On Mon, Feb 25, 2019 at 02:47:44PM -0800, Darrick J. Wong wrote:
> On Mon, Feb 25, 2019 at 02:10:52PM -0500, jeffm@xxxxxxxx wrote:
> > From: Jeff Mahoney <jeffm@xxxxxxxx>
> >
> > src/t_attr_corruption uses the security.evm extended attribute because
> > it sorts before security.posix_acl_access. The security.evm attribute
> > is a formatted structure and when passed an uninitialized buffer, it
> > will fail with EPERM.
> >
> > We see test failures like:
> > --- tests/generic/529.out2019-02-21 13:22:47.583406922 -0500
> > +++ /opt/xfstests/results//generic/529.out.bad 2019-02-21 13:57:31.967406922 -0500
> > @@ -1,2 +1,2 @@
> > QA output created by 529
> > -list attr: Numerical result out of range
> > +set evm: Operation not permitted
> >
> > This patch uses security.capability which also sorts where it needs to
> > do for the test and also accepts an unformatted buffer.
> >
> > Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx>
> > ---
> > src/t_attr_corruption.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/src/t_attr_corruption.c b/src/t_attr_corruption.c
> > index f26611f9..0c229dbc 100644
> > --- a/src/t_attr_corruption.c
> > +++ b/src/t_attr_corruption.c
> > @@ -76,7 +76,7 @@ int main(int argc, char *argv[])
> > if (ret)
> > die("set posix acl");
> >
> > - ret = fsetxattr(fd, "security.evm", buf, 1, 1);
> > + ret = fsetxattr(fd, "security.capability", buf, 1, 1);
>
> This fails for me both with and without EVM configured into my kernel:
>
> fsetxattr(3, "security.capability", "\3", 1, XATTR_CREATE) = -1 EINVAL (Invalid argument)
>
> Judging from fs/xattr.c it looks as though security.capability also has
> a defined format that's parsed by security/commoncap.c...
And now that I've figured out how to reproduce the xfs bug without a
second attribute, NAK to this and I'll send a more complete fix shortly.
--D
> --D
>
> > if (ret)
> > die("set evm");
> >
> > --
> > 2.16.4
> >
