[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   18.850166] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   24.945939] random: sshd: uninitialized urandom read (32 bytes read)
[   25.308778] random: sshd: uninitialized urandom read (32 bytes read)
[   26.181391] random: sshd: uninitialized urandom read (32 bytes read)
[   26.336555] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.10.25' (ECDSA) to the list of known hosts.
[   31.838792] random: sshd: uninitialized urandom read (32 bytes read)
executing program
[   31.935365] ==================================================================
[   31.942819] BUG: KASAN: use-after-free in _copy_to_user+0xe9/0x110
[   31.949121] Read of size 924 at addr ffff8801a77ffff2 by task syz-executor374/4525
[   31.956805] 
[   31.958426] CPU: 1 PID: 4525 Comm: syz-executor374 Not tainted 4.18.0-rc3+ #4
[   31.965682] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   31.975025] Call Trace:
[   31.977609]  dump_stack+0x1c9/0x2b4
[   31.981234]  ? dump_stack_print_info.cold.2+0x52/0x52
[   31.986415]  ? printk+0xa7/0xcf
[   31.989705]  ? kmsg_dump_rewind_nolock+0xe4/0xe4
[   31.994445]  ? _copy_to_user+0xe9/0x110
[   31.998400]  print_address_description+0x6c/0x20b
[   32.003224]  ? _copy_to_user+0xe9/0x110
[   32.007183]  kasan_report.cold.7+0x242/0x2fe
[   32.011575]  check_memory_region+0x13e/0x1b0
[   32.015967]  kasan_check_read+0x11/0x20
[   32.019930]  _copy_to_user+0xe9/0x110
[   32.023717]  bpf_test_finish.isra.7+0xee/0x1f0
[   32.028278]  ? bpf_test_init.isra.8+0x100/0x100
[   32.032935]  ? bpf_test_run+0x2fc/0x3b0
[   32.036897]  bpf_prog_test_run_skb+0x7d7/0xa30
[   32.041472]  ? bpf_test_finish.isra.7+0x1f0/0x1f0
[   32.046298]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[   32.051827]  ? __bpf_prog_get+0x9b/0x290
[   32.055873]  ? bpf_test_finish.isra.7+0x1f0/0x1f0
[   32.060707]  bpf_prog_test_run+0x130/0x1a0
[   32.064945]  __x64_sys_bpf+0x3d8/0x510
[   32.068817]  ? bpf_prog_get+0x20/0x20
[   32.072613]  ? do_syscall_64+0x9a/0x820
[   32.076578]  do_syscall_64+0x1b9/0x820
[   32.080449]  ? syscall_slow_exit_work+0x500/0x500
[   32.085285]  ? syscall_return_slowpath+0x5e0/0x5e0
[   32.090197]  ? syscall_return_slowpath+0x31d/0x5e0
[   32.095111]  ? entry_SYSCALL_64_after_hwframe+0x59/0xbe
[   32.100459]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   32.105288]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   32.110458] RIP: 0033:0x440269
[   32.113643] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 
[   32.132819] RSP: 002b:00007ffce91f3a18 EFLAGS: 00000213 ORIG_RAX: 0000000000000141
[   32.140514] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440269
[   32.147766] RDX: 0000000000000028 RSI: 0000000020000380 RDI: 000000000000000a
[   32.155022] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
[   32.162291] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401af0
[   32.169546] R13: 0000000000401b80 R14: 0000000000000000 R15: 0000000000000000
[   32.176806] 
[   32.178412] The buggy address belongs to the page:
[   32.183327] page:ffffea00069dffc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[   32.191448] flags: 0x2fffc0000000000()
[   32.195332] raw: 02fffc0000000000 ffffea00069dffc8 ffffea00069dffc8 0000000000000000
[   32.203197] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[   32.211069] page dumped because: kasan: bad access detected
[   32.216754] 
[   32.218356] Memory state around the buggy address:
[   32.223264]  ffff8801a77ffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   32.230614]  ffff8801a77fff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   32.237955] >ffff8801a77fff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   32.245290]                                                              ^
[   32.252281]  ffff8801a7800000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   32.259620]  ffff8801a7800080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   32.266965] ==================================================================
[   32.274310] Disabling lock debugging due to kernel taint
[   32.279786] Kernel panic - not syncing: panic_on_warn set ...
[   32.279786] 
[   32.287325] CPU: 1 PID: 4525 Comm: syz-executor374 Tainted: G    B             4.18.0-rc3+ #4
[   32.295965] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   32.305294] Call Trace:
[   32.307872]  dump_stack+0x1c9/0x2b4
[   32.311478]  ? dump_stack_print_info.cold.2+0x52/0x52
[   32.316651]  ? trace_hardirqs_on_thunk+0x1a/0x1c
[   32.321390]  panic+0x238/0x4e7
[   32.324568]  ? add_taint.cold.5+0x16/0x16
[   32.328699]  ? do_raw_spin_unlock+0xa7/0x2f0
[   32.333096]  ? do_raw_spin_unlock+0xa7/0x2f0
[   32.337486]  ? _copy_to_user+0xe9/0x110
[   32.341441]  kasan_end_report+0x47/0x4f
[   32.345414]  kasan_report.cold.7+0x76/0x2fe
[   32.349717]  check_memory_region+0x13e/0x1b0
[   32.354117]  kasan_check_read+0x11/0x20
[   32.358079]  _copy_to_user+0xe9/0x110
[   32.361877]  bpf_test_finish.isra.7+0xee/0x1f0
[   32.366445]  ? bpf_test_init.isra.8+0x100/0x100
[   32.371099]  ? bpf_test_run+0x2fc/0x3b0
[   32.375057]  bpf_prog_test_run_skb+0x7d7/0xa30
[   32.379621]  ? bpf_test_finish.isra.7+0x1f0/0x1f0
[   32.384444]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
[   32.389961]  ? __bpf_prog_get+0x9b/0x290
[   32.394015]  ? bpf_test_finish.isra.7+0x1f0/0x1f0
[   32.398844]  bpf_prog_test_run+0x130/0x1a0
[   32.403058]  __x64_sys_bpf+0x3d8/0x510
[   32.406923]  ? bpf_prog_get+0x20/0x20
[   32.410706]  ? do_syscall_64+0x9a/0x820
[   32.414686]  do_syscall_64+0x1b9/0x820
[   32.418553]  ? syscall_slow_exit_work+0x500/0x500
[   32.423377]  ? syscall_return_slowpath+0x5e0/0x5e0
[   32.428288]  ? syscall_return_slowpath+0x31d/0x5e0
[   32.433199]  ? entry_SYSCALL_64_after_hwframe+0x59/0xbe
[   32.438548]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   32.443374]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   32.448543] RIP: 0033:0x440269
[   32.451709] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 
[   32.470827] RSP: 002b:00007ffce91f3a18 EFLAGS: 00000213 ORIG_RAX: 0000000000000141
[   32.478531] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440269
[   32.485780] RDX: 0000000000000028 RSI: 0000000020000380 RDI: 000000000000000a
[   32.493037] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
[   32.500294] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401af0
[   32.507542] R13: 0000000000401b80 R14: 0000000000000000 R15: 0000000000000000
[   32.515251] Dumping ftrace buffer:
[   32.518776]    (ftrace buffer empty)
[   32.522474] Kernel Offset: disabled
[   32.526078] Rebooting in 86400 seconds..