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author | Waiman Long <longman@redhat.com> | 2020-08-06 23:18:13 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-07 11:33:22 -0700 |
commit | 453431a54934d917153c65211b2dabf45562ca88 (patch) | |
tree | e9672e7fb28f59331ff00fe6197360d703cbd9c3 /include | |
parent | 57c720d4144a9c2b88105c3e8f7b0e97e4b5cc93 (diff) | |
download | linux-stable-453431a54934d917153c65211b2dabf45562ca88.tar.gz linux-stable-453431a54934d917153c65211b2dabf45562ca88.tar.bz2 linux-stable-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 'include')
-rw-r--r-- | include/crypto/aead.h | 2 | ||||
-rw-r--r-- | include/crypto/akcipher.h | 2 | ||||
-rw-r--r-- | include/crypto/gf128mul.h | 2 | ||||
-rw-r--r-- | include/crypto/hash.h | 2 | ||||
-rw-r--r-- | include/crypto/internal/acompress.h | 2 | ||||
-rw-r--r-- | include/crypto/kpp.h | 2 | ||||
-rw-r--r-- | include/crypto/skcipher.h | 2 | ||||
-rw-r--r-- | include/linux/slab.h | 4 |
8 files changed, 10 insertions, 8 deletions
diff --git a/include/crypto/aead.h b/include/crypto/aead.h index 62c68550aab6..c32a6f5664e9 100644 --- a/include/crypto/aead.h +++ b/include/crypto/aead.h @@ -425,7 +425,7 @@ static inline struct aead_request *aead_request_alloc(struct crypto_aead *tfm, */ static inline void aead_request_free(struct aead_request *req) { - kzfree(req); + kfree_sensitive(req); } /** diff --git a/include/crypto/akcipher.h b/include/crypto/akcipher.h index 6924b091adec..1d3aa252caba 100644 --- a/include/crypto/akcipher.h +++ b/include/crypto/akcipher.h @@ -207,7 +207,7 @@ static inline struct akcipher_request *akcipher_request_alloc( */ static inline void akcipher_request_free(struct akcipher_request *req) { - kzfree(req); + kfree_sensitive(req); } /** diff --git a/include/crypto/gf128mul.h b/include/crypto/gf128mul.h index fa0a63d298dc..81330c6446f6 100644 --- a/include/crypto/gf128mul.h +++ b/include/crypto/gf128mul.h @@ -230,7 +230,7 @@ void gf128mul_4k_bbe(be128 *a, const struct gf128mul_4k *t); void gf128mul_x8_ble(le128 *r, const le128 *x); static inline void gf128mul_free_4k(struct gf128mul_4k *t) { - kzfree(t); + kfree_sensitive(t); } diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 19ce91f2359f..0d1b403888c9 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -606,7 +606,7 @@ static inline struct ahash_request *ahash_request_alloc( */ static inline void ahash_request_free(struct ahash_request *req) { - kzfree(req); + kfree_sensitive(req); } static inline void ahash_request_zero(struct ahash_request *req) diff --git a/include/crypto/internal/acompress.h b/include/crypto/internal/acompress.h index cf478681b53e..cfc47e18820f 100644 --- a/include/crypto/internal/acompress.h +++ b/include/crypto/internal/acompress.h @@ -46,7 +46,7 @@ static inline struct acomp_req *__acomp_request_alloc(struct crypto_acomp *tfm) static inline void __acomp_request_free(struct acomp_req *req) { - kzfree(req); + kfree_sensitive(req); } /** diff --git a/include/crypto/kpp.h b/include/crypto/kpp.h index cd9a9b500624..88b591215d5c 100644 --- a/include/crypto/kpp.h +++ b/include/crypto/kpp.h @@ -187,7 +187,7 @@ static inline struct kpp_request *kpp_request_alloc(struct crypto_kpp *tfm, */ static inline void kpp_request_free(struct kpp_request *req) { - kzfree(req); + kfree_sensitive(req); } /** diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h index 5663f71198b3..6a733b171a5d 100644 --- a/include/crypto/skcipher.h +++ b/include/crypto/skcipher.h @@ -508,7 +508,7 @@ static inline struct skcipher_request *skcipher_request_alloc( */ static inline void skcipher_request_free(struct skcipher_request *req) { - kzfree(req); + kfree_sensitive(req); } static inline void skcipher_request_zero(struct skcipher_request *req) diff --git a/include/linux/slab.h b/include/linux/slab.h index 6d454886bcaf..0884d82c55ee 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -186,10 +186,12 @@ void memcg_deactivate_kmem_caches(struct mem_cgroup *, struct mem_cgroup *); */ void * __must_check krealloc(const void *, size_t, gfp_t); void kfree(const void *); -void kzfree(const void *); +void kfree_sensitive(const void *); size_t __ksize(const void *); size_t ksize(const void *); +#define kzfree(x) kfree_sensitive(x) /* For backward compatibility */ + #ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR void __check_heap_object(const void *ptr, unsigned long n, struct page *page, bool to_user); |