================================ WARNING: inconsistent lock state 6.11.0-syzkaller-11624-ge477dba5442c #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.1.1061/9283 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88802934b1e0 (&pch->downl){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88802934b1e0 (&pch->downl){+.?.}-{2:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ffff88802934b1e0 (&pch->downl){+.?.}-{2:2}, at: ppp_input+0x104/0xbb0 drivers/net/ppp/ppp_generic.c:2304 {SOFTIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5822 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x104/0xbb0 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x22c/0x320 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x35f/0x400 net/core/sock.c:3072 release_sock+0x5a/0x220 net/core/sock.c:3626 pppoe_sendmsg+0x5e6/0x770 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg net/socket.c:744 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2602 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2656 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2742 __do_sys_sendmmsg net/socket.c:2771 [inline] __se_sys_sendmmsg net/socket.c:2768 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2768 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 2526 hardirqs last enabled at (2526): [] __local_bh_enable_ip+0xa4/0x120 kernel/softirq.c:387 hardirqs last disabled at (2525): [] __local_bh_enable_ip+0xcd/0x120 kernel/softirq.c:364 softirqs last enabled at (2494): [] pppoe_sendmsg+0x5e6/0x770 drivers/net/ppp/pppoe.c:903 softirqs last disabled at (2499): [] __do_softirq kernel/softirq.c:588 [inline] softirqs last disabled at (2499): [] invoke_softirq kernel/softirq.c:428 [inline] softirqs last disabled at (2499): [] __irq_exit_rcu kernel/softirq.c:637 [inline] softirqs last disabled at (2499): [] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&pch->downl); lock(&pch->downl); *** DEADLOCK *** 6 locks held by syz.1.1061/9283: #0: ffff888028968198 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff888028968198 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6099 [inline] #0: ffff888028968198 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x35/0x6a0 mm/memory.c:6159 #1: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: count_memcg_events_mm.constprop.0+0x3a/0x340 include/linux/memcontrol.h:1042 #2: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: local_lock_release include/linux/local_lock_internal.h:38 [inline] #2: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x3f1/0x15f0 net/core/dev.c:6105 #3: ffff8880245f31d8 (slock-AF_PPPOX){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #3: ffff8880245f31d8 (slock-AF_PPPOX){+.-.}-{2:2}, at: __sk_receive_skb+0x1dd/0x890 net/core/sock.c:563 #4: ffff8880245f3258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: sk_receive_skb include/net/sock.h:1898 [inline] #4: ffff8880245f3258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppoe_rcv+0x7b2/0xa70 drivers/net/ppp/pppoe.c:451 #5: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #5: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #5: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2267 [inline] #5: ffffffff8e1b7f80 (rcu_read_lock){....}-{1:2}, at: ppp_input+0x70/0xbb0 drivers/net/ppp/ppp_generic.c:2304 stack backtrace: CPU: 2 UID: 0 PID: 9283 Comm: syz.1.1061 Not tainted 6.11.0-syzkaller-11624-ge477dba5442c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_usage_bug.part.0+0x3a2/0x560 kernel/locking/lockdep.c:4035 print_usage_bug kernel/locking/lockdep.c:4003 [inline] valid_state kernel/locking/lockdep.c:4049 [inline] mark_lock_irq kernel/locking/lockdep.c:4260 [inline] mark_lock+0x92d/0xc60 kernel/locking/lockdep.c:4722 mark_usage kernel/locking/lockdep.c:4611 [inline] __lock_acquire+0x11e1/0x3ce0 kernel/locking/lockdep.c:5153 lock_acquire kernel/locking/lockdep.c:5822 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x104/0xbb0 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x22c/0x320 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __sk_receive_skb+0x7aa/0x890 net/core/sock.c:570 sk_receive_skb include/net/sock.h:1898 [inline] pppoe_rcv+0x7b2/0xa70 drivers/net/ppp/pppoe.c:451 __netif_receive_skb_one_core+0x1b1/0x1e0 net/core/dev.c:5662 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5775 process_backlog+0x443/0x15f0 net/core/dev.c:6107 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0xa92/0x1010 net/core/dev.c:6962 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5790 Code: c1 05 da 80 98 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc9000d91f738 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92001b23ee9 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8b6ccf40 RDI: ffffffff8bd196e0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dc2b88 R10: ffffffff96e15c47 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8e1b7f80 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] count_memcg_events_mm.constprop.0+0x40/0x340 include/linux/memcontrol.h:1042 count_memcg_event_mm include/linux/memcontrol.h:1052 [inline] mm_account_fault mm/memory.c:5928 [inline] handle_mm_fault+0x5cc/0xaa0 mm/memory.c:6088 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:121 [inline] RIP: 0010:raw_copy_from_user arch/x86/include/asm/uaccess_64.h:136 [inline] RIP: 0010:_inline_copy_from_user include/linux/uaccess.h:170 [inline] RIP: 0010:_copy_from_user+0xc1/0xf0 lib/usercopy.c:18 Code: 89 df e8 e2 65 fe fc 4d 85 f6 75 9e e8 28 64 fe fc 0f ae e8 89 ee 4c 89 ef e8 2b dc 5f fd 0f 01 cb 48 89 e9 4c 89 ef 48 89 de a4 0f 1f 00 48 89 cb 0f 01 ca e9 73 ff ff ff e8 fa 63 fe fc 48 RSP: 0018:ffffc9000d91f9e8 EFLAGS: 00050246 RAX: 0000000000000001 RBX: 0000000020002000 RCX: 0000000000000038 RDX: fffff52001b23f4e RSI: 0000000020002000 RDI: ffffc9000d91fa38 RBP: 0000000000000038 R08: 0000000000000001 R09: fffff52001b23f4d R10: ffffc9000d91fa6f R11: 0000000000000000 R12: 0000000020002038 R13: ffffc9000d91fa38 R14: 0000000000000000 R15: ffffc9000d91fa38 copy_from_user include/linux/uaccess.h:203 [inline] copy_msghdr_from_user+0x99/0x160 net/socket.c:2532 sendmsg_copy_msghdr net/socket.c:2633 [inline] ___sys_sendmsg+0xff/0x1e0 net/socket.c:2652 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2742 __do_sys_sendmmsg net/socket.c:2771 [inline] __se_sys_sendmmsg net/socket.c:2768 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2768 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f39cdf7df39 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f39ced14038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f39ce135f80 RCX: 00007f39cdf7df39 RDX: 0400000000000026 RSI: 0000000020001cc0 RDI: 0000000000000004 RBP: 00007f39cdff0216 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f39ce135f80 R15: 00007ffda032e718 ---------------- Code disassembly (best guess): 0: c1 05 da 80 98 7e 83 roll $0x83,0x7e9880da(%rip) # 0x7e9880e1 7: f8 clc 8: 01 0f add %ecx,(%rdi) a: 85 ea test %ebp,%edx c: 02 00 add (%rax),%al e: 00 9c 58 f6 c4 02 0f add %bl,0xf02c4f6(%rax,%rbx,2) 15: 85 d5 test %edx,%ebp 17: 02 00 add (%rax),%al 19: 00 48 85 add %cl,-0x7b(%rax) 1c: ed in (%dx),%eax 1d: 74 01 je 0x20 1f: fb sti 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 48 01 c3 add %rax,%rbx <-- trapping instruction 2d: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 34: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx) 3b: 00 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 84 .byte 0x84 3f: 24 .byte 0x24