====================================================== WARNING: possible circular locking dependency detected 6.1.93-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/3566 is trying to acquire lock: ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 but task is already holding lock: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 raw_spin_rq_lock kernel/sched/sched.h:1354 [inline] rq_lock kernel/sched/sched.h:1644 [inline] task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11884 sched_cgroup_fork+0x374/0x400 kernel/sched/core.c:4686 copy_process+0x2442/0x4060 kernel/fork.c:2384 kernel_clone+0x222/0x920 kernel/fork.c:2682 user_mode_thread+0x12e/0x190 kernel/fork.c:2758 rest_init+0x23/0x300 init/main.c:699 start_kernel+0x0/0x53f init/main.c:894 start_kernel+0x496/0x53f init/main.c:1141 secondary_startup_64_no_verify+0xcf/0xdb -> #2 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112 signal_wake_up_state kernel/signal.c:780 [inline] signal_wake_up include/linux/sched/signal.h:457 [inline] complete_signal+0x796/0xbd0 kernel/signal.c:1074 __send_signal_locked+0xb1a/0xdc0 kernel/signal.c:1194 do_notify_parent+0xe2b/0x1100 kernel/signal.c:2120 exit_notify kernel/exit.c:744 [inline] do_exit+0x172e/0x26a0 kernel/exit.c:889 do_group_exit+0x202/0x2b0 kernel/exit.c:1019 __do_sys_exit_group kernel/exit.c:1030 [inline] __se_sys_exit_group kernel/exit.c:1028 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&sighand->siglock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 __lock_task_sighand+0x145/0x2d0 kernel/signal.c:1410 lock_task_sighand include/linux/sched/signal.h:745 [inline] do_send_sig_info kernel/signal.c:1299 [inline] group_send_sig_info+0x26c/0x300 kernel/signal.c:1448 bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:882 ____bpf_send_signal kernel/trace/bpf_trace.c:887 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:885 0xffffffffa000096a bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline] bpf_trace_run4+0x3c3/0x470 kernel/trace/bpf_trace.c:2314 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline] __mmap_lock_do_trace_acquire_returned+0x5e3/0x670 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] get_mmap_lock_carefully mm/memory.c:5304 [inline] lock_mm_and_find_vma+0x219/0x2e0 mm/memory.c:5366 do_user_addr_fault arch/x86/mm/fault.c:1312 [inline] handle_page_fault arch/x86/mm/fault.c:1431 [inline] exc_page_fault+0x169/0x620 arch/x86/mm/fault.c:1487 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 -> #0 (lock#10){+.+.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867 bpf_prog_ec3b2eefa702d8d3+0x3a/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline] bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2312 trace_tlb_flush+0x151/0x1a0 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x84a/0xc20 context_switch kernel/sched/core.c:5230 [inline] __schedule+0x1140/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 __might_fault+0xbd/0x110 mm/memory.c:5835 _copy_to_user+0x26/0x130 lib/usercopy.c:36 copy_to_user include/linux/uaccess.h:169 [inline] copy_entries_to_user net/ipv4/netfilter/ip_tables.c:837 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1024 [inline] do_ipt_get_ctl+0xfb1/0x1890 net/ipv4/netfilter/ip_tables.c:1670 nf_getsockopt+0x28e/0x2b0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x21a/0x2d0 net/ipv4/ip_sockglue.c:1826 tcp_getsockopt+0x15c/0x1c0 net/ipv4/tcp.c:4445 __sys_getsockopt+0x2b2/0x5d0 net/socket.c:2327 __do_sys_getsockopt net/socket.c:2342 [inline] __se_sys_getsockopt net/socket.c:2339 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2339 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: lock#10 --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock(lock#10); *** DEADLOCK *** 5 locks held by syz-executor.2/3566: #0: ffff888027efa308 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x48/0x3a0 net/netfilter/x_tables.c:1242 #1: ffff888027c0c4d8 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0xa1/0x110 mm/memory.c:5835 #2: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #3: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #3: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline] #3: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x110/0x410 kernel/trace/bpf_trace.c:2312 #4: ffff888027c0c4d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #4: ffff888027c0c4d8 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x232/0x9c0 kernel/bpf/stackmap.c:144 stack backtrace: CPU: 0 PID: 3566 Comm: syz-executor.2 Not tainted 6.1.93-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867 bpf_prog_ec3b2eefa702d8d3+0x3a/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline] bpf_trace_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2312 trace_tlb_flush+0x151/0x1a0 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x84a/0xc20 context_switch kernel/sched/core.c:5230 [inline] __schedule+0x1140/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 cf aa 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003f1f760 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007e3ef8 RCX: ffffffff816b2002 RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d4520 RBP: ffffc90003f1f8b0 R08: dffffc0000000000 R09: fffffbfff2093a4b R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007e3ef4 R13: dffffc0000000000 R14: ffffc90003f1f7c0 R15: 0000000000000246 __might_fault+0xbd/0x110 mm/memory.c:5835 _copy_to_user+0x26/0x130 lib/usercopy.c:36 copy_to_user include/linux/uaccess.h:169 [inline] copy_entries_to_user net/ipv4/netfilter/ip_tables.c:837 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1024 [inline] do_ipt_get_ctl+0xfb1/0x1890 net/ipv4/netfilter/ip_tables.c:1670 nf_getsockopt+0x28e/0x2b0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x21a/0x2d0 net/ipv4/ip_sockglue.c:1826 tcp_getsockopt+0x15c/0x1c0 net/ipv4/tcp.c:4445 __sys_getsockopt+0x2b2/0x5d0 net/socket.c:2327 __do_sys_getsockopt net/socket.c:2342 [inline] __se_sys_getsockopt net/socket.c:2339 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2339 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4f13e7ea4a Code: Unable to access opcode bytes at 0x7f4f13e7ea20. RSP: 002b:00007ffd2e22b138 EFLAGS: 00000212 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffd2e22b1c0 RCX: 00007f4f13e7ea4a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffd2e22b15c R09: 00007ffd2e22b577 R10: 00007ffd2e22b1c0 R11: 0000000000000212 R12: 00007f4f13f85a80 R13: 00007ffd2e22b15c R14: 0000000000000000 R15: 00007f4f13f86ec0 ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 cf aa 77 00 call 0x77aadb c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 84 01 00 00 jne 0x19b 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25