[   21.628010] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available)
[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[   21.717260] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available)
[?25h[?0c.
[   22.110061] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available)

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   23.049496] random: sshd: uninitialized urandom read (32 bytes read, 98 bits of entropy available)
[   24.481566] random: sshd: uninitialized urandom read (32 bytes read, 104 bits of entropy available)
Warning: Permanently added '10.128.10.3' (ECDSA) to the list of known hosts.
[   29.890477] random: sshd: uninitialized urandom read (32 bytes read, 110 bits of entropy available)
executing program
[   29.984735] 
[   29.986375] ======================================================
[   29.992660] [ INFO: possible circular locking dependency detected ]
[   29.999030] 4.4.120-gd63fdf6 #28 Not tainted
[   30.003404] -------------------------------------------------------
[   30.009811] syzkaller221042/3785 is trying to acquire lock:
[   30.015500]  (&mm->mmap_sem){++++++}, at: [<ffffffff81495684>] __might_fault+0xe4/0x1d0
[   30.024128] 
[   30.024128] but task is already holding lock:
[   30.030066]  (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_ioctl+0x367/0xfa0
[   30.038562] 
[   30.038562] which lock already depends on the new lock.
[   30.038562] 
[   30.046842] 
[   30.046842] the existing dependency chain (in reverse order) is:
[   30.054427] 
-> #1 (ashmem_mutex){+.+.+.}:
[   30.059183]        [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460
[   30.065425]        [<ffffffff8376a39b>] mutex_lock_nested+0xbb/0x850
[   30.072002]        [<ffffffff82c61463>] ashmem_mmap+0x53/0x400
[   30.078062]        [<ffffffff814b0e4f>] mmap_region+0x94f/0x1250
[   30.084289]        [<ffffffff814b1c4d>] do_mmap+0x4fd/0x9d0
[   30.090105]        [<ffffffff814700ce>] vm_mmap_pgoff+0x16e/0x1c0
[   30.096422]        [<ffffffff814afe1f>] SyS_mmap_pgoff+0x33f/0x560
[   30.102821]        [<ffffffff8101beb6>] SyS_mmap+0x16/0x20
[   30.108534]        [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98
[   30.115717] 
-> #0 (&mm->mmap_sem){++++++}:
[   30.120546]        [<ffffffff8123ab2f>] __lock_acquire+0x371f/0x4b50
[   30.127117]        [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460
[   30.133350]        [<ffffffff814956ea>] __might_fault+0x14a/0x1d0
[   30.139687]        [<ffffffff82c628f4>] ashmem_ioctl+0x3b4/0xfa0
[   30.145918]        [<ffffffff81559daa>] do_vfs_ioctl+0x7aa/0xee0
[   30.152144]        [<ffffffff8155a56f>] SyS_ioctl+0x8f/0xc0
[   30.157935]        [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98
[   30.165116] 
[   30.165116] other info that might help us debug this:
[   30.165116] 
[   30.173231]  Possible unsafe locking scenario:
[   30.173231] 
[   30.179254]        CPU0                    CPU1
[   30.183884]        ----                    ----
[   30.188515]   lock(ashmem_mutex);
[   30.192161]                                lock(&mm->mmap_sem);
[   30.198417]                                lock(ashmem_mutex);
[   30.204578]   lock(&mm->mmap_sem);
[   30.208399] 
[   30.208399]  *** DEADLOCK ***
[   30.208399] 
[   30.214427] 1 lock held by syzkaller221042/3785:
[   30.219155]  #0:  (ashmem_mutex){+.+.+.}, at: [<ffffffff82c628a7>] ashmem_ioctl+0x367/0xfa0
[   30.228192] 
[   30.228192] stack backtrace:
[   30.232654] CPU: 1 PID: 3785 Comm: syzkaller221042 Not tainted 4.4.120-gd63fdf6 #28
[   30.240420] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   30.249746]  0000000000000000 2b4b7b174cad59c5 ffff8801d91bf9b8 ffffffff81d0408d
[   30.257718]  ffffffff851a0010 ffffffff851a0010 ffffffff851bda40 ffff8800bbb5a0f8
[   30.265690]  ffff8800bbb59800 ffff8801d91bfa00 ffffffff81233ba1 ffff8800bbb5a0f8
[   30.273671] Call Trace:
[   30.276241]  [<ffffffff81d0408d>] dump_stack+0xc1/0x124
[   30.281588]  [<ffffffff81233ba1>] print_circular_bug+0x271/0x310
[   30.287702]  [<ffffffff8123ab2f>] __lock_acquire+0x371f/0x4b50
[   30.293639]  [<ffffffff81237410>] ? debug_check_no_locks_freed+0x2c0/0x2c0
[   30.300618]  [<ffffffff812367ff>] ? mark_held_locks+0xaf/0x100
[   30.306559]  [<ffffffff81230151>] ? __lock_is_held+0xa1/0xf0
[   30.312326]  [<ffffffff8123d7ce>] lock_acquire+0x15e/0x460
[   30.317921]  [<ffffffff81495684>] ? __might_fault+0xe4/0x1d0
[   30.323684]  [<ffffffff814956ea>] __might_fault+0x14a/0x1d0
[   30.329359]  [<ffffffff81495684>] ? __might_fault+0xe4/0x1d0
[   30.335125]  [<ffffffff82c628f4>] ashmem_ioctl+0x3b4/0xfa0
[   30.340714]  [<ffffffff814b08f9>] ? mmap_region+0x3f9/0x1250
[   30.346481]  [<ffffffff82c62540>] ? ashmem_shrink_scan+0x390/0x390
[   30.352768]  [<ffffffff814700e0>] ? vm_mmap_pgoff+0x180/0x1c0
[   30.358623]  [<ffffffff82c62540>] ? ashmem_shrink_scan+0x390/0x390
[   30.364913]  [<ffffffff81559daa>] do_vfs_ioctl+0x7aa/0xee0
[   30.370504]  [<ffffffff81559600>] ? ioctl_preallocate+0x1f0/0x1f0
[   30.376701]  [<ffffffff815232a0>] ? fput+0x20/0x150
[   30.381685]  [<ffffffff814afbb8>] ? SyS_mmap_pgoff+0x