[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.44' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 72.048269][ T6523] ------------[ cut here ]------------ [ 72.054003][ T6523] refcount_t: addition on 0; use-after-free. [ 72.060342][ T6523] WARNING: CPU: 1 PID: 6523 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0 [ 72.070540][ T6523] Modules linked in: [ 72.074613][ T6523] CPU: 0 PID: 6523 Comm: syz-executor324 Not tainted 5.15.0-rc6-syzkaller #0 [ 72.084085][ T6523] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.094320][ T6523] RIP: 0010:refcount_warn_saturate+0x169/0x1e0 [ 72.100579][ T6523] Code: 09 31 ff 89 de e8 27 5e 9c fd 84 db 0f 85 36 ff ff ff e8 da 57 9c fd 48 c7 c7 40 ee e3 89 c6 05 52 67 7f 09 01 e8 52 1c 19 05 <0f> 0b e9 17 ff ff ff e8 bb 57 9c fd 0f b6 1d 37 67 7f 09 31 ff 89 [ 72.120381][ T6523] RSP: 0018:ffffc9000252ff10 EFLAGS: 00010286 [ 72.126546][ T6523] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 72.134649][ T6523] RDX: ffff888024539c80 RSI: ffffffff815e9da8 RDI: fffff520004a5fd4 [ 72.142630][ T6523] RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 [ 72.150692][ T6523] R10: ffffffff815e3b4e R11: 0000000000000000 R12: 0000000000000000 [ 72.159124][ T6523] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 72.167618][ T6523] FS: 000055555710e300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 [ 72.176686][ T6523] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 72.183283][ T6523] CR2: 00007f88ee794000 CR3: 0000000072fe0000 CR4: 00000000003506f0 [ 72.191334][ T6523] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 72.199501][ T6523] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 72.207607][ T6523] Call Trace: [ 72.210888][ T6523] __x64_sys_memfd_secret+0x182/0x1e0 [ 72.216427][ T6523] do_syscall_64+0x35/0xb0 [ 72.220880][ T6523] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 72.226831][ T6523] RIP: 0033:0x7f788efeef79 [ 72.231252][ T6523] 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 [ 72.250948][ T6523] RSP: 002b:00007fff759bc9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001bf [ 72.259585][ T6523] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f788efeef79 [ 72.259607][ T6523] RDX: 00007f788efb1e83 RSI: 0000000000000012 RDI: 0000000000000000 [ 72.259624][ T6523] RBP: 00007f788efb2f60 R08: 0000000000000000 R09: 0000000000000000 [ 72.259641][ T6523] R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f788efb2ff0 [ 72.259655][ T6523] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 72.259689][ T6523] Kernel panic - not syncing: panic_on_warn set ... [ 72.306152][ T6523] CPU: 1 PID: 6523 Comm: syz-executor324 Not tainted 5.15.0-rc6-syzkaller #0 [ 72.314904][ T6523] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.324949][ T6523] Call Trace: [ 72.328247][ T6523] dump_stack_lvl+0xcd/0x134 [ 72.332828][ T6523] panic+0x2b0/0x6dd [ 72.336712][ T6523] ? __warn_printk+0xf3/0xf3 [ 72.341303][ T6523] ? __warn.cold+0x1a/0x44 [ 72.345718][ T6523] ? refcount_warn_saturate+0x169/0x1e0 [ 72.351328][ T6523] __warn.cold+0x35/0x44 [ 72.355557][ T6523] ? wake_up_klogd.part.0+0x8e/0xd0 [ 72.360746][ T6523] ? refcount_warn_saturate+0x169/0x1e0 [ 72.366278][ T6523] report_bug+0x1bd/0x210 [ 72.370607][ T6523] handle_bug+0x3c/0x60 [ 72.374760][ T6523] exc_invalid_op+0x14/0x40 [ 72.379245][ T6523] asm_exc_invalid_op+0x12/0x20 [ 72.384097][ T6523] RIP: 0010:refcount_warn_saturate+0x169/0x1e0 [ 72.390250][ T6523] Code: 09 31 ff 89 de e8 27 5e 9c fd 84 db 0f 85 36 ff ff ff e8 da 57 9c fd 48 c7 c7 40 ee e3 89 c6 05 52 67 7f 09 01 e8 52 1c 19 05 <0f> 0b e9 17 ff ff ff e8 bb 57 9c fd 0f b6 1d 37 67 7f 09 31 ff 89 [ 72.409840][ T6523] RSP: 0018:ffffc9000252ff10 EFLAGS: 00010286 [ 72.415891][ T6523] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 72.423862][ T6523] RDX: ffff888024539c80 RSI: ffffffff815e9da8 RDI: fffff520004a5fd4 [ 72.431829][ T6523] RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 [ 72.439818][ T6523] R10: ffffffff815e3b4e R11: 0000000000000000 R12: 0000000000000000 [ 72.447951][ T6523] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 72.455912][ T6523] ? wake_up_klogd.part.0+0x8e/0xd0 [ 72.461101][ T6523] ? vprintk+0x88/0x90 [ 72.465159][ T6523] __x64_sys_memfd_secret+0x182/0x1e0 [ 72.470519][ T6523] do_syscall_64+0x35/0xb0 [ 72.474929][ T6523] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 72.480821][ T6523] RIP: 0033:0x7f788efeef79 [ 72.485237][ T6523] 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 [ 72.504826][ T6523] RSP: 002b:00007fff759bc9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001bf [ 72.513222][ T6523] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f788efeef79 [ 72.521174][ T6523] RDX: 00007f788efb1e83 RSI: 0000000000000012 RDI: 0000000000000000 [ 72.529125][ T6523] RBP: 00007f788efb2f60 R08: 0000000000000000 R09: 0000000000000000 [ 72.537077][ T6523] R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f788efb2ff0 [ 72.545030][ T6523] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 72.553185][ T6523] Kernel Offset: disabled [ 72.557570][ T6523] Rebooting in 86400 seconds..