syzbot


possible deadlock in dev_uc_sync

Status: auto-closed as invalid on 2020/12/02 10:24
Reported-by: syzbot+6579928b65a528cd8b78@syzkaller.appspotmail.com
First crash: 1592d, last: 1592d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in dev_uc_sync net C done 3 1523d 1620d 15/28 fixed on 2020/11/16 12:12
linux-4.14 possible deadlock in dev_uc_sync 1 1574d 1574d 0/1 auto-closed as invalid on 2020/12/19 23:00

Sample crash report:
device team_slave_0 entered promiscuous mode
device team_slave_1 entered promiscuous mode
======================================================
WARNING: possible circular locking dependency detected
4.19.136-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.3/31530 is trying to acquire lock:
00000000736e05db (&dev_addr_list_lock_key#2/1){+...}, at: netif_addr_lock_nested include/linux/netdevice.h:3991 [inline]
00000000736e05db (&dev_addr_list_lock_key#2/1){+...}, at: dev_uc_sync+0x11a/0x1e0 net/core/dev_addr_lists.c:544

but task is already holding lock:
00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline]
00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: netif_addr_lock_bh include/linux/netdevice.h:3996 [inline]
00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: dev_set_rx_mode net/core/dev.c:7597 [inline]
00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: __dev_open+0x264/0x3a0 net/core/dev.c:1410

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&macvlan_netdev_addr_lock_key#2/2){+...}:
       netif_addr_lock_nested include/linux/netdevice.h:3991 [inline]
       dev_uc_sync_multiple+0x11a/0x1e0 net/core/dev_addr_lists.c:574
       team_set_rx_mode+0xce/0x230 drivers/net/team/team.c:1788
       __dev_set_rx_mode+0x1d9/0x2f0 net/core/dev.c:7592
       dev_uc_sync+0x193/0x1e0 net/core/dev_addr_lists.c:547
       macvlan_set_mac_lists+0x55/0x110 drivers/net/macvlan.c:806
       __dev_set_rx_mode+0x1d9/0x2f0 net/core/dev.c:7592
       dev_set_rx_mode net/core/dev.c:7598 [inline]
       __dev_open+0x26c/0x3a0 net/core/dev.c:1410
       __dev_change_flags+0x501/0x660 net/core/dev.c:7670
       rtnl_configure_link+0xec/0x230 net/core/rtnetlink.c:2830
       rtnl_newlink+0x104e/0x15b0 net/core/rtnetlink.c:3161
       rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
       netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
       sock_sendmsg_nosec net/socket.c:622 [inline]
       sock_sendmsg+0xc3/0x120 net/socket.c:632
       ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
       __sys_sendmsg net/socket.c:2153 [inline]
       __do_sys_sendmsg net/socket.c:2162 [inline]
       __se_sys_sendmsg net/socket.c:2160 [inline]
       __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #0 (&dev_addr_list_lock_key#2/1){+...}:
       _raw_spin_lock_nested+0x30/0x40 kernel/locking/spinlock.c:354
       netif_addr_lock_nested include/linux/netdevice.h:3991 [inline]
       dev_uc_sync+0x11a/0x1e0 net/core/dev_addr_lists.c:544
       macvlan_set_mac_lists+0x55/0x110 drivers/net/macvlan.c:806
       __dev_set_rx_mode+0x1d9/0x2f0 net/core/dev.c:7592
       dev_set_rx_mode net/core/dev.c:7598 [inline]
       __dev_open+0x26c/0x3a0 net/core/dev.c:1410
       __dev_change_flags+0x501/0x660 net/core/dev.c:7670
       rtnl_configure_link+0xec/0x230 net/core/rtnetlink.c:2830
       rtnl_newlink+0x104e/0x15b0 net/core/rtnetlink.c:3161
       rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
       netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
       sock_sendmsg_nosec net/socket.c:622 [inline]
       sock_sendmsg+0xc3/0x120 net/socket.c:632
       ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
       __sys_sendmsg net/socket.c:2153 [inline]
       __do_sys_sendmsg net/socket.c:2162 [inline]
       __se_sys_sendmsg net/socket.c:2160 [inline]
       __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&macvlan_netdev_addr_lock_key#2/2);
                               lock(&dev_addr_list_lock_key#2/1);
                               lock(&macvlan_netdev_addr_lock_key#2/2);
  lock(&dev_addr_list_lock_key#2/1);

 *** DEADLOCK ***

2 locks held by syz-executor.3/31530:
 #0: 0000000067b9e03a (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 0000000067b9e03a (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4775
 #1: 00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline]
 #1: 00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: netif_addr_lock_bh include/linux/netdevice.h:3996 [inline]
 #1: 00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: dev_set_rx_mode net/core/dev.c:7597 [inline]
 #1: 00000000235295eb (&macvlan_netdev_addr_lock_key#2/2){+...}, at: __dev_open+0x264/0x3a0 net/core/dev.c:1410

stack backtrace:
CPU: 0 PID: 31530 Comm: syz-executor.3 Not tainted 4.19.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221
 check_prev_add kernel/locking/lockdep.c:1865 [inline]
 check_prevs_add kernel/locking/lockdep.c:1978 [inline]
 validate_chain kernel/locking/lockdep.c:2419 [inline]
 __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415
 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907
 _raw_spin_lock_nested+0x30/0x40 kernel/locking/spinlock.c:354
 netif_addr_lock_nested include/linux/netdevice.h:3991 [inline]
 dev_uc_sync+0x11a/0x1e0 net/core/dev_addr_lists.c:544
 macvlan_set_mac_lists+0x55/0x110 drivers/net/macvlan.c:806
 __dev_set_rx_mode+0x1d9/0x2f0 net/core/dev.c:7592
 dev_set_rx_mode net/core/dev.c:7598 [inline]
 __dev_open+0x26c/0x3a0 net/core/dev.c:1410
 __dev_change_flags+0x501/0x660 net/core/dev.c:7670
 rtnl_configure_link+0xec/0x230 net/core/rtnetlink.c:2830
 rtnl_newlink+0x104e/0x15b0 net/core/rtnetlink.c:3161
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cce9
Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2560fdec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002c080 RCX: 000000000045cce9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffce7b4fa0f R14: 00007f2560fdf9c0 R15: 000000000078bf0c
device macvtap0 entered promiscuous mode
device team0 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap0
device macvtap1 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap1
netlink: 40 bytes leftover after parsing attributes in process `syz-executor.5'.
Invalid UDP bearer configuration
Enabling of bearer <udp:syz1> rejected, failed to enable media
device macvtap1 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap1
device macvtap2 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap2
device macvtap2 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap2
device macvtap3 entered promiscuous mode
8021q: adding VLAN 0 to HW filter on device macvtap3
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
nla_parse: 5 callbacks suppressed
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/04 10:24 linux-4.19.y 13af6c74b14a 80a06902 .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.