On Mon, May 11, 2020 at 03:01:06PM -0400, James Carter wrote: > On Mon, May 11, 2020 at 2:09 PM Stephen Smalley > <stephen.smalley.work@xxxxxxxxx> wrote: > > > > On Mon, May 11, 2020 at 2:03 PM James Carter <jwcart2@xxxxxxxxx> wrote: > > > > > > On Mon, May 11, 2020 at 9:25 AM James Carter <jwcart2@xxxxxxxxx> wrote: > > > > > > > > On Mon, May 11, 2020 at 8:27 AM Petr Lautrbach <plautrba@xxxxxxxxxx> wrote: > > > > > > > > > > On Thu, Mar 05, 2020 at 02:53:37PM +0100, Ondrej Mosnacek wrote: > > > > > > The value attrs_expand_size == 1 removes all empty attributes, but it > > > > > > also makes sense to expand all attributes that have only one type. This > > > > > > removes some redundant rules (there is sometimes the same rule for the > > > > > > type and the attribute) and reduces the number of attributes that the > > > > > > kernel has to go through when looking up rules. > > > > > > > > > > > > Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx> > > > > > > --- > > > > > > > > > > > > v2: fix typos (Tne -> The; cointains -> contains) > > > > > > > > > > > > libsepol/cil/src/cil.c | 3 ++- > > > > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > > > > > > > diff --git a/libsepol/cil/src/cil.c b/libsepol/cil/src/cil.c > > > > > > index d222ad3a..c010ca2a 100644 > > > > > > --- a/libsepol/cil/src/cil.c > > > > > > +++ b/libsepol/cil/src/cil.c > > > > > > @@ -452,7 +452,8 @@ void cil_db_init(struct cil_db **db) > > > > > > (*db)->disable_dontaudit = CIL_FALSE; > > > > > > (*db)->disable_neverallow = CIL_FALSE; > > > > > > (*db)->attrs_expand_generated = CIL_FALSE; > > > > > > - (*db)->attrs_expand_size = 1; > > > > > > + /* 2 == remove attributes that contain none or just 1 type */ > > > > > > + (*db)->attrs_expand_size = 2; > > > > > > (*db)->preserve_tunables = CIL_FALSE; > > > > > > (*db)->handle_unknown = -1; > > > > > > (*db)->mls = -1; > > > > > > -- > > > > > > 2.24.1 > > > > > > > > > > > > > > > > > > > > > This patch broke `semanage node -l` on Fedora [1] > > > > > > > > > > :: [ 21:25:25 ] :: [ BEGIN ] :: Running 'make LIBDIR=/usr/lib64 SHLIBDIR=/lib64 test' > > > > > ... > > > > > test_list (__main__.SemanageTests) ... Traceback (most recent call last): > > > > > File "/usr/sbin/semanage", line 967, in <module> > > > > > do_parser() > > > > > File "/usr/sbin/semanage", line 946, in do_parser > > > > > args.func(args) > > > > > File "/usr/sbin/semanage", line 649, in handleNode > > > > > OBJECT = object_dict['node'](args) > > > > > File "/usr/lib/python3.8/site-packages/seobject.py", line 1849, in __init__ > > > > > self.valid_types = list(list(sepolicy.info(sepolicy.ATTRIBUTE, "node_type"))[0]["types"]) > > > > > IndexError: list index out of range > > > > > > > > > > While the `IndexError: list index out of range` error can be simply fixed, it > > > > > uncovered the problem that semanage uses attibutes to list certain records - > > > > > node_type, port_type, file_type, device_node, ... and these attributes can disappear when > > > > > there's only 1 type assigned. > > > > > > > > > > I guess it should be reverted as there's no other way how to find out that a > > > > > type node_t is node_type. > > > > > > > > > > [1] https://jenkins-continuous-infra.apps.ci.centos.org/job/fedora-rawhide-pr-pipeline/3462/artifact/package-tests/logs/FAIL-upstream-err.log > > > > > > > > > > > I see now. python/semanage/seobject.py and > > > python/semanage/semanage-bash-completion.sh both assume that node_type > > > is always defined as an attribute in a policy. There seems to be quite > > > a lot that is assumed about policy in the python directory. > > > > > > This is not a bug in CIL or libsepol. Ideally the tests should have > > > their own policy and the python code should gracefully handle the > > > situation when its assumptions are wrong. If we need to revert this > > > patch in the short-term than I am ok with that. > > > > We can mark these attributes explicitly in policy to prevent their > > expansion, right? So while we cannot make this change right now > > without breaking compatibility with selinux userspace tools (not just > > tests), we could start marking these attributes on which the tools > > depend in policy and then later we can re-apply this? > > Yes, we can add the rule "expandattribute node_type false;" in policy > for node_type and any other attributes that are required to exist. > It doesn't seem to be propagated to cil: # cat mypolicy.te policy_module(mypolicy,1.0) type myapp_t; type myapp_log_t; attribute myattribute; expandattribute myattribute false; typeattribute myapp_t myattribute; allow myattribute myapp_log_t:file read; # make -f /usr/share/selinux/devel/Makefile mypolicy.pp make: 'mypolicy.pp' is up to date. # /usr/libexec/selinux/hll/pp mypolicy.pp (type myapp_t) (roletype object_r myapp_t) (type myapp_log_t) (roletype object_r myapp_log_t) (typeattribute myattribute) (typeattributeset myattribute (myapp_t )) (roleattributeset cil_gen_require system_r) (allow myattribute myapp_log_t (file (read))) But it works with mypolicy.cil which contains: (expandtypeattribute myattribute false) I'm not really experienced in writing policy but I still find the behaviour confusing. It's not only about `semanage`, you can hit this using `sesearch` as well, e.g. before policy is rebuilt with new libsepol, `sesearch -A -t node_type` finds about 535 rules with node_type, then you rebuild policy and it's 0. But if assign node_type to another type, it's again more than 536. For this particular attribute we can/should use `expandtypeattribute` but should be this expression used every time you have an attribute assigned to only 1 type? If it stays as it is, it definitely needs to be part of release notes.
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