system_server: allow signull signal on zygote
This can be used as an existence check on a process
before calling kill (which is already granted).
Addresses:
avc: denied { signull } for comm="Binder:1328_1"
scontext=u:r:system_server:s0 tcontext=u:r:webview_zygote:s0
tclass=process permissive=0
Bug: 143627693
Test: build
Change-Id: I01dfe3c0cb2f4fec2d1f1191ee8243870cdd1bc6
diff --git a/private/system_server.te b/private/system_server.te
index fa59ef8..85b8191 100644
--- a/private/system_server.te
+++ b/private/system_server.te
@@ -37,10 +37,12 @@
allow system_server zygote:process sigchld;
# May kill zygote on crashes.
-allow system_server zygote:process sigkill;
-allow system_server crash_dump:process sigkill;
-allow system_server webview_zygote:process sigkill;
-allow system_server app_zygote:process sigkill;
+allow system_server {
+ app_zygote
+ crash_dump
+ webview_zygote
+ zygote
+}:process { sigkill signull };
# Read /system/bin/app_process.
allow system_server zygote_exec:file r_file_perms;