From a44542ca74b7da5b44ba30c205c3244805bb0600 Mon Sep 17 00:00:00 2001
From: Serban Constantinescu <serban.constantinescu@arm.com>
Date: Thu, 30 Jan 2014 15:16:45 +0000
Subject: [PATCH] ServiceManager: Add extra error handling

This patch extends the error handling. It also adds a check for a matching
binder version - kernel/userspace.

Change-Id: I43a262934b38c5711536aaa42754fed1ef04b39e
Signed-off-by: Serban Constantinescu <serban.constantinescu@arm.com>
---
 cmds/servicemanager/bctest.c          | 4 ++++
 cmds/servicemanager/binder.c          | 9 +++++++--
 cmds/servicemanager/service_manager.c | 4 ++++
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/cmds/servicemanager/bctest.c b/cmds/servicemanager/bctest.c
index ff5acedfa..ee49679fd 100644
--- a/cmds/servicemanager/bctest.c
+++ b/cmds/servicemanager/bctest.c
@@ -62,6 +62,10 @@ int main(int argc, char **argv)
     void *svcmgr = BINDER_SERVICE_MANAGER;
 
     bs = binder_open(128*1024);
+    if (!bs) {
+        fprintf(stderr, "failed to open binder driver\n");
+        return -1;
+    }
 
     argc--;
     argv++;
diff --git a/cmds/servicemanager/binder.c b/cmds/servicemanager/binder.c
index 43cb7d35c..7fdd841ed 100644
--- a/cmds/servicemanager/binder.c
+++ b/cmds/servicemanager/binder.c
@@ -94,6 +94,7 @@ struct binder_state
 struct binder_state *binder_open(unsigned mapsize)
 {
     struct binder_state *bs;
+    struct binder_version vers;
 
     bs = malloc(sizeof(*bs));
     if (!bs) {
@@ -108,6 +109,12 @@ struct binder_state *binder_open(unsigned mapsize)
         goto fail_open;
     }
 
+    if ((ioctl(bs->fd, BINDER_VERSION, &vers) == -1) ||
+        (vers.protocol_version != BINDER_CURRENT_PROTOCOL_VERSION)) {
+        fprintf(stderr, "binder: driver version differs from user space\n");
+        goto fail_open;
+    }
+
     bs->mapsize = mapsize;
     bs->mapped = mmap(NULL, mapsize, PROT_READ, MAP_PRIVATE, bs->fd, 0);
     if (bs->mapped == MAP_FAILED) {
@@ -116,8 +123,6 @@ struct binder_state *binder_open(unsigned mapsize)
         goto fail_map;
     }
 
-        /* TODO: check version */
-
     return bs;
 
 fail_map:
diff --git a/cmds/servicemanager/service_manager.c b/cmds/servicemanager/service_manager.c
index 3625e29f1..c8b219baf 100644
--- a/cmds/servicemanager/service_manager.c
+++ b/cmds/servicemanager/service_manager.c
@@ -275,6 +275,10 @@ int main(int argc, char **argv)
     void *svcmgr = BINDER_SERVICE_MANAGER;
 
     bs = binder_open(128*1024);
+    if (!bs) {
+        ALOGE("failed to open binder driver\n");
+        return -1;
+    }
 
     if (binder_become_context_manager(bs)) {
         ALOGE("cannot become context manager (%s)\n", strerror(errno));