libsepol: fix build failure for refpolicy-mls

Backport a patch to fix build failure for refpolicy-mls:
| Creating mls xserver.pp policy package
| libsepol.validate_user_datum: Invalid user datum
| libsepol.validate_datum_array_entries: Invalid datum array entries
| libsepol.validate_policydb: Invalid policydb
| /buildarea/build/tmp/work/qemux86_64-poky-linux/refpolicy-mls/2.20220520+gitAUTOINC+f311d401cd-r0/recipe-sysroot-native/usr/bin/semodule_package:
Error while reading policy module from tmp/xserver.mod
| make: *** [Rules.modular:98: xserver.pp] Error 1

Signed-off-by: Yi Zhao <yi.zhao@windriver.com>
Signed-off-by: Joe MacDonald <joe@deserted.net>

2 files changed, 82 insertions, 0 deletions

diff --git a/recipes-security/selinux/libsepol/0001-libsepol-fix-validation-of-user-declarations-in-modu.patch b/recipes-security/selinux/libsepol/0001-libsepol-fix-validation-of-user-declarations-in-modu.patch
new file mode 100644
index 0000000..47c1806
--- /dev/null
+++ b/recipes-security/selinux/libsepol/0001-libsepol-fix-validation-of-user-declarations-in-modu.patch
@@ -0,0 +1,80 @@
+From 4831f73dd356fd72916f594dbeae44d26c93bb6b Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Christian=20G=C3=B6ttsche?= <cgzones@googlemail.com>
+Date: Tue, 7 Jun 2022 17:01:45 +0200
+Subject: [PATCH] libsepol: fix validation of user declarations in modules
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Users are allowed to be declared in modules. Modules do not get expanded
+leaving the `struct user_datum` members `exp_range` and `exp_dfltlevel`
+empty.
+Do no validate the expanded range and level for modular polices.
+
+Reported-by: bauen1 <j2468h@gmail.com>
+Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
+Acked-by: James Carter <jwcart2@gmail.com>
+
+Upstream-Status: Backport
+[https://github.com/SELinuxProject/selinux/commit/88a703399f3f44be2502fd4ecd22ac3d3c560694]
+
+Signed-off-by: Yi Zhao <yi.zhao@windriver.com>
+---
+ src/policydb_validate.c | 12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+diff --git a/src/policydb_validate.c b/src/policydb_validate.c
+index da18282..99d4eb7 100644
+--- a/src/policydb_validate.c
++++ b/src/policydb_validate.c
+@@ -18,7 +18,7 @@ typedef struct validate {
+ typedef struct map_arg {
+        validate_t *flavors;
+        sepol_handle_t *handle;
+-       int mls;
++       policydb_t *policy;
+ } map_arg_t;
+ 
+ static int create_gap_ebitmap(char **val_to_name, uint32_t nprim, ebitmap_t *gaps)
+@@ -571,7 +571,7 @@ static int validate_mls_range(mls_range_t *range, validate_t *sens, validate_t *
+        return -1;
+ }
+ 
+-static int validate_user_datum(sepol_handle_t *handle, user_datum_t *user, validate_t flavors[], int mls)
++static int validate_user_datum(sepol_handle_t *handle, user_datum_t *user, validate_t flavors[], policydb_t *p)
+ {
+        if (validate_value(user->s.value, &flavors[SYM_USERS]))
+                goto bad;
+@@ -581,9 +581,9 @@ static int validate_user_datum(sepol_handle_t *handle, user_datum_t *user, valid
+                goto bad;
+        if (validate_mls_semantic_level(&user->dfltlevel, &flavors[SYM_LEVELS], &flavors[SYM_CATS]))
+                goto bad;
+-       if (mls && validate_mls_range(&user->exp_range, &flavors[SYM_LEVELS], &flavors[SYM_CATS]))
++       if (p->mls && p->policy_type != POLICY_MOD && validate_mls_range(&user->exp_range, &flavors[SYM_LEVELS], &flavors[SYM_CATS]))
+                goto bad;
+-       if (mls && validate_mls_level(&user->exp_dfltlevel, &flavors[SYM_LEVELS], &flavors[SYM_CATS]))
++       if (p->mls && p->policy_type != POLICY_MOD && validate_mls_level(&user->exp_dfltlevel, &flavors[SYM_LEVELS], &flavors[SYM_CATS]))
+                goto bad;
+        if (user->bounds && validate_value(user->bounds, &flavors[SYM_USERS]))
+                goto bad;
+@@ -599,7 +599,7 @@ static int validate_user_datum_wrapper(__attribute__((unused)) hashtab_key_t k,
+ {
+        map_arg_t *margs = args;
+ 
+-       return validate_user_datum(margs->handle, d, margs->flavors, margs->mls);
++       return validate_user_datum(margs->handle, d, margs->flavors, margs->policy);
+ }
+ 
+ static int validate_bool_datum(sepol_handle_t *handle, cond_bool_datum_t *boolean, validate_t flavors[])
+@@ -689,7 +689,7 @@ static int validate_datum(__attribute__ ((unused))hashtab_key_t k, hashtab_datum
+ 
+ static int validate_datum_array_entries(sepol_handle_t *handle, policydb_t *p, validate_t flavors[])
+ {
+-       map_arg_t margs = { flavors, handle, p->mls };
++       map_arg_t margs = { flavors, handle, p };
+ 
+        if (hashtab_map(p->p_commons.table, validate_common_datum_wrapper, &margs))
+                goto bad;
+-- 
+2.25.1
+
diff --git a/recipes-security/selinux/libsepol_3.4.bb b/recipes-security/selinux/libsepol_3.4.bb
index 49312da..e756557 100644
--- a/recipes-security/selinux/libsepol_3.4.bb
+++ b/recipes-security/selinux/libsepol_3.4.bb
@@ -11,6 +11,8 @@ require selinux_common.inc
 
 inherit lib_package
 
+SRC_URI += "file://0001-libsepol-fix-validation-of-user-declarations-in-modu.patch"
+
 S = "${WORKDIR}/git/libsepol"
 
 DEPENDS = "flex-native"