Commit e8c99200 authored Jul 24, 2019 by Jia-Ju Bai Committed by Ilya Dryomov Aug 28, 2019

libceph: don't call crypto_free_sync_skcipher() on a NULL tfm



In set_secret(), key->tfm is assigned to NULL on line 55, and then
ceph_crypto_key_destroy(key) is executed.

ceph_crypto_key_destroy(key)
  crypto_free_sync_skcipher(key->tfm)
    crypto_free_skcipher(&tfm->base);

This happens to work because crypto_sync_skcipher is a trivial wrapper
around crypto_skcipher: &tfm->base is still 0 and crypto_free_skcipher()
handles that.  Let's not rely on the layout of crypto_sync_skcipher.

This bug is found by a static analysis tool STCheck written by us.

Fixes: 69d6302b ("libceph: Remove VLA usage of skcipher").
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

parent a55aa89a

net/ceph/crypto.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -136,10 +136,12 @@ void ceph_crypto_key_destroy(struct ceph_crypto_key *key)
		if (key) {
		kfree(key->key);
		key->key = NULL;
		if (key->tfm) {
		crypto_free_sync_skcipher(key->tfm);
		key->tfm = NULL;
		}
		}
		}

		static const u8 aes_iv = (u8 )CEPH_AES_IV;