commit 6058926ec3546731c52ce072f21bf17e8f77ee31
author Suren Baghdasaryan <surenb@google.com> Mon Oct 21 17:59:22 2019 -0700
committer Suren Baghdasaryan <surenb@google.com> Thu Nov 07 18:18:46 2019 +0000
tree 754323ba1771e9ec286c86e41da8e4923e865dba
parent c06009246aa9ed3305154a072991e8828103b2df

lmkd: Prepare lmkd to support connection from init process

In order to register native services init needs ability to communicate with
lmkd. Make liblmkd_utils library available in recovery mode so that init
can link to it and add a data socket in lmkd to support additional
connection from init. Ensure SOCK_CLOEXEC type for lmkd socket to prevent
init children from inheriting it.

Bug: 129011369
Test: boot and verify native service registration
Change-Id: Iaa4f59282fb10f838f6811571e97d55754b1bd41
Signed-off-by: Suren Baghdasaryan <surenb@google.com>

lmkd/Android.bp

diff --git a/lmkd/Android.bp b/lmkd/Android.bp
index e8e125b..deebb8e 100644
--- a/lmkd/Android.bp
+++ b/lmkd/Android.bp
@@ -48,6 +48,7 @@
 cc_library_static {
     name: "liblmkd_utils",
     srcs: ["liblmkd_utils.c"],
+    recovery_available: true,
     shared_libs: [
         "libcutils",
     ],

lmkd/liblmkd_utils.c

diff --git a/lmkd/liblmkd_utils.c b/lmkd/liblmkd_utils.c
index fa3b7a9..980cd35 100644
--- a/lmkd/liblmkd_utils.c
+++ b/lmkd/liblmkd_utils.c
@@ -28,7 +28,7 @@
 int lmkd_connect() {
     return socket_local_client("lmkd",
                                ANDROID_SOCKET_NAMESPACE_RESERVED,
-                               SOCK_SEQPACKET);
+                               SOCK_SEQPACKET | SOCK_CLOEXEC);
 }
 
 int lmkd_register_proc(int sock, struct lmk_procprio *params) {

lmkd/lmkd.c

diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index e7a23ef..1edd772 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -245,8 +245,8 @@
     struct event_handler_info handler_info;
 };
 
-/* max supported number of data connections */
-#define MAX_DATA_CONN 2
+/* max supported number of data connections (AMS, init, tests) */
+#define MAX_DATA_CONN 3
 
 /* socket event handler data */
 static struct sock_event_handler_info ctrl_sock;
@@ -256,7 +256,7 @@
 static struct event_handler_info vmpressure_hinfo[VMPRESS_LEVEL_COUNT];
 
 /*
- * 1 ctrl listen socket, 2 ctrl data socket, 3 memory pressure levels,
+ * 1 ctrl listen socket, 3 ctrl data socket, 3 memory pressure levels,
  * 1 lmk events + 1 fd to wait for process death
  */
 #define MAX_EPOLL_EVENTS (1 + MAX_DATA_CONN + VMPRESS_LEVEL_COUNT + 1 + 1)