Fix issue #6295373: "Package com.google.android.apps.authenticator2 has...
...mismatched uid: X on disk, Y in settings" errors on Froyo and Gingerbread
Deal more gracefully with the uid changing in three ways:
1. If the uid on disk has become root, then have installd change it to
the application's uid. This is to correct a potential case where
installd was interrupted while linking or unlinking the libs dir,
during which it temporarily changes the owner of the dir to root
so that a malicious app can not get in its way. So if the uid on
disk has become root, we assume we can safely just change it back
to the correct uid.
2. When scaning packages at boot, use the same "delete and rebuild data
directory" code for third party applications as we have for system
applications. This allows us to at least end up in a state where the
app will run, even if its data is lost.
3. But we really don't want to get in to case 2, so if an application
update is being installed and we find that the uid we now have for
the app is different than the one on disk, fail the update. This will
protect against for example a developer changing the sharedUserId of
their app and getting into this bad state.
Bug: 6295373
Change-Id: Ic802fdd818ac62449ff3c61d1fff1aa4d4942f39
diff --git a/cmds/installd/commands.c b/cmds/installd/commands.c
index 203d180..0bc7371 100644
--- a/cmds/installd/commands.c
+++ b/cmds/installd/commands.c
@@ -106,6 +106,43 @@
return 0;
}
+int fix_uid(const char *pkgname, uid_t uid, gid_t gid)
+{
+ char pkgdir[PKG_PATH_MAX];
+ struct stat s;
+ int rc = 0;
+
+ if ((uid < AID_SYSTEM) || (gid < AID_SYSTEM)) {
+ ALOGE("invalid uid/gid: %d %d\n", uid, gid);
+ return -1;
+ }
+
+ if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, 0)) {
+ ALOGE("cannot create package path\n");
+ return -1;
+ }
+
+ if (stat(pkgdir, &s) < 0) return -1;
+
+ if (s.st_uid != 0 || s.st_gid != 0) {
+ ALOGE("fixing uid of non-root pkg: %s %d %d\n", pkgdir, s.st_uid, s.st_gid);
+ return -1;
+ }
+
+ if (chmod(pkgdir, 0751) < 0) {
+ ALOGE("cannot chmod dir '%s': %s\n", pkgdir, strerror(errno));
+ unlink(pkgdir);
+ return -errno;
+ }
+ if (chown(pkgdir, uid, gid) < 0) {
+ ALOGE("cannot chown dir '%s': %s\n", pkgdir, strerror(errno));
+ unlink(pkgdir);
+ return -errno;
+ }
+
+ return 0;
+}
+
int delete_user_data(const char *pkgname, uid_t persona)
{
char pkgdir[PKG_PATH_MAX];
@@ -950,7 +987,7 @@
out:
if (chmod(dataDir, s.st_mode) < 0) {
ALOGE("failed to chmod '%s': %s\n", dataDir, strerror(errno));
- return -errno;
+ rc = -errno;
}
if (chown(dataDir, s.st_uid, s.st_gid) < 0) {
@@ -1027,7 +1064,7 @@
out:
if (chmod(dataDir, s.st_mode) < 0) {
ALOGE("failed to chmod '%s': %s\n", dataDir, strerror(errno));
- return -1;
+ rc = -1;
}
if (chown(dataDir, s.st_uid, s.st_gid) < 0) {
diff --git a/cmds/installd/installd.c b/cmds/installd/installd.c
index c2c749a..fa4b8a6 100644
--- a/cmds/installd/installd.c
+++ b/cmds/installd/installd.c
@@ -57,6 +57,11 @@
return renamepkg(arg[0], arg[1]); /* oldpkgname, newpkgname */
}
+static int do_fixuid(char **arg, char reply[REPLY_MAX])
+{
+ return fix_uid(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, gid */
+}
+
static int do_free_cache(char **arg, char reply[REPLY_MAX]) /* TODO int:free_size */
{
return free_cache((int64_t)atoll(arg[0])); /* free_size */
@@ -141,6 +146,7 @@
{ "rmdex", 1, do_rm_dex },
{ "remove", 2, do_remove },
{ "rename", 2, do_rename },
+ { "fixuid", 3, do_fixuid },
{ "freecache", 1, do_free_cache },
{ "rmcache", 1, do_rm_cache },
{ "protect", 2, do_protect },
diff --git a/cmds/installd/installd.h b/cmds/installd/installd.h
index 78342bb..1b843fd 100644
--- a/cmds/installd/installd.h
+++ b/cmds/installd/installd.h
@@ -143,6 +143,7 @@
int install(const char *pkgname, uid_t uid, gid_t gid);
int uninstall(const char *pkgname, uid_t persona);
int renamepkg(const char *oldpkgname, const char *newpkgname);
+int fix_uid(const char *pkgname, uid_t uid, gid_t gid);
int delete_user_data(const char *pkgname, uid_t persona);
int make_user_data(const char *pkgname, uid_t uid, uid_t persona);
int delete_persona(uid_t persona);
diff --git a/core/java/android/content/pm/PackageManager.java b/core/java/android/content/pm/PackageManager.java
index bcdd012..6de69b0 100644
--- a/core/java/android/content/pm/PackageManager.java
+++ b/core/java/android/content/pm/PackageManager.java
@@ -520,6 +520,14 @@
public static final int INSTALL_FAILED_PACKAGE_CHANGED = -23;
/**
+ * Installation return code: this is passed to the {@link IPackageInstallObserver} by
+ * {@link #installPackage(android.net.Uri, IPackageInstallObserver, int)} if
+ * the new package is assigned a different UID than it previously held.
+ * @hide
+ */
+ public static final int INSTALL_FAILED_UID_CHANGED = -24;
+
+ /**
* Installation parse return code: this is passed to the {@link IPackageInstallObserver} by
* {@link #installPackage(android.net.Uri, IPackageInstallObserver, int)}
* if the parser was given a path that is not a file, or does not end with the expected
diff --git a/services/java/com/android/server/pm/Installer.java b/services/java/com/android/server/pm/Installer.java
index 9b1973e..48004bb 100644
--- a/services/java/com/android/server/pm/Installer.java
+++ b/services/java/com/android/server/pm/Installer.java
@@ -243,6 +243,17 @@
return execute(builder.toString());
}
+ public int fixUid(String name, int uid, int gid) {
+ StringBuilder builder = new StringBuilder("fixuid");
+ builder.append(' ');
+ builder.append(name);
+ builder.append(' ');
+ builder.append(uid);
+ builder.append(' ');
+ builder.append(gid);
+ return execute(builder.toString());
+ }
+
public int deleteCacheFiles(String name) {
StringBuilder builder = new StringBuilder("rmcache");
builder.append(' ');
diff --git a/services/java/com/android/server/pm/PackageManagerService.java b/services/java/com/android/server/pm/PackageManagerService.java
index 88f5ec5..4882508 100644
--- a/services/java/com/android/server/pm/PackageManagerService.java
+++ b/services/java/com/android/server/pm/PackageManagerService.java
@@ -191,6 +191,7 @@
static final int SCAN_NO_PATHS = 1<<5;
static final int SCAN_UPDATE_TIME = 1<<6;
static final int SCAN_DEFER_DEX = 1<<7;
+ static final int SCAN_BOOTING = 1<<8;
static final int REMOVE_CHATTY = 1<<16;
@@ -924,7 +925,7 @@
// Set flag to monitor and not change apk file paths when
// scanning install directories.
- int scanMode = SCAN_MONITOR | SCAN_NO_PATHS | SCAN_DEFER_DEX;
+ int scanMode = SCAN_MONITOR | SCAN_NO_PATHS | SCAN_DEFER_DEX | SCAN_BOOTING;
if (mNoDexOpt) {
Slog.w(TAG, "Running ENG build: no pre-dexopt!");
scanMode |= SCAN_NO_DEX;
@@ -3750,17 +3751,34 @@
} else {
// This is a normal package, need to make its data directory.
dataPath = getDataPathForPackage(pkg.packageName, 0);
-
+
boolean uidError = false;
-
+
if (dataPath.exists()) {
+ // XXX should really do this check for each user.
mOutPermissions[1] = 0;
FileUtils.getPermissions(dataPath.getPath(), mOutPermissions);
// If we have mismatched owners for the data path, we have a problem.
if (mOutPermissions[1] != pkg.applicationInfo.uid) {
boolean recovered = false;
- if ((parseFlags&PackageParser.PARSE_IS_SYSTEM) != 0) {
+ if (mOutPermissions[1] == 0) {
+ // The directory somehow became owned by root. Wow.
+ // This is probably because the system was stopped while
+ // installd was in the middle of messing with its libs
+ // directory. Ask installd to fix that.
+ int ret = mInstaller.fixUid(pkgName, pkg.applicationInfo.uid,
+ pkg.applicationInfo.uid);
+ if (ret >= 0) {
+ recovered = true;
+ String msg = "Package " + pkg.packageName
+ + " unexpectedly changed to uid 0; recovered to " +
+ + pkg.applicationInfo.uid;
+ reportSettingsProblem(Log.WARN, msg);
+ }
+ }
+ if (!recovered && ((parseFlags&PackageParser.PARSE_IS_SYSTEM) != 0
+ || (scanMode&SCAN_BOOTING) != 0)) {
// If this is a system app, we can at least delete its
// current data so the application will still work.
int ret = mInstaller.remove(pkgName, 0);
@@ -3769,7 +3787,9 @@
// Remove the data directories for all users
sUserManager.removePackageForAllUsers(pkgName);
// Old data gone!
- String msg = "System package " + pkg.packageName
+ String prefix = (parseFlags&PackageParser.PARSE_IS_SYSTEM) != 0
+ ? "System package " : "Third party package ";
+ String msg = prefix + pkg.packageName
+ " has changed from uid: "
+ mOutPermissions[1] + " to "
+ pkg.applicationInfo.uid + "; old data erased";
@@ -3781,7 +3801,7 @@
pkg.applicationInfo.uid);
if (ret == -1) {
// Ack should not happen!
- msg = "System package " + pkg.packageName
+ msg = prefix + pkg.packageName
+ " could not have data directory re-created after delete.";
reportSettingsProblem(Log.WARN, msg);
mLastScanError = PackageManager.INSTALL_FAILED_INSUFFICIENT_STORAGE;
@@ -3794,6 +3814,11 @@
if (!recovered) {
mHasSystemUidErrors = true;
}
+ } else if (!recovered) {
+ // If we allow this install to proceed, we will be broken.
+ // Abort, abort!
+ mLastScanError = PackageManager.INSTALL_FAILED_UID_CHANGED;
+ return null;
}
if (!recovered) {
pkg.applicationInfo.dataDir = "/mismatched_uid/settings_"