Re: [PATCH -next 3/5] landlock/selftests: add selftests for chmod and chown

[xiujianfeng]

Hi，

在 2022/8/23 3:26, Günther Noack 写道:
> On Mon, Aug 22, 2022 at 07:46:59PM +0800, Xiu Jianfeng wrote:
> > +TEST_F_FORK(layout1, unhandled_chmod)
> > +{
> > +	const struct rule rules[] = {
> > +		{
> > +			.path = file2_s3d1,
> > +			.access = LANDLOCK_ACCESS_FS_READ_FILE |
> > +				  LANDLOCK_ACCESS_FS_WRITE_FILE,
> > +		},
> > +		{
> > +			.path = file3_s3d1,
> > +			.access = LANDLOCK_ACCESS_FS_READ_FILE |
> > +				  LANDLOCK_ACCESS_FS_WRITE_FILE,
> > +		},
> > +		{},
> > +	};
> > +	const int ruleset_fd =
> > +		create_ruleset(_metadata, ACCESS_RW, rules);
> > +
> > +	ASSERT_LE(0, ruleset_fd);
> > +	enforce_ruleset(_metadata, ruleset_fd);
> > +	ASSERT_EQ(0, close(ruleset_fd));
> > +
> > +	ASSERT_EQ(0, test_chmod(file2_s3d1));
> > +	ASSERT_EQ(0, test_fchmod(file2_s3d1));
> > +	ASSERT_EQ(0, test_chmod(file3_s3d1));
> > +	ASSERT_EQ(0, test_chmod(dir_s3d1));
> > +}
>
> I missed it in the previous mail:
>
> There are also the chown variants lchown() and fchownat(), as well as
> the chmod variant fchmodat(), which might be interesting to test,
> especially the symlink scenarios.
>
> fchmodat() has a AT_SYMLINK_NOFOLLOW flag which does the chmod
> equivalent to lchown().

man fchmodat shows as follows:
...
AT_SYMLINK_NOFOLLOW
If pathname is a symbolic link, do not dereference it: instead operate 
on the link itself. This flag is not currently implemented.
...

so I suppose this can not be test. Please correct me if I am wrong.
thanks.

> --
> .