Merge "Add derive_gid flag for mounting sdcardfs"
am: e3526a5ef9
Change-Id: I3543e1eb46866ed9b11a6d2d133de8edbf76cb2c
diff --git a/sdcard/sdcard.cpp b/sdcard/sdcard.cpp
index 343a903..77d5a91 100644
--- a/sdcard/sdcard.cpp
+++ b/sdcard/sdcard.cpp
@@ -319,17 +319,31 @@
LOG(FATAL) << "terminated prematurely";
}
-static bool sdcardfs_setup(const std::string& source_path, const std::string& dest_path, uid_t fsuid,
- gid_t fsgid, bool multi_user, userid_t userid, gid_t gid, mode_t mask) {
- std::string opts = android::base::StringPrintf("fsuid=%d,fsgid=%d,%smask=%d,userid=%d,gid=%d",
- fsuid, fsgid, multi_user?"multiuser,":"", mask, userid, gid);
+static bool sdcardfs_setup(const std::string& source_path, const std::string& dest_path,
+ uid_t fsuid, gid_t fsgid, bool multi_user, userid_t userid, gid_t gid,
+ mode_t mask, bool derive_gid) {
+ std::string opts = android::base::StringPrintf(
+ "fsuid=%d,fsgid=%d,%s%smask=%d,userid=%d,gid=%d", fsuid, fsgid,
+ multi_user ? "multiuser," : "", derive_gid ? "derive_gid," : "", mask, userid, gid);
if (mount(source_path.c_str(), dest_path.c_str(), "sdcardfs",
MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()) == -1) {
- PLOG(ERROR) << "failed to mount sdcardfs filesystem";
- return false;
+ if (derive_gid) {
+ PLOG(ERROR) << "trying to mount sdcardfs filesystem without derive_gid";
+ /* Maybe this isn't supported on this kernel. Try without. */
+ opts = android::base::StringPrintf("fsuid=%d,fsgid=%d,%smask=%d,userid=%d,gid=%d",
+ fsuid, fsgid, multi_user ? "multiuser," : "", mask,
+ userid, gid);
+ if (mount(source_path.c_str(), dest_path.c_str(), "sdcardfs",
+ MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()) == -1) {
+ PLOG(ERROR) << "failed to mount sdcardfs filesystem";
+ return false;
+ }
+ } else {
+ PLOG(ERROR) << "failed to mount sdcardfs filesystem";
+ return false;
+ }
}
-
return true;
}
@@ -355,7 +369,8 @@
}
static void run_sdcardfs(const std::string& source_path, const std::string& label, uid_t uid,
- gid_t gid, userid_t userid, bool multi_user, bool full_write) {
+ gid_t gid, userid_t userid, bool multi_user, bool full_write,
+ bool derive_gid) {
std::string dest_path_default = "/mnt/runtime/default/" + label;
std::string dest_path_read = "/mnt/runtime/read/" + label;
std::string dest_path_write = "/mnt/runtime/write/" + label;
@@ -365,10 +380,10 @@
// Multi-user storage is fully isolated per user, so "other"
// permissions are completely masked off.
if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
- AID_SDCARD_RW, 0006)
- || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY, 0027)
- || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write,
- AID_EVERYBODY, full_write ? 0007 : 0027)) {
+ AID_SDCARD_RW, 0006, derive_gid) ||
+ !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY, 0027) ||
+ !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write, AID_EVERYBODY,
+ full_write ? 0007 : 0027)) {
LOG(FATAL) << "failed to sdcardfs_setup";
}
} else {
@@ -376,11 +391,11 @@
// the Android directories are masked off to a single user
// deep inside attr_from_stat().
if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
- AID_SDCARD_RW, 0006)
- || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read,
- AID_EVERYBODY, full_write ? 0027 : 0022)
- || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write,
- AID_EVERYBODY, full_write ? 0007 : 0022)) {
+ AID_SDCARD_RW, 0006, derive_gid) ||
+ !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY,
+ full_write ? 0027 : 0022) ||
+ !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write, AID_EVERYBODY,
+ full_write ? 0007 : 0022)) {
LOG(FATAL) << "failed to sdcardfs_setup";
}
}
@@ -437,7 +452,8 @@
<< " -g: specify GID to run as"
<< " -U: specify user ID that owns device"
<< " -m: source_path is multi-user"
- << " -w: runtime write mount has full write access";
+ << " -w: runtime write mount has full write access"
+ << " -P preserve owners on the lower file system";
return 1;
}
@@ -449,12 +465,13 @@
userid_t userid = 0;
bool multi_user = false;
bool full_write = false;
+ bool derive_gid = false;
int i;
struct rlimit rlim;
int fs_version;
int opt;
- while ((opt = getopt(argc, argv, "u:g:U:mw")) != -1) {
+ while ((opt = getopt(argc, argv, "u:g:U:mwG")) != -1) {
switch (opt) {
case 'u':
uid = strtoul(optarg, NULL, 10);
@@ -471,6 +488,9 @@
case 'w':
full_write = true;
break;
+ case 'G':
+ derive_gid = true;
+ break;
case '?':
default:
return usage();
@@ -514,7 +534,7 @@
}
if (should_use_sdcardfs()) {
- run_sdcardfs(source_path, label, uid, gid, userid, multi_user, full_write);
+ run_sdcardfs(source_path, label, uid, gid, userid, multi_user, full_write, derive_gid);
} else {
run(source_path, label, uid, gid, userid, multi_user, full_write);
}