[PATCH v4 0/3] mm, treewide: Rename kzfree() to kfree_sensitive()

Joe Perches joe at perches.com
Tue Jun 16 18:53:50 UTC 2020


On Mon, 2020-06-15 at 21:57 -0400, Waiman Long wrote:
>  v4:
>   - Break out the memzero_explicit() change as suggested by Dan Carpenter
>     so that it can be backported to stable.
>   - Drop the "crypto: Remove unnecessary memzero_explicit()" patch for
>     now as there can be a bit more discussion on what is best. It will be
>     introduced as a separate patch later on after this one is merged.

To this larger audience and last week without reply:
https://lore.kernel.org/lkml/573b3fbd5927c643920e1364230c296b23e7584d.camel@perches.com/

Are there _any_ fastpath uses of kfree or vfree?

Many patches have been posted recently to fix mispairings
of specific types of alloc and free functions.

To eliminate these mispairings at a runtime cost of four
comparisons, should the kfree/vfree/kvfree/kfree_const
functions be consolidated into a single kfree?

Something like the below:

   void kfree(const void *addr)
   {
   	if (is_kernel_rodata((unsigned long)addr))
   		return;

   	if (is_vmalloc_addr(addr))
   		_vfree(addr);
   	else
   		_kfree(addr);
   }

   #define kvfree		kfree
   #define vfree		kfree
   #define kfree_const	kfree




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