linux-kernel - Re: [syzbot] Re: [syzbot] [net?] possible deadlock in team_device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <000000000000b2f64b061e8a1701@google.com>
Date: Wed, 31 Jul 2024 05:18:32 -0700
From: syzbot <syzbot+b668da2bc4cb9670bf58@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org
Subject: Re: [syzbot] Re: [syzbot] [net?] possible deadlock in
 team_device_event (3)

For archival purposes, forwarding an incoming command email to
linux-kernel@...r.kernel.org.

***

Subject: Re: [syzbot] [net?] possible deadlock in team_device_event (3)
Author: aha310510@...il.com

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master 

---
 drivers/net/team/team_core.c | 5 ++++-
 include/linux/if_team.h      | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c
index ab1935a4aa2c..963c8311694f 100644
--- a/drivers/net/team/team_core.c
+++ b/drivers/net/team/team_core.c
@@ -1621,6 +1621,7 @@ static int team_init(struct net_device *dev)
 	team->dev = dev;
 	team_set_no_mode(team);
 	team->notifier_ctx = false;
+	team->nested_depth = 1;
 
 	team->pcpu_stats = netdev_alloc_pcpu_stats(struct team_pcpu_stats);
 	if (!team->pcpu_stats)
@@ -2947,8 +2948,10 @@ static void team_port_change_check(struct team_port *port, bool linkup)
 {
 	struct team *team = port->team;
 
-	mutex_lock(&team->lock);
+	mutex_lock_nested(&team->lock, team->nested_depth);
+	team->nested_depth++;
 	__team_port_change_check(port, linkup);
+	team->nested_depth--;
 	mutex_unlock(&team->lock);
 }
 
diff --git a/include/linux/if_team.h b/include/linux/if_team.h
index cdc684e04a2f..f8b4e3ed4b44 100644
--- a/include/linux/if_team.h
+++ b/include/linux/if_team.h
@@ -225,6 +225,7 @@ struct team {
 	} mcast_rejoin;
 	struct lock_class_key team_lock_key;
 	long mode_priv[TEAM_MODE_PRIV_LONGS];
+	unsigned int nested_depth;
 };
 
 static inline int team_dev_queue_xmit(struct team *team, struct team_port *port,
--