Check setegid() return values
The clang static analyzer is complaining that we are not checking the
setegid() return value, so let's add these checks. We should never
fail to return to AID_ROOT, so fail hard in this case.
Bug: 26962034
Test: Boot bullhead
Test: export WITH_STATIC_ANALYZER=1 and run 'mm' in the project directory
Change-Id: I62e95b045c5734305c71502871b6cf17f152edbc
diff --git a/init/devices.cpp b/init/devices.cpp
index 5f54ff8..bd11f5f 100644
--- a/init/devices.cpp
+++ b/init/devices.cpp
@@ -251,7 +251,10 @@
* some device nodes, so the uid has to be set with chown() and is still
* racy. Fixing the gid race at least fixed the issue with system_server
* opening dynamic input devices under the AID_INPUT gid. */
- setegid(gid);
+ if (setegid(gid)) {
+ PLOG(ERROR) << "setegid(" << gid << ") for " << path << " device failed";
+ goto out;
+ }
/* If the node already exists update its SELinux label to handle cases when
* it was created with the wrong context during coldboot procedure. */
if (mknod(path, mode, dev) && (errno == EEXIST) && secontext) {
@@ -273,7 +276,9 @@
out:
chown(path, uid, -1);
- setegid(AID_ROOT);
+ if (setegid(AID_ROOT)) {
+ PLOG(FATAL) << "setegid(AID_ROOT) failed";
+ }
if (secontext) {
freecon(secontext);