====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc7-syzkaller-00141-g43db1e03c086 #0 Not tainted ------------------------------------------------------ syz.2.466/7065 is trying to acquire lock: ffff8880b9238a80 (lock#11){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9238a80 (lock#11){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x7f/0x790 mm/mmap_lock.c:237 but task is already holding lock: ffff8880b923ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:567 [inline] ffff8880b923ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:552 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559 raw_spin_rq_lock kernel/sched/sched.h:1406 [inline] _raw_spin_rq_lock_irqsave kernel/sched/sched.h:1425 [inline] rq_lock_irqsave kernel/sched/sched.h:1686 [inline] class_rq_lock_irqsave_constructor kernel/sched/sched.h:1740 [inline] sched_mm_cid_before_execve+0x114/0x5e0 kernel/sched/core.c:12026 exit_signals+0x34d/0x960 kernel/signal.c:3014 do_exit+0x54e/0x2ba0 kernel/exit.c:835 __do_sys_exit kernel/exit.c:992 [inline] __se_sys_exit kernel/exit.c:990 [inline] __x64_sys_exit+0x42/0x50 kernel/exit.c:990 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&sighand->siglock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __lock_task_sighand+0xc2/0x340 kernel/signal.c:1412 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x290/0x300 kernel/signal.c:1451 bpf_send_signal_common+0x2e8/0x3a0 kernel/trace/bpf_trace.c:881 ____bpf_send_signal_thread kernel/trace/bpf_trace.c:898 [inline] bpf_send_signal_thread+0x16/0x20 kernel/trace/bpf_trace.c:896 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:2011 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2252 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2446 __bpf_trace_mmap_lock_acquire_returned+0x134/0x180 include/trace/events/mmap_lock.h:52 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline] __mmap_lock_do_trace_acquire_returned+0x456/0x790 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:164 [inline] get_mmap_lock_carefully mm/memory.c:5716 [inline] lock_mm_and_find_vma+0xeb/0x6a0 mm/memory.c:5776 do_user_addr_fault+0x29c/0xe50 arch/x86/mm/fault.c:1361 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:65 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline] _copy_to_user lib/usercopy.c:46 [inline] _copy_to_user+0xac/0xc0 lib/usercopy.c:39 copy_to_user include/linux/uaccess.h:191 [inline] rng_dev_read+0x25d/0x720 drivers/char/hw_random/core.c:252 do_loop_readv_writev fs/read_write.c:761 [inline] do_loop_readv_writev fs/read_write.c:749 [inline] vfs_readv+0x6cb/0x8a0 fs/read_write.c:934 do_preadv fs/read_write.c:1049 [inline] __do_sys_preadv fs/read_write.c:1099 [inline] __se_sys_preadv fs/read_write.c:1094 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1094 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (lock#11){+.+.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x97/0x790 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:164 [inline] stack_map_get_build_id_offset+0x5d9/0x7c0 kernel/bpf/stackmap.c:141 __bpf_get_stack+0x6bf/0x700 kernel/bpf/stackmap.c:449 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1994 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1984 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:2011 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2252 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2444 __bpf_trace_tlb_flush+0xd2/0x110 include/trace/events/tlb.h:38 trace_tlb_flush+0xf3/0x170 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x68b/0xbc0 arch/x86/mm/tlb.c:642 context_switch kernel/sched/core.c:5392 [inline] __schedule+0xd2b/0x5d00 kernel/sched/core.c:6745 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] class_preempt_destructor include/linux/preempt.h:480 [inline] try_to_wake_up+0xc08/0x13e0 kernel/sched/core.c:4233 wake_up_process kernel/sched/core.c:4510 [inline] wake_up_q+0x91/0x140 kernel/sched/core.c:1029 futex_wake+0x43e/0x4e0 kernel/futex/waitwake.c:199 do_futex+0x1e5/0x350 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex kernel/futex/syscalls.c:160 [inline] __x64_sys_futex+0x1e1/0x4c0 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: lock#11 --> &sighand->siglock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&sighand->siglock); lock(&rq->__lock); lock(lock#11); *** DEADLOCK *** 3 locks held by syz.2.466/7065: #0: ffff8880b923ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:567 [inline] #0: ffff8880b923ebd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:552 #1: ffffffff8dbb1620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8dbb1620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8dbb1620 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #1: ffffffff8dbb1620 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2444 #2: ffff88807ffa4418 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #2: ffff88807ffa4418 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x1e8/0x7c0 kernel/bpf/stackmap.c:141 stack backtrace: CPU: 0 PID: 7065 Comm: syz.2.466 Not tainted 6.10.0-rc7-syzkaller-00141-g43db1e03c086 #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+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x97/0x790 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:164 [inline] stack_map_get_build_id_offset+0x5d9/0x7c0 kernel/bpf/stackmap.c:141 __bpf_get_stack+0x6bf/0x700 kernel/bpf/stackmap.c:449 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1994 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1984 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:2011 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2252 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2444 __bpf_trace_tlb_flush+0xd2/0x110 include/trace/events/tlb.h:38 trace_tlb_flush+0xf3/0x170 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x68b/0xbc0 arch/x86/mm/tlb.c:642 context_switch kernel/sched/core.c:5392 [inline] __schedule+0xd2b/0x5d00 kernel/sched/core.c:6745 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] class_preempt_destructor include/linux/preempt.h:480 [inline] try_to_wake_up+0xc08/0x13e0 kernel/sched/core.c:4233 wake_up_process kernel/sched/core.c:4510 [inline] wake_up_q+0x91/0x140 kernel/sched/core.c:1029 futex_wake+0x43e/0x4e0 kernel/futex/waitwake.c:199 do_futex+0x1e5/0x350 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex kernel/futex/syscalls.c:160 [inline] __x64_sys_futex+0x1e1/0x4c0 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fae3ed75bd9 Code: Unable to access opcode bytes at 0x7fae3ed75baf. RSP: 002b:00007fae3fae40f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fae3ef03f68 RCX: 00007fae3ed75bd9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fae3ef03f6c RBP: 00007fae3ef03f60 R08: 00007fae3fae5080 R09: 00007fae3fae46c0 R10: 0000000000000005 R11: 0000000000000246 R12: 00007fae3ef03f6c R13: 000000000000000b R14: 00007fff1d81b6d0 R15: 00007fff1d81b7b8