[PATCH v2 7/7] fs: HKDF - remove duplicate memory clearing

Stephan Müller
2021-01-24T14:09:38Z

The clearing of the OKM memory buffer in case of an error is already
performed by the HKDF implementation crypto_hkdf_expand. Thus, the
code clearing is not needed any more in the file system code base.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
fs/crypto/hkdf.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/fs/crypto/hkdf.c b/fs/crypto/hkdf.c
index ae236b42b1f0..c48dd8ca3a46 100644
--- a/fs/crypto/hkdf.c
+++ b/fs/crypto/hkdf.c
@@ -102,13 +102,10 @@ int fscrypt_hkdf_expand(const struct fscrypt_hkdf *hkdf, u8 context,
.iov_base = (u8 *)info,
.iov_len = infolen,
} };
- int err = crypto_hkdf_expand(hkdf->hmac_tfm,
- info_iov, ARRAY_SIZE(info_iov),
- okm, okmlen);

- if (unlikely(err))
- memzero_explicit(okm, okmlen); /* so caller doesn't need to */
- return err;
+ return crypto_hkdf_expand(hkdf->hmac_tfm,
+ info_iov, ARRAY_SIZE(info_iov),
+ okm, okmlen);
}

void fscrypt_destroy_hkdf(struct fscrypt_hkdf *hkdf)
--
2.26.2