[syzbot] BUG: stack guard page was hit in rtnl_newlink

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7fef2edf7cc7 sd: don't mess with SD_MINORS for CONFIG_DEBU..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=118eebc2300000
kernel config: https://syzkaller.appspot.com/x/.config?x=bcfdb4db27992419
dashboard link: https://syzkaller.appspot.com/bug?extid=399cbcbb7917bd2f96ee
compiler: Debian clang version 11.0.1-2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+399cbc...@syzkaller.appspotmail.com

BUG: stack guard page was hit at ffffc900024fff18 (stack is ffffc90002500000..ffffc90002507fff)
kernel stack overflow (double-fault): 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 14026 Comm: syz-executor.5 Tainted: G W 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:lock_acquire+0x3c/0x4a0 kernel/locking/lockdep.c:5593
Code: 81 ec 20 01 00 00 45 89 c6 41 89 f7 48 89 fb 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 49 bc 00 00 00 00 00 fc ff df <48> c7 44 24 40 b3 8a b5 41 48 c7 44 24 48 bc d5 f8 8b 48 c7 44 24
RSP: 0018:ffffc900024fff20 EFLAGS: 00010282
RAX: a66bc51f58bac500 RBX: ffffffff8c717740 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c717740
RBP: ffffc90002500070 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1010ef9415 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff920004a001c R14: 0000000000000000 R15: 0000000000000000
FS: 00007f699499a700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900024fff18 CR3: 0000000038cf6000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:267
rcu_read_lock include/linux/rcupdate.h:687 [inline]
dev_get_alias+0x25/0x1d0 net/core/dev.c:1477
nla_put_ifalias+0x91/0x120 net/core/rtnetlink.c:1571
rtnl_fill_ifinfo+0x108b/0x4a10 net/core/rtnetlink.c:1749
rtmsg_ifinfo_build_skb+0xe2/0x180 net/core/rtnetlink.c:3815
rtmsg_ifinfo_event net/core/rtnetlink.c:3847 [inline]
rtnetlink_event+0xed/0x1b0 net/core/rtnetlink.c:5625
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_change_features+0x72/0x1b0 net/core/dev.c:10060
team_compute_features drivers/net/team/team.c:1026 [inline]
team_device_event+0x299/0x470 drivers/net/team/team.c:3007
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
call_netdevice_notifiers_info net/core/dev.c:2122 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2134 [inline]
call_netdevice_notifiers net/core/dev.c:2148 [inline]
netdev_features_change net/core/dev.c:1494 [inline]
netdev_sync_lower_features+0x3a3/0x600 net/core/dev.c:9841
__netdev_update_features+0x4c6/0x1260 net/core/dev.c:9988
netdev_update_features+0x6d/0x1c0 net/core/dev.c:10043
dev_disable_lro+0x43/0x280 net/core/dev.c:1766
br_add_if+0xcab/0x1a50 net/bridge/br_if.c:650
do_set_master net/core/rtnetlink.c:2524 [inline]
do_setlink+0xe51/0x3f70 net/core/rtnetlink.c:2728
__rtnl_newlink net/core/rtnetlink.c:3393 [inline]
rtnl_newlink+0x16e4/0x1cd0 net/core/rtnetlink.c:3508
rtnetlink_rcv_msg+0x91c/0xe50 net/core/rtnetlink.c:5574
netlink_rcv_skb+0x1f0/0x460 net/netlink/af_netlink.c:2504
netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
netlink_unicast+0x7de/0x9b0 net/netlink/af_netlink.c:1340
netlink_sendmsg+0x9e7/0xe00 net/netlink/af_netlink.c:1929
sock_sendmsg_nosec net/socket.c:702 [inline]
sock_sendmsg net/socket.c:722 [inline]
____sys_sendmsg+0x5a2/0x900 net/socket.c:2385
___sys_sendmsg net/socket.c:2439 [inline]
__sys_sendmsg+0x319/0x400 net/socket.c:2468
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f699499a188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 00007fffc1aaee5f R14: 00007f699499a300 R15: 0000000000022000
Modules linked in:
---[ end trace ac70e69260416dfc ]---
RIP: 0010:lock_acquire+0x3c/0x4a0 kernel/locking/lockdep.c:5593
Code: 81 ec 20 01 00 00 45 89 c6 41 89 f7 48 89 fb 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 49 bc 00 00 00 00 00 fc ff df <48> c7 44 24 40 b3 8a b5 41 48 c7 44 24 48 bc d5 f8 8b 48 c7 44 24
RSP: 0018:ffffc900024fff20 EFLAGS: 00010282
RAX: a66bc51f58bac500 RBX: ffffffff8c717740 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c717740
RBP: ffffc90002500070 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1010ef9415 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff920004a001c R14: 0000000000000000 R15: 0000000000000000
FS: 00007f699499a700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900024fff18 CR3: 0000000038cf6000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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[Hillf Danton]

On Sat, 17 Jul 2021 06:42:23 -0700

Add counter to track __netdev_update_features recursion depth and do no
more updates if recursion detected to cut the risk of stack overflow.

Now only for thoughts.

+++ x/net/core/dev.c
@@ -9954,6 +9954,8 @@ static netdev_features_t netdev_fix_feat
return features;
}

+static struct percpu_counter update_features_count;
+
int __netdev_update_features(struct net_device *dev)
{
struct net_device *upper, *lower;
@@ -9963,6 +9965,11 @@ int __netdev_update_features(struct net_

ASSERT_RTNL();

+ /* no more updates to avoid stack overflow */
+ if (percpu_counter_sum(&update_features_count))
+ return 0;
+ percpu_counter_inc(&update_features_count);
+
features = netdev_get_wanted_features(dev);

if (dev->netdev_ops->ndo_fix_features)
@@ -9987,6 +9994,7 @@ int __netdev_update_features(struct net_
err = 0;

if (unlikely(err < 0)) {
+ percpu_counter_dec(&update_features_count);
netdev_err(dev,
"set_features() failed (%d); wanted %pNF, left %pNF\n",
err, &features, &dev->features);
@@ -10042,6 +10050,7 @@ sync_lower:

dev->features = features;
}
+ percpu_counter_dec(&update_features_count);

return err < 0 ? 0 : 1;
}

[Hillf Danton]

On Sat, 17 Jul 2021 06:42:23 -0700

Add counter to track __netdev_update_features recursion depth and do no
more updates if recursion detected to cut the risk of stack overflow.

Now only for thoughts.

+++ x/net/core/dev.c

@@ -9956,6 +9956,7 @@ static netdev_features_t netdev_fix_feat

int __netdev_update_features(struct net_device *dev)
{
+ static int update_features_count;
struct net_device *upper, *lower;
netdev_features_t features;
struct list_head *iter;
@@ -9963,6 +9964,11 @@ int __netdev_update_features(struct net_

ASSERT_RTNL();

+ /* no more updates to avoid stack overflow */

+ if (update_features_count)
+ return 0;
+ update_features_count++;

+
features = netdev_get_wanted_features(dev);

if (dev->netdev_ops->ndo_fix_features)

@@ -9993,6 +9999,7 @@ int __netdev_update_features(struct net_
/* return non-0 since some features might have changed and
* it's better to fire a spurious notification than miss it
*/
+ update_features_count--;
return -1;
}

@@ -10042,6 +10049,7 @@ sync_lower:

dev->features = features;
}
+ update_features_count--;

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.