=============================== [ INFO: suspicious RCU usage. ] 4.4.174+ #4 Not tainted ------------------------------- net/ipv6/ip6_fib.c:1465 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 5 locks held by syz-executor.3/8998: #0: (&pipe->mutex/1){+.+.+.}, at: [] pipe_lock_nested fs/pipe.c:65 [inline] #0: (&pipe->mutex/1){+.+.+.}, at: [] pipe_lock fs/pipe.c:73 [inline] #0: (&pipe->mutex/1){+.+.+.}, at: [] pipe_wait+0x1b8/0x1e0 fs/pipe.c:121 #1: (((&net->ipv6.ip6_fib_timer))){+.-...}, at: [] lockdep_copy_map include/linux/lockdep.h:165 [inline] #1: (((&net->ipv6.ip6_fib_timer))){+.-...}, at: [] call_timer_fn+0xde/0x850 kernel/time/timer.c:1175 #2: (fib6_gc_lock){+.-...}, at: [] spin_lock_bh include/linux/spinlock.h:307 [inline] #2: (fib6_gc_lock){+.-...}, at: [] fib6_run_gc+0x3a/0x230 net/ipv6/ip6_fib.c:1811 #3: (rcu_read_lock[ 236.496657] SELinux: ebitmap: map size 0 does not match my size 64 (high bit was -570425344) ){......}, at: [] __fib6_clean_all+0x0/0x240 net/ipv6/ip6_fib.c:1698 #4: (&tb->tb6_lock){++--..}, at: [] __fib6_clean_all+0xe8/0x240 net/ipv6/ip6_fib.c:1712 stack backtrace: CPU: 1 PID: 8998 Comm: syz-executor.3 Not tainted 4.4.174+ #4 0000000000000000 f00e4ae07920428b ffff8801db707940 ffffffff81aad1a1 ffff8800ba5e9500 0000000000000000 0000000000000001 00000000000005b9 ffff8800a6d8c740 ffff8801db707970 ffffffff813ab7d6 ffff8801db707b90 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [] lockdep_rcu_suspicious.cold+0x10a/0x149 kernel/locking/lockdep.c:4305 [] fib6_del+0x7ea/0xae0 net/ipv6/ip6_fib.c:1465 [] fib6_clean_node+0x29c/0x500 net/ipv6/ip6_fib.c:1652 [] fib6_walk_continue+0x3e0/0x630 net/ipv6/ip6_fib.c:1578 [] fib6_walk+0x91/0xe0 net/ipv6/ip6_fib.c:1623 [] fib6_clean_tree+0xe8/0x120 net/ipv6/ip6_fib.c:1697 [] __fib6_clean_all+0x100/0x240 net/ipv6/ip6_fib.c:1713 [] fib6_clean_all net/ipv6/ip6_fib.c:1724 [inline] [] fib6_run_gc+0xaf/0x230 net/ipv6/ip6_fib.c:1821 [] fib6_gc_timer_cb+0x1d/0x30 net/ipv6/ip6_fib.c:1836 [] call_timer_fn+0x18d/0x850 kernel/time/timer.c:1185 [] __run_timers kernel/time/timer.c:1261 [inline] [] run_timer_softirq+0x51f/0xb70 kernel/time/timer.c:1444 [] __do_softirq+0x226/0xa3f kernel/softirq.c:273 [] invoke_softirq kernel/softirq.c:350 [inline] [] irq_exit+0x10a/0x150 kernel/softirq.c:391 [] exiting_irq arch/x86/include/asm/apic.h:652 [inline] [] smp_apic_timer_interrupt+0x7e/0xb0 arch/x86/kernel/apic/apic.c:926 [] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:768 [] ? copy_user_enhanced_fast_string+0x7/0x10 arch/x86/lib/copy_user_64.S:221 [] pipe_write+0x262/0xe70 fs/pipe.c:421 [] new_sync_write fs/read_write.c:480 [inline] [] __vfs_write+0x2e8/0x3d0 fs/read_write.c:493 [] vfs_write+0x182/0x4e0 fs/read_write.c:540 [] SYSC_write fs/read_write.c:587 [inline] [] SyS_write+0xdc/0x1c0 fs/read_write.c:579 [] entry_SYSCALL_64_fastpath+0x1e/0x9a syz-executor.0 (9011) used greatest stack depth: 23352 bytes left uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 uinput: invalid abs[00] min:255 max:0 netlink: 64 bytes leftover after parsing attributes in process `syz-executor.1'.