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 --- lib/mpi/mpiutil.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib/mpi') diff --git a/lib/mpi/mpiutil.c b/lib/mpi/mpiutil.c index 20ed0f766787..4cd2b335cb7f 100644 --- a/lib/mpi/mpiutil.c +++ b/lib/mpi/mpiutil.c @@ -69,7 +69,7 @@ void mpi_free_limb_space(mpi_ptr_t a) if (!a) return; - kzfree(a); + kfree_sensitive(a); } void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs) @@ -95,7 +95,7 @@ int mpi_resize(MPI a, unsigned nlimbs) if (!p) return -ENOMEM; memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t)); - kzfree(a->d); + kfree_sensitive(a->d); a->d = p; } else { a->d = kcalloc(nlimbs, sizeof(mpi_limb_t), GFP_KERNEL); @@ -112,7 +112,7 @@ void mpi_free(MPI a) return; if (a->flags & 4) - kzfree(a->d); + kfree_sensitive(a->d); else mpi_free_limb_space(a->d); -- cgit v1.2.3