====================================================== WARNING: possible circular locking dependency detected 6.1.92-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/5080 is trying to acquire lock: ffff88801274a7d8 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112 but task is already holding lock: ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (lock#10){+.+.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x9d/0x670 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:137 [inline] stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867 0xffffffffa0001fe6 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_run2+0x1fd/0x410 kernel/trace/bpf_trace.c:2312 trace_tlb_flush+0x151/0x1a0 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x84a/0xc20 context_switch kernel/sched/core.c:5230 [inline] __schedule+0x1140/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 do_nanosleep+0x192/0x5f0 kernel/time/hrtimer.c:2045 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1308 [inline] __se_sys_clock_nanosleep+0x323/0x3b0 kernel/time/posix-timers.c:1285 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 raw_spin_rq_lock kernel/sched/sched.h:1354 [inline] rq_lock kernel/sched/sched.h:1644 [inline] task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11869 sched_cgroup_fork+0x374/0x400 kernel/sched/core.c:4686 copy_process+0x2442/0x4060 kernel/fork.c:2384 kernel_clone+0x222/0x920 kernel/fork.c:2682 user_mode_thread+0x12e/0x190 kernel/fork.c:2758 rest_init+0x23/0x300 init/main.c:699 start_kernel+0x0/0x53f init/main.c:894 start_kernel+0x496/0x53f init/main.c:1141 secondary_startup_64_no_verify+0xcf/0xdb -> #0 (&p->pi_lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 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_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112 rcu_read_unlock_special+0x3d2/0x540 kernel/rcu/tree_plugin.h:655 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] put_memcg_path_buf+0xde/0x110 mm/mmap_lock.c:153 __mmap_lock_do_trace_acquire_returned+0x1f7/0x670 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:137 [inline] get_mmap_lock_carefully mm/memory.c:5304 [inline] lock_mm_and_find_vma+0x219/0x2e0 mm/memory.c:5366 do_user_addr_fault arch/x86/mm/fault.c:1343 [inline] handle_page_fault arch/x86/mm/fault.c:1462 [inline] exc_page_fault+0x169/0x660 arch/x86/mm/fault.c:1518 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:165 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] copyin lib/iov_iter.c:183 [inline] _copy_from_iter+0x2c2/0xff0 lib/iov_iter.c:631 copy_page_from_iter+0x76/0x100 lib/iov_iter.c:752 pipe_write+0x857/0x1af0 fs/pipe.c:537 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7ae/0xba0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: &p->pi_lock --> &rq->__lock --> lock#10 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock#10); lock(&rq->__lock); lock(lock#10); lock(&p->pi_lock); *** DEADLOCK *** 4 locks held by syz-executor.1/5080: #0: ffff88807bd80468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] #0: ffff88807bd80468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0xd92/0x1af0 fs/pipe.c:577 #1: ffff8880266735d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #1: ffff8880266735d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5304 [inline] #1: ffff8880266735d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2e0 mm/memory.c:5366 #2: ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #2: ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: get_memcg_path_buf mm/mmap_lock.c:139 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: get_mm_memcg_path+0xb1/0x600 mm/mmap_lock.c:209 stack backtrace: CPU: 1 PID: 5080 Comm: syz-executor.1 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 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_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112 rcu_read_unlock_special+0x3d2/0x540 kernel/rcu/tree_plugin.h:655 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] put_memcg_path_buf+0xde/0x110 mm/mmap_lock.c:153 __mmap_lock_do_trace_acquire_returned+0x1f7/0x670 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:137 [inline] get_mmap_lock_carefully mm/memory.c:5304 [inline] lock_mm_and_find_vma+0x219/0x2e0 mm/memory.c:5366 do_user_addr_fault arch/x86/mm/fault.c:1343 [inline] handle_page_fault arch/x86/mm/fault.c:1462 [inline] exc_page_fault+0x169/0x660 arch/x86/mm/fault.c:1518 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166 Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 0a 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90014167938 EFLAGS: 00050206 RAX: ffffffff84363901 RBX: 0000000000001000 RCX: 00000000000001c0 RDX: 0000000000001000 RSI: 0000000020558000 RDI: ffff8880234d4e40 RBP: ffffc90014167a98 R08: dffffc0000000000 R09: ffffed100469aa00 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880234d4000 R13: 1ffff9200282cfb3 R14: 0000000000001000 R15: dffffc0000000000 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] copyin lib/iov_iter.c:183 [inline] _copy_from_iter+0x2c2/0xff0 lib/iov_iter.c:631 copy_page_from_iter+0x76/0x100 lib/iov_iter.c:752 pipe_write+0x857/0x1af0 fs/pipe.c:537 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7ae/0xba0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fae69c7cf69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fae6aa490c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fae69db3f80 RCX: 00007fae69c7cf69 RDX: 00000000fffffdef RSI: 00000000200001c0 RDI: 0000000000000000 RBP: 00007fae69cda6fe R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fae69db3f80 R15: 00007ffca54d3838 ---------------- Code disassembly (best guess): 0: ff c9 dec %ecx 2: 75 f2 jne 0xfffffff6 4: 89 d1 mov %edx,%ecx 6: c1 e9 03 shr $0x3,%ecx 9: 83 e2 07 and $0x7,%edx c: f3 48 a5 rep movsq %ds:(%rsi),%es:(%rdi) f: 89 d1 mov %edx,%ecx 11: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 13: 31 c0 xor %eax,%eax 15: 0f 01 ca clac 18: c3 ret 19: 8d 0c ca lea (%rdx,%rcx,8),%ecx 1c: 89 ca mov %ecx,%edx 1e: eb 20 jmp 0x40 20: 0f 01 cb stac 23: 83 fa 40 cmp $0x40,%edx 26: 72 38 jb 0x60 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 89 ca mov %ecx,%edx 34: eb 0a jmp 0x40 36: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 3d: 00 00 00