====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-00242-g36534d3c5453 #0 Not tainted ------------------------------------------------------ syz-executor.3/5221 is trying to acquire lock: ffff8880b9438828 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9438828 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x8f/0x630 mm/mmap_lock.c:237 but task is already holding lock: ffff8880b9439418 (stock_lock){..-.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9439418 (stock_lock){..-.}-{2:2}, at: refill_obj_stock+0x120/0x6c0 mm/memcontrol.c:3645 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (stock_lock){..-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] consume_obj_stock mm/memcontrol.c:3546 [inline] obj_cgroup_charge+0x13e/0x630 mm/memcontrol.c:3675 __memcg_slab_post_alloc_hook+0x1b1/0x7e0 mm/memcontrol.c:3768 memcg_slab_post_alloc_hook mm/slub.c:2103 [inline] slab_post_alloc_hook mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4000 [inline] kmem_cache_alloc_noprof+0x1de/0x2a0 mm/slub.c:4007 __sigqueue_alloc+0x42e/0x540 kernel/signal.c:428 __send_signal_locked+0x22f/0xdc0 kernel/signal.c:1119 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 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_7bb747c56a8bcba8+0x11/0x25 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_write_lock_killable include/linux/mmap_lock.h:123 [inline] vm_mmap_pgoff+0x3a7/0x3d0 mm/util.c:571 ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1443 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 (&sighand->siglock){....}-{2:2}: 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_7bb747c56a8bcba8+0x11/0x25 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_write_lock_killable include/linux/mmap_lock.h:123 [inline] vm_mmap_pgoff+0x3a7/0x3d0 mm/util.c:571 ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1443 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 (lock#10){+.+.}-{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 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_prog_e6cf5f9c69743609+0x42/0x46 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_prog_run_array include/linux/bpf.h:2103 [inline] trace_call_bpf+0x369/0x8a0 kernel/trace/bpf_trace.c:147 perf_trace_run_bpf_submit+0x7c/0x1d0 kernel/events/core.c:10269 perf_trace_lock+0x388/0x490 include/trace/events/lock.h:50 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x986/0x9f0 kernel/locking/lockdep.c:5765 local_lock_release include/linux/local_lock_internal.h:38 [inline] refill_obj_stock+0x3ae/0x6c0 mm/memcontrol.c:3663 obj_cgroup_uncharge mm/memcontrol.c:3716 [inline] __memcg_slab_free_hook+0x1df/0x310 mm/memcontrol.c:3803 memcg_slab_free_hook mm/slub.c:2129 [inline] slab_free mm/slub.c:4433 [inline] kmem_cache_free+0x1cf/0x350 mm/slub.c:4511 __sigqueue_free kernel/signal.c:451 [inline] collect_signal kernel/signal.c:594 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:616 dequeue_signal+0xd8/0x5a0 kernel/signal.c:636 get_signal+0x602/0x1740 kernel/signal.c:2788 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: lock#10 --> &sighand->siglock --> stock_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(stock_lock); lock(&sighand->siglock); lock(stock_lock); lock(lock#10); *** DEADLOCK *** 4 locks held by syz-executor.3/5221: #0: ffff888021bcc0d8 (&sighand->siglock){....}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] #0: ffff888021bcc0d8 (&sighand->siglock){....}-{2:2}, at: get_signal+0x258/0x1740 kernel/signal.c:2697 #1: ffff8880b9439418 (stock_lock){..-.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #1: ffff8880b9439418 (stock_lock){..-.}-{2:2}, at: refill_obj_stock+0x120/0x6c0 mm/memcontrol.c:3645 #2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: trace_call_bpf+0xbc/0x8a0 #3: ffff88802faed718 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #3: ffff88802faed718 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x237/0x9d0 kernel/bpf/stackmap.c:141 stack backtrace: CPU: 0 PID: 5221 Comm: syz-executor.3 Not tainted 6.10.0-rc2-syzkaller-00242-g36534d3c5453 #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+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 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_prog_e6cf5f9c69743609+0x42/0x46 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_prog_run_array include/linux/bpf.h:2103 [inline] trace_call_bpf+0x369/0x8a0 kernel/trace/bpf_trace.c:147 perf_trace_run_bpf_submit+0x7c/0x1d0 kernel/events/core.c:10269 perf_trace_lock+0x388/0x490 include/trace/events/lock.h:50 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x986/0x9f0 kernel/locking/lockdep.c:5765 local_lock_release include/linux/local_lock_internal.h:38 [inline] refill_obj_stock+0x3ae/0x6c0 mm/memcontrol.c:3663 obj_cgroup_uncharge mm/memcontrol.c:3716 [inline] __memcg_slab_free_hook+0x1df/0x310 mm/memcontrol.c:3803 memcg_slab_free_hook mm/slub.c:2129 [inline] slab_free mm/slub.c:4433 [inline] kmem_cache_free+0x1cf/0x350 mm/slub.c:4511 __sigqueue_free kernel/signal.c:451 [inline] collect_signal kernel/signal.c:594 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:616 dequeue_signal+0xd8/0x5a0 kernel/signal.c:636 get_signal+0x602/0x1740 kernel/signal.c:2788 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faace07cea9 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:00007faacedd40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007faace1b3f80 RCX: 00007faace07cea9 RDX: 000000000000000c RSI: 0000000040042408 RDI: 000000000000000a RBP: 00007faace0ebff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007faace1b3f80 R15: 00007ffcf8721998