From: Ard Biesheuvel Date: Wed, 23 Oct 2019 09:50:44 +0000 (+0200) Subject: crypto: ecdh - fix big endian bug in ECC library X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e4895f5eac2622c46c73cc244b9991a768506c54;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git crypto: ecdh - fix big endian bug in ECC library commit f398243e9fd6a3a059c1ea7b380c40628dbf0c61 upstream. The elliptic curve arithmetic library used by the EC-DH KPP implementation assumes big endian byte order, and unconditionally reverses the byte and word order of multi-limb quantities. On big endian systems, the byte reordering is not necessary, while the word ordering needs to be retained. So replace the __swab64() invocation with a call to be64_to_cpu() which should do the right thing for both little and big endian builds. Fixes: 3c4b23901a0c ("crypto: ecdh - Add ECDH software support") Cc: # v4.9+ Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- diff --git a/crypto/ecc.c b/crypto/ecc.c index 414c78a9c214..7cf6c3e4825c 100644 --- a/crypto/ecc.c +++ b/crypto/ecc.c @@ -897,10 +897,11 @@ static void ecc_point_mult(struct ecc_point *result, static inline void ecc_swap_digits(const u64 *in, u64 *out, unsigned int ndigits) { + const __be64 *src = (__force __be64 *)in; int i; for (i = 0; i < ndigits; i++) - out[i] = __swab64(in[ndigits - 1 - i]); + out[i] = be64_to_cpu(src[ndigits - 1 - i]); } int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,