From 453431a54934d917153c65211b2dabf45562ca88 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Thu, 6 Aug 2020 23:18:13 -0700 Subject: mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches Signed-off-by: Waiman Long Signed-off-by: Andrew Morton Acked-by: David Howells Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: Jarkko Sakkinen Cc: James Morris Cc: "Serge E. Hallyn" Cc: Joe Perches Cc: Matthew Wilcox Cc: David Rientjes Cc: Dan Carpenter Cc: "Jason A . Donenfeld" Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds --- net/sunrpc/auth_gss/gss_krb5_crypto.c | 4 ++-- net/sunrpc/auth_gss/gss_krb5_keys.c | 6 +++--- net/sunrpc/auth_gss/gss_krb5_mech.c | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) (limited to 'net/sunrpc/auth_gss') diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c index e7180da1fc6a..794fb3001880 100644 --- a/net/sunrpc/auth_gss/gss_krb5_crypto.c +++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c @@ -1003,7 +1003,7 @@ krb5_rc4_setup_seq_key(struct krb5_ctx *kctx, err = 0; out_err: - kzfree(desc); + kfree_sensitive(desc); crypto_free_shash(hmac); dprintk("%s: returning %d\n", __func__, err); return err; @@ -1079,7 +1079,7 @@ krb5_rc4_setup_enc_key(struct krb5_ctx *kctx, err = 0; out_err: - kzfree(desc); + kfree_sensitive(desc); crypto_free_shash(hmac); dprintk("%s: returning %d\n", __func__, err); return err; diff --git a/net/sunrpc/auth_gss/gss_krb5_keys.c b/net/sunrpc/auth_gss/gss_krb5_keys.c index 3b7f721c023b..726c076950c0 100644 --- a/net/sunrpc/auth_gss/gss_krb5_keys.c +++ b/net/sunrpc/auth_gss/gss_krb5_keys.c @@ -228,11 +228,11 @@ u32 krb5_derive_key(const struct gss_krb5_enctype *gk5e, ret = 0; err_free_raw: - kzfree(rawkey); + kfree_sensitive(rawkey); err_free_out: - kzfree(outblockdata); + kfree_sensitive(outblockdata); err_free_in: - kzfree(inblockdata); + kfree_sensitive(inblockdata); err_free_cipher: crypto_free_sync_skcipher(cipher); err_return: diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c index 75b3c2e9e8f8..a84a5b289484 100644 --- a/net/sunrpc/auth_gss/gss_krb5_mech.c +++ b/net/sunrpc/auth_gss/gss_krb5_mech.c @@ -443,7 +443,7 @@ context_derive_keys_rc4(struct krb5_ctx *ctx) desc->tfm = hmac; err = crypto_shash_digest(desc, sigkeyconstant, slen, ctx->cksum); - kzfree(desc); + kfree_sensitive(desc); if (err) goto out_err_free_hmac; /* -- cgit v1.2.3