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Wed, 03 Jul 2024 06:44:43 -0700 (PDT) Received: from kernelexploit-virtual-machine.localdomain ([121.185.186.233]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-72c6a8deff2sm6873399a12.37.2024.07.03.06.44.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Jul 2024 06:44:42 -0700 (PDT) From: Jeongjun Park To: syzbot+705c61d60b091ef42c04@syzkaller.appspotmail.com Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [net?] possible deadlock in team_del_slave (3) Date: Wed, 3 Jul 2024 22:44:39 +0900 Message-Id: <20240703134439.79904-1-aha310510@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <000000000000ffc5d80616fea23d@google.com> References: <000000000000ffc5d80616fea23d@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit #syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- drivers/net/team/team_core.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c index ab1935a4aa2c..3ac82df876b0 100644 --- a/drivers/net/team/team_core.c +++ b/drivers/net/team/team_core.c @@ -1970,11 +1970,12 @@ static int team_add_slave(struct net_device *dev, struct net_device *port_dev, struct netlink_ext_ack *extack) { struct team *team = netdev_priv(dev); - int err; + int err, locked; - mutex_lock(&team->lock); + locked = mutex_trylock(&team->lock); err = team_port_add(team, port_dev, extack); - mutex_unlock(&team->lock); + if (locked) + mutex_unlock(&team->lock); if (!err) netdev_change_features(dev); @@ -1985,11 +1986,12 @@ static int team_add_slave(struct net_device *dev, struct net_device *port_dev, static int team_del_slave(struct net_device *dev, struct net_device *port_dev) { struct team *team = netdev_priv(dev); - int err; + int err, locked; - mutex_lock(&team->lock); + locked = mutex_trylock(&team->lock); err = team_port_del(team, port_dev); - mutex_unlock(&team->lock); + if (locked) + mutex_unlock(&team->lock); if (err) return err; --