random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)

======================================================
[ INFO: possible circular locking dependency detected ]
4.9.103-g7fd4075 #36 Not tainted
-------------------------------------------------------
syz-executor670/3804 is trying to acquire lock:
 (rtnl_mutex){+.+.+.}, at: [<ffffffff830b4867>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
but task is already holding lock:
 (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff833453f9>] lock_sock include/net/sock.h:1404 [inline]
 (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff833453f9>] do_ip_setsockopt.isra.13+0x269/0x2b10 net/ipv4/ip_sockglue.c:638
which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

       lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
       lock_sock_nested+0xc6/0x120 net/core/sock.c:2511
       lock_sock include/net/sock.h:1404 [inline]
       do_ip_getsockopt+0x167/0x1600 net/ipv4/ip_sockglue.c:1319
       ip_getsockopt+0x91/0x180 net/ipv4/ip_sockglue.c:1547
       udp_getsockopt+0x4a/0x80 net/ipv4/udp.c:2163
       sock_common_getsockopt+0x9a/0xe0 net/core/sock.c:2665
       SYSC_getsockopt net/socket.c:1803 [inline]
       SyS_getsockopt+0x150/0x240 net/socket.c:1785
       do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
       entry_SYSCALL_64_after_swapgs+0x5d/0xdb

       check_prev_add kernel/locking/lockdep.c:1828 [inline]
       check_prevs_add kernel/locking/lockdep.c:1938 [inline]
       validate_chain kernel/locking/lockdep.c:2265 [inline]
       __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345
       lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
       __mutex_lock_common kernel/locking/mutex.c:521 [inline]
       mutex_lock_nested+0xc0/0x870 kernel/locking/mutex.c:621
       rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
       mrtsock_destruct+0x3b/0x1e0 net/ipv4/ipmr.c:1231
       ip_ra_control+0x2c2/0x420 net/ipv4/ip_sockglue.c:360
       do_ip_setsockopt.isra.13+0x15ff/0x2b10 net/ipv4/ip_sockglue.c:1139
       ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1242
       raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:833
       sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706
       SYSC_setsockopt net/socket.c:1772 [inline]
       SyS_setsockopt+0x166/0x260 net/socket.c:1751
       do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
       entry_SYSCALL_64_after_swapgs+0x5d/0xdb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sk_lock-AF_INET);
                               lock(rtnl_mutex);
                               lock(sk_lock-AF_INET);
  lock(rtnl_mutex);

 *** DEADLOCK ***

1 lock held by syz-executor670/3804:
 #0:  (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff833453f9>] lock_sock include/net/sock.h:1404 [inline]
 #0:  (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff833453f9>] do_ip_setsockopt.isra.13+0x269/0x2b10 net/ipv4/ip_sockglue.c:638

stack backtrace:
CPU: 0 PID: 3804 Comm: syz-executor670 Not tainted 4.9.103-g7fd4075 #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801b5ebf5f8 ffffffff81eb34a9 ffffffff8559cf30 ffffffff855e79f0
 ffffffff8559cf30 ffff8801b7b288e8 ffff8801b7b28000 ffff8801b5ebf640
 ffffffff8142642d 0000000000000001 00000000b7b28000 0000000000000001
Call Trace:
 [<ffffffff81eb34a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb34a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8142642d>] print_circular_bug.cold.51+0x1bd/0x27d kernel/locking/lockdep.c:1202
 [<ffffffff812394e9>] check_prev_add kernel/locking/lockdep.c:1828 [inline]
 [<ffffffff812394e9>] check_prevs_add kernel/locking/lockdep.c:1938 [inline]
 [<ffffffff812394e9>] validate_chain kernel/locking/lockdep.c:2265 [inline]
 [<ffffffff812394e9>] __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345
 [<ffffffff8123afb0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff839ed2c0>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
 [<ffffffff839ed2c0>] mutex_lock_nested+0xc0/0x870 kernel/locking/mutex.c:621
 [<ffffffff830b4867>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70
 [<ffffffff8348488b>] mrtsock_destruct+0x3b/0x1e0 net/ipv4/ipmr.c:1231
 [<ffffffff83345032>] ip_ra_control+0x2c2/0x420 net/ipv4/ip_sockglue.c:360
 [<ffffffff8334678f>] do_ip_setsockopt.isra.13+0x15ff/0x2b10 net/ipv4/ip_sockglue.c:1139
 [<ffffffff83347cda>] ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1242
 [<ffffffff833e9c27>] raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:833
 [<ffffffff8301c75a>] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706
 [<ffffffff83019516>] SYSC_setsockopt net/socket.c:1772 [inline]
 [<ffffffff83019516>] SyS_setsockopt+0x166/0x260 net/socket.c:1751
 [<ffffffff83018830>] ? move_addr_to_kernel+0x5