From patchwork Thu Jul 4 15:45:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13723931 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F39F1E861; Thu, 4 Jul 2024 15:45:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107940; cv=none; b=unDL0fp3mnDF/yDkL3g4WAaSbjVLGhETo231K1L3Qw41EQhJLgF7Q2MdTUkYErIoiFDY58D8+YIltRIA1Fmvjg4jczz8+5oV8w0d/dssyIjO4MhmfXcEzogCBGlC5CAGVQfVadvVveFaKBr/y+2liJ76v7URi7uXVfWgcd14o4k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107940; c=relaxed/simple; bh=ABMVNkvqtrZ/U1ZII4FD6j1jgFGa98djSfjOO8yic2s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jOcLPn+/5+2YV3CmWxJw+Q8bbe1DIZ6oDRyrZbB2hnyAyr/DTd0NlHxmmUWHGG01rc4pTh5Etbz2WlzP3T6XI+qmxTPwj+VHw1rPAfl0B6nIkhOaMPDHacDU7hlwuVkgEXfTwQYlwcGpri1LmWOBEUvuA3B6QvwTtM1hkb4M/tE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b=nEoQnD2c; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="nEoQnD2c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1963C4AF0A; Thu, 4 Jul 2024 15:45:39 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="nEoQnD2c" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1720107938; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tdPYOGd7uDAvF3bTb+aC67tpnJm2eaZYe1/JFj22kaM=; b=nEoQnD2c9hmwTsMxhnC/R7KzPcrRe4p3eWpJm22zEM5xsztcrCDo2MtrSDL2gFpNxHVlqq m6xxUAsOAfqQ9bZIj2vyxGPxrfFiDnC9KdjwfEzDvCz3oCkei7jygIjNjnjWBLlOBGwCgq OtsE7rhXh4NwoP8JR4L0JMYJw2heJ44= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id dde21d07 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 4 Jul 2024 15:45:38 +0000 (UTC) From: "Jason A. Donenfeld" To: netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org Cc: "Jason A. Donenfeld" , stable@vger.kernel.org Subject: [PATCH net 1/4] wireguard: selftests: use acpi=off instead of -no-acpi for recent QEMU Date: Thu, 4 Jul 2024 17:45:14 +0200 Message-ID: <20240704154517.1572127-2-Jason@zx2c4.com> In-Reply-To: <20240704154517.1572127-1-Jason@zx2c4.com> References: <20240704154517.1572127-1-Jason@zx2c4.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org QEMU 9.0 removed -no-acpi, in favor of machine properties, so update the Makefile to use the correct QEMU invocation. Cc: stable@vger.kernel.org Fixes: b83fdcd9fb8a ("wireguard: selftests: use microvm on x86") Signed-off-by: Jason A. Donenfeld --- tools/testing/selftests/wireguard/qemu/Makefile | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/wireguard/qemu/Makefile b/tools/testing/selftests/wireguard/qemu/Makefile index e95bd56b332f..35856b11c143 100644 --- a/tools/testing/selftests/wireguard/qemu/Makefile +++ b/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 From patchwork Thu Jul 4 15:45:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13723932 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C21F91E861; Thu, 4 Jul 2024 15:45:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107942; cv=none; b=JYf/mUStkLO5LfV4fSZ9Y/PV19DV/Jce42l3UFw93/RXTppJvPHudORb+KTqTuUrCzSYebnl05pBhPbSPJg8R5D9LwPyaz7AxSoLChydLtj9IE98tZFjGt6+/Ykv9i+QYSAmaRC31B/75n/iVfRuUqoZT/zTL12HbdGtHyt0d6M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107942; c=relaxed/simple; bh=egf/NogojxYlVhbIl36DFaMxrtmn9gD2oDV/ECsv8+M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=StNWviyFAimRClvAYMmTjymlwt1DQppLZNteV8aUjBbnauHLYV/ZaQ2gHOLzR6YzYwC1sMJfg4Rt7h+TihGBuz61OLCXstQ9qzVbXoYMW0dQ0ynPYX2w4JKUDDgKhu39bFOCyjPLZ1sbHR5p4bfpW5wGuh/nUkZFeXMtNvp7Yto= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b=oQ2x3qwm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="oQ2x3qwm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98762C3277B; Thu, 4 Jul 2024 15:45:41 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="oQ2x3qwm" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1720107941; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yKo+ZyGaQ2EoSeO4/oIDVU7iVMp8bIw2iMxwxEC2mbI=; b=oQ2x3qwm1WACbQg8j0p1vcmrlVqYZx2Fp7ILKojgUgtX8nWj++ozTUF0fO50JkyT4xSVOa 8MreIRzXF5i87DjeU1Zn8jseSm8YpKeTF3lqiNclBAwyTPy6tCMVR43HS0aeiOjwo+Lk4F mNC/KFlzLUXeKffqWn91j+8QOvm0pVM= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 66ec19bf (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 4 Jul 2024 15:45:40 +0000 (UTC) From: "Jason A. Donenfeld" To: netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org Cc: Helge Deller , Helge Deller , stable@vger.kernel.org, "Jason A . Donenfeld" Subject: [PATCH net 2/4] wireguard: allowedips: avoid unaligned 64-bit memory accesses Date: Thu, 4 Jul 2024 17:45:15 +0200 Message-ID: <20240704154517.1572127-3-Jason@zx2c4.com> In-Reply-To: <20240704154517.1572127-1-Jason@zx2c4.com> References: <20240704154517.1572127-1-Jason@zx2c4.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org From: Helge Deller 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 [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 --- 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 0ba714ca5185..4b8528206cc8 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); } } From patchwork Thu Jul 4 15:45:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13723933 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 24DCA1BC23; Thu, 4 Jul 2024 15:45:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107945; cv=none; b=lw7o8OpdfcUrvxMJl2jKSa9prFycYfxp313vPCdJi+2p2DBcmQykNdC361D4kRMeUzRm17zt/dmoJFMNeV9HOyFGABm/7dUBWZimfisQzWmrXgqgwiVRz1SLzeBKl1EkcdbqDrUmiX3jw4oubbC88hnQxV9IuzPo/1/0zAHdAxE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107945; c=relaxed/simple; bh=oJBlWbPqZo8nujkVn1QJfVZCnw4HNFGE9kS3+dueDfQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bfCnA1tYBpkQVBJ+Qta68JUBZUCkTAsIy/XVwkd3DOOFLGlpocefEcg+xvMLWFefzvDVzGHlWBC8dH9E9GAZEf45vJ6Kwk1Cq6NyK+jMge0AwI/QbLyojCdCpc5SJYUr6kT5z6hC6ye/CqBF0LSfLWJQ3HkUC0gsRHVNRrKR1MM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b=Zp1Q88pS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="Zp1Q88pS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78B19C3277B; Thu, 4 Jul 2024 15:45:44 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="Zp1Q88pS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1720107943; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7byKffxEApbn+yt6bUXHpSYmYpStI6tw/7/MBTMtZ28=; b=Zp1Q88pSBmynJxy+NV2xE97GYwRUQReEwdTL15lyZzxSqTX7en+vRaWNOgHzsn0REDEdmk ocV8xYOAZt7smSlaMiXhQqSmoULI/mrwET0lCJ771bu/a+zbm3p2Zt7N5qJtk4rhjNarcp xKD4ZxuYO/VZWtbPbQWg1tu5BHtcpk4= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 5cb51d87 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 4 Jul 2024 15:45:43 +0000 (UTC) From: "Jason A. Donenfeld" To: netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org Cc: "Jason A. Donenfeld" , stable@vger.kernel.org Subject: [PATCH net 3/4] wireguard: queueing: annotate intentional data race in cpu round robin Date: Thu, 4 Jul 2024 17:45:16 +0200 Message-ID: <20240704154517.1572127-4-Jason@zx2c4.com> In-Reply-To: <20240704154517.1572127-1-Jason@zx2c4.com> References: <20240704154517.1572127-1-Jason@zx2c4.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org KCSAN reports a race in the CPU round robin function, which, as the comment points out, is intentional: BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets read to 0xffff88811254eb28 of 4 bytes by task 3160 on cpu 1: wg_cpumask_next_online drivers/net/wireguard/queueing.h:127 [inline] wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:173 [inline] wg_packet_create_data drivers/net/wireguard/send.c:320 [inline] wg_packet_send_staged_packets+0x60e/0xac0 drivers/net/wireguard/send.c:388 wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline] wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213 process_one_work kernel/workqueue.c:3248 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3329 worker_thread+0x526/0x720 kernel/workqueue.c:3409 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 write to 0xffff88811254eb28 of 4 bytes by task 3158 on cpu 0: wg_cpumask_next_online drivers/net/wireguard/queueing.h:130 [inline] wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:173 [inline] wg_packet_create_data drivers/net/wireguard/send.c:320 [inline] wg_packet_send_staged_packets+0x6e5/0xac0 drivers/net/wireguard/send.c:388 wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline] wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213 process_one_work kernel/workqueue.c:3248 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3329 worker_thread+0x526/0x720 kernel/workqueue.c:3409 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 value changed: 0xffffffff -> 0x00000000 Mark this race as intentional by using READ/WRITE_ONCE(). Cc: stable@vger.kernel.org Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld --- drivers/net/wireguard/queueing.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireguard/queueing.h b/drivers/net/wireguard/queueing.h index 1ea4f874e367..7eb76724b3ed 100644 --- a/drivers/net/wireguard/queueing.h +++ b/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; } From patchwork Thu Jul 4 15:45:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13723934 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 459221BC23; Thu, 4 Jul 2024 15:45:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107947; cv=none; b=Wwr5nhyVGtk9lEHVvYt9NonbtHogJ6h7hf6Omg25qooSamlw3ECR20WsJ4F5PQy5sQLN9EdOAMoKZ1KlvpxDk+kU7ZZLcLum3I8lWauLRlTGKlDP0BNZE5fGnuc6NhduhH2+tze346CKortsXl8ll7x1zicNobmvk7a1MZw7+IU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720107947; c=relaxed/simple; bh=N5AkLMKAj0SpjYMWLW+TY358kBxOwj9aAQ2DTIVzOWY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WBehUHK8UPE0gvixkErmJviFnPtnLYV1aLGFS876OPyxIgU/OYV8+Yo/sdhgEdC21ZdUfYlIyG/ZHHJSQpYeu3iga31PfIAUaNMMRh/CYcCdcAzt1GSHyNKkR4hu9GKt9gBGN8n+T7eePbXlgdR5DvNoR88nUuQBOnoj+m5hnL0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b=e9WtA3S/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="e9WtA3S/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EA14C4AF0C; Thu, 4 Jul 2024 15:45:46 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="e9WtA3S/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1720107945; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Q2UjGiL+UGoWpQUK5mIzDE+VPqWH2b/EH1cM5yf2OCQ=; b=e9WtA3S/rQ0zTi+DCGL23euj1kVtBz5jB5pAw9P/DM8pfR6t39hkw4kSM3RRAX3qYKrQQY GP0Y+S7Fj1P6hxKdBlfu6mPlFaPYDo4B+u2dPVvAOf0F3iygVB94evjyBxSAYPNKq0nfuL KxdWJEEaVdz38oFBsgUUIJpQI4Gu/5M= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id d2486546 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 4 Jul 2024 15:45:45 +0000 (UTC) From: "Jason A. Donenfeld" To: netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org Cc: "Jason A. Donenfeld" , stable@vger.kernel.org Subject: [PATCH net 4/4] wireguard: send: annotate intentional data race in checking empty queue Date: Thu, 4 Jul 2024 17:45:17 +0200 Message-ID: <20240704154517.1572127-5-Jason@zx2c4.com> In-Reply-To: <20240704154517.1572127-1-Jason@zx2c4.com> References: <20240704154517.1572127-1-Jason@zx2c4.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org KCSAN reports a race in wg_packet_send_keepalive, which is intentional: BUG: KCSAN: data-race in wg_packet_send_keepalive / wg_packet_send_staged_packets write to 0xffff88814cd91280 of 8 bytes by task 3194 on cpu 0: __skb_queue_head_init include/linux/skbuff.h:2162 [inline] skb_queue_splice_init include/linux/skbuff.h:2248 [inline] wg_packet_send_staged_packets+0xe5/0xad0 drivers/net/wireguard/send.c:351 wg_xmit+0x5b8/0x660 drivers/net/wireguard/device.c:218 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3564 __dev_queue_xmit+0xeff/0x1d80 net/core/dev.c:4349 dev_queue_xmit include/linux/netdevice.h:3134 [inline] neigh_connected_output+0x231/0x2a0 net/core/neighbour.c:1592 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xa66/0xce0 net/ipv6/ip6_output.c:137 ip6_finish_output+0x1a5/0x490 net/ipv6/ip6_output.c:222 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0xeb/0x220 net/ipv6/ip6_output.c:243 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0x4a2/0x670 net/ipv6/ndisc.c:509 ndisc_send_rs+0x3ab/0x3e0 net/ipv6/ndisc.c:719 addrconf_dad_completed+0x640/0x8e0 net/ipv6/addrconf.c:4295 addrconf_dad_work+0x891/0xbc0 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706 worker_thread+0x525/0x730 kernel/workqueue.c:2787 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 read to 0xffff88814cd91280 of 8 bytes by task 3202 on cpu 1: skb_queue_empty include/linux/skbuff.h:1798 [inline] wg_packet_send_keepalive+0x20/0x100 drivers/net/wireguard/send.c:225 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline] wg_packet_handshake_receive_worker+0x445/0x5e0 drivers/net/wireguard/receive.c:213 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706 worker_thread+0x525/0x730 kernel/workqueue.c:2787 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 value changed: 0xffff888148fef200 -> 0xffff88814cd91280 Mark this race as intentional by using the skb_queue_empty_lockless() function rather than skb_queue_empty(), which uses READ_ONCE() internally to annotate the race. Cc: stable@vger.kernel.org Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld --- drivers/net/wireguard/send.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireguard/send.c b/drivers/net/wireguard/send.c index 0d48e0f4a1ba..26e09c30d596 100644 --- a/drivers/net/wireguard/send.c +++ b/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))