crypto: arm/neon - memzero_explicit aes-cbc key

At function exit, do not leave the expanded key in the rk struct
which got allocated on the stack.

Signed-off-by: Torsten Duwe <[e-mail]>
Acked-by: Will Deacon <[e-mail]>
Acked-by: Ard Biesheuvel <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

arch/arm/crypto/aes-neonbs-glue.c

···
 	kernel_neon_begin();
 	aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds);
 	kernel_neon_end();
+	memzero_explicit(&rk, sizeof(rk));
 
 	return crypto_cipher_setkey(ctx->enc_tfm, in_key, key_len);
 }

arch/arm64/crypto/aes-neonbs-glue.c

···
 	kernel_neon_begin();
 	aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds);
 	kernel_neon_end();
+	memzero_explicit(&rk, sizeof(rk));
 
 	return 0;
 }