[PATCH-next 3/3] crypto: cipher - On clone do crypto_mod_get()

Dmitry Safonov
2023-06-14T17:47:21Z

The refcounter of underlying algorithm should be incremented, otherwise
it'll be destroyed with the cloned cipher, wrecking the original cipher.

Signed-off-by: Dmitry Safonov <dima@arista.com>
---
crypto/cipher.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/crypto/cipher.c b/crypto/cipher.c
index 184188339a4a..b53bf3cda826 100644
--- a/crypto/cipher.c
+++ b/crypto/cipher.c
@@ -101,10 +101,15 @@ struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher)
if (alg->cra_init)
return ERR_PTR(-ENOSYS);

+ if (unlikely(!crypto_mod_get(alg)))
+ return ERR_PTR(-ESTALE);
+
ntfm = __crypto_alloc_tfm(alg, CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK, GFP_ATOMIC);
- if (IS_ERR(ntfm))
+ if (IS_ERR(ntfm)) {
+ crypto_mod_put(alg);
return ERR_CAST(ntfm);
+ }

ntfm->crt_flags = tfm->crt_flags;

--
2.40.0