[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.69' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 54.834944][ T6519] ------------[ cut here ]------------ [ 54.840416][ T6519] refcount_t: addition on 0; use-after-free. [ 54.847066][ T6519] WARNING: CPU: 1 PID: 6519 at lib/refcount.c:25 refcount_warn_saturate+0x13d/0x1a0 [ 54.856557][ T6519] Modules linked in: [ 54.860452][ T6519] CPU: 1 PID: 6519 Comm: syz-executor570 Not tainted 5.15.0-rc6-syzkaller #0 [ 54.869354][ T6519] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.879537][ T6519] RIP: 0010:refcount_warn_saturate+0x13d/0x1a0 [ 54.885812][ T6519] Code: c7 80 e1 b3 8a 31 c0 e8 31 8e 3b fd 0f 0b eb a3 e8 b8 79 71 fd c6 05 43 86 b6 09 01 48 c7 c7 e0 e1 b3 8a 31 c0 e8 13 8e 3b fd <0f> 0b eb 85 e8 9a 79 71 fd c6 05 26 86 b6 09 01 48 c7 c7 40 e2 b3 [ 54.905519][ T6519] RSP: 0018:ffffc900014dfed0 EFLAGS: 00010246 [ 54.911623][ T6519] RAX: f1edd9615e736100 RBX: 0000000000000002 RCX: ffff88801a6f1c80 [ 54.919693][ T6519] RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 [ 54.927759][ T6519] RBP: 0000000000000002 R08: ffffffff81695fe2 R09: ffffed10173a57a8 [ 54.935856][ T6519] R10: ffffed10173a57a8 R11: 0000000000000000 R12: ffff8880258c9900 [ 54.943926][ T6519] R13: ffff888071dbedc0 R14: 0000000000000003 R15: dffffc0000000000 [ 54.951923][ T6519] FS: 0000555556b16300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 [ 54.960942][ T6519] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 54.967656][ T6519] CR2: 00007f0a2b914330 CR3: 0000000073408000 CR4: 00000000003506e0 [ 54.976027][ T6519] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 54.984096][ T6519] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 54.992283][ T6519] Call Trace: [ 54.995579][ T6519] __se_sys_memfd_secret+0x2ea/0x350 [ 55.000962][ T6519] do_syscall_64+0x44/0xd0 [ 55.005460][ T6519] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 55.011356][ T6519] RIP: 0033:0x7f0a2b902f89 [ 55.015959][ T6519] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 55.035666][ T6519] RSP: 002b:00007fff8e742228 EFLAGS: 00000246 ORIG_RAX: 00000000000001bf [ 55.044185][ T6519] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0a2b902f89 [ 55.052291][ T6519] RDX: 00007f0a2b8c5e93 RSI: 0000000000000012 RDI: 0000000000080000 [ 55.060271][ T6519] RBP: 00007f0a2b8c6f70 R08: 0000000000000000 R09: 0000000000000000 [ 55.068335][ T6519] R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f0a2b8c7000 [ 55.076381][ T6519] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 55.084474][ T6519] Kernel panic - not syncing: panic_on_warn set ... [ 55.091098][ T6519] CPU: 1 PID: 6519 Comm: syz-executor570 Not tainted 5.15.0-rc6-syzkaller #0 [ 55.099863][ T6519] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 55.109989][ T6519] Call Trace: [ 55.113268][ T6519] dump_stack_lvl+0x1dc/0x2d8 [ 55.117929][ T6519] ? show_regs_print_info+0x12/0x12 [ 55.123107][ T6519] ? log_buf_vmcoreinfo_setup+0x498/0x498 [ 55.128813][ T6519] panic+0x2d6/0x810 [ 55.132690][ T6519] ? __warn+0x13e/0x270 [ 55.136828][ T6519] ? nmi_panic+0x90/0x90 [ 55.141059][ T6519] __warn+0x26a/0x270 [ 55.145104][ T6519] ? refcount_warn_saturate+0x13d/0x1a0 [ 55.150631][ T6519] ? refcount_warn_saturate+0x13d/0x1a0 [ 55.156154][ T6519] report_bug+0x1b1/0x2e0 [ 55.160466][ T6519] handle_bug+0x3d/0x70 [ 55.164600][ T6519] exc_invalid_op+0x16/0x40 [ 55.169080][ T6519] asm_exc_invalid_op+0x12/0x20 [ 55.173908][ T6519] RIP: 0010:refcount_warn_saturate+0x13d/0x1a0 [ 55.180038][ T6519] Code: c7 80 e1 b3 8a 31 c0 e8 31 8e 3b fd 0f 0b eb a3 e8 b8 79 71 fd c6 05 43 86 b6 09 01 48 c7 c7 e0 e1 b3 8a 31 c0 e8 13 8e 3b fd <0f> 0b eb 85 e8 9a 79 71 fd c6 05 26 86 b6 09 01 48 c7 c7 40 e2 b3 [ 55.199710][ T6519] RSP: 0018:ffffc900014dfed0 EFLAGS: 00010246 [ 55.205842][ T6519] RAX: f1edd9615e736100 RBX: 0000000000000002 RCX: ffff88801a6f1c80 [ 55.213797][ T6519] RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 [ 55.221771][ T6519] RBP: 0000000000000002 R08: ffffffff81695fe2 R09: ffffed10173a57a8 [ 55.229766][ T6519] R10: ffffed10173a57a8 R11: 0000000000000000 R12: ffff8880258c9900 [ 55.237726][ T6519] R13: ffff888071dbedc0 R14: 0000000000000003 R15: dffffc0000000000 [ 55.245694][ T6519] ? wake_up_klogd+0xb2/0xf0 [ 55.250274][ T6519] __se_sys_memfd_secret+0x2ea/0x350 [ 55.255558][ T6519] do_syscall_64+0x44/0xd0 [ 55.259960][ T6519] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 55.265844][ T6519] RIP: 0033:0x7f0a2b902f89 [ 55.270252][ T6519] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 55.289844][ T6519] RSP: 002b:00007fff8e742228 EFLAGS: 00000246 ORIG_RAX: 00000000000001bf [ 55.298239][ T6519] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0a2b902f89 [ 55.306191][ T6519] RDX: 00007f0a2b8c5e93 RSI: 0000000000000012 RDI: 0000000000080000 [ 55.314155][ T6519] RBP: 00007f0a2b8c6f70 R08: 0000000000000000 R09: 0000000000000000 [ 55.322122][ T6519] R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f0a2b8c7000 [ 55.330104][ T6519] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 55.338335][ T6519] Kernel Offset: disabled [ 55.342796][ T6519] Rebooting in 86400 seconds..