Avoid error message when destroying key w/o secdiscardable file
Since commit 08f4bdfe9836 ("Don't use a secdiscardable file for keys
encrypted by SP") (https://r.android.com/2242561), some keys don't use a
secdiscardable file. Currently if such a key is destroyed, an ERROR
message like the following is logged:
E secdiscard: Secure discard open failed for: /data/misc/vold/user_keys/ce/14/current/secdiscardable
This case is expected, so it should not be an ERROR. Fix this by only
passing the secdiscardable file to the secdiscard program if it exists.
Bug: 232452368
Change-Id: I490289dfdaf0db6c3f4fb507509095e0033e2f69
diff --git a/KeyStorage.cpp b/KeyStorage.cpp
index 55c1709..837bb1a 100644
--- a/KeyStorage.cpp
+++ b/KeyStorage.cpp
@@ -660,8 +660,11 @@
kSecdiscardPath,
"--",
dir + "/" + kFn_encrypted_key,
- dir + "/" + kFn_secdiscardable,
};
+ auto secdiscardable = dir + "/" + kFn_secdiscardable;
+ if (pathExists(secdiscardable)) {
+ secdiscard_cmd.push_back(secdiscardable);
+ }
// Try each thing, even if previous things failed.
for (auto& fn : {kFn_keymaster_key_blob, kFn_keymaster_key_blob_upgraded}) {