[moderation] [net?] KCSAN: data-race in ipvlan_open / is_upper_ndev_bond_master_filter (10)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8a30aeb0d1b4 Merge tag 'nfsd-7.0-2' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1686f352580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3a78dd265deac3a9
dashboard link: https://syzkaller.appspot.com/bug?extid=570a19301854446f586f
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
CC: [da...@davemloft.net edum...@google.com ho...@kernel.org ku...@kernel.org linux-...@vger.kernel.org net...@vger.kernel.org pab...@redhat.com]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d210c1d5bea9/disk-8a30aeb0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0f40c70c1c61/vmlinux-8a30aeb0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0a2ee2732326/bzImage-8a30aeb0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+570a19...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in ipvlan_open / is_upper_ndev_bond_master_filter

read-write to 0xffff88811be7b0b0 of 4 bytes by task 13371 on cpu 1:
ipvlan_open+0x74/0x100 drivers/net/ipvlan/ipvlan_main.c:-1
__dev_open+0x321/0x560 net/core/dev.c:1702
__dev_change_flags+0x13e/0x400 net/core/dev.c:9764
rtnl_configure_link net/core/rtnetlink.c:3594 [inline]
rtnl_newlink_create+0x392/0x650 net/core/rtnetlink.c:3850
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x10a0/0x1330 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2550
rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6985
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5c0/0x690 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0x563/0x5b0 net/socket.c:2592
___sys_sendmsg+0x195/0x1e0 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0xd4/0x160 net/socket.c:2681
x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811be7b0b0 of 4 bytes by task 6907 on cpu 0:
netif_is_bond_master include/linux/netdevice.h:5484 [inline]
is_upper_ndev_bond_master_filter+0x2b/0xb0 drivers/infiniband/core/roce_gid_mgmt.c:275
ib_enum_roce_netdev+0x122/0x1d0 drivers/infiniband/core/device.c:2390
ib_enum_all_roce_netdevs+0x89/0x100 drivers/infiniband/core/device.c:2417
netdevice_event_work_handler+0x67/0x3d0 drivers/infiniband/core/roce_gid_mgmt.c:648
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0x513/0xa10 kernel/workqueue.c:3359
worker_thread+0x58a/0x780 kernel/workqueue.c:3440
kthread+0x22a/0x280 kernel/kthread.c:436
ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00008002 -> 0x00008083

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6907 Comm: kworker/u8:21 Tainted: G W syzkaller #0 PREEMPT(full)
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: gid-cache-wq netdevice_event_work_handler
==================================================================


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