diff options
author | Waiman Long <longman@redhat.com> | 2020-08-07 08:18:13 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-07 20:33:22 +0200 |
commit | 453431a54934d917153c65211b2dabf45562ca88 (patch) | |
tree | e9672e7fb28f59331ff00fe6197360d703cbd9c3 /drivers/md | |
parent | ocfs2: fix unbalanced locking (diff) | |
download | linux-453431a54934d917153c65211b2dabf45562ca88.tar.xz linux-453431a54934d917153c65211b2dabf45562ca88.zip |
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 <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/dm-crypt.c | 32 | ||||
-rw-r--r-- | drivers/md/dm-integrity.c | 6 |
2 files changed, 19 insertions, 19 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index b437a14c4942..37dcc52cf21d 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -407,7 +407,7 @@ static void crypt_iv_lmk_dtr(struct crypt_config *cc) crypto_free_shash(lmk->hash_tfm); lmk->hash_tfm = NULL; - kzfree(lmk->seed); + kfree_sensitive(lmk->seed); lmk->seed = NULL; } @@ -558,9 +558,9 @@ static void crypt_iv_tcw_dtr(struct crypt_config *cc) { struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; - kzfree(tcw->iv_seed); + kfree_sensitive(tcw->iv_seed); tcw->iv_seed = NULL; - kzfree(tcw->whitening); + kfree_sensitive(tcw->whitening); tcw->whitening = NULL; if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) @@ -994,8 +994,8 @@ static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *d kunmap_atomic(data); out: - kzfree(ks); - kzfree(es); + kfree_sensitive(ks); + kfree_sensitive(es); skcipher_request_free(req); return r; } @@ -2294,7 +2294,7 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string key = request_key(type, key_desc + 1, NULL); if (IS_ERR(key)) { - kzfree(new_key_string); + kfree_sensitive(new_key_string); return PTR_ERR(key); } @@ -2304,7 +2304,7 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string if (ret < 0) { up_read(&key->sem); key_put(key); - kzfree(new_key_string); + kfree_sensitive(new_key_string); return ret; } @@ -2318,10 +2318,10 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string if (!ret) { set_bit(DM_CRYPT_KEY_VALID, &cc->flags); - kzfree(cc->key_string); + kfree_sensitive(cc->key_string); cc->key_string = new_key_string; } else - kzfree(new_key_string); + kfree_sensitive(new_key_string); return ret; } @@ -2382,7 +2382,7 @@ static int crypt_set_key(struct crypt_config *cc, char *key) clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); /* wipe references to any kernel keyring key */ - kzfree(cc->key_string); + kfree_sensitive(cc->key_string); cc->key_string = NULL; /* Decode key from its hex representation. */ @@ -2414,7 +2414,7 @@ static int crypt_wipe_key(struct crypt_config *cc) return r; } - kzfree(cc->key_string); + kfree_sensitive(cc->key_string); cc->key_string = NULL; r = crypt_setkey(cc); memset(&cc->key, 0, cc->key_size * sizeof(u8)); @@ -2493,15 +2493,15 @@ static void crypt_dtr(struct dm_target *ti) if (cc->dev) dm_put_device(ti, cc->dev); - kzfree(cc->cipher_string); - kzfree(cc->key_string); - kzfree(cc->cipher_auth); - kzfree(cc->authenc_key); + kfree_sensitive(cc->cipher_string); + kfree_sensitive(cc->key_string); + kfree_sensitive(cc->cipher_auth); + kfree_sensitive(cc->authenc_key); mutex_destroy(&cc->bio_alloc_lock); /* Must zero key material before freeing */ - kzfree(cc); + kfree_sensitive(cc); spin_lock(&dm_crypt_clients_lock); WARN_ON(!dm_crypt_clients_n); diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 5da3eb661e50..8c8d940e532e 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -3405,8 +3405,8 @@ static struct scatterlist **dm_integrity_alloc_journal_scatterlist(struct dm_int static void free_alg(struct alg_spec *a) { - kzfree(a->alg_string); - kzfree(a->key); + kfree_sensitive(a->alg_string); + kfree_sensitive(a->key); memset(a, 0, sizeof *a); } @@ -4337,7 +4337,7 @@ static void dm_integrity_dtr(struct dm_target *ti) for (i = 0; i < ic->journal_sections; i++) { struct skcipher_request *req = ic->sk_requests[i]; if (req) { - kzfree(req->iv); + kfree_sensitive(req->iv); skcipher_request_free(req); } } |