===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.1.84-syzkaller #0 Not tainted ----------------------------------------------------- syz-fuzzer/3538 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire: ffff88807905c240 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:416 [inline] ffff88807905c240 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 and this task is already holding: ffff888026620958 (&sighand->siglock){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] ffff888026620958 (&sighand->siglock){-.-.}-{2:2}, at: get_signal+0x242/0x17d0 kernel/signal.c:2655 which would create a new lock dependency: (&sighand->siglock){-.-.}-{2:2} -> (&stab->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+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 do_bpf_send_signal+0x81/0x150 kernel/trace/bpf_trace.c:839 irq_work_single+0xd5/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x187/0x350 kernel/irq_work.c:251 __sysvec_irq_work+0xbb/0x360 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x89/0xb0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:679 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x154b/0x17d0 kernel/signal.c:2865 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd to a HARDIRQ-irq-unsafe lock: (&stab->lock){+...}-{2:2} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:416 [inline] sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 0xffffffffa0001fce 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_test_run+0x60c/0x8b0 net/bpf/test_run.c:402 bpf_prog_test_run_skb+0xaf1/0x13a0 net/bpf/test_run.c:1180 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3670 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5023 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&stab->lock); local_irq_disable(); lock(&sighand->siglock); lock(&stab->lock); lock(&sighand->siglock); *** DEADLOCK *** 2 locks held by syz-fuzzer/3538: #0: ffff888026620958 (&sighand->siglock){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] #0: ffff888026620958 (&sighand->siglock){-.-.}-{2:2}, at: get_signal+0x242/0x17d0 kernel/signal.c:2655 #1: ffffffff8d12a980 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8d12a980 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8d12a980 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline] #1: ffffffff8d12a980 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0x146/0x440 kernel/trace/bpf_trace.c:2313 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&sighand->siglock){-.-.}-{2:2} { IN-HARDIRQ-W at: 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 do_bpf_send_signal+0x81/0x150 kernel/trace/bpf_trace.c:839 irq_work_single+0xd5/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x187/0x350 kernel/irq_work.c:251 __sysvec_irq_work+0xbb/0x360 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x89/0xb0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:679 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x154b/0x17d0 kernel/signal.c:2865 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd IN-SOFTIRQ-W at: 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 bpf_prog_8cc4ff36b5985b6a+0x9/0x17 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_run3+0x231/0x440 kernel/trace/bpf_trace.c:2313 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:114 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x418/0x510 mm/slub.c:3682 rcu_do_batch kernel/rcu/tree.c:2296 [inline] rcu_core+0xad4/0x17e0 kernel/rcu/tree.c:2556 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 kasan_check_range+0x1ac/0x290 mm/kasan/generic.c:189 memset+0x1f/0x40 mm/kasan/shadow.c:44 unwind_next_frame+0xde7/0x2220 arch/x86/kernel/unwind_orc.c:546 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 tomoyo_path_perm+0x584/0x710 security/tomoyo/file.c:842 security_inode_getattr+0xcf/0x120 security/security.c:1361 vfs_getattr+0x26/0x360 fs/stat.c:158 vfs_statx+0x194/0x4b0 fs/stat.c:233 vfs_fstatat fs/stat.c:267 [inline] __do_sys_newfstatat fs/stat.c:437 [inline] __se_sys_newfstatat fs/stat.c:431 [inline] __x64_sys_newfstatat+0x151/0x1e0 fs/stat.c:431 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd INITIAL USE at: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] calculate_sigpending+0x4a/0x80 kernel/signal.c:195 ret_from_fork+0x8/0x30 arch/x86/entry/entry_64.S:292 } ... key at: [] sighand_ctor.__key+0x0/0x20 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&stab->lock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:416 [inline] sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 0xffffffffa0001fce 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_test_run+0x60c/0x8b0 net/bpf/test_run.c:402 bpf_prog_test_run_skb+0xaf1/0x13a0 net/bpf/test_run.c:1180 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3670 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5023 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd INITIAL USE at: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:416 [inline] sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 0xffffffffa0001fce 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_test_run+0x60c/0x8b0 net/bpf/test_run.c:402 bpf_prog_test_run_skb+0xaf1/0x13a0 net/bpf/test_run.c:1180 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3670 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5023 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd } ... key at: [] sock_map_alloc.__key+0x0/0x20 ... acquired at: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:416 [inline] sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 bpf_prog_2c29ac5cdc6b1842+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_run3+0x231/0x440 kernel/trace/bpf_trace.c:2313 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:114 __traceiter_kmem_cache_free+0x2e/0x50 include/trace/events/kmem.h:114 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x418/0x510 mm/slub.c:3682 __sigqueue_free kernel/signal.c:458 [inline] collect_signal kernel/signal.c:601 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:623 dequeue_signal+0x165/0x590 kernel/signal.c:646 get_signal+0x5f2/0x17d0 kernel/signal.c:2742 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd stack backtrace: CPU: 1 PID: 3538 Comm: syz-fuzzer Not tainted 6.1.84-syzkaller #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+0x1e3/0x2cb lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2604 [inline] check_irq_usage kernel/locking/lockdep.c:2843 [inline] check_prev_add kernel/locking/lockdep.c:3094 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x4d16/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 __sock_map_delete net/core/sock_map.c:416 [inline] sock_map_delete_elem+0x97/0x130 net/core/sock_map.c:448 bpf_prog_2c29ac5cdc6b1842+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_run3+0x231/0x440 kernel/trace/bpf_trace.c:2313 __bpf_trace_kmem_cache_free+0x99/0xc0 include/trace/events/kmem.h:114 __traceiter_kmem_cache_free+0x2e/0x50 include/trace/events/kmem.h:114 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline] kmem_cache_free+0x418/0x510 mm/slub.c:3682 __sigqueue_free kernel/signal.c:458 [inline] collect_signal kernel/signal.c:601 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:623 dequeue_signal+0x165/0x590 kernel/signal.c:646 get_signal+0x5f2/0x17d0 kernel/signal.c:2742 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x471e77 Code: 8b 44 24 20 b9 40 42 0f 00 f7 f1 48 89 04 24 b8 e8 03 00 00 f7 e2 48 89 44 24 08 48 89 e7 be 00 00 00 00 b8 23 00 00 00 0f 05 <48> 83 c4 10 5d c3 cc cc cc b8 ba 00 00 00 0f 05 89 44 24 08 c3 cc RSP: 002b:000000c000069f18 EFLAGS: 00000202 RAX: fffffffffffffffc RBX: 0000000000002710 RCX: 0000000000471e77 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000c000069f18 RBP: 000000c000069f28 R08: 00007ffcf71500b0 R09: 0000000000000010 R10: 00007ffcf7150080 R11: 0000000000000202 R12: 000000c000069f18 R13: 000000c000f4f400 R14: 000000c0000064e0 R15: 000000000000000a