From cee7fcd0016ef0e983d14256b4c9c63c37dc2ee4 Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <pcc@google.com>
Date: Thu, 14 Dec 2023 14:03:07 -0800
Subject: [PATCH] Mount /tmp as tmpfs.

/tmp is a volatile temporary storage location for the shell user.
As with /data/local/tmp, it is owned by shell:shell and is chmod 771.

Bug: 311263616
Change-Id: Ice0229d937989b097971d9db434d5589ac2da99a
---
 rootdir/Android.mk | 2 +-
 rootdir/init.rc    | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 7deb17324..7444f963f 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -97,7 +97,7 @@ endif
 # create some directories (some are mount points) and symlinks
 LOCAL_POST_INSTALL_CMD := mkdir -p $(addprefix $(TARGET_ROOT_OUT)/, \
     dev proc sys system data data_mirror odm oem acct config storage mnt apex bootstrap-apex debug_ramdisk \
-    linkerconfig second_stage_resources postinstall $(BOARD_ROOT_EXTRA_FOLDERS)); \
+    linkerconfig second_stage_resources postinstall tmp $(BOARD_ROOT_EXTRA_FOLDERS)); \
     ln -sf /system/bin $(TARGET_ROOT_OUT)/bin; \
     ln -sf /system/etc $(TARGET_ROOT_OUT)/etc; \
     ln -sf /data/user_de/0/com.android.shell/files/bugreports $(TARGET_ROOT_OUT)/bugreports; \
diff --git a/rootdir/init.rc b/rootdir/init.rc
index fb6473666..12c46ebfe 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -92,6 +92,12 @@ on early-init
     # checker programs.
     mkdir /dev/fscklogs 0770 root system
 
+    # Create tmpfs for use by the shell user.
+    mount tmpfs tmpfs /tmp
+    restorecon /tmp
+    chown shell shell /tmp
+    chmod 0771 /tmp
+
 on init
     sysclktz 0