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 --- security/apparmor/domain.c | 4 ++-- security/apparmor/include/file.h | 2 +- security/apparmor/policy.c | 24 ++++++++++++------------ security/apparmor/policy_ns.c | 6 +++--- security/apparmor/policy_unpack.c | 14 +++++++------- 5 files changed, 25 insertions(+), 25 deletions(-) (limited to 'security/apparmor') diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index 1c898055a476..7b0e13ce7dc7 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -40,8 +40,8 @@ void aa_free_domain_entries(struct aa_domain *domain) return; for (i = 0; i < domain->size; i++) - kzfree(domain->table[i]); - kzfree(domain->table); + kfree_sensitive(domain->table[i]); + kfree_sensitive(domain->table); domain->table = NULL; } } diff --git a/security/apparmor/include/file.h b/security/apparmor/include/file.h index aff26fc71407..d4f8948517d9 100644 --- a/security/apparmor/include/file.h +++ b/security/apparmor/include/file.h @@ -72,7 +72,7 @@ static inline void aa_free_file_ctx(struct aa_file_ctx *ctx) { if (ctx) { aa_put_label(rcu_access_pointer(ctx->label)); - kzfree(ctx); + kfree_sensitive(ctx); } } diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index af4f50fda9e3..4c010c9a6af1 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -187,9 +187,9 @@ static void aa_free_data(void *ptr, void *arg) { struct aa_data *data = ptr; - kzfree(data->data); - kzfree(data->key); - kzfree(data); + kfree_sensitive(data->data); + kfree_sensitive(data->key); + kfree_sensitive(data); } /** @@ -217,19 +217,19 @@ void aa_free_profile(struct aa_profile *profile) aa_put_profile(rcu_access_pointer(profile->parent)); aa_put_ns(profile->ns); - kzfree(profile->rename); + kfree_sensitive(profile->rename); aa_free_file_rules(&profile->file); aa_free_cap_rules(&profile->caps); aa_free_rlimit_rules(&profile->rlimits); for (i = 0; i < profile->xattr_count; i++) - kzfree(profile->xattrs[i]); - kzfree(profile->xattrs); + kfree_sensitive(profile->xattrs[i]); + kfree_sensitive(profile->xattrs); for (i = 0; i < profile->secmark_count; i++) - kzfree(profile->secmark[i].label); - kzfree(profile->secmark); - kzfree(profile->dirname); + kfree_sensitive(profile->secmark[i].label); + kfree_sensitive(profile->secmark); + kfree_sensitive(profile->dirname); aa_put_dfa(profile->xmatch); aa_put_dfa(profile->policy.dfa); @@ -237,14 +237,14 @@ void aa_free_profile(struct aa_profile *profile) rht = profile->data; profile->data = NULL; rhashtable_free_and_destroy(rht, aa_free_data, NULL); - kzfree(rht); + kfree_sensitive(rht); } - kzfree(profile->hash); + kfree_sensitive(profile->hash); aa_put_loaddata(profile->rawdata); aa_label_destroy(&profile->label); - kzfree(profile); + kfree_sensitive(profile); } /** diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c index d7ef540027a5..70921d95fb40 100644 --- a/security/apparmor/policy_ns.c +++ b/security/apparmor/policy_ns.c @@ -121,9 +121,9 @@ static struct aa_ns *alloc_ns(const char *prefix, const char *name) return ns; fail_unconfined: - kzfree(ns->base.hname); + kfree_sensitive(ns->base.hname); fail_ns: - kzfree(ns); + kfree_sensitive(ns); return NULL; } @@ -145,7 +145,7 @@ void aa_free_ns(struct aa_ns *ns) ns->unconfined->ns = NULL; aa_free_profile(ns->unconfined); - kzfree(ns); + kfree_sensitive(ns); } /** diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index b67322abcc33..dc345ac93205 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -163,10 +163,10 @@ static void do_loaddata_free(struct work_struct *work) aa_put_ns(ns); } - kzfree(d->hash); - kzfree(d->name); + kfree_sensitive(d->hash); + kfree_sensitive(d->name); kvfree(d->data); - kzfree(d); + kfree_sensitive(d); } void aa_loaddata_kref(struct kref *kref) @@ -894,7 +894,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) while (unpack_strdup(e, &key, NULL)) { data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) { - kzfree(key); + kfree_sensitive(key); goto fail; } @@ -902,8 +902,8 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) data->size = unpack_blob(e, &data->data, NULL); data->data = kvmemdup(data->data, data->size); if (data->size && !data->data) { - kzfree(data->key); - kzfree(data); + kfree_sensitive(data->key); + kfree_sensitive(data); goto fail; } @@ -1037,7 +1037,7 @@ void aa_load_ent_free(struct aa_load_ent *ent) aa_put_profile(ent->old); aa_put_profile(ent->new); kfree(ent->ns_name); - kzfree(ent); + kfree_sensitive(ent); } } -- cgit v1.2.3