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 --- drivers/crypto/ccree/cc_cipher.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/crypto/ccree/cc_cipher.c') diff --git a/drivers/crypto/ccree/cc_cipher.c b/drivers/crypto/ccree/cc_cipher.c index 076669dc1035..d77ae981b64b 100644 --- a/drivers/crypto/ccree/cc_cipher.c +++ b/drivers/crypto/ccree/cc_cipher.c @@ -257,7 +257,7 @@ static void cc_cipher_exit(struct crypto_tfm *tfm) &ctx_p->user.key_dma_addr); /* Free key buffer in context */ - kzfree(ctx_p->user.key); + kfree_sensitive(ctx_p->user.key); dev_dbg(dev, "Free key buffer in context. key=@%p\n", ctx_p->user.key); } @@ -881,7 +881,7 @@ static void cc_cipher_complete(struct device *dev, void *cc_req, int err) /* Not a BACKLOG notification */ cc_unmap_cipher_request(dev, req_ctx, ivsize, src, dst); memcpy(req->iv, req_ctx->iv, ivsize); - kzfree(req_ctx->iv); + kfree_sensitive(req_ctx->iv); } skcipher_request_complete(req, err); @@ -994,7 +994,7 @@ static int cc_cipher_process(struct skcipher_request *req, exit_process: if (rc != -EINPROGRESS && rc != -EBUSY) { - kzfree(req_ctx->iv); + kfree_sensitive(req_ctx->iv); } return rc; -- cgit v1.2.3-59-g8ed1b