===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.8.0-syzkaller-05236-g443574b03387 #0 Not tainted ----------------------------------------------------- syz-executor.3/12602 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: ffff8880616e3020 ( &htab->buckets[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] &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: ffff888021f03798 (&sighand->siglock){-.-.}-{2:2}, at: force_sig_info_to_task+0x68/0x580 kernel/signal.c:1334 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_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] linkwatch_sync_dev+0x17d/0x190 net/core/link_watch.c:261 netdev_run_todo+0x461/0x1000 net/core/dev.c:10567 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0x13a/0x1b0 drivers/net/tun.c:3498 __fput+0x429/0x8a0 fs/file_table.c:423 __do_sys_close fs/open.c:1557 [inline] __se_sys_close fs/open.c:1542 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1542 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_free+0x164/0x820 net/core/sock_map.c:1154 bpf_map_free_deferred+0xe6/0x110 kernel/bpf/syscall.c:734 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 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 *** 2 locks held by syz-executor.3/12602: #0: ffff888021f03798 (&sighand->siglock){-.-.}-{2:2}, at: force_sig_info_to_task+0x68/0x580 kernel/signal.c:1334 #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #1: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run5+0x197/0x4a0 kernel/trace/bpf_trace.c:2423 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_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] linkwatch_sync_dev+0x17d/0x190 net/core/link_watch.c:261 netdev_run_todo+0x461/0x1000 net/core/dev.c:10567 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0x13a/0x1b0 drivers/net/tun.c:3498 __fput+0x429/0x8a0 fs/file_table.c:423 __do_sys_close fs/open.c:1557 [inline] __se_sys_close fs/open.c:1542 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1542 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 0xffffffffa0002043 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_kfree include/trace/events/kmem.h:94 [inline] kfree+0x291/0x380 mm/slub.c:4396 security_cred_free+0xbc/0x100 security/security.c:3031 put_cred_rcu+0x69/0x2e0 kernel/cred.c:78 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 lock_acquire+0x25b/0x530 kernel/locking/lockdep.c:5758 rcu_lock_acquire include/linux/rcupdate.h:298 [inline] rcu_read_lock include/linux/rcupdate.h:750 [inline] is_bpf_text_address+0x42/0x2b0 kernel/bpf/core.c:767 kernel_text_address+0xa7/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kmem_cache_free+0x102/0x2a0 mm/slub.c:4363 file_free+0x24/0x1f0 fs/file_table.c:66 __do_sys_close fs/open.c:1557 [inline] __se_sys_close fs/open.c:1542 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1542 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_free+0x164/0x820 net/core/sock_map.c:1154 bpf_map_free_deferred+0xe6/0x110 kernel/bpf/syscall.c:734 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 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_free+0x164/0x820 net/core/sock_map.c:1154 bpf_map_free_deferred+0xe6/0x110 kernel/bpf/syscall.c:734 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 } ... 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_05fc780d7a5f93f9+0x4a/0x4e 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_run5+0x3f2/0x4a0 kernel/trace/bpf_trace.c:2423 __traceiter_signal_generate+0x94/0xf0 include/trace/events/signal.h:50 trace_signal_generate+0x194/0x200 include/trace/events/signal.h:50 __send_signal_locked+0xb44/0xdc0 kernel/signal.c:1187 force_sig_info_to_task+0x2ff/0x580 kernel/signal.c:1352 force_sig_info kernel/signal.c:1363 [inline] force_sig+0x119/0x1d0 kernel/signal.c:1679 gp_user_force_sig_segv arch/x86/kernel/traps.c:641 [inline] __exc_general_protection arch/x86/kernel/traps.c:674 [inline] exc_general_protection+0x1d1/0x5d0 arch/x86/kernel/traps.c:644 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617 stack backtrace: CPU: 1 PID: 12602 Comm: syz-executor.3 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_05fc780d7a5f93f9+0x4a/0x4e 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_run5+0x3f2/0x4a0 kernel/trace/bpf_trace.c:2423 __traceiter_signal_generate+0x94/0xf0 include/trace/events/signal.h:50 trace_signal_generate+0x194/0x200 include/trace/events/signal.h:50 __send_signal_locked+0xb44/0xdc0 kernel/signal.c:1187 force_sig_info_to_task+0x2ff/0x580 kernel/signal.c:1352 force_sig_info kernel/signal.c:1363 [inline] force_sig+0x119/0x1d0 kernel/signal.c:1679 gp_user_force_sig_segv arch/x86/kernel/traps.c:641 [inline] __exc_general_protection arch/x86/kernel/traps.c:674 [inline] exc_general_protection+0x1d1/0x5d0 arch/x86/kernel/traps.c:644 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:617 RIP: 0033:0x7faaa1a6fd39 Code: f8 77 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 89 f8 48 89 fa c5 f9 ef c0 25 ff 0f 00 00 3d e0 0f 00 00 0f 87 27 01 00 00 fd 74 0f c5 fd d7 c1 85 c0 74 5b f3 0f bc c0 e9 30 01 00 00 66 RSP: 002b:00007faaa2774858 EFLAGS: 00010283 RAX: 0000000000000999 RBX: 00007faaa2774dc0 RCX: 00007faaa1b75bc0 RDX: 9999999999999999 RSI: 00007faaa1ac9062 RDI: 9999999999999999 RBP: 000000000000000b R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000073 R13: 00007faaa2774f40 R14: 9999999999999999 R15: 0000000000000000