crytpfs: fix clobbering of crypto info on keymaster failure
Changing the device lock (even from swipe to none) will cause the
master key to be re-encrypted.
If at that point keymaster fails (e.g. due to an incompatible keymaster update)
cryptfs will write back the now-incomplete crypto metadata.
Upon next reboot, userdata can't be decrypted.
Now we don't bother writing on keymaster failure.
Bug: 19301883
Change-Id: I2b9a1278f8b4d333ac8d567e17e2263005e99409
diff --git a/cryptfs.c b/cryptfs.c
index d5ceaef..46e6be7 100644
--- a/cryptfs.c
+++ b/cryptfs.c
@@ -3285,6 +3285,7 @@
int cryptfs_changepw(int crypt_type, const char *newpw)
{
struct crypt_mnt_ftr crypt_ftr;
+ int rc;
/* This is only allowed after we've successfully decrypted the master key */
if (!master_key_saved) {
@@ -3310,18 +3311,20 @@
newpw = adjusted_passwd;
}
- encrypt_master_key(crypt_type == CRYPT_TYPE_DEFAULT ? DEFAULT_PASSWORD
+ rc = encrypt_master_key(crypt_type == CRYPT_TYPE_DEFAULT ? DEFAULT_PASSWORD
: newpw,
crypt_ftr.salt,
saved_master_key,
crypt_ftr.master_key,
&crypt_ftr);
-
+ free(adjusted_passwd);
+ if (rc) {
+ SLOGE("Encrypt master key failed: %d", rc);
+ return -1;
+ }
/* save the key */
put_crypt_ftr_and_key(&crypt_ftr);
- free(adjusted_passwd);
-
#ifdef CONFIG_HW_DISK_ENCRYPTION
if (!strcmp((char *)crypt_ftr.crypto_type_name, "aes-xts")) {
if (crypt_type == CRYPT_TYPE_DEFAULT) {