random: crng init done audit: type=1400 audit(1561619166.875:5): avc: denied { associate } for pid=2081 comm="syz-executor.0" name="syz0" scontext=unconfined_u:object_r:unlabeled_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=filesystem permissive=1 =============================== [ INFO: suspicious RCU usage. ] 4.9.183+ #4 Not tainted ------------------------------- ./include/linux/inetdevice.h:205 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 4 locks held by syz-executor.0/2230: #0: (rcu_read_lock_bh){......}, at: [<000000004092a181>] ip_finish_output2+0x20b/0x1280 net/ipv4/ip_output.c:198 #1: (rcu_read_lock_bh){......}, at: [<000000008c12b0db>] __dev_queue_xmit+0x1d4/0x1bd0 net/core/dev.c:3407 #2: (_xmit_TUNNEL6#2){+.....}, at: [<00000000d9549502>] spin_lock include/linux/spinlock.h:302 [inline] #2: (_xmit_TUNNEL6#2){+.....}, at: [<00000000d9549502>] __netif_tx_lock include/linux/netdevice.h:3573 [inline] #2: (_xmit_TUNNEL6#2){+.....}, at: [<00000000d9549502>] __dev_queue_xmit+0x1116/0x1bd0 net/core/dev.c:3469 #3: (slock-AF_INET){+.-...}, at: [<0000000025e12bc9>] spin_trylock include/linux/spinlock.h:312 [inline] #3: (slock-AF_INET){+.-...}, at: [<0000000025e12bc9>] icmp_xmit_lock net/ipv4/icmp.c:220 [inline] #3: (slock-AF_INET){+.-...}, at: [<0000000025e12bc9>] __icmp_send+0x48b/0x1420 net/ipv4/icmp.c:656 stack backtrace: CPU: 0 PID: 2230 Comm: syz-executor.0 Not tainted 4.9.183+ #4 ffff8801caa7edd8 ffffffff81b580a1 ffff8801ced6cb40 0000000000000000 0000000000000002 00000000000000cd ffff8801caa90000 ffff8801caa7ee08 ffffffff81404fb9 ffff8801ced6cb98 ffff8801caa7ef28 ffff8801da63b300 Call Trace: [<0000000089e39d52>] __dump_stack lib/dump_stack.c:15 [inline] [<0000000089e39d52>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<0000000001c54882>] lockdep_rcu_suspicious.cold+0x10a/0x149 kernel/locking/lockdep.c:4455 [<000000008e728e73>] __in_dev_get_rcu include/linux/inetdevice.h:205 [inline] [<000000008e728e73>] fib_compute_spec_dst+0x6c4/0xcc0 net/ipv4/fib_frontend.c:284 [<00000000d8517315>] __ip_options_echo+0x4be/0x13e0 net/ipv4/ip_options.c:177 [<00000000b59a29ef>] __icmp_send+0x648/0x1420 net/ipv4/icmp.c:685 [<0000000005272bc0>] ipv4_send_dest_unreach net/ipv4/route.c:1202 [inline] [<0000000005272bc0>] ipv4_link_failure+0x460/0x850 net/ipv4/route.c:1209 [<00000000ebb44a83>] dst_link_failure include/net/dst.h:490 [inline] [<00000000ebb44a83>] vti6_xmit net/ipv6/ip6_vti.c:522 [inline] [<00000000ebb44a83>] vti6_tnl_xmit+0xb08/0x17f0 net/ipv6/ip6_vti.c:561 [<0000000011f70835>] __netdev_start_xmit include/linux/netdevice.h:4072 [inline] [<0000000011f70835>] netdev_start_xmit include/linux/netdevice.h:4081 [inline] [<0000000011f70835>] xmit_one net/core/dev.c:2977 [inline] [<0000000011f70835>] dev_hard_start_xmit+0x195/0x8b0 net/core/dev.c:2993 [<000000000a46f235>] __dev_queue_xmit+0x11a3/0x1bd0 net/core/dev.c:3473 [<000000003490737c>] dev_queue_xmit+0x18/0x20 net/core/dev.c:3506 [<000000003c8daa4b>] neigh_direct_output+0x16/0x20 net/core/neighbour.c:1366 [<000000001ddc65d3>] dst_neigh_output include/net/dst.h:470 [inline] [<000000001ddc65d3>] ip_finish_output2+0x6a2/0x1280 net/ipv4/ip_output.c:225 [<00000000d71a493b>] ip_finish_output+0x3c4/0xce0 net/ipv4/ip_output.c:313 [<0000000087bebda6>] NF_HOOK_COND include/linux/netfilter.h:246 [inline] [<0000000087bebda6>] ip_output+0x1ec/0x5b0 net/ipv4/ip_output.c:401 [<00000000ed9915bf>] dst_output include/net/dst.h:507 [inline] [<00000000ed9915bf>] NF_HOOK_THRESH include/linux/netfilter.h:232 [inline] [<00000000ed9915bf>] NF_HOOK include/linux/netfilter.h:255 [inline] [<00000000ed9915bf>] raw_send_hdrinc net/ipv4/raw.c:421 [inline] [<00000000ed9915bf>] raw_sendmsg+0x1c5c/0x23e0 net/ipv4/raw.c:643 [<0000000003a9a6a1>] inet_sendmsg+0x202/0x4d0 net/ipv4/af_inet.c:766 [<000000006c4247c8>] sock_sendmsg_nosec net/socket.c:649 [inline] [<000000006c4247c8>] sock_sendmsg+0xbe/0x110 net/socket.c:659 [<00000000694276cb>] sock_write_iter+0x235/0x3d0 net/socket.c:857 [<00000000065bbf71>] new_sync_write fs/read_write.c:498 [inline] [<00000000065bbf71>] __vfs_write+0x3c1/0x560 fs/read_write.c:511 [<000000003cb2bc8d>] vfs_write+0x185/0x520 fs/read_write.c:559 [<00000000fb8995c2>] SYSC_write fs/read_write.c:607 [inline] [<00000000fb8995c2>] SyS_write+0x121/0x270 fs/read_write.c:599