================================ WARNING: inconsistent lock state 6.7.0-rc1-next-20231117-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. sshd/5054 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff888025a81bd8 (&sighand->siglock){+.?.}-{2:2}, at: __lock_task_sighand+0xc2/0x340 kernel/signal.c:1422 {SOFTIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __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] class_spinlock_constructor include/linux/spinlock.h:530 [inline] ptrace_set_stopped kernel/ptrace.c:391 [inline] ptrace_attach+0x401/0x650 kernel/ptrace.c:478 __do_sys_ptrace+0x204/0x230 kernel/ptrace.c:1290 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a irq event stamp: 187171 hardirqs last enabled at (187170): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (187170): [] _raw_spin_unlock_irqrestore+0x4e/0x70 kernel/locking/spinlock.c:194 hardirqs last disabled at (187171): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (187171): [] _raw_spin_lock_irqsave+0x4e/0x50 kernel/locking/spinlock.c:162 softirqs last enabled at (187118): [] tcp_sendmsg+0x38/0x40 net/ipv4/tcp.c:1341 softirqs last disabled at (187157): [] invoke_softirq kernel/softirq.c:427 [inline] softirqs last disabled at (187157): [] __irq_exit_rcu kernel/softirq.c:632 [inline] softirqs last disabled at (187157): [] irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sighand->siglock); lock(&sighand->siglock); *** DEADLOCK *** 3 locks held by sshd/5054: #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2152 [inline] #0: ffffffff8cfacf40 (rcu_callback){....}-{0:0}, at: rcu_core+0x7cc/0x16b0 kernel/rcu/tree.c:2431 #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2310 [inline] #1: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xe4/0x410 kernel/trace/bpf_trace.c:2350 #2: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #2: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #2: ffffffff8cfad060 (rcu_read_lock){....}-{1:2}, at: __lock_task_sighand+0x3f/0x340 kernel/signal.c:1405 stack backtrace: CPU: 1 PID: 5054 Comm: sshd Not tainted 6.7.0-rc1-next-20231117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:3970 [inline] valid_state kernel/locking/lockdep.c:4012 [inline] mark_lock_irq kernel/locking/lockdep.c:4215 [inline] mark_lock+0x91a/0xc50 kernel/locking/lockdep.c:4677 mark_usage kernel/locking/lockdep.c:4566 [inline] __lock_acquire+0x13c2/0x3b10 kernel/locking/lockdep.c:5090 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1b1/0x530 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 __lock_task_sighand+0xc2/0x340 kernel/signal.c:1422 lock_task_sighand include/linux/sched/signal.h:748 [inline] do_send_sig_info kernel/signal.c:1309 [inline] group_send_sig_info+0x288/0x300 kernel/signal.c:1460 bpf_send_signal_common+0x2e4/0x3a0 kernel/trace/bpf_trace.c:877 ____bpf_send_signal kernel/trace/bpf_trace.c:882 [inline] bpf_send_signal+0x19/0x20 kernel/trace/bpf_trace.c:880 bpf_prog_a7bf4e27797d188e+0x22/0x24 bpf_dispatcher_nop_func include/linux/bpf.h:1196 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run include/linux/filter.h:658 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2311 [inline] bpf_trace_run2+0x14e/0x410 kernel/trace/bpf_trace.c:2350 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0xf6/0x150 mm/slab_common.c:1043 security_cred_free+0xc3/0x130 security/security.c:3018 put_cred_rcu+0x126/0x570 kernel/cred.c:118 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2431 __do_softirq+0x216/0x8d5 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb5/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 16 c8 e3 f6 48 89 df e8 ce 3f e4 f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f 01 00 00 00 e8 85 ed d5 f6 65 8b 05 a6 18 7f 75 85 c0 74 12 5b RSP: 0018:ffffc90003a9f8a8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88807688f890 RCX: 1ffffffff1e31619 RDX: 0000000000000000 RSI: ffffffff8accbfe0 RDI: ffffffff8b2f1520 RBP: 0000000000000282 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8f18e357 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffc90003a9fb20 R14: ffffc90003a9fc10 R15: ffffc90003a9fb50 free_poll_entry fs/select.c:135 [inline] poll_freewait+0xd5/0x250 fs/select.c:144 do_sys_poll+0x6ee/0xde0 fs/select.c:1016 __do_sys_ppoll fs/select.c:1121 [inline] __se_sys_ppoll fs/select.c:1101 [inline] __x64_sys_ppoll+0x256/0x2d0 fs/select.c:1101 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f812f919ad5 Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fffa31933c0 EFLAGS: 00000246 ORIG_RAX: 000000000000010f RAX: ffffffffffffffda RBX: 00000000000668a0 RCX: 00007f812f919ad5 RDX: 00007fffa31933e0 RSI: 0000000000000004 RDI: 000055a6388e4a80 RBP: 000055a6388e5240 R08: 0000000000000008 R09: 0000000000000000 R10: 00007fffa31934c8 R11: 0000000000000246 R12: 000055a636970aa4 R13: 0000000000000001 R14: 000055a6369713e8 R15: 00007fffa3193448 ---------------- Code disassembly (best guess): 0: f5 cmc 1: 53 push %rbx 2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi 7: 48 89 fb mov %rdi,%rbx a: 48 83 c7 18 add $0x18,%rdi e: e8 16 c8 e3 f6 call 0xf6e3c829 13: 48 89 df mov %rbx,%rdi 16: e8 ce 3f e4 f6 call 0xf6e43fe9 1b: f7 c5 00 02 00 00 test $0x200,%ebp 21: 75 1f jne 0x42 23: 9c pushf 24: 58 pop %rax 25: f6 c4 02 test $0x2,%ah 28: 75 2f jne 0x59 * 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2f: e8 85 ed d5 f6 call 0xf6d5edb9 34: 65 8b 05 a6 18 7f 75 mov %gs:0x757f18a6(%rip),%eax # 0x757f18e1 3b: 85 c0 test %eax,%eax 3d: 74 12 je 0x51 3f: 5b pop %rbx