openkylin
/
platform_system_core
mirror of https://gitee.com/openkylin/platform_system_core.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Protect runtime storage mount points. 

We have a bunch of magic that mounts the correct view of storage
access based on the runtime permissions of an app, but we forgot to
protect the real underlying data sources; oops.

This series of changes just bumps the directory heirarchy one level
to give us /mnt/runtime which we can mask off as 0700 to prevent
people from jumping to the exposed internals.

Also add CTS tests to verify that we're protecting access to
internal mount points like this.

Bug: 22964288
Change-Id: I32068e63a3362b37e8ebca1418f900bb8537b498
This commit is contained in:
Jeff Sharkey 2015-08-06 11:39:44 -07:00
parent d57125af1a
commit b9f438ff84
2 changed files with 13 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
rootdir/init.rc
View File

@ -69,16 +69,17 @@ on init
# Storage views to support runtime permissions
mkdir /storage 0755 root root
mkdir /mnt/runtime_default 0755 root root
mkdir /mnt/runtime_default/self 0755 root root
mkdir /mnt/runtime_read 0755 root root
mkdir /mnt/runtime_read/self 0755 root root
mkdir /mnt/runtime_write 0755 root root
mkdir /mnt/runtime_write/self 0755 root root
mkdir /mnt/runtime 0700 root root
mkdir /mnt/runtime/default 0755 root root
mkdir /mnt/runtime/default/self 0755 root root
mkdir /mnt/runtime/read 0755 root root
mkdir /mnt/runtime/read/self 0755 root root
mkdir /mnt/runtime/write 0755 root root
mkdir /mnt/runtime/write/self 0755 root root
# Symlink to keep legacy apps working in multi-user world
symlink /storage/self/primary /sdcard
symlink /mnt/user/0/primary /mnt/runtime_default/self/primary
symlink /mnt/user/0/primary /mnt/runtime/default/self/primary
# memory control cgroup
mkdir /dev/memcg 0700 root system
@ -216,7 +217,7 @@ on post-fs
# Mount shared so changes propagate into child namespaces
mount rootfs rootfs / shared rec
# Mount default storage into root namespace
mount none /mnt/runtime_default /storage slave bind rec
mount none /mnt/runtime/default /storage slave bind rec
# We chown/chmod /cache again so because mount is run as root + defaults
chown system cache /cache

8
sdcard/sdcard.c
View File

@ -1735,7 +1735,7 @@ static int usage() {
" -g: specify GID to run as\n"
" -U: specify user ID that owns device\n"
" -m: source_path is multi-user\n"
" -w: runtime_write mount has full write access\n"
" -w: runtime write mount has full write access\n"
"\n");
return 1;
}
@ -1822,9 +1822,9 @@ static void run(const char* source_path, const char* label, uid_t uid,
global.fuse_read = &fuse_read;
global.fuse_write = &fuse_write;
snprintf(fuse_default.dest_path, PATH_MAX, "/mnt/runtime_default/%s", label);
snprintf(fuse_read.dest_path, PATH_MAX, "/mnt/runtime_read/%s", label);
snprintf(fuse_write.dest_path, PATH_MAX, "/mnt/runtime_write/%s", label);
snprintf(fuse_default.dest_path, PATH_MAX, "/mnt/runtime/default/%s", label);
snprintf(fuse_read.dest_path, PATH_MAX, "/mnt/runtime/read/%s", label);
snprintf(fuse_write.dest_path, PATH_MAX, "/mnt/runtime/write/%s", label);
handler_default.fuse = &fuse_default;
handler_read.fuse = &fuse_read;