Merge branch 'wireguard-fixes-for-6-10-rc7'

Jason A. Donenfeld says:

====================
wireguard fixes for 6.10-rc7

These are four small fixes for WireGuard, which are all marked for
stable:

1) A QEMU command line fix to remove deprecated flags.

2) Use of proper unaligned helpers to avoid unaligned memory access on
   some systems, from Helge.

3) Two patches to annotate intentional data races, so KCSAN and syzbot
   don't get upset.
====================

Link: https://patch.msgid.link/20240704154517.1572127-1-Jason@zx2c4.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

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);
 	}
 }
 

drivers/net/wireguard/queueing.h

@@ -124,10 +124,10 @@ static inline int wg_cpumask_choose_online(int *stored_cpu, unsigned int id)
  */
 static inline int wg_cpumask_next_online(int *last_cpu)
 {
-	int cpu = cpumask_next(*last_cpu, cpu_online_mask);
+	int cpu = cpumask_next(READ_ONCE(*last_cpu), cpu_online_mask);
 	if (cpu >= nr_cpu_ids)
 		cpu = cpumask_first(cpu_online_mask);
-	*last_cpu = cpu;
+	WRITE_ONCE(*last_cpu, cpu);
 	return cpu;
 }
 

drivers/net/wireguard/send.c

@@ -222,7 +222,7 @@ void wg_packet_send_keepalive(struct wg_peer *peer)
 {
 	struct sk_buff *skb;
 
-	if (skb_queue_empty(&peer->staged_packet_queue)) {
+	if (skb_queue_empty_lockless(&peer->staged_packet_queue)) {
 		skb = alloc_skb(DATA_PACKET_HEAD_ROOM + MESSAGE_MINIMUM_LENGTH,
 				GFP_ATOMIC);
 		if (unlikely(!skb))

tools/testing/selftests/wireguard/qemu/Makefile

@@ -109,9 +109,9 @@ KERNEL_ARCH := x86_64
 KERNEL_BZIMAGE := $(KERNEL_BUILD_PATH)/arch/x86/boot/bzImage
 QEMU_VPORT_RESULT := virtio-serial-device
 ifeq ($(HOST_ARCH),$(ARCH))
-QEMU_MACHINE := -cpu host -machine microvm,accel=kvm,pit=off,pic=off,rtc=off -no-acpi
+QEMU_MACHINE := -cpu host -machine microvm,accel=kvm,pit=off,pic=off,rtc=off,acpi=off
 else
-QEMU_MACHINE := -cpu max -machine microvm -no-acpi
+QEMU_MACHINE := -cpu max -machine microvm,acpi=off
 endif
 else ifeq ($(ARCH),i686)
 CHOST := i686-linux-musl
@@ -120,9 +120,9 @@ KERNEL_ARCH := x86
 KERNEL_BZIMAGE := $(KERNEL_BUILD_PATH)/arch/x86/boot/bzImage
 QEMU_VPORT_RESULT := virtio-serial-device
 ifeq ($(subst x86_64,i686,$(HOST_ARCH)),$(ARCH))
-QEMU_MACHINE := -cpu host -machine microvm,accel=kvm,pit=off,pic=off,rtc=off -no-acpi
+QEMU_MACHINE := -cpu host -machine microvm,accel=kvm,pit=off,pic=off,rtc=off,acpi=off
 else
-QEMU_MACHINE := -cpu coreduo -machine microvm -no-acpi
+QEMU_MACHINE := -cpu coreduo -machine microvm,acpi=off
 endif
 else ifeq ($(ARCH),mips64)
 CHOST := mips64-linux-musl