crypto: memneq - move into lib/

commit abfed87e2a12bd246047d78c01d81eb9529f1d06 upstream.

This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a linker error Zheng pointed out when
CRYPTO_MANAGER_DISABLE_TESTS!=y and CRYPTO=m:

  lib/crypto/curve25519-selftest.o: In function `curve25519_selftest':
  curve25519-selftest.c:(.init.text+0x60): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0xec): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x114): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x154): undefined reference to `__crypto_memneq'

Reported-by: Zheng Bin <zhengbin13@huawei.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: stable@vger.kernel.org
Fixes: aa127963f1ca ("crypto: lib/curve25519 - re-add selftests")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/crypto/Kconfig b/crypto/Kconfig
index c15bfc0e3723..4a53cb98f3df 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -15,6 +15,7 @@ source "crypto/async_tx/Kconfig"
 #
 menuconfig CRYPTO
 	tristate "Cryptographic API"
+	select LIB_MEMNEQ
 	help
 	  This option provides the core Cryptographic API.