ueventd: allow configuring SO_RCVBUF(FORCE) for the ueventd socket

Some configurations won't allow ueventd to have CAP_NET_ADMIN, so the
new default size of 16M is not possible for those.  Those
configurations also won't need such a large buffer size, so this
change allows devices to customize the SO_RCVBUF(FORCE) size for the
uevent socket.

This is done by adding the line 'uevent_socket_rcvbuf_size <size>' to
your device's ueventd.rc file.  <size> is specified as a byte count,
for example '16M' is 16MiB.

The last parsed uevent_socket_rcvbuf_size line is the one that is
used.

Bug: 120485624
Test: boot sailfish
Test: ueventd unit tests
Change-Id: If8123b92ca8a9b089ad50318caada2f21bc94707

1 files changed, 17 insertions, 2 deletions

diff --git a/init/ueventd_parser_test.cpp b/init/ueventd_parser_test.cpp
index c3af341c6..9c1cedf8b 100644
--- a/init/ueventd_parser_test.cpp
+++ b/init/ueventd_parser_test.cpp
@@ -138,6 +138,15 @@ firmware_directories /more
     TestUeventdFile(ueventd_file, {{}, {}, {}, firmware_directories});
 }
 
+TEST(ueventd_parser, UeventSocketRcvbufSize) {
+    auto ueventd_file = R"(
+uevent_socket_rcvbuf_size 8k
+uevent_socket_rcvbuf_size 8M
+)";
+
+    TestUeventdFile(ueventd_file, {{}, {}, {}, {}, false, 8 * 1024 * 1024});
+}
+
 TEST(ueventd_parser, AllTogether) {
     auto ueventd_file = R"(
 
@@ -169,6 +178,8 @@ subsystem test_devpath_dirname
 /sys/devices/virtual/*/input   poll_delay  0660  root   input
 firmware_directories /more
 
+uevent_socket_rcvbuf_size 6M
+
 #ending comment
 )";
 
@@ -197,8 +208,10 @@ firmware_directories /more
             "/more",
     };
 
-    TestUeventdFile(ueventd_file,
-                    {subsystems, sysfs_permissions, permissions, firmware_directories});
+    size_t uevent_socket_rcvbuf_size = 6 * 1024 * 1024;
+
+    TestUeventdFile(ueventd_file, {subsystems, sysfs_permissions, permissions, firmware_directories,
+                                   false, uevent_socket_rcvbuf_size});
 }
 
 // All of these lines are ill-formed, so test that there is 0 output.
@@ -213,6 +226,8 @@ firmware_directories #no directory listed
 /sys/devices/platform/trusty.*      trusty_version        0440  baduidbad   log
 /sys/devices/platform/trusty.*      trusty_version        0440  root   baduidbad
 
+uevent_socket_rcvbuf_size blah
+
 subsystem #no name
 
 )";