From patchwork Wed Mar 12 19:05:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislav Fomichev X-Patchwork-Id: 14013774 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (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 6B1E8250BFC; Wed, 12 Mar 2025 19:05:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741806321; cv=none; b=RkgtV+MLUVMlxgPV1NUAzaBgwDq0TCsqU+KFhmVwXnvzf+FFFGX/AkqhUOedVBngJz+MEcS9EXJXwEUUlI9bqBW0PDJ2NTPU6E80j3ulMI4CdA46AkGc8JguRx6Bh7fPWbr4MKthYS/B+apfTX4ggxZAsjbhfPsjbTna5KtXsQ8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741806321; c=relaxed/simple; bh=lj+QA6MCWR/k/sZj/3DnzloZd5ClpU3EuhrRVY7eYK0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FCdenFPaiNW5ijyie2Kb3/Wc1b5oe3JDel2LzWYMIO5vyyrS4itnGKc7GZWhjjrIvLrDrPkQKlCuut/9RkylHT+TLFGwsAOdT6gdvvutpuDo9DcjHoNv/VE1Su3OnxwaHznV4/gRypIxtxePKUDxmTav5nVTmyjVS639OJsP2DM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=fomichev.me; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=fomichev.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-219f8263ae0so4362625ad.0; Wed, 12 Mar 2025 12:05:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741806317; x=1742411117; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=jN5XMu0A2kj53iwwAVVDL87iRJmus00zHqg0uekmHLM=; b=hLs+wDZ8nZgyUdQF6aRFzG+1jVaK3uxThwsskFQCQvOY75F27Uh22Qe8TDTlt0zoyU PgNebBl/n9UxqB+VmeqgOr81shdusxROxsKYnK76CILjnkzc341KOIu0VkUw4bfkSy+g mhPRj2MBXGKXrgzGZFer3pnZHo1UQ3c5g8mgpht9pgKLXQA64TXvEv3VtQ+isfV6uEJr lmqzr59pDBU2X2x+i414iZk5hLT7nZM/ImGg4gFKRw53RntabeqvfHHNBfd/BtmCprsd pxR3DEUsrW7/sTZhXi9icOYpmsBv6lrfyMXu3N79QdZ4IS2lWu+0goD2ULPvrLKczFHF bOQw== X-Forwarded-Encrypted: i=1; AJvYcCUVXehDvt7vHcOLHqw2gtpTYfkVdizVFQ7I5Qn9oRZBnvN82LpHrgaJYtNHcvIHuJz2OLUHd5XUqb/2wpg=@vger.kernel.org X-Gm-Message-State: AOJu0Yx3K2g3MIxVQ+gph2LFjkJ1cI3gXRCcE9d/MAl3s7pGr/PZhGZV O7EzUWpk2DRXRKvjJ3m8VS8OwsZFBAyhuN7rIpPTrNtkQH19wKTBl+zPN5kz2g== X-Gm-Gg: ASbGncuNbXnfLZ/aLTiCeVzf1n/FVldARz03eoq7K/RRy86W8x1AGggfkb8sAlnvOgB AvS4Js9K4nCc9D1K5mXbzI4STfTOH7VHDxjkuWv3v7j+99YSHhejjnwUOenNiOX3JEfmy02hkM0 P92ZBSFTPlXFHPPgTG4ZUzECY/uDtSX/w7LAFGV138bZK9YB/b4dSU0tugSBMH4uVC+ypDgKMVW OWg6Fpv4UbqJPuItu5WQgejKUwGLJtOFxP9GU2xxAe2urZKzADMINhmblcsbPtKwYjdo7xVbxr1 7y1cINYpxhuOJ9bBM8oVgZy5wM8h1gb44sSlSH2I3Ecb X-Google-Smtp-Source: AGHT+IFFGcFhKa620lXkXfgQSkQyqnIb+cM+U0WnzVE2vALZVoOpw1kNCt1eCKZ6cnYVg4R0n7nFpw== X-Received: by 2002:a17:903:46c8:b0:224:1220:7f40 with SMTP id d9443c01a7336-22592e20112mr113536415ad.3.1741806317422; Wed, 12 Mar 2025 12:05:17 -0700 (PDT) Received: from localhost ([2601:646:9e00:f56e:2844:3d8f:bf3e:12cc]) by smtp.gmail.com with UTF8SMTPSA id 98e67ed59e1d1-3010345ad34sm2175560a91.1.2025.03.12.12.05.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Mar 2025 12:05:17 -0700 (PDT) From: Stanislav Fomichev To: netdev@vger.kernel.org Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org, willemdebruijn.kernel@gmail.com, jasowang@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, sdf@fomichev.me, jdamato@fastly.com, kory.maincent@bootlin.com, kuniyu@amazon.com, atenart@kernel.org, Kohei Enju Subject: [PATCH net-next v2 2/2] net: reorder dev_addr_sem lock Date: Wed, 12 Mar 2025 12:05:13 -0700 Message-ID: <20250312190513.1252045-3-sdf@fomichev.me> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250312190513.1252045-1-sdf@fomichev.me> References: <20250312190513.1252045-1-sdf@fomichev.me> 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 Lockdep complains about circular lock in 1 -> 2 -> 3 (see below). Change the lock ordering to be: - rtnl_lock - dev_addr_sem - netdev_ops (only for lower devices!) - team_lock (or other per-upper device lock) 1. rtnl_lock -> netdev_ops -> dev_addr_sem rtnl_setlink rtnl_lock do_setlink IFLA_ADDRESS on lower netdev_ops dev_addr_sem 2. rtnl_lock -> team_lock -> netdev_ops rtnl_newlink rtnl_lock do_setlink IFLA_MASTER on lower do_set_master team_add_slave team_lock team_port_add dev_set_mtu netdev_ops 3. rtnl_lock -> dev_addr_sem -> team_lock rtnl_newlink rtnl_lock do_setlink IFLA_ADDRESS on upper dev_addr_sem netif_set_mac_address team_set_mac_address team_lock 4. rtnl_lock -> netdev_ops -> dev_addr_sem rtnl_lock dev_ifsioc dev_set_mac_address_user __tun_chr_ioctl rtnl_lock dev_set_mac_address_user tap_ioctl rtnl_lock dev_set_mac_address_user dev_set_mac_address_user netdev_lock_ops netif_set_mac_address_user dev_addr_sem v2: - move lock reorder to happen after kmalloc (Kuniyuki) Cc: Kohei Enju Fixes: df43d8bf1031 ("net: replace dev_addr_sem with netdev instance lock") Signed-off-by: Stanislav Fomichev Reviewed-by: Kuniyuki Iwashima --- include/linux/netdevice.h | 2 -- net/core/dev.c | 11 ----------- net/core/dev_api.c | 4 +++- net/core/rtnetlink.c | 15 +++++++++++++-- 4 files changed, 16 insertions(+), 16 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 42c75cb028e7..2bf1f914f61a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4198,8 +4198,6 @@ int netif_set_mac_address(struct net_device *dev, struct sockaddr *sa, struct netlink_ext_ack *extack); int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, struct netlink_ext_ack *extack); -int netif_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, - struct netlink_ext_ack *extack); int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, struct netlink_ext_ack *extack); int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name); diff --git a/net/core/dev.c b/net/core/dev.c index 5a64389461e2..66290c159ad8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -9592,17 +9592,6 @@ int netif_set_mac_address(struct net_device *dev, struct sockaddr *sa, DECLARE_RWSEM(dev_addr_sem); -int netif_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, - struct netlink_ext_ack *extack) -{ - int ret; - - down_write(&dev_addr_sem); - ret = netif_set_mac_address(dev, sa, extack); - up_write(&dev_addr_sem); - return ret; -} - int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) { size_t size = sizeof(sa->sa_data_min); diff --git a/net/core/dev_api.c b/net/core/dev_api.c index 2e17548af685..8dbc60612100 100644 --- a/net/core/dev_api.c +++ b/net/core/dev_api.c @@ -89,9 +89,11 @@ int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, { int ret; + down_write(&dev_addr_sem); netdev_lock_ops(dev); - ret = netif_set_mac_address_user(dev, sa, extack); + ret = netif_set_mac_address(dev, sa, extack); netdev_unlock_ops(dev); + up_write(&dev_addr_sem); return ret; } diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 9355058bf996..5a24a30dfc2d 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3088,13 +3088,24 @@ static int do_setlink(const struct sk_buff *skb, struct net_device *dev, goto errout; } sa->sa_family = dev->type; + + netdev_unlock_ops(dev); + + /* dev_addr_sem is an outer lock, enforce proper ordering */ + down_write(&dev_addr_sem); + netdev_lock_ops(dev); + memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]), dev->addr_len); - err = netif_set_mac_address_user(dev, sa, extack); + err = netif_set_mac_address(dev, sa, extack); kfree(sa); - if (err) + if (err) { + up_write(&dev_addr_sem); goto errout; + } status |= DO_SETLINK_MODIFIED; + + up_write(&dev_addr_sem); } if (tb[IFLA_MTU]) {