===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.8.0-syzkaller-05236-g443574b03387 #0 Not tainted ----------------------------------------------------- syz-fuzzer/6071 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: ffff888056096068 (&htab->buckets[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888056096068 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0xb0/0x300 net/core/sock_map.c:939 and this task is already holding: ffff888027361bd8 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 which would create a new lock dependency: ( &sighand->siglock){-.-.}-{2:2} -> ( &htab->buckets[i].lock){+...}-{2:2} but this new dependency connects a HARDIRQ-irq-safe lock: (&sighand->siglock ){-.-.}-{2:2} ... which became HARDIRQ-irq-safe at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe2/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xa8/0x3e0 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] signalfd_dequeue fs/signalfd.c:171 [inline] signalfd_read+0x419/0x15f0 fs/signalfd.c:217 vfs_read+0x204/0xb70 fs/read_write.c:474 ksys_read+0x1a0/0x2c0 fs/read_write.c:619 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 to a HARDIRQ-irq-unsafe lock: ( &htab->buckets[i].lock){+...}-{2:2} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_update_common+0x20c/0xa30 net/core/sock_map.c:1007 sock_map_update_elem_sys+0x5a4/0x910 net/core/sock_map.c:581 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&htab->buckets[i].lock); local_irq_disable(); lock(&sighand->siglock); lock(&htab->buckets[i].lock); lock(&sighand->siglock); *** DEADLOCK *** 3 locks held by syz-fuzzer/6071: #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #0: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420 #1: ffff888027361bd8 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16e/0x490 kernel/trace/bpf_trace.c:2422 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&sighand->siglock){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe2/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xa8/0x3e0 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] signalfd_dequeue fs/signalfd.c:171 [inline] signalfd_read+0x419/0x15f0 fs/signalfd.c:217 vfs_read+0x204/0xb70 fs/read_write.c:474 ksys_read+0x1a0/0x2c0 fs/read_write.c:619 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 IN-SOFTIRQ-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __lock_task_sighand+0x149/0x2e0 kernel/signal.c:1414 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 0xffffffffa00020f5 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:650 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run3+0x3b5/0x460 kernel/trace/bpf_trace.c:2421 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x23c/0x2a0 mm/slub.c:4362 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline] arch_local_irq_enable arch/x86/include/asm/irqflags.h:77 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1397 [inline] finish_lock_switch kernel/sched/core.c:5163 [inline] finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5281 context_switch kernel/sched/core.c:5412 [inline] __schedule+0x17db/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 do_nanosleep+0x197/0x600 kernel/time/hrtimer.c:2051 hrtimer_nanosleep+0x227/0x470 kernel/time/hrtimer.c:2104 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep+0x32b/0x3c0 kernel/time/posix-timers.c:1373 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] calculate_sigpending+0x4f/0x90 kernel/signal.c:188 ret_from_fork+0x24/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 } ... key at: [] sighand_ctor.__key+0x0/0x20 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&htab->buckets[i].lock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_update_common+0x20c/0xa30 net/core/sock_map.c:1007 sock_map_update_elem_sys+0x5a4/0x910 net/core/sock_map.c:581 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_update_common+0x20c/0xa30 net/core/sock_map.c:1007 sock_map_update_elem_sys+0x5a4/0x910 net/core/sock_map.c:581 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5619 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 } ... key at: [] sock_hash_alloc.__key+0x0/0x20 ... acquired at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_delete_elem+0xb0/0x300 net/core/sock_map.c:939 bpf_prog_a8aaa52f2e199321+0x4a/0x4e bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run4+0x25a/0x490 kernel/trace/bpf_trace.c:2422 trace_mm_page_alloc include/trace/events/kmem.h:177 [inline] __alloc_pages+0x657/0x680 mm/page_alloc.c:4591 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd1b/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc+0x250/0x350 mm/slub.c:3867 __sigqueue_alloc+0x42e/0x540 kernel/signal.c:428 __send_signal_locked+0x22f/0xdc0 kernel/signal.c:1119 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_8cc4ff36b5985b6a+0x1d/0x1f bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work+0x153/0x170 kernel/entry/common.c:163 syscall_exit_to_user_mode_prepare kernel/entry/common.c:194 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x273/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 stack backtrace: CPU: 0 PID: 6071 Comm: syz-fuzzer Not tainted 6.8.0-syzkaller-05236-g443574b03387 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline] check_irq_usage kernel/locking/lockdep.c:2865 [inline] check_prev_add kernel/locking/lockdep.c:3138 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x4dc7/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_delete_elem+0xb0/0x300 net/core/sock_map.c:939 bpf_prog_a8aaa52f2e199321+0x4a/0x4e bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run4+0x25a/0x490 kernel/trace/bpf_trace.c:2422 trace_mm_page_alloc include/trace/events/kmem.h:177 [inline] __alloc_pages+0x657/0x680 mm/page_alloc.c:4591 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd1b/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc+0x250/0x350 mm/slub.c:3867 __sigqueue_alloc+0x42e/0x540 kernel/signal.c:428 __send_signal_locked+0x22f/0xdc0 kernel/signal.c:1119 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1453 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_8cc4ff36b5985b6a+0x1d/0x1f bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_sys_exit include/trace/events/syscalls.h:44 [inline] syscall_exit_work+0x153/0x170 kernel/entry/common.c:163 syscall_exit_to_user_mode_prepare kernel/entry/common.c:194 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x273/0x360 kernel/entry/common.c:212 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x40720e Code: 48 83 ec 38 e8 13 00 00 00 48 83 c4 38 5d c3 cc cc cc cc cc cc cc cc cc cc cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48 RSP: 002b:000000c001e0b748 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000004 RCX: 000000000040720e RDX: 0000000000000080 RSI: 000000c001e0b818 RDI: 0000000000000004 RBP: 000000c001e0b790 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000003e6 R11: 0000000000000246 R12: 000000c001e0b820 R13: 0000000000000001 R14: 000000c000f14820 R15: 0000000000000000