Re: [PATCH 1/2] crypto: fix dependencies on lib/crypto modules

[Eric Biggers <ebiggers@kernel.org>]

On Mon, Mar 10, 2025 at 02:26:39PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The crypto subsystem helpers for chacha, poly1305 and curve25519 were
> changed to select the 'INTERNAL' Kconfig symbols, but the code references
> the generic implementation instead, which leads to a link failure when
> nothing else selects it.
> 
> ld.lld-21: error: undefined symbol: chacha_crypt_generic
> >>> referenced by chacha_generic.c
> >>>               crypto/chacha_generic.o:(chacha_stream_xor) in archive vmlinux.a
> 
> ld.lld-21: error: undefined symbol: poly1305_final_generic
> >>> referenced by poly1305_generic.c
> >>>               crypto/poly1305_generic.o:(crypto_poly1305_final) in archive vmlinux.a
> 
> The INTERNAL version turns on the architecture specific optimized cipher,
> which normally usually also enables the generic version, but this is not
> the case on all architectures. Selecting only the GENERIC version here is
> not sufficient since the architecture specific ones are now hidden symbols
> and are only built when the INTERNAL symbol is also available.
> 
> Fixes: 17ec3e71ba79 ("crypto: lib/Kconfig - Hide arch options from user")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  crypto/Kconfig | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/crypto/Kconfig b/crypto/Kconfig
> index aac27a4668fd..76693e3edff8 100644
> --- a/crypto/Kconfig
> +++ b/crypto/Kconfig
> @@ -317,6 +317,7 @@ config CRYPTO_ECRDSA
>  config CRYPTO_CURVE25519
>  	tristate "Curve25519"
>  	select CRYPTO_KPP
> +	select CRYPTO_LIB_CURVE25519_GENERIC
>  	select CRYPTO_LIB_CURVE25519_INTERNAL
>  	help
>  	  Curve25519 elliptic curve (RFC7748)
> @@ -615,6 +616,7 @@ config CRYPTO_ARC4
>  
>  config CRYPTO_CHACHA20
>  	tristate "ChaCha"
> +	select CRYPTO_LIB_CHACHA_GENERIC
>  	select CRYPTO_LIB_CHACHA_INTERNAL
>  	select CRYPTO_SKCIPHER
>  	help
> @@ -936,6 +938,7 @@ config CRYPTO_POLYVAL
>  config CRYPTO_POLY1305
>  	tristate "Poly1305"
>  	select CRYPTO_HASH
> +	select CRYPTO_LIB_POLY1305_GENERIC
>  	select CRYPTO_LIB_POLY1305_INTERNAL
>  	help
>  	  Poly1305 authenticator algorithm (RFC7539)

Looks the same as
https://lore.kernel.org/linux-crypto/Z8UdUoaKtDKzgPph@gondor.apana.org.au/ which
was already applied.

- Eric