kernel: 5.4: import wireguard backport

Rather than using the clunky, old, slower wireguard-linux-compat out of
tree module, this commit does a patch-by-patch backport of upstream's
wireguard to 5.4. This specific backport is in widespread use, being
part of SUSE's enterprise kernel, Oracle's enterprise kernel, Google's
Android kernel, Gentoo's distro kernel, and probably more I've forgotten
about. It's definately the "more proper" way of adding wireguard to a
kernel than the ugly compat.h hell of the wireguard-linux-compat repo.
And most importantly for OpenWRT, it allows using the same module
configuration code for 5.10 as for 5.4, with no need for bifurcation.

These patches are from the backport tree which is maintained in the
open here: https://git.zx2c4.com/wireguard-linux/log/?h=backport-5.4.y
I'll be sending PRs to update this as needed.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/080-wireguard-0066-crypto-x86-poly1305-add-back-a-needed-assignment.patch b/target/linux/generic/backport-5.4/080-wireguard-0066-crypto-x86-poly1305-add-back-a-needed-assignment.patch
new file mode 100644
index 0000000000..aebedb0282
--- /dev/null
+++ b/target/linux/generic/backport-5.4/080-wireguard-0066-crypto-x86-poly1305-add-back-a-needed-assignment.patch
@@ -0,0 +1,33 @@
+From 4849474f7e021d0d2e33a008abf93cacebf812f4 Mon Sep 17 00:00:00 2001
+From: Eric Biggers <ebiggers@google.com>
+Date: Fri, 23 Oct 2020 15:27:48 -0700
+Subject: [PATCH 066/124] crypto: x86/poly1305 - add back a needed assignment
+
+commit c3a98c3ad5c0dc60a1ac66bf91147a3f39cac96b upstream.
+
+One of the assignments that was removed by commit 4a0c1de64bf9 ("crypto:
+x86/poly1305 - Remove assignments with no effect") is actually needed,
+since it affects the return value.
+
+This fixes the following crypto self-test failure:
+
+    alg: shash: poly1305-simd test failed (wrong result) on test vector 2, cfg="init+update+final aligned buffer"
+
+Fixes: 4a0c1de64bf9 ("crypto: x86/poly1305 - Remove assignments with no effect")
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+---
+ arch/x86/crypto/poly1305_glue.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/arch/x86/crypto/poly1305_glue.c
++++ b/arch/x86/crypto/poly1305_glue.c
+@@ -157,6 +157,7 @@ static unsigned int crypto_poly1305_setd
+ 			dctx->s[1] = get_unaligned_le32(&inp[4]);
+ 			dctx->s[2] = get_unaligned_le32(&inp[8]);
+ 			dctx->s[3] = get_unaligned_le32(&inp[12]);
++			acc += POLY1305_BLOCK_SIZE;
+ 			dctx->sset = true;
+ 		}
+ 	}