From 8db734f17e00765dfb78e314cbfa9d0cfbd47395 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@kernel.org>
Date: Thu, 4 Jul 2024 17:45:15 +0200
Subject: [PATCH] wireguard: allowedips: avoid unaligned 64-bit memory accesses

commit 948f991c62a4018fb81d85804eeab3029c6209f8 upstream.

On the parisc platform, the kernel issues kernel warnings because
swap_endian() tries to load a 128-bit IPv6 address from an unaligned
memory location:

 Kernel: unaligned access to 0x55f4688c in wg_allowedips_insert_v6+0x2c/0x80 [wireguard] (iir 0xf3010df)
 Kernel: unaligned access to 0x55f46884 in wg_allowedips_insert_v6+0x38/0x80 [wireguard] (iir 0xf2010dc)

Avoid such unaligned memory accesses by instead using the
get_unaligned_be64() helper macro.

Signed-off-by: Helge Deller <deller@gmx.de>
[Jason: replace src[8] in original patch with src+8]
Cc: stable@vger.kernel.org
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20240704154517.1572127-3-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/wireguard/allowedips.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireguard/allowedips.c b/drivers/net/wireguard/allowedips.c
index 0ba714ca5185c..4b8528206cc8a 100644
--- a/drivers/net/wireguard/allowedips.c
+++ b/drivers/net/wireguard/allowedips.c
@@ -15,8 +15,8 @@ static void swap_endian(u8 *dst, const u8 *src, u8 bits)
 	if (bits == 32) {
 		*(u32 *)dst = be32_to_cpu(*(const __be32 *)src);
 	} else if (bits == 128) {
-		((u64 *)dst)[0] = be64_to_cpu(((const __be64 *)src)[0]);
-		((u64 *)dst)[1] = be64_to_cpu(((const __be64 *)src)[1]);
+		((u64 *)dst)[0] = get_unaligned_be64(src);
+		((u64 *)dst)[1] = get_unaligned_be64(src + 8);
 	}
 }
 
-- 
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