[PATCH 6.12 310/567] team: fix check for port enabled in team_queue_override_port_prio_changed()

Greg Kroah-Hartman
2026-01-06T17:31:26Z

From: Jiri Pirko <jiri@nvidia.com>

[ Upstream commit 932ac51d9953eaf77a1252f79b656d4ca86163c6 ]

There has been a syzkaller bug reported recently with the following
trace:

list_del corruption, ffff888058bea080->prev is LIST_POISON2 (dead000000000122)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:59!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 3 UID: 0 PID: 21246 Comm: syz.0.2928 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__list_del_entry_valid_or_report+0x13e/0x200 lib/list_debug.c:59
Code: 48 c7 c7 e0 71 f0 8b e8 30 08 ef fc 90 0f 0b 48 89 ef e8 a5 02 55 fd 48 89 ea 48 89 de 48 c7 c7 40 72 f0 8b e8 13 08 ef fc 90 <0f> 0b 48 89 ef e8 88 02 55 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000d49f370 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffff888058bea080 RCX: ffffc9002817d000
RDX: 0000000000000000 RSI: ffffffff819becc6 RDI: 0000000000000005
RBP: dead000000000122 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff888039e9c230
R13: ffff888058bea088 R14: ffff888058bea080 R15: ffff888055461480
FS: 00007fbbcfe6f6c0(0000) GS:ffff8880d6d0a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3afcb0 CR3: 00000000382c7000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__list_del_entry_valid include/linux/list.h:132 [inline]
__list_del_entry include/linux/list.h:223 [inline]
list_del_rcu include/linux/rculist.h:178 [inline]
__team_queue_override_port_del drivers/net/team/team_core.c:826 [inline]
__team_queue_override_port_del drivers/net/team/team_core.c:821 [inline]
team_queue_override_port_prio_changed drivers/net/team/team_core.c:883 [inline]
team_priority_option_set+0x171/0x2f0 drivers/net/team/team_core.c:1534
team_option_set drivers/net/team/team_core.c:376 [inline]
team_nl_options_set_doit+0x8ae/0xe60 drivers/net/team/team_core.c:2653
genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The problem is in this flow:
1) Port is enabled, queue_id != 0, in qom_list
2) Port gets disabled
-> team_port_disable()
-> team_queue_override_port_del()
-> del (removed from list)
3) Port is disabled, queue_id != 0, not in any list
4) Priority changes
-> team_queue_override_port_prio_changed()
-> checks: port disabled && queue_id != 0
-> calls del - hits the BUG as it is removed already

To fix this, change the check in team_queue_override_port_prio_changed()
so it returns early if port is not enabled.

Reported-by: syzbot+422806e5f4cce722a71f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=422806e5f4cce722a71f
Fixes: 6c31ff366c11 ("team: remove synchronize_rcu() called during queue override change")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251212102953.167287-1-jiri@resnulli.us
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/team/team_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c
index 94c40c5cebdd..50732f9699ee 100644
--- a/drivers/net/team/team_core.c
+++ b/drivers/net/team/team_core.c
@@ -877,7 +877,7 @@ static void __team_queue_override_enabled_check(struct team *team)
static void team_queue_override_port_prio_changed(struct team *team,
struct team_port *port)
{
- if (!port->queue_id || team_port_enabled(port))
+ if (!port->queue_id || !team_port_enabled(port))
return;
__team_queue_override_port_del(team, port);
__team_queue_override_port_add(team, port);
--
2.51.0