====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc1-syzkaller-00110-g45c0a209dcf2 #0 Not tainted ------------------------------------------------------ syz-executor.3/7089 is trying to acquire lock: ffff888021e56f18 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x149/0x2d0 kernel/signal.c:1412 but task is already holding lock: ffff8880b9438828 (lock#11){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9438828 (lock#11){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x8f/0x630 mm/mmap_lock.c:237 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (lock#11){+.+.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0xa8/0x630 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+0x9af/0x9d0 kernel/bpf/stackmap.c:141 __bpf_get_stack+0x4ad/0x5a0 kernel/bpf/stackmap.c:449 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1994 [inline] bpf_get_stack_raw_tp+0x1a3/0x240 kernel/trace/bpf_trace.c:1984 bpf_prog_16ecb682114cf56a+0x2/0x2a 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+0x2ec/0x540 kernel/trace/bpf_trace.c:2444 trace_tlb_flush+0x118/0x140 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x7cb/0xae0 context_switch kernel/sched/core.c:5392 [inline] __schedule+0x1066/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 stack_depot_save_flags+0x3e/0x830 lib/stackdepot.c:611 save_stack+0x109/0x1f0 mm/page_owner.c:157 __set_page_owner+0x92/0x800 mm/page_owner.c:320 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x2e2d/0x2ee0 mm/page_alloc.c:3402 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4660 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 vm_area_alloc_pages mm/vmalloc.c:3566 [inline] __vmalloc_area_node mm/vmalloc.c:3642 [inline] __vmalloc_node_range_noprof+0x971/0x1460 mm/vmalloc.c:3823 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3977 kcov_ioctl+0x59/0x630 kernel/kcov.c:705 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 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_exit_signals+0x17b/0x4b0 kernel/sched/core.c:12004 exit_signals+0x2a1/0x5c0 kernel/signal.c:3014 do_exit+0x6b4/0x27e0 kernel/exit.c:833 __do_sys_exit kernel/exit.c:990 [inline] __se_sys_exit kernel/exit.c:988 [inline] __pfx___ia32_sys_exit+0x0/0x10 kernel/exit.c:988 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&sighand->siglock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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+0x149/0x2d0 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+0x274/0x310 kernel/signal.c:1451 bpf_send_signal_common+0x2dd/0x430 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_16ecb682114cf56a+0x22/0x2a 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+0x334/0x590 kernel/trace/bpf_trace.c:2446 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline] __mmap_lock_do_trace_acquire_returned+0x5c8/0x630 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:5715 [inline] lock_mm_and_find_vma+0x213/0x2f0 mm/memory.c:5775 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:50 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:125 [inline] _copy_from_user+0x8c/0xe0 lib/usercopy.c:28 copy_from_user include/linux/uaccess.h:183 [inline] copy_msghdr_from_user+0xae/0x680 net/socket.c:2515 recvmsg_copy_msghdr net/socket.c:2770 [inline] ___sys_recvmsg net/socket.c:2842 [inline] do_recvmmsg+0x40f/0xae0 net/socket.c:2940 __sys_recvmmsg net/socket.c:3019 [inline] __do_sys_recvmmsg net/socket.c:3042 [inline] __se_sys_recvmmsg net/socket.c:3035 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3035 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &sighand->siglock --> &rq->__lock --> lock#11 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock#11); lock(&rq->__lock); lock(lock#11); lock(&sighand->siglock); *** DEADLOCK *** 5 locks held by syz-executor.3/7089: #0: ffff88807d570198 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff88807d570198 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5715 [inline] #0: ffff88807d570198 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5775 #1: ffff8880b9438828 (lock#11){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #1: ffff8880b9438828 (lock#11){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x8f/0x630 mm/mmap_lock.c:237 #2: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #2: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #2: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: get_memcg_path_buf mm/mmap_lock.c:139 [inline] #2: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: get_mm_memcg_path+0xb1/0x600 mm/mmap_lock.c:209 #3: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #3: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x244/0x590 kernel/trace/bpf_trace.c:2446 #4: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #4: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #4: ffffffff8e333f60 (rcu_read_lock){....}-{1:2}, at: __lock_task_sighand+0x29/0x2d0 kernel/signal.c:1395 stack backtrace: CPU: 0 PID: 7089 Comm: syz-executor.3 Not tainted 6.10.0-rc1-syzkaller-00110-g45c0a209dcf2 #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+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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+0x149/0x2d0 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+0x274/0x310 kernel/signal.c:1451 bpf_send_signal_common+0x2dd/0x430 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_16ecb682114cf56a+0x22/0x2a 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+0x334/0x590 kernel/trace/bpf_trace.c:2446 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline] __mmap_lock_do_trace_acquire_returned+0x5c8/0x630 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:5715 [inline] lock_mm_and_find_vma+0x213/0x2f0 mm/memory.c:5775 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:57 Code: f9 40 73 40 83 f9 08 73 21 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 RSP: 0018:ffffc9001420f930 EFLAGS: 00050206 RAX: ffffffff84af6001 RBX: 0000000020f81038 RCX: 0000000000000038 RDX: 0000000000000001 RSI: 0000000020f81000 RDI: ffffc9001420f9c0 RBP: ffffc9001420fa70 R08: ffffc9001420f9f7 R09: 1ffff92002841f3e R10: dffffc0000000000 R11: fffff52002841f3f R12: 0000000020f81000 R13: dffffc0000000000 R14: ffffc9001420f9c0 R15: 0000000000000038 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:125 [inline] _copy_from_user+0x8c/0xe0 lib/usercopy.c:28 copy_from_user include/linux/uaccess.h:183 [inline] copy_msghdr_from_user+0xae/0x680 net/socket.c:2515 recvmsg_copy_msghdr net/socket.c:2770 [inline] ___sys_recvmsg net/socket.c:2842 [inline] do_recvmmsg+0x40f/0xae0 net/socket.c:2940 __sys_recvmmsg net/socket.c:3019 [inline] __do_sys_recvmmsg net/socket.c:3042 [inline] __se_sys_recvmmsg net/socket.c:3035 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3035 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1c8287cee9 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:00007f1c836080c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f1c829b4070 RCX: 00007f1c8287cee9 RDX: 03ffffffffffff67 RSI: 0000000020002440 RDI: 0000000000000004 RBP: 00007f1c828c947f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f1c829b4070 R15: 00007ffd59698dc8 ---------------- Code disassembly (best guess): 0: f9 stc 1: 40 73 40 rex jae 0x44 4: 83 f9 08 cmp $0x8,%ecx 7: 73 21 jae 0x2a 9: 85 c9 test %ecx,%ecx b: 74 0f je 0x1c d: 8a 06 mov (%rsi),%al f: 88 07 mov %al,(%rdi) 11: 48 ff c7 inc %rdi 14: 48 ff c6 inc %rsi 17: 48 ff c9 dec %rcx 1a: 75 f1 jne 0xd 1c: c3 ret 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 28: 00 00 * 2a: 48 8b 06 mov (%rsi),%rax <-- trapping instruction 2d: 48 89 07 mov %rax,(%rdi) 30: 48 83 c6 08 add $0x8,%rsi 34: 48 83 c7 08 add $0x8,%rdi 38: 83 e9 08 sub $0x8,%ecx 3b: 74 df je 0x1c 3d: 83 f9 08 cmp $0x8,%ecx