netlink: 'syz.0.1403': attribute type 21 has an invalid length.
=============================
WARNING: suspicious RCU usage
syzkaller #0 Not tainted
-----------------------------
kernel/events/callchain.c:163 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
locks held by syz.0.1403/10639: 1, last CPU#1:
 #0: ffffffff8ed5c8d8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
 #0: ffffffff8ed5c8d8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_read_lock_tasks_trace include/linux/rcupdate_trace.h:59 [inline]
 #0: ffffffff8ed5c8d8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_test_run_raw_tp+0x1d3/0xa60 net/bpf/test_run.c:756

stack backtrace:
CPU: 1 UID: 0 PID: 10639 Comm: syz.0.1403 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6938
 get_callchain_entry+0x2b7/0x3c0 kernel/events/callchain.c:163
 get_perf_callchain+0xd5/0x880 kernel/events/callchain.c:231
 __bpf_get_stack+0x375/0xae0 kernel/bpf/stackmap.c:826
 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1692 [inline]
 bpf_get_stack_raw_tp+0x1a4/0x210 kernel/trace/bpf_trace.c:1682
 bpf_prog_5fad78f7e5ba870f+0x43/0x4b
 bpf_dispatcher_nop_func include/linux/bpf.h:1451 [inline]
 __bpf_prog_run include/linux/filter.h:779 [inline]
 bpf_prog_run include/linux/filter.h:786 [inline]
 __bpf_prog_test_run_raw_tp+0x421/0xa60 net/bpf/test_run.c:767
 bpf_prog_test_run_raw_tp+0x579/0x840 net/bpf/test_run.c:824
 bpf_prog_test_run+0x2c5/0x340 kernel/bpf/syscall.c:4804
 __sys_bpf+0xa22/0xd90 kernel/bpf/syscall.c:6385
 __do_sys_bpf kernel/bpf/syscall.c:6486 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6483 [inline]
 __x64_sys_bpf+0xba/0xd0 kernel/bpf/syscall.c:6483
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f954639e159
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:00007f954727d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f9546625fa0 RCX: 00007f954639e159
RDX: 000000000000000c RSI: 00002000000003c0 RDI: 000000000000000a
RBP: 00007f9546435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9546626038 R14: 00007f9546625fa0 R15: 00007ffde78466b8
 </TASK>