[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.59' (ECDSA) to the list of known hosts. syzkaller login: [ 57.276490][ T6815] IPVS: ftp: loaded support on port[0] = 21 [ 57.278930][ T6812] IPVS: ftp: loaded support on port[0] = 21 [ 57.290623][ T6810] IPVS: ftp: loaded support on port[0] = 21 [ 57.297850][ T6811] IPVS: ftp: loaded support on port[0] = 21 [ 57.304264][ T6813] IPVS: ftp: loaded support on port[0] = 21 [ 57.310898][ T6814] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 70.958085][ T9779] ================================================================== [ 70.966464][ T9779] BUG: KASAN: use-after-free in free_netdev+0x41f/0x4a0 [ 70.973383][ T9779] Read of size 8 at addr ffff888091ec46f8 by task syz-executor405/9779 [ 70.981626][ T9779] [ 70.983986][ T9779] CPU: 0 PID: 9779 Comm: syz-executor405 Not tainted 5.7.0-syzkaller #0 [ 70.992300][ T9779] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 71.002352][ T9779] Call Trace: [ 71.005649][ T9779] dump_stack+0x188/0x20d [ 71.009961][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.014529][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.019106][ T9779] print_address_description.constprop.0.cold+0xd3/0x413 [ 71.026113][ T9779] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 71.032092][ T9779] ? vprintk_func+0x97/0x1a6 [ 71.036665][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.041259][ T9779] kasan_report.cold+0x1f/0x37 [ 71.046022][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.050594][ T9779] free_netdev+0x41f/0x4a0 [ 71.054998][ T9779] netdev_run_todo+0x5fc/0x760 [ 71.059748][ T9779] ? register_netdev+0x50/0x50 [ 71.064518][ T9779] ? rtnl_fdb_get+0xf60/0xf60 [ 71.069179][ T9779] rtnetlink_rcv_msg+0x45b/0xad0 [ 71.074101][ T9779] ? rtnl_bridge_getlink+0x870/0x870 [ 71.079382][ T9779] ? lock_acquire+0x1f2/0x8f0 [ 71.084064][ T9779] ? netlink_deliver_tap+0x146/0xb50 [ 71.089351][ T9779] netlink_rcv_skb+0x15a/0x410 [ 71.094132][ T9779] ? rtnl_bridge_getlink+0x870/0x870 [ 71.099427][ T9779] ? netlink_ack+0xa10/0xa10 [ 71.104017][ T9779] netlink_unicast+0x537/0x740 [ 71.108792][ T9779] ? netlink_attachskb+0x810/0x810 [ 71.113896][ T9779] ? _copy_from_iter_full+0x25c/0x870 [ 71.119263][ T9779] ? __phys_addr_symbol+0x2c/0x70 [ 71.124331][ T9779] ? __check_object_size+0x171/0x437 [ 71.129603][ T9779] netlink_sendmsg+0x882/0xe10 [ 71.134363][ T9779] ? aa_af_perm+0x260/0x260 [ 71.138862][ T9779] ? netlink_unicast+0x740/0x740 [ 71.143814][ T9779] ? netlink_unicast+0x740/0x740 [ 71.148891][ T9779] sock_sendmsg+0xcf/0x120 [ 71.153323][ T9779] ____sys_sendmsg+0x6e6/0x810 [ 71.158075][ T9779] ? kernel_sendmsg+0x50/0x50 [ 71.162787][ T9779] ___sys_sendmsg+0x100/0x170 [ 71.167475][ T9779] ? debug_smp_processor_id+0x2f/0x185 [ 71.173057][ T9779] ? sendmsg_copy_msghdr+0x70/0x70 [ 71.178272][ T9779] ? __fget_files+0x32f/0x500 [ 71.182951][ T9779] ? __fget_files+0x32f/0x500 [ 71.187713][ T9779] ? ksys_dup3+0x3c0/0x3c0 [ 71.192286][ T9779] ? __fget_light+0x1ab/0x270 [ 71.196958][ T9779] ? __fget_light+0x20e/0x270 [ 71.201650][ T9779] __sys_sendmsg+0xe5/0x1b0 [ 71.206159][ T9779] ? __sys_sendmsg_sock+0xb0/0xb0 [ 71.211171][ T9779] ? __x64_sys_futex+0x380/0x4f0 [ 71.216118][ T9779] ? do_syscall_64+0x21/0x7d0 [ 71.220793][ T9779] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 71.226781][ T9779] do_syscall_64+0xf6/0x7d0 [ 71.231268][ T9779] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 71.237225][ T9779] RIP: 0033:0x448629 [ 71.241114][ T9779] Code: e8 7c e6 ff ff 48 83 c4 18 c3 0f 1f 80 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 0f 83 1b 05 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 71.260713][ T9779] RSP: 002b:00007f28fe8fdce8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 71.269218][ T9779] RAX: ffffffffffffffda RBX: 00000000006dec78 RCX: 0000000000448629 [ 71.277189][ T9779] RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005 [ 71.285153][ T9779] RBP: 00000000006dec70 R08: 0000000000000000 R09: 0000000000000000 [ 71.293109][ T9779] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec7c [ 71.301068][ T9779] R13: 00007fffdf5f1bff R14: 00007f28fe8fe9c0 R15: 0000000000000001 [ 71.309056][ T9779] [ 71.311369][ T9779] Allocated by task 9746: [ 71.315682][ T9779] save_stack+0x1b/0x40 [ 71.319833][ T9779] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 71.325480][ T9779] __kmalloc+0x161/0x7a0 [ 71.329740][ T9779] sk_prot_alloc+0x223/0x2f0 [ 71.334311][ T9779] sk_alloc+0x36/0x1100 [ 71.338559][ T9779] tun_chr_open+0x7b/0x550 [ 71.342957][ T9779] misc_open+0x372/0x4a0 [ 71.347187][ T9779] chrdev_open+0x219/0x5c0 [ 71.351601][ T9779] do_dentry_open+0x546/0x1340 [ 71.356351][ T9779] path_openat+0x1e59/0x27d0 [ 71.360923][ T9779] do_filp_open+0x192/0x260 [ 71.365407][ T9779] do_sys_openat2+0x585/0x7d0 [ 71.370165][ T9779] do_sys_open+0xc3/0x140 [ 71.374489][ T9779] do_syscall_64+0xf6/0x7d0 [ 71.378988][ T9779] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 71.384873][ T9779] [ 71.387193][ T9779] Freed by task 9745: [ 71.391154][ T9779] save_stack+0x1b/0x40 [ 71.395305][ T9779] __kasan_slab_free+0xf7/0x140 [ 71.400133][ T9779] kfree+0x109/0x2b0 [ 71.404007][ T9779] __sk_destruct+0x5ad/0x7c0 [ 71.408590][ T9779] sk_destruct+0xc6/0x100 [ 71.412899][ T9779] __sk_free+0xef/0x3d0 [ 71.417048][ T9779] sk_free+0x78/0xa0 [ 71.420939][ T9779] __tun_detach+0xbc3/0x1110 [ 71.425515][ T9779] tun_chr_close+0x10e/0x180 [ 71.430086][ T9779] __fput+0x33e/0x880 [ 71.434045][ T9779] task_work_run+0xf4/0x1b0 [ 71.438527][ T9779] exit_to_usermode_loop+0x2fa/0x360 [ 71.443823][ T9779] do_syscall_64+0x6b1/0x7d0 [ 71.448424][ T9779] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 71.454285][ T9779] [ 71.456610][ T9779] The buggy address belongs to the object at ffff888091ec4000 [ 71.456610][ T9779] which belongs to the cache kmalloc-4k of size 4096 [ 71.470675][ T9779] The buggy address is located 1784 bytes inside of [ 71.470675][ T9779] 4096-byte region [ffff888091ec4000, ffff888091ec5000) [ 71.484214][ T9779] The buggy address belongs to the page: [ 71.489837][ T9779] page:ffffea000247b100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea000247b100 order:1 compound_mapcount:0 [ 71.503350][ T9779] flags: 0xfffe0000010200(slab|head) [ 71.508705][ T9779] raw: 00fffe0000010200 ffffea0002a4be88 ffffea0002a04988 ffff8880aa002000 [ 71.517282][ T9779] raw: 0000000000000000 ffff888091ec4000 0000000100000001 0000000000000000 [ 71.525840][ T9779] page dumped because: kasan: bad access detected [ 71.532411][ T9779] [ 71.534774][ T9779] Memory state around the buggy address: [ 71.540393][ T9779] ffff888091ec4580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.548537][ T9779] ffff888091ec4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb executing program [ 71.556592][ T9779] >ffff888091ec4680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.564743][ T9779] ^ [ 71.572721][ T9779] ffff888091ec4700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.580772][ T9779] ffff888091ec4780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.588833][ T9779] ================================================================== [ 71.596889][ T9779] Disabling lock debugging due to kernel taint [ 71.636256][ T9779] Kernel panic - not syncing: panic_on_warn set ... [ 71.642893][ T9779] CPU: 0 PID: 9779 Comm: syz-executor405 Tainted: G B 5.7.0-syzkaller #0 [ 71.652596][ T9779] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 71.662667][ T9779] Call Trace: [ 71.665973][ T9779] dump_stack+0x188/0x20d [ 71.670292][ T9779] ? free_netdev+0x370/0x4a0 [ 71.674870][ T9779] panic+0x2e3/0x75c [ 71.678763][ T9779] ? add_taint.cold+0x16/0x16 [ 71.683424][ T9779] ? preempt_schedule_common+0x5e/0xc0 [ 71.688861][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.693444][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.698046][ T9779] ? preempt_schedule_thunk+0x16/0x18 [ 71.703415][ T9779] ? trace_hardirqs_on+0x55/0x230 [ 71.708440][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.713021][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.717599][ T9779] end_report+0x4d/0x53 [ 71.721735][ T9779] kasan_report.cold+0xd/0x37 [ 71.726407][ T9779] ? free_netdev+0x41f/0x4a0 [ 71.730975][ T9779] free_netdev+0x41f/0x4a0 [ 71.735376][ T9779] netdev_run_todo+0x5fc/0x760 [ 71.740311][ T9779] ? register_netdev+0x50/0x50 [ 71.745078][ T9779] ? rtnl_fdb_get+0xf60/0xf60 [ 71.749751][ T9779] rtnetlink_rcv_msg+0x45b/0xad0 [ 71.754701][ T9779] ? rtnl_bridge_getlink+0x870/0x870 [ 71.760092][ T9779] ? lock_acquire+0x1f2/0x8f0 [ 71.764767][ T9779] ? netlink_deliver_tap+0x146/0xb50 [ 71.770051][ T9779] netlink_rcv_skb+0x15a/0x410 [ 71.774802][ T9779] ? rtnl_bridge_getlink+0x870/0x870 [ 71.780080][ T9779] ? netlink_ack+0xa10/0xa10 [ 71.784671][ T9779] netlink_unicast+0x537/0x740 [ 71.789449][ T9779] ? netlink_attachskb+0x810/0x810 [ 71.794556][ T9779] ? _copy_from_iter_full+0x25c/0x870 [ 71.799929][ T9779] ? __phys_addr_symbol+0x2c/0x70 [ 71.804938][ T9779] ? __check_object_size+0x171/0x437 [ 71.810218][ T9779] netlink_sendmsg+0x882/0xe10 [ 71.814972][ T9779] ? aa_af_perm+0x260/0x260 [ 71.819471][ T9779] ? netlink_unicast+0x740/0x740 [ 71.824396][ T9779] ? netlink_unicast+0x740/0x740 [ 71.829339][ T9779] sock_sendmsg+0xcf/0x120 [ 71.836169][ T9779] ____sys_sendmsg+0x6e6/0x810 [ 71.840919][ T9779] ? kernel_sendmsg+0x50/0x50 [ 71.845587][ T9779] ___sys_sendmsg+0x100/0x170 [ 71.850263][ T9779] ? debug_smp_processor_id+0x2f/0x185 [ 71.855701][ T9779] ? sendmsg_copy_msghdr+0x70/0x70 [ 71.860808][ T9779] ? __fget_files+0x32f/0x500 [ 71.865486][ T9779] ? __fget_files+0x32f/0x500 [ 71.870143][ T9779] ? ksys_dup3+0x3c0/0x3c0 [ 71.874538][ T9779] ? __fget_light+0x1ab/0x270 [ 71.879191][ T9779] ? __fget_light+0x20e/0x270 [ 71.883974][ T9779] __sys_sendmsg+0xe5/0x1b0 [ 71.888456][ T9779] ? __sys_sendmsg_sock+0xb0/0xb0 [ 71.893479][ T9779] ? __x64_sys_futex+0x380/0x4f0 [ 71.898422][ T9779] ? do_syscall_64+0x21/0x7d0 [ 71.903090][ T9779] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 71.909072][ T9779] do_syscall_64+0xf6/0x7d0 [ 71.913588][ T9779] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 71.919483][ T9779] RIP: 0033:0x448629 [ 71.923359][ T9779] Code: e8 7c e6 ff ff 48 83 c4 18 c3 0f 1f 80 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 0f 83 1b 05 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 71.942965][ T9779] RSP: 002b:00007f28fe8fdce8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 71.951357][ T9779] RAX: ffffffffffffffda RBX: 00000000006dec78 RCX: 0000000000448629 [ 71.959498][ T9779] RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005 [ 71.967470][ T9779] RBP: 00000000006dec70 R08: 0000000000000000 R09: 0000000000000000 [ 71.975623][ T9779] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec7c [ 71.983597][ T9779] R13: 00007fffdf5f1bff R14: 00007f28fe8fe9c0 R15: 0000000000000001 [ 71.992878][ T9779] Kernel Offset: disabled [ 71.997209][ T9779] Rebooting in 86400 seconds..