============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.4.1787/12658 is trying to acquire lock: ffff88805650f838 (rhashtable_bucket){-.-.}-{0:0}, at: rht_lock+0x8b/0x180 include/linux/rhashtable.h:331 but task is already holding lock: ffff88802bbf2038 (rhashtable_bucket){-.-.}-{0:0}, at: rht_lock+0x8b/0x180 include/linux/rhashtable.h:331 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(rhashtable_bucket); lock(rhashtable_bucket); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.4.1787/12658: #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: __rhashtable_insert_fast include/linux/rhashtable.h:774 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rhashtable_lookup_insert_fast include/linux/rhashtable.h:967 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: tipc_sk_insert net/tipc/socket.c:3027 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: tipc_sk_create+0x4d4/0x26a0 net/tipc/socket.c:503 #1: ffff88802bbf2038 (rhashtable_bucket){-.-.}-{0:0}, at: rht_lock+0x8b/0x180 include/linux/rhashtable.h:331 #2: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #2: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: trace_call_bpf+0xb6/0xb80 kernel/trace/bpf_trace.c:-1 #3: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #3: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline] #3: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rhtab_map_delete_elem+0x21/0x190 kernel/bpf/hashtab.c:2979 #4: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #4: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #4: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: __rhashtable_remove_fast include/linux/rhashtable.h:1137 [inline] #4: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rhashtable_remove_fast include/linux/rhashtable.h:1175 [inline] #4: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rhtab_delete_elem+0x15c/0x1b30 kernel/bpf/hashtab.c:-1 stack backtrace: CPU: 0 UID: 0 PID: 12658 Comm: syz.4.1787 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain kernel/locking/lockdep.c:3895 [inline] __lock_acquire+0x24df/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 rht_lock+0xa3/0x180 include/linux/rhashtable.h:331 __rhashtable_remove_fast_one include/linux/rhashtable.h:1065 [inline] __rhashtable_remove_fast include/linux/rhashtable.h:1146 [inline] rhashtable_remove_fast include/linux/rhashtable.h:1175 [inline] rhtab_delete_elem+0x404/0x1b30 kernel/bpf/hashtab.c:2954 rhtab_map_delete_elem+0xe2/0x190 kernel/bpf/hashtab.c:2985 bpf_prog_a4f1e23443ac9f8e+0x4e/0x56 bpf_dispatcher_nop_func include/linux/bpf.h:1435 [inline] __bpf_prog_run include/linux/filter.h:755 [inline] bpf_prog_run include/linux/filter.h:762 [inline] bpf_prog_run_array include/linux/bpf.h:2587 [inline] trace_call_bpf+0x3f0/0xb80 kernel/trace/bpf_trace.c:147 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:11398 do_perf_trace_lock include/trace/events/lock.h:49 [inline] perf_trace_lock+0x32d/0x410 include/trace/events/lock.h:49 __do_trace_lock_release include/trace/events/lock.h:68 [inline] trace_lock_release include/trace/events/lock.h:68 [inline] lock_release+0x38e/0x3c0 kernel/locking/lockdep.c:5879 rht_assign_unlock include/linux/rhashtable.h:431 [inline] __rhashtable_insert_fast include/linux/rhashtable.h:850 [inline] rhashtable_lookup_insert_fast include/linux/rhashtable.h:967 [inline] tipc_sk_insert net/tipc/socket.c:3027 [inline] tipc_sk_create+0xbec/0x26a0 net/tipc/socket.c:503 __sock_create+0x4b3/0x9d0 net/socket.c:1651 sock_create net/socket.c:1709 [inline] __sys_socketpair+0x1c4/0x560 net/socket.c:1856 __do_sys_socketpair net/socket.c:1909 [inline] __se_sys_socketpair net/socket.c:1906 [inline] __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1906 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd18fd9e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd190ca6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffffda RBX: 00007fd190026090 RCX: 00007fd18fd9e0d9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000001e RBP: 00007fd18fe35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000280 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd190026128 R14: 00007fd190026090 R15: 00007ffcf0e7fe28