From: Eric Biggers ebiggers@google.com
commit eb455dbd02cb1074b37872ffca30a81cb2a18eaa upstream.
Currently if the comparison fuzz tests encounter an encryption error when generating an skcipher or AEAD test vector, they will still test the decryption side (passing it the uninitialized ciphertext buffer) and expect it to fail with the same error.
This is sort of broken because it's not well-defined usage of the API to pass an uninitialized buffer, and furthermore in the AEAD case it's acceptable for the decryption error to be EBADMSG (meaning "inauthentic input") even if the encryption error was something else like EINVAL.
Fix this for skcipher by explicitly initializing the ciphertext buffer on error, and for AEAD by skipping the decryption test on error.
Reported-by: Pascal Van Leeuwen pvanleeuwen@verimatrix.com Fixes: d435e10e67be ("crypto: testmgr - fuzz skciphers against their generic implementation") Fixes: 40153b10d91c ("crypto: testmgr - fuzz AEADs against their generic implementation") Signed-off-by: Eric Biggers ebiggers@google.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- crypto/testmgr.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)
--- a/crypto/testmgr.c +++ b/crypto/testmgr.c @@ -2102,6 +2102,7 @@ static void generate_random_aead_testvec * If the key or authentication tag size couldn't be set, no need to * continue to encrypt. */ + vec->crypt_error = 0; if (vec->setkey_error || vec->setauthsize_error) goto done;
@@ -2245,10 +2246,12 @@ static int test_aead_vs_generic_impl(con req, tsgls); if (err) goto out; - err = test_aead_vec_cfg(driver, DECRYPT, &vec, vec_name, cfg, - req, tsgls); - if (err) - goto out; + if (vec.crypt_error == 0) { + err = test_aead_vec_cfg(driver, DECRYPT, &vec, vec_name, + cfg, req, tsgls); + if (err) + goto out; + } cond_resched(); } err = 0; @@ -2678,6 +2681,15 @@ static void generate_random_cipher_testv skcipher_request_set_callback(req, 0, crypto_req_done, &wait); skcipher_request_set_crypt(req, &src, &dst, vec->len, iv); vec->crypt_error = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); + if (vec->crypt_error != 0) { + /* + * The only acceptable error here is for an invalid length, so + * skcipher decryption should fail with the same error too. + * We'll test for this. But to keep the API usage well-defined, + * explicitly initialize the ciphertext buffer too. + */ + memset((u8 *)vec->ctext, 0, vec->len); + } done: snprintf(name, max_namelen, ""random: len=%u klen=%u"", vec->len, vec->klen);