commit 4772f1da47bfdad8e0b3e3cdbf1bdc6bda0443b1
author Tom Cherry <tomcherry@google.com> Tue Jul 30 09:34:41 2019 -0700
committer Tom Cherry <tomcherry@google.com> Thu Aug 01 10:54:47 2019 -0700
tree 3f40d0bee7fa7394dc09ed9d73f2cd1d9f3d6932
parent c5cf85db23ac8c8a0206e911d73ef1c42ad66ed6

init: check the arguments of builtins during the build

Host init verifier already checks that the names and number of
arguments for builtins are correct, but it can check more.  This
change ensures that property expansions are well formed, and that
arguments that can be parsed on the host are correct.  For example it
checks that UIDs and GIDs exist, that numerical values can be parsed,
and that rlimit strings are correct.

Test: build

Change-Id: Ied8882498a88a9f8324db6b8d1020aeeccc8177b

init/service.cpp

diff --git a/init/service.cpp b/init/service.cpp
index 380c93b..e60c20d 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -635,7 +635,8 @@
     }
 }
 
-std::unique_ptr<Service> Service::MakeTemporaryOneshotService(const std::vector<std::string>& args) {
+Result<std::unique_ptr<Service>> Service::MakeTemporaryOneshotService(
+        const std::vector<std::string>& args) {
     // Parse the arguments: exec [SECLABEL [UID [GID]*] --] COMMAND ARGS...
     // SECLABEL can be a - to denote default
     std::size_t command_arg = 1;
@@ -646,13 +647,11 @@
         }
     }
     if (command_arg > 4 + NR_SVC_SUPP_GIDS) {
-        LOG(ERROR) << "exec called with too many supplementary group ids";
-        return nullptr;
+        return Error() << "exec called with too many supplementary group ids";
     }
 
     if (command_arg >= args.size()) {
-        LOG(ERROR) << "exec called without command";
-        return nullptr;
+        return Error() << "exec called without command";
     }
     std::vector<std::string> str_args(args.begin() + command_arg, args.end());
 
@@ -671,8 +670,7 @@
     if (command_arg > 3) {
         uid = DecodeUid(args[2]);
         if (!uid) {
-            LOG(ERROR) << "Unable to decode UID for '" << args[2] << "': " << uid.error();
-            return nullptr;
+            return Error() << "Unable to decode UID for '" << args[2] << "': " << uid.error();
         }
     }
     Result<gid_t> gid = 0;
@@ -680,16 +678,14 @@
     if (command_arg > 4) {
         gid = DecodeUid(args[3]);
         if (!gid) {
-            LOG(ERROR) << "Unable to decode GID for '" << args[3] << "': " << gid.error();
-            return nullptr;
+            return Error() << "Unable to decode GID for '" << args[3] << "': " << gid.error();
         }
         std::size_t nr_supp_gids = command_arg - 1 /* -- */ - 4 /* exec SECLABEL UID GID */;
         for (size_t i = 0; i < nr_supp_gids; ++i) {
             auto supp_gid = DecodeUid(args[4 + i]);
             if (!supp_gid) {
-                LOG(ERROR) << "Unable to decode GID for '" << args[4 + i]
-                           << "': " << supp_gid.error();
-                return nullptr;
+                return Error() << "Unable to decode GID for '" << args[4 + i]
+                               << "': " << supp_gid.error();
             }
             supp_gids.push_back(*supp_gid);
         }