Re: [PATCH] lib/crypto: aes: use memzero_explicit() instead of memset()

[Eric Biggers]

On Wed, Oct 28, 2026 at 07:56:36PM +0530, Mohamad Raizudeen wrote:
> aes_gcm_decrypt() and aes_ccm_decrypt() use plain memset() to wipe the
> output buffer when authentication fails. But the compiler can optimize
> that wipe away, so use memzero_explicit() instead of memset().
> 
> This matches every other sensitive wipes in this file, which already
> uses memzero_explicit() for keystream blocks, tmp buffers, ctx
> teardowns.
> 
> Signed-off-by: Mohamad Raizudeen <raizudeen.kerneldev@xxxxxxxxx>
> ---
>  lib/crypto/aes.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=libcrypto-next

I added the following note:

   [EB: I'm applying this mainly so this doesn't get flagged as an
        inconsistency again.  The main purpose of the zeroing here is just
        so the caller doesn't accidentally use the data, which a plain
        memset() is perfectly fine for. ]

- Eric