====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.2848/15472 is trying to acquire lock: ffff888023283a38 (&trie->lock){-...}-{2:2}, at: trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467 but task is already holding lock: ffff8880b9135df8 (lock){-.-.}-{2:2}, at: local_lock_acquire+0x5/0x120 include/linux/local_lock_internal.h:28 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (lock){-.-.}-{2:2}: local_lock_acquire+0x2b/0x120 include/linux/local_lock_internal.h:29 rmqueue_pcplist mm/page_alloc.c:3699 [inline] rmqueue mm/page_alloc.c:3742 [inline] get_page_from_freelist+0x141e/0x1c60 mm/page_alloc.c:4189 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 __alloc_pages_node include/linux/gfp.h:570 [inline] alloc_pages_node include/linux/gfp.h:584 [inline] kmalloc_large_node+0x7d/0x190 mm/slub.c:4426 __kmalloc_node+0x232/0x3b0 mm/slub.c:4442 kmalloc_node include/linux/slab.h:630 [inline] bpf_map_kmalloc_node+0xba/0x140 kernel/bpf/syscall.c:432 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:290 [inline] trie_update_elem+0x1cc/0xc50 kernel/bpf/lpm_trie.c:332 bpf_map_update_value+0x57d/0x650 kernel/bpf/syscall.c:223 map_update_elem+0x626/0x770 kernel/bpf/syscall.c:1194 __sys_bpf+0x3fb/0x670 kernel/bpf/syscall.c:4645 __do_sys_bpf kernel/bpf/syscall.c:4761 [inline] __se_sys_bpf kernel/bpf/syscall.c:4759 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&trie->lock){-...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467 bpf_prog_2c29ac5cdc6b1842+0x3a/0x504 bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline] bpf_trace_run1+0x153/0x2d0 kernel/trace/bpf_trace.c:1914 __bpf_trace_mm_page_free_batched+0x41/0x60 include/trace/events/kmem.h:182 trace_mm_page_free_batched include/trace/events/kmem.h:182 [inline] free_unref_page_list+0x6bb/0x7e0 mm/page_alloc.c:3465 release_pages+0x184b/0x1bb0 mm/swap.c:963 __pagevec_release+0x6d/0xe0 mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x5cb/0x1880 mm/shmem.c:964 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_fallocate+0x3f3/0xe20 mm/shmem.c:2698 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ioctl_preallocate fs/ioctl.c:294 [inline] file_ioctl fs/ioctl.c:-1 [inline] do_vfs_ioctl+0x1b70/0x1de0 fs/ioctl.c:853 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock); lock(&trie->lock); lock(lock); lock(&trie->lock); *** DEADLOCK *** 4 locks held by syz.0.2848/15472: #0: ffff88801fd7e460 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff88801fd7e460 (sb_writers#3){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff88805c098ee8 (&sb->s_type->i_mutex_key#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88805c098ee8 (&sb->s_type->i_mutex_key#8){+.+.}-{3:3}, at: shmem_fallocate+0x153/0xe20 mm/shmem.c:2674 #2: ffff8880b9135df8 (lock){-.-.}-{2:2}, at: local_lock_acquire+0x5/0x120 include/linux/local_lock_internal.h:28 #3: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312 stack backtrace: CPU: 1 PID: 15472 Comm: syz.0.2848 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467 bpf_prog_2c29ac5cdc6b1842+0x3a/0x504 bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline] bpf_trace_run1+0x153/0x2d0 kernel/trace/bpf_trace.c:1914 __bpf_trace_mm_page_free_batched+0x41/0x60 include/trace/events/kmem.h:182 trace_mm_page_free_batched include/trace/events/kmem.h:182 [inline] free_unref_page_list+0x6bb/0x7e0 mm/page_alloc.c:3465 release_pages+0x184b/0x1bb0 mm/swap.c:963 __pagevec_release+0x6d/0xe0 mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x5cb/0x1880 mm/shmem.c:964 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_fallocate+0x3f3/0xe20 mm/shmem.c:2698 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ioctl_preallocate fs/ioctl.c:294 [inline] file_ioctl fs/ioctl.c:-1 [inline] do_vfs_ioctl+0x1b70/0x1de0 fs/ioctl.c:853 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fb52b593749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb5297fa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb52b7e9fa0 RCX: 00007fb52b593749 RDX: 0000200000000040 RSI: 0000000040305829 RDI: 0000000000000003 RBP: 00007fb52b617f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb52b7ea038 R14: 00007fb52b7e9fa0 R15: 00007ffc82bc9d48