[PATCH] scripts/selinux/mdp: fix initial SID handling

[PATCH] scripts/selinux/mdp: fix initial SID handling

[Stephen Smalley]

commit e3e0b582c321 ("selinux: remove unused initial SIDs and improve
handling") broke scripts/selinux/mdp since the unused initial SID names
were removed and the corresponding generation of policy initial SID
definitions by mdp was not updated accordingly.  Fix it.  With latest
upstream checkpolicy it is no longer necessary to include the SID context
definitions for the unused initial SIDs but retain them for compatibility
with older checkpolicy.

Fixes: e3e0b582c321 ("selinux: remove unused initial SIDs and improve handling")
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
---
 scripts/selinux/mdp/mdp.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c
index 576d11a60417..6ceb88eb9b59 100644
--- a/scripts/selinux/mdp/mdp.c
+++ b/scripts/selinux/mdp/mdp.c
@@ -67,8 +67,14 @@ int main(int argc, char *argv[])
 
 	initial_sid_to_string_len = sizeof(initial_sid_to_string) / sizeof (char *);
 	/* print out the sids */
-	for (i = 1; i < initial_sid_to_string_len; i++)
-		fprintf(fout, "sid %s\n", initial_sid_to_string[i]);
+	for (i = 1; i < initial_sid_to_string_len; i++) {
+		const char *name = initial_sid_to_string[i];
+
+		if (name)
+			fprintf(fout, "sid %s\n", name);
+		else
+			fprintf(fout, "sid unused%d\n", i);
+	}
 	fprintf(fout, "\n");
 
 	/* print out the class permissions */
@@ -126,9 +132,16 @@ int main(int argc, char *argv[])
 #define OBJUSERROLETYPE "user_u:object_r:base_t"
 
 	/* default sids */
-	for (i = 1; i < initial_sid_to_string_len; i++)
-		fprintf(fout, "sid %s " SUBJUSERROLETYPE "%s\n",
-			initial_sid_to_string[i], mls ? ":" SYSTEMLOW : "");
+	for (i = 1; i < initial_sid_to_string_len; i++) {
+		const char *name = initial_sid_to_string[i];
+
+		if (name)
+			fprintf(fout, "sid %s ", name);
+		else
+			fprintf(fout, "sid unused%d\n", i);
+		fprintf(fout, SUBJUSERROLETYPE "%s\n",
+			mls ? ":" SYSTEMLOW : "");
+	}
 	fprintf(fout, "\n");
 
 #define FS_USE(behavior, fstype)			    \
-- 
2.25.1

Re: [PATCH] scripts/selinux/mdp: fix initial SID handling

[Paul Moore]

On Wed, Jun 17, 2020 at 3:22 PM Stephen Smalley
<stephen.smalley.work@gmail.com> wrote:
>
> commit e3e0b582c321 ("selinux: remove unused initial SIDs and improve
> handling") broke scripts/selinux/mdp since the unused initial SID names
> were removed and the corresponding generation of policy initial SID
> definitions by mdp was not updated accordingly.  Fix it.  With latest
> upstream checkpolicy it is no longer necessary to include the SID context
> definitions for the unused initial SIDs but retain them for compatibility
> with older checkpolicy.
>
> Fixes: e3e0b582c321 ("selinux: remove unused initial SIDs and improve handling")
> Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
> ---
>  scripts/selinux/mdp/mdp.c | 23 ++++++++++++++++++-----
>  1 file changed, 18 insertions(+), 5 deletions(-)

Merged into selinux/next, thanks Stephen.

-- 
paul moore
www.paul-moore.com