ext4 crypto: add missing locking for keyring_key access
Cc: stable@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c
index c5882b3..9a16d1e 100644
--- a/fs/ext4/crypto_key.c
+++ b/fs/ext4/crypto_key.c
@@ -213,9 +213,11 @@
res = -ENOKEY;
goto out;
}
+ down_read(&keyring_key->sem);
ukp = user_key_payload(keyring_key);
if (ukp->datalen != sizeof(struct ext4_encryption_key)) {
res = -EINVAL;
+ up_read(&keyring_key->sem);
goto out;
}
master_key = (struct ext4_encryption_key *)ukp->data;
@@ -226,10 +228,12 @@
"ext4: key size incorrect: %d\n",
master_key->size);
res = -ENOKEY;
+ up_read(&keyring_key->sem);
goto out;
}
res = ext4_derive_key_aes(ctx.nonce, master_key->raw,
raw_key);
+ up_read(&keyring_key->sem);
if (res)
goto out;
got_key: