[ 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 '10.128.10.6' (ECDSA) to the list of known hosts. 2020/04/29 13:23:25 fuzzer started syzkaller login: [ 55.297037][ T7027] as (7027) used greatest stack depth: 23088 bytes left 2020/04/29 13:23:27 connecting to host at 10.128.0.26:35981 2020/04/29 13:23:27 checking machine... 2020/04/29 13:23:27 checking revisions... 2020/04/29 13:23:27 testing simple program... [ 55.974462][ T7038] IPVS: ftp: loaded support on port[0] = 21 2020/04/29 13:23:27 building call list... [ 56.311880][ T2742] tipc: TX() has been purged, node left! [ 57.825025][ T7033] can: request_module (can-proto-0) failed. executing program [ 59.405025][ T7033] can: request_module (can-proto-0) failed. [ 59.417272][ T7033] can: request_module (can-proto-0) failed. [ 59.892215][ T7033] ================================================================== [ 59.900399][ T7033] BUG: KASAN: null-ptr-deref in x25_disconnect+0x253/0x370 [ 59.907573][ T7033] Write of size 4 at addr 00000000000000d8 by task syz-fuzzer/7033 [ 59.915954][ T7033] [ 59.918280][ T7033] CPU: 1 PID: 7033 Comm: syz-fuzzer Not tainted 5.7.0-rc2-syzkaller #0 [ 59.926487][ T7033] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.936515][ T7033] Call Trace: [ 59.939798][ T7033] dump_stack+0x188/0x20d [ 59.944124][ T7033] ? x25_disconnect+0x253/0x370 [ 59.948970][ T7033] ? __sock_release+0x280/0x280 [ 59.953795][ T7033] __kasan_report.cold+0x5/0x4d [ 59.958636][ T7033] ? rcu_read_lock_held+0x1/0xb0 [ 59.963548][ T7033] ? x25_disconnect+0x253/0x370 [ 59.968393][ T7033] ? x25_disconnect+0x253/0x370 [ 59.973226][ T7033] kasan_report+0x33/0x50 [ 59.977528][ T7033] check_memory_region+0x141/0x190 [ 59.982613][ T7033] x25_disconnect+0x253/0x370 [ 59.987274][ T7033] x25_release+0x345/0x420 [ 59.991678][ T7033] __sock_release+0xcd/0x280 [ 59.996251][ T7033] sock_close+0x18/0x20 [ 60.000381][ T7033] __fput+0x33e/0x880 [ 60.004352][ T7033] task_work_run+0xf4/0x1b0 [ 60.008833][ T7033] exit_to_usermode_loop+0x2fa/0x360 [ 60.014110][ T7033] do_syscall_64+0x6b1/0x7d0 [ 60.018739][ T7033] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 60.024620][ T7033] RIP: 0033:0x4afb40 [ 60.028494][ T7033] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 60.048086][ T7033] RSP: 002b:000000c0000774f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000003 [ 60.056473][ T7033] RAX: 0000000000000000 RBX: 000000c00002e500 RCX: 00000000004afb40 [ 60.064430][ T7033] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 [ 60.072394][ T7033] RBP: 000000c000077538 R08: 0000000000000000 R09: 0000000000000000 [ 60.080338][ T7033] R10: 0000000000000000 R11: 0000000000000216 R12: ffffffffffffffff [ 60.088284][ T7033] R13: 0000000000000163 R14: 0000000000000162 R15: 0000000000000200 [ 60.096252][ T7033] ================================================================== [ 60.104295][ T7033] Disabling lock debugging due to kernel taint [ 60.111263][ T7033] Kernel panic - not syncing: panic_on_warn set ... [ 60.117849][ T7033] CPU: 1 PID: 7033 Comm: syz-fuzzer Tainted: G B 5.7.0-rc2-syzkaller #0 [ 60.127647][ T7033] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.137685][ T7033] Call Trace: [ 60.140959][ T7033] dump_stack+0x188/0x20d [ 60.145274][ T7033] ? __sock_release+0x280/0x280 [ 60.150102][ T7033] panic+0x2e3/0x75c [ 60.153968][ T7033] ? add_taint.cold+0x16/0x16 [ 60.158738][ T7033] ? x25_disconnect+0x253/0x370 [ 60.163560][ T7033] ? trace_hardirqs_on+0x55/0x220 [ 60.168557][ T7033] ? x25_disconnect+0x253/0x370 [ 60.173390][ T7033] ? __sock_release+0x280/0x280 [ 60.178211][ T7033] end_report+0x4d/0x53 [ 60.182339][ T7033] __kasan_report.cold+0xd/0x4d [ 60.187171][ T7033] ? rcu_read_lock_held+0x1/0xb0 [ 60.192078][ T7033] ? x25_disconnect+0x253/0x370 [ 60.196899][ T7033] ? x25_disconnect+0x253/0x370 [ 60.201730][ T7033] kasan_report+0x33/0x50 [ 60.206029][ T7033] check_memory_region+0x141/0x190 [ 60.211112][ T7033] x25_disconnect+0x253/0x370 [ 60.216193][ T7033] x25_release+0x345/0x420 [ 60.220590][ T7033] __sock_release+0xcd/0x280 [ 60.225152][ T7033] sock_close+0x18/0x20 [ 60.229290][ T7033] __fput+0x33e/0x880 [ 60.233257][ T7033] task_work_run+0xf4/0x1b0 [ 60.237821][ T7033] exit_to_usermode_loop+0x2fa/0x360 [ 60.243077][ T7033] do_syscall_64+0x6b1/0x7d0 [ 60.247652][ T7033] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 60.253513][ T7033] RIP: 0033:0x4afb40 [ 60.257661][ T7033] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 60.277240][ T7033] RSP: 002b:000000c0000774f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000003 [ 60.285618][ T7033] RAX: 0000000000000000 RBX: 000000c00002e500 RCX: 00000000004afb40 [ 60.293559][ T7033] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 [ 60.301559][ T7033] RBP: 000000c000077538 R08: 0000000000000000 R09: 0000000000000000 [ 60.309572][ T7033] R10: 0000000000000000 R11: 0000000000000216 R12: ffffffffffffffff [ 60.317539][ T7033] R13: 0000000000000163 R14: 0000000000000162 R15: 0000000000000200 [ 60.326870][ T7033] Kernel Offset: disabled [ 60.331204][ T7033] Rebooting in 86400 seconds..