====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc8-syzkaller-00021-ge1c04510f521 #0 Not tainted ------------------------------------------------------ syz-executor.2/12318 is trying to acquire lock: ffff88801caa3130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1725 [inline] ffff88801caa3130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppoe_flush_dev drivers/net/ppp/pppoe.c:304 [inline] ffff88801caa3130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppoe_device_event+0x329/0x980 drivers/net/ppp/pppoe.c:346 but task is already holding lock: ffffffff8e0c92d0 (dev_addr_sem){++++}-{3:3}, at: dev_set_mac_address_user+0x23/0x50 net/core/dev.c:8804 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (dev_addr_sem){++++}-{3:3}: down_write+0x94/0x220 kernel/locking/rwsem.c:1562 dev_set_mac_address_user+0x23/0x50 net/core/dev.c:8804 do_setlink+0x18c4/0x3bb0 net/core/rtnetlink.c:2775 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 __sys_sendto+0x23a/0x340 net/socket.c:2117 __do_compat_sys_socketcall+0x62e/0x720 net/compat.c:474 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #2 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1360 kernel/locking/mutex.c:747 prb_calc_retire_blk_tmo+0x7d/0x1e0 net/packet/af_packet.c:576 init_prb_bdqc net/packet/af_packet.c:634 [inline] packet_set_ring+0x158f/0x1980 net/packet/af_packet.c:4439 packet_setsockopt+0x1a32/0x3a30 net/packet/af_packet.c:3808 __sys_setsockopt+0x2c6/0x5b0 net/socket.c:2246 __do_sys_setsockopt net/socket.c:2257 [inline] __se_sys_setsockopt net/socket.c:2254 [inline] __ia32_sys_setsockopt+0xbd/0x150 net/socket.c:2254 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #1 (sk_lock-AF_PACKET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3471 lock_sock include/net/sock.h:1725 [inline] l2tp_tunnel_register+0x2aa/0x11e0 net/l2tp/l2tp_core.c:1483 pppol2tp_connect+0xcdc/0x1a10 net/l2tp/l2tp_ppp.c:723 __sys_connect_file+0x153/0x1a0 net/socket.c:1976 __sys_connect+0x165/0x1a0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __ia32_sys_connect+0x72/0xb0 net/socket.c:2000 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #0 (sk_lock-AF_PPPOX){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3471 lock_sock include/net/sock.h:1725 [inline] pppoe_flush_dev drivers/net/ppp/pppoe.c:304 [inline] pppoe_device_event+0x329/0x980 drivers/net/ppp/pppoe.c:346 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] dev_set_mac_address+0x2d7/0x3e0 net/core/dev.c:8791 bond_set_mac_address+0x359/0x7a0 drivers/net/bonding/bond_main.c:4743 dev_set_mac_address+0x26b/0x3e0 net/core/dev.c:8787 dev_set_mac_address_user+0x31/0x50 net/core/dev.c:8805 do_setlink+0x18c4/0x3bb0 net/core/rtnetlink.c:2775 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 other info that might help us debug this: Chain exists of: sk_lock-AF_PPPOX --> rtnl_mutex --> dev_addr_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(dev_addr_sem); lock(rtnl_mutex); lock(dev_addr_sem); lock(sk_lock-AF_PPPOX); *** DEADLOCK *** 2 locks held by syz-executor.2/12318: #0: ffffffff8e0d60a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:75 [inline] #0: ffffffff8e0d60a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3e9/0xca0 net/core/rtnetlink.c:6138 #1: ffffffff8e0c92d0 (dev_addr_sem){++++}-{3:3}, at: dev_set_mac_address_user+0x23/0x50 net/core/dev.c:8804 stack backtrace: CPU: 1 PID: 12318 Comm: syz-executor.2 Not tainted 6.2.0-rc8-syzkaller-00021-ge1c04510f521 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3471 lock_sock include/net/sock.h:1725 [inline] pppoe_flush_dev drivers/net/ppp/pppoe.c:304 [inline] pppoe_device_event+0x329/0x980 drivers/net/ppp/pppoe.c:346 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] dev_set_mac_address+0x2d7/0x3e0 net/core/dev.c:8791 bond_set_mac_address+0x359/0x7a0 drivers/net/bonding/bond_main.c:4743 dev_set_mac_address+0x26b/0x3e0 net/core/dev.c:8787 dev_set_mac_address_user+0x31/0x50 net/core/dev.c:8805 do_setlink+0x18c4/0x3bb0 net/core/rtnetlink.c:2775 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f5b549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f565cc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 device bond0 entered promiscuous mode device bond_slave_0 entered promiscuous mode device bond_slave_1 entered promiscuous mode ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi