From patchwork Thu Mar 14 14:18:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 13592484 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C9FD6FE06 for ; Thu, 14 Mar 2024 14:18:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710425901; cv=none; b=ZyUChXooJxkO22iarFL4LNhGW0L721le6E+Sbc3NKt0bxsGWfyPAj0Oqq8pGrRmu2832hpeeVVmt+Fc/8PVLasdn3qW5DpjjOTKuofO331hf+11zB7xkBSryM5s0mGQDcES5KSfhdspoAN1JZME5xMaEBklPOPeovIxPOBqIxPw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710425901; c=relaxed/simple; bh=pjP4WENKr8rRaajWGUR/ri4zzoAy8yOgOfShfJkKBWo=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=EZVKKrF2vE1uesjTpeMnJUymKY7yr1C7+IQwdb9Bs7gkF8hQORjcu/aswSLapsJvPQBxqtwFWyHzr6k9Gupy32atmfjS5E1ZwhRng075xgwcKpH8XKEJmzsiURjDtObjY1bdZfp0Si8WPZczvA782AVXOzfbbe8bpFxJv/Iymjs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=CTePn8kx; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CTePn8kx" Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dbf216080f5so1412273276.1 for ; Thu, 14 Mar 2024 07:18:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1710425898; x=1711030698; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=BZp9l6e5lWy9HD+MMXNWuQUDngomkZLkCLaBGKO4JoY=; b=CTePn8kx3Shpm+vEBEzTN8rInAwEbqFWdiZojZPw2ji7O+JUIi262o0P6S2AbCeb4v 5+75yqdvqLFEuSAm1CxdpNK/Rlagernv3HiEwuK3a9BhzsSgkax986AtgaDxDb/1kK8B gu8dnpwzDValht66yOrj47gKv7Lx01D+qsMAdz2zyeIOlvhXisY+gKigy2qcm2Qf8YO7 MWSgLY1AfpCi2OpAK/+tIZC5hBL99hgUSGYxFF5SkOHddVq05jHTCU2yUEPHh5cICtJm h6uxqYhGIxX/cYnU01EdnkkYrQV8rKqTF3/MftauRr9Ok25aO0JEvtLNTxg5G8Lm3uLh GoFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1710425898; x=1711030698; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=BZp9l6e5lWy9HD+MMXNWuQUDngomkZLkCLaBGKO4JoY=; b=NdGqZJZCsVCl00FrJPhDI6AmtcF5Dc9Pfpp5VyrRQutXStR+xKmC2cNQoYs2SJlzQd RbWvHGLN6AHt9o4iydn/TPo+MGWYXs1d7xkSeY1u0/i5bRb3NurlUHvefV9KJWBGmeP5 YO+W7VN4BsdaUi72H3wi2wr8HwYw6F6+e90dhD0+zZHKJ16Z0JDO4Nc5Zm38gYfzld9/ VzPbkfMqUvjgFb4r8WVjJPi7BbrPmHJMB5+PxwMCfzB0KPfyGrfyUW7rZKzzCcsXNfgJ aCN85Nkhia6YmVmWqR6PFKa2NIiaSzhZYAzzNDiiYU+/moerW/HSYsVbKQA5yAKCjkrN bwiA== X-Gm-Message-State: AOJu0YxN/s4REmFSthwXrp00JsOd8roGXoqJUm9MCjypWwCUC6VDQfsx w55ZfzTrwn2WtaNbH9zPrsolOW2kwrtOKHs7eGANz7pBxKKxJMOj6g84nbJ53NFUtCu8aBzFqAy nXP9STuyj5w== X-Google-Smtp-Source: AGHT+IEZARZbi9Qxxiolg+9KvQPeuIJ7hIz8XeqNI/1nxlVaVS3zFkwGXh/Ae/yu+2fjv5QIy6o56fUCC2ZAVg== X-Received: from edumazet1.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:395a]) (user=edumazet job=sendgmr) by 2002:a05:6902:1026:b0:dc7:5aad:8965 with SMTP id x6-20020a056902102600b00dc75aad8965mr539575ybt.0.1710425898449; Thu, 14 Mar 2024 07:18:18 -0700 (PDT) Date: Thu, 14 Mar 2024 14:18:16 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.44.0.278.ge034bb2e1d-goog Message-ID: <20240314141816.2640229-1-edumazet@google.com> Subject: [PATCH net] packet: annotate data-races around ignore_outgoing From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , syzbot+c669c1136495a2e7c31f@syzkaller.appspotmail.com, Willem de Bruijn X-Patchwork-Delegate: kuba@kernel.org ignore_outgoing is read locklessly from dev_queue_xmit_nit() and packet_getsockopt() Add appropriate READ_ONCE()/WRITE_ONCE() annotations. syzbot reported: BUG: KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt write to 0xffff888107804542 of 1 bytes by task 22618 on cpu 0: packet_setsockopt+0xd83/0xfd0 net/packet/af_packet.c:4003 do_sock_setsockopt net/socket.c:2311 [inline] __sys_setsockopt+0x1d8/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2340 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 read to 0xffff888107804542 of 1 bytes by task 27 on cpu 1: dev_queue_xmit_nit+0x82/0x620 net/core/dev.c:2248 xmit_one net/core/dev.c:3527 [inline] dev_hard_start_xmit+0xcc/0x3f0 net/core/dev.c:3547 __dev_queue_xmit+0xf24/0x1dd0 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] batadv_send_skb_packet+0x264/0x300 net/batman-adv/send.c:108 batadv_send_broadcast_skb+0x24/0x30 net/batman-adv/send.c:127 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x3f0/0x4b0 net/batman-adv/bat_iv_ogm.c:1700 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335 worker_thread+0x526/0x730 kernel/workqueue.c:3416 kthread+0x1d1/0x210 kernel/kthread.c:388 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 27 Comm: kworker/u8:1 Tainted: G W 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Fixes: fa788d986a3a ("packet: add sockopt to ignore outgoing packets") Reported-by: syzbot+c669c1136495a2e7c31f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/CANn89i+Z7MfbkBLOv=p7KZ7=K1rKHO4P1OL5LYDCtBiyqsa9oQ@mail.gmail.com/T/#t Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Reviewed-by: Willem de Bruijn Reviewed-by: Jason Xing --- net/core/dev.c | 2 +- net/packet/af_packet.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 0766a245816bdf70f6609dc7b6d694ae81e7a9e5..722787c3275527f1652ec98623f61500ee753b45 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2245,7 +2245,7 @@ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) rcu_read_lock(); again: list_for_each_entry_rcu(ptype, ptype_list, list) { - if (ptype->ignore_outgoing) + if (READ_ONCE(ptype->ignore_outgoing)) continue; /* Never send packets back to the socket diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 61270826b9ac73e66f9011c3230d4668f0bf7c77..7cfc7d301508fcead214fbdb4e962b0553a17916 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -4000,7 +4000,7 @@ packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, if (val < 0 || val > 1) return -EINVAL; - po->prot_hook.ignore_outgoing = !!val; + WRITE_ONCE(po->prot_hook.ignore_outgoing, !!val); return 0; } case PACKET_TX_HAS_OFF: @@ -4134,7 +4134,7 @@ static int packet_getsockopt(struct socket *sock, int level, int optname, 0); break; case PACKET_IGNORE_OUTGOING: - val = po->prot_hook.ignore_outgoing; + val = READ_ONCE(po->prot_hook.ignore_outgoing); break; case PACKET_ROLLOVER_STATS: if (!po->rollover)