->file) {  in free_bprm()
1503 		allow_write_access(bprm->file);  in free_bprm()
1504 		fput(bprm->file);  in free_bprm()
1506 	if (bprm->executable)  in free_bprm()
1507 		fput(bprm->executable);  in free_bprm()
1509 	if (bprm->interp != bprm->filename)  in free_bprm()
1510 		kfree(bprm->interp);  in free_bprm()
1511 	kfree(bprm->fdpath);  in free_bprm()
1512 	kfree(bprm);  in free_bprm()
1517 	struct linux_binprm *bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);  in alloc_bprm()  local
1519 	if (!bprm)  in alloc_bprm()
1523 		bprm->filename = filename->name;  in alloc_bprm()
1526 			bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d", fd);  in alloc_bprm()
1528 			bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d/%s",  in alloc_bprm()
1530 		if (!bprm->fdpath)  in alloc_bprm()
1533 		bprm->filename = bprm->fdpath;  in alloc_bprm()
1535 	bprm->interp = bprm->filename;  in alloc_bprm()
1537 	retval = bprm_mm_init(bprm);  in alloc_bprm()
1540 	return bprm;  in alloc_bprm()
1543 	free_bprm(bprm);  in alloc_bprm()
1548 int bprm_change_interp(const char *interp, struct linux_binprm *bprm)  in bprm_change_interp()  argument
1551 	if (bprm->interp != bprm->filename)  in bprm_change_interp()
1552 		kfree(bprm->interp);  in bprm_change_interp()
1553 	bprm->interp = kstrdup(interp, GFP_KERNEL);  in bprm_change_interp()
1554 	if (!bprm->interp)  in bprm_change_interp()
1565 static void check_unsafe_exec(struct linux_binprm *bprm)  in check_unsafe_exec()  argument
1571 		bprm->unsafe |= LSM_UNSAFE_PTRACE;  in check_unsafe_exec()
1578 		bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS;  in check_unsafe_exec()
1597 		bprm->unsafe |= LSM_UNSAFE_SHARE;  in check_unsafe_exec()
1603 static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)  in bprm_fill_uid()  argument
1634 	if (!vfsuid_has_mapping(bprm->cred->user_ns, vfsuid) ||  in bprm_fill_uid()
1635 	    !vfsgid_has_mapping(bprm->cred->user_ns, vfsgid))  in bprm_fill_uid()
1639 		bprm->per_clear |= PER_CLEAR_ON_SETID;  in bprm_fill_uid()
1640 		bprm->cred->euid = vfsuid_into_kuid(vfsuid);  in bprm_fill_uid()
1644 		bprm->per_clear |= PER_CLEAR_ON_SETID;  in bprm_fill_uid()
1645 		bprm->cred->egid = vfsgid_into_kgid(vfsgid);  in bprm_fill_uid()
1652 static int bprm_creds_from_file(struct linux_binprm *bprm)  in bprm_creds_from_file()  argument
1655 	struct file *file = bprm->execfd_creds ? bprm->executable : bprm->file;  in bprm_creds_from_file()
1657 	bprm_fill_uid(bprm, file);  in bprm_creds_from_file()
1658 	return security_bprm_creds_from_file(bprm, file);  in bprm_creds_from_file()
1667 static int prepare_binprm(struct linux_binprm *bprm)  in prepare_binprm()  argument
1671 	memset(bprm->buf, 0, BINPRM_BUF_SIZE);  in prepare_binprm()
1672 	return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos);  in prepare_binprm()
1680 int remove_arg_zero(struct linux_binprm *bprm)  in remove_arg_zero()  argument
1687 	if (!bprm->argc)  in remove_arg_zero()
1691 		offset = bprm->p & ~PAGE_MASK;  in remove_arg_zero()
1692 		page = get_arg_page(bprm, bprm->p, 0);  in remove_arg_zero()
1700 				offset++, bprm->p++)  in remove_arg_zero()
1707 	bprm->p++;  in remove_arg_zero()
1708 	bprm->argc--;  in remove_arg_zero()
1720 static int search_binary_handler(struct linux_binprm *bprm)  in search_binary_handler()  argument
1726 	retval = prepare_binprm(bprm);  in search_binary_handler()
1730 	retval = security_bprm_check(bprm);  in search_binary_handler()
1742 		retval = fmt->load_binary(bprm);  in search_binary_handler()
1746 		if (bprm->point_of_no_return || (retval != -ENOEXEC)) {  in search_binary_handler()
1754 		if (printable(bprm->buf[0]) && printable(bprm->buf[1]) &&  in search_binary_handler()
1755 		    printable(bprm->buf[2]) && printable(bprm->buf[3]))  in search_binary_handler()
1757 		if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0)  in search_binary_handler()
1767 static int exec_binprm(struct linux_binprm *bprm)  in exec_binprm()  argument
1784 		ret = search_binary_handler(bprm);  in exec_binprm()
1787 		if (!bprm->interpreter)  in exec_binprm()
1790 		exec = bprm->file;  in exec_binprm()
1791 		bprm->file = bprm->interpreter;  in exec_binprm()
1792 		bprm->interpreter = NULL;  in exec_binprm()
1795 		if (unlikely(bprm->have_execfd)) {  in exec_binprm()
1796 			if (bprm->executable) {  in exec_binprm()
1800 			bprm->executable = exec;  in exec_binprm()
1805 	audit_bprm(bprm);  in exec_binprm()
1806 	trace_sched_process_exec(current, old_pid, bprm);  in exec_binprm()
1815 static int bprm_execve(struct linux_binprm *bprm,  in bprm_execve()  argument
1821 	retval = prepare_bprm_creds(bprm);  in bprm_execve()
1830 	check_unsafe_exec(bprm);  in bprm_execve()
1841 	bprm->file = file;  in bprm_execve()
1851 	if (bprm->fdpath && get_close_on_exec(fd))  in bprm_execve()
1852 		bprm->interp_flags |= BINPRM_FLAGS_PATH_INACCESSIBLE;  in bprm_execve()
1855 	retval = security_bprm_creds_for_exec(bprm);  in bprm_execve()
1859 	retval = exec_binprm(bprm);  in bprm_execve()
1880 	if (bprm->point_of_no_return && !fatal_signal_pending(current))  in bprm_execve()
1896 	struct linux_binprm *bprm;  in do_execveat_common()  local
1918 	bprm = alloc_bprm(fd, filename);  in do_execveat_common()
1919 	if (IS_ERR(bprm)) {  in do_execveat_common()
1920 		retval = PTR_ERR(bprm);  in do_execveat_common()
1927 			     current->comm, bprm->filename);  in do_execveat_common()
1930 	bprm->argc = retval;  in do_execveat_common()
1935 	bprm->envc = retval;  in do_execveat_common()
1937 	retval = bprm_stack_limits(bprm);  in do_execveat_common()
1941 	retval = copy_string_kernel(bprm->filename, bprm);  in do_execveat_common()
1944 	bprm->exec = bprm->p;  in do_execveat_common()
1946 	retval = copy_strings(bprm->envc, envp, bprm);  in do_execveat_common()
1950 	retval = copy_strings(bprm->argc, argv, bprm);  in do_execveat_common()
1960 	if (bprm->argc == 0) {  in do_execveat_common()
1961 		retval = copy_string_kernel("", bprm);  in do_execveat_common()
1964 		bprm->argc = 1;  in do_execveat_common()
1967 	retval = bprm_execve(bprm, fd, filename, flags);  in do_execveat_common()
1969 	free_bprm(bprm);  in do_execveat_common()
1980 	struct linux_binprm *bprm;  in kernel_execve()  local
1992 	bprm = alloc_bprm(fd, filename);  in kernel_execve()
1993 	if (IS_ERR(bprm)) {  in kernel_execve()
1994 		retval = PTR_ERR(bprm);  in kernel_execve()
2003 	bprm->argc = retval;  in kernel_execve()
2008 	bprm->envc = retval;  in kernel_execve()
2010 	retval = bprm_stack_limits(bprm);  in kernel_execve()
2014 	retval = copy_string_kernel(bprm->filename, bprm);  in kernel_execve()
2017 	bprm->exec = bprm->p;  in kernel_execve()
2019 	retval = copy_strings_kernel(bprm->envc, envp, bprm);  in kernel_execve()
2023 	retval = copy_strings_kernel(bprm->argc, argv, bprm);  in kernel_execve()
2027 	retval = bprm_execve(bprm, fd, filename, 0);  in kernel_execve()
2029 	free_bprm(bprm);  in kernel_execve()