From 8e6d97c5b01df9b069f8a32d104d57cde92c96aa Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 23 Oct 2019 11:50:44 +0200 Subject: [PATCH] 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 --- crypto/ecc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/crypto/ecc.c b/crypto/ecc.c index dfe114bc0c4a..8ee787723c5c 100644 --- a/crypto/ecc.c +++ b/crypto/ecc.c @@ -1284,10 +1284,11 @@ EXPORT_SYMBOL(ecc_point_mult_shamir); 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]); } static int __ecc_is_key_valid(const struct ecc_curve *curve,