syscalls: implement execveat() system call (51f39a1f) · Commits · e / devices / android_kernel_oneplus_sm8150

fs/binfmt_em86.c

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -42,6 +42,10 @@ static int load_em86(struct linux_binprm *bprm)
	return -ENOEXEC;		return -ENOEXEC;
	}		}

			/* Need to be able to load the file after exec */
			if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
			return -ENOENT;

	allow_write_access(bprm->file);		allow_write_access(bprm->file);
	fput(bprm->file);		fput(bprm->file);
	bprm->file = NULL;		bprm->file = NULL;

fs/binfmt_misc.c

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -144,6 +144,10 @@ static int load_misc_binary(struct linux_binprm *bprm)
	if (!fmt)		if (!fmt)
	goto ret;		goto ret;

			/* Need to be able to load the file after exec */
			if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
			return -ENOENT;

	if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {		if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) {
	retval = remove_arg_zero(bprm);		retval = remove_arg_zero(bprm);
	if (retval)		if (retval)

fs/binfmt_script.c

+10 −0

Original line number	Original line	Diff line number	Diff line
	@@ -24,6 +24,16 @@ static int load_script(struct linux_binprm *bprm)

	if ((bprm->buf[0] != '#') \|\| (bprm->buf[1] != '!'))		if ((bprm->buf[0] != '#') \|\| (bprm->buf[1] != '!'))
	return -ENOEXEC;		return -ENOEXEC;

			/*
			* If the script filename will be inaccessible after exec, typically
			* because it is a "/dev/fd/<fd>/.." path against an O_CLOEXEC fd, give
			* up now (on the assumption that the interpreter will want to load
			* this file).
			*/
			if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
			return -ENOENT;

	/*		/*
	* This section does the #! interpretation.		* This section does the #! interpretation.
	* Sorta complicated, but hopefully it will work. -TYT		* Sorta complicated, but hopefully it will work. -TYT

fs/exec.c

+100 −13

Original line number	Original line	Diff line number	Diff line
	@@ -748,18 +748,25 @@ EXPORT_SYMBOL(setup_arg_pages);

	#endif /* CONFIG_MMU */		#endif /* CONFIG_MMU */

	static struct file do_open_exec(struct filename name)		static struct file do_open_execat(int fd, struct filename name, int flags)
	{		{
	struct file *file;		struct file *file;
	int err;		int err;
	static const struct open_flags open_exec_flags = {		struct open_flags open_exec_flags = {
	.open_flag = O_LARGEFILE \| O_RDONLY \| __FMODE_EXEC,		.open_flag = O_LARGEFILE \| O_RDONLY \| __FMODE_EXEC,
	.acc_mode = MAY_EXEC \| MAY_OPEN,		.acc_mode = MAY_EXEC \| MAY_OPEN,
	.intent = LOOKUP_OPEN,		.intent = LOOKUP_OPEN,
	.lookup_flags = LOOKUP_FOLLOW,		.lookup_flags = LOOKUP_FOLLOW,
	};		};

	file = do_filp_open(AT_FDCWD, name, &open_exec_flags);		if ((flags & ~(AT_SYMLINK_NOFOLLOW \| AT_EMPTY_PATH)) != 0)
			return ERR_PTR(-EINVAL);
			if (flags & AT_SYMLINK_NOFOLLOW)
			open_exec_flags.lookup_flags &= ~LOOKUP_FOLLOW;
			if (flags & AT_EMPTY_PATH)
			open_exec_flags.lookup_flags \|= LOOKUP_EMPTY;

			file = do_filp_open(fd, name, &open_exec_flags);
	if (IS_ERR(file))		if (IS_ERR(file))
	goto out;		goto out;

	@@ -770,12 +777,13 @@ static struct file do_open_exec(struct filename name)
	if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)		if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
	goto exit;		goto exit;

	fsnotify_open(file);

	err = deny_write_access(file);		err = deny_write_access(file);
	if (err)		if (err)
	goto exit;		goto exit;

			if (name->name[0] != '\0')
			fsnotify_open(file);

	out:		out:
	return file;		return file;

	@@ -787,7 +795,7 @@ static struct file do_open_exec(struct filename name)
	struct file open_exec(const char name)		struct file open_exec(const char name)
	{		{
	struct filename tmp = { .name = name };		struct filename tmp = { .name = name };
	return do_open_exec(&tmp);		return do_open_execat(AT_FDCWD, &tmp, 0);
	}		}
	EXPORT_SYMBOL(open_exec);		EXPORT_SYMBOL(open_exec);

	@@ -1428,10 +1436,12 @@ static int exec_binprm(struct linux_binprm *bprm)
	/*		/*
	* sys_execve() executes a new program.		* sys_execve() executes a new program.
	*/		*/
	static int do_execve_common(struct filename *filename,		static int do_execveat_common(int fd, struct filename *filename,
	struct user_arg_ptr argv,		struct user_arg_ptr argv,
	struct user_arg_ptr envp)		struct user_arg_ptr envp,
			int flags)
	{		{
			char *pathbuf = NULL;
	struct linux_binprm *bprm;		struct linux_binprm *bprm;
	struct file *file;		struct file *file;
	struct files_struct *displaced;		struct files_struct *displaced;
	@@ -1472,7 +1482,7 @@ static int do_execve_common(struct filename *filename,
	check_unsafe_exec(bprm);		check_unsafe_exec(bprm);
	current->in_execve = 1;		current->in_execve = 1;

	file = do_open_exec(filename);		file = do_open_execat(fd, filename, flags);
	retval = PTR_ERR(file);		retval = PTR_ERR(file);
	if (IS_ERR(file))		if (IS_ERR(file))
	goto out_unmark;		goto out_unmark;
	@@ -1480,7 +1490,28 @@ static int do_execve_common(struct filename *filename,
	sched_exec();		sched_exec();

	bprm->file = file;		bprm->file = file;
	bprm->filename = bprm->interp = filename->name;		if (fd == AT_FDCWD \|\| filename->name[0] == '/') {
			bprm->filename = filename->name;
			} else {
			if (filename->name[0] == '\0')
			pathbuf = kasprintf(GFP_TEMPORARY, "/dev/fd/%d", fd);
			else
			pathbuf = kasprintf(GFP_TEMPORARY, "/dev/fd/%d/%s",
			fd, filename->name);
			if (!pathbuf) {
			retval = -ENOMEM;
			goto out_unmark;
			}
			/*
			* Record that a name derived from an O_CLOEXEC fd will be
			* inaccessible after exec. Relies on having exclusive access to
			* current->files (due to unshare_files above).
			*/
			if (close_on_exec(fd, rcu_dereference_raw(current->files->fdt)))
			bprm->interp_flags \|= BINPRM_FLAGS_PATH_INACCESSIBLE;
			bprm->filename = pathbuf;
			}
			bprm->interp = bprm->filename;

	retval = bprm_mm_init(bprm);		retval = bprm_mm_init(bprm);
	if (retval)		if (retval)
	@@ -1521,6 +1552,7 @@ static int do_execve_common(struct filename *filename,
	acct_update_integrals(current);		acct_update_integrals(current);
	task_numa_free(current);		task_numa_free(current);
	free_bprm(bprm);		free_bprm(bprm);
			kfree(pathbuf);
	putname(filename);		putname(filename);
	if (displaced)		if (displaced)
	put_files_struct(displaced);		put_files_struct(displaced);
	@@ -1538,6 +1570,7 @@ static int do_execve_common(struct filename *filename,

	out_free:		out_free:
	free_bprm(bprm);		free_bprm(bprm);
			kfree(pathbuf);

	out_files:		out_files:
	if (displaced)		if (displaced)
	@@ -1553,7 +1586,18 @@ int do_execve(struct filename *filename,
	{		{
	struct user_arg_ptr argv = { .ptr.native = __argv };		struct user_arg_ptr argv = { .ptr.native = __argv };
	struct user_arg_ptr envp = { .ptr.native = __envp };		struct user_arg_ptr envp = { .ptr.native = __envp };
	return do_execve_common(filename, argv, envp);		return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
			}

			int do_execveat(int fd, struct filename *filename,
			const char __user const __user __argv,
			const char __user const __user __envp,
			int flags)
			{
			struct user_arg_ptr argv = { .ptr.native = __argv };
			struct user_arg_ptr envp = { .ptr.native = __envp };

			return do_execveat_common(fd, filename, argv, envp, flags);
	}		}

	#ifdef CONFIG_COMPAT		#ifdef CONFIG_COMPAT
	@@ -1569,7 +1613,23 @@ static int compat_do_execve(struct filename *filename,
	.is_compat = true,		.is_compat = true,
	.ptr.compat = __envp,		.ptr.compat = __envp,
	};		};
	return do_execve_common(filename, argv, envp);		return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
			}

			static int compat_do_execveat(int fd, struct filename *filename,
			const compat_uptr_t __user *__argv,
			const compat_uptr_t __user *__envp,
			int flags)
			{
			struct user_arg_ptr argv = {
			.is_compat = true,
			.ptr.compat = __argv,
			};
			struct user_arg_ptr envp = {
			.is_compat = true,
			.ptr.compat = __envp,
			};
			return do_execveat_common(fd, filename, argv, envp, flags);
	}		}
	#endif		#endif

	@@ -1609,6 +1669,20 @@ SYSCALL_DEFINE3(execve,
	{		{
	return do_execve(getname(filename), argv, envp);		return do_execve(getname(filename), argv, envp);
	}		}

			SYSCALL_DEFINE5(execveat,
			int, fd, const char __user *, filename,
			const char __user const __user , argv,
			const char __user const __user , envp,
			int, flags)
			{
			int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;

			return do_execveat(fd,
			getname_flags(filename, lookup_flags, NULL),
			argv, envp, flags);
			}

	#ifdef CONFIG_COMPAT		#ifdef CONFIG_COMPAT
	COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,		COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
	const compat_uptr_t __user *, argv,		const compat_uptr_t __user *, argv,
	@@ -1616,4 +1690,17 @@ COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
	{		{
	return compat_do_execve(getname(filename), argv, envp);		return compat_do_execve(getname(filename), argv, envp);
	}		}

			COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
			const char __user *, filename,
			const compat_uptr_t __user *, argv,
			const compat_uptr_t __user *, envp,
			int, flags)
			{
			int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;

			return compat_do_execveat(fd,
			getname_flags(filename, lookup_flags, NULL),
			argv, envp, flags);
			}
	#endif		#endif

fs/namei.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -130,7 +130,7 @@ void final_putname(struct filename *name)

	#define EMBEDDED_NAME_MAX (PATH_MAX - sizeof(struct filename))		#define EMBEDDED_NAME_MAX (PATH_MAX - sizeof(struct filename))

	static struct filename *		struct filename *
	getname_flags(const char __user filename, int flags, int empty)		getname_flags(const char __user filename, int flags, int empty)
	{		{
	struct filename result, err;		struct filename result, err;