[ OK ] Started OpenBSD Secure Shell server. [ 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 '10.128.0.98' (ECDSA) to the list of known hosts. 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 syzkaller login: [ 47.898272][ T7257] ================================================================== [ 47.906499][ T7257] BUG: KASAN: slab-out-of-bounds in fl6_update_dst+0x159/0x1a0 [ 47.914042][ T7257] Read of size 16 at addr ffff88809ea15768 by task syz-executor822/7257 [ 47.922358][ T7257] [ 47.924696][ T7257] CPU: 1 PID: 7257 Comm: syz-executor822 Not tainted 5.7.0-rc6-syzkaller #0 [ 47.933364][ T7257] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.943423][ T7257] Call Trace: [ 47.946719][ T7257] dump_stack+0x1e9/0x30e [ 47.951055][ T7257] print_address_description+0x74/0x5c0 [ 47.956603][ T7257] ? vprintk_emit+0x342/0x3c0 [ 47.961286][ T7257] ? printk+0x62/0x83 [ 47.965295][ T7257] ? trace_irq_disable_rcuidle+0x1f/0x1d0 [ 47.971052][ T7257] __kasan_report+0x103/0x1a0 [ 47.975746][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 47.980620][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 47.985481][ T7257] kasan_report+0x4d/0x80 [ 47.989817][ T7257] ? check_memory_region+0x2b5/0x2f0 [ 47.995108][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 47.999964][ T7257] ? memcpy+0x25/0x60 [ 48.003951][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 48.008806][ T7257] ? udpv6_sendmsg+0x1ce7/0x3200 [ 48.013749][ T7257] ? ip_skb_dst_mtu+0x500/0x500 [ 48.018627][ T7257] ? smack_socket_sendmsg+0x345/0x450 [ 48.024010][ T7257] ? tomoyo_socket_sendmsg_permission+0x24a/0x320 [ 48.030433][ T7257] ? sock_rps_record_flow+0x1c/0x370 [ 48.035736][ T7257] ? inet6_ioctl+0x160/0x160 [ 48.040332][ T7257] ? __sys_sendto+0x3f3/0x590 [ 48.045029][ T7257] ? rcu_read_lock_sched_held+0x106/0x170 [ 48.050934][ T7257] ? check_preemption_disabled+0xb0/0x240 [ 48.056743][ T7257] ? debug_smp_processor_id+0x5/0x20 [ 48.062035][ T7257] ? __x64_sys_sendto+0xda/0xf0 [ 48.067068][ T7257] ? do_syscall_64+0xf3/0x1b0 [ 48.071757][ T7257] ? entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 48.077826][ T7257] [ 48.080276][ T7257] Allocated by task 7251: [ 48.084610][ T7257] __kasan_kmalloc+0x114/0x160 [ 48.089374][ T7257] __kmalloc+0x24b/0x330 [ 48.093623][ T7257] sock_kmalloc+0x98/0x100 [ 48.098039][ T7257] ipv6_renew_options+0x27c/0xa70 [ 48.103075][ T7257] do_ipv6_setsockopt+0x244d/0x3a20 [ 48.108288][ T7257] ipv6_setsockopt+0x49/0x160 [ 48.112967][ T7257] __sys_setsockopt+0x564/0x710 [ 48.117830][ T7257] __x64_sys_setsockopt+0xb1/0xc0 [ 48.122869][ T7257] do_syscall_64+0xf3/0x1b0 [ 48.127383][ T7257] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 48.133292][ T7257] [ 48.135607][ T7257] Freed by task 5070: [ 48.139590][ T7257] __kasan_slab_free+0x125/0x190 [ 48.144528][ T7257] kfree+0x10a/0x220 [ 48.148460][ T7257] kernfs_fop_release+0x1d8/0x2b0 [ 48.153481][ T7257] __fput+0x2ed/0x750 [ 48.157500][ T7257] task_work_run+0x147/0x1d0 [ 48.162094][ T7257] prepare_exit_to_usermode+0x48e/0x600 [ 48.167645][ T7257] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 48.173537][ T7257] [ 48.175908][ T7257] The buggy address belongs to the object at ffff88809ea15700 [ 48.175908][ T7257] which belongs to the cache kmalloc-128 of size 128 [ 48.189962][ T7257] The buggy address is located 104 bytes inside of [ 48.189962][ T7257] 128-byte region [ffff88809ea15700, ffff88809ea15780) [ 48.203407][ T7257] The buggy address belongs to the page: [ 48.209135][ T7257] page:ffffea00027a8540 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 48.218472][ T7257] flags: 0xfffe0000000200(slab) [ 48.223356][ T7257] raw: 00fffe0000000200 ffffea0002936308 ffffea0002a06f88 ffff8880aa400700 [ 48.232134][ T7257] raw: 0000000000000000 ffff88809ea15000 0000000100000010 0000000000000000 [ 48.240717][ T7257] page dumped because: kasan: bad access detected [ 48.247141][ T7257] 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 [ 48.249471][ T7257] Memory state around the buggy address: [ 48.255275][ T7257] ffff88809ea15600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 48.264061][ T7257] ffff88809ea15680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 48.272207][ T7257] >ffff88809ea15700: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc [ 48.280284][ T7257] ^ [ 48.287758][ T7257] ffff88809ea15780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program executing program executing program executing program executing program [ 48.296067][ T7257] ffff88809ea15800: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc [ 48.304291][ T7257] ================================================================== [ 48.312383][ T7257] Disabling lock debugging due to kernel taint [ 48.325962][ T7257] Kernel panic - not syncing: panic_on_warn set ... [ 48.332580][ T7257] CPU: 1 PID: 7257 Comm: syz-executor822 Tainted: G B 5.7.0-rc6-syzkaller #0 executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 48.342639][ T7257] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.352692][ T7257] Call Trace: [ 48.356136][ T7257] dump_stack+0x1e9/0x30e [ 48.360459][ T7257] panic+0x264/0x7a0 [ 48.364452][ T7257] ? trace_hardirqs_on+0x30/0x70 [ 48.369415][ T7257] __kasan_report+0x191/0x1a0 [ 48.374137][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 48.378990][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 48.383872][ T7257] kasan_report+0x4d/0x80 [ 48.388203][ T7257] ? check_memory_region+0x2b5/0x2f0 [ 48.393485][ T7257] ? fl6_update_dst+0x159/0x1a0 executing program executing program executing program executing program executing program executing program [ 48.398344][ T7257] ? memcpy+0x25/0x60 [ 48.402329][ T7257] ? fl6_update_dst+0x159/0x1a0 [ 48.407447][ T7257] ? udpv6_sendmsg+0x1ce7/0x3200 [ 48.412384][ T7257] ? ip_skb_dst_mtu+0x500/0x500 [ 48.417260][ T7257] ? smack_socket_sendmsg+0x345/0x450 [ 48.422640][ T7257] ? tomoyo_socket_sendmsg_permission+0x24a/0x320 [ 48.429055][ T7257] ? sock_rps_record_flow+0x1c/0x370 [ 48.434340][ T7257] ? inet6_ioctl+0x160/0x160 [ 48.438925][ T7257] ? __sys_sendto+0x3f3/0x590 [ 48.443608][ T7257] ? rcu_read_lock_sched_held+0x106/0x170 [ 48.449857][ T7257] ? check_preemption_disabled+0xb0/0x240 [ 48.455747][ T7257] ? debug_smp_processor_id+0x5/0x20 [ 48.461050][ T7257] ? __x64_sys_sendto+0xda/0xf0 [ 48.465882][ T7257] ? do_syscall_64+0xf3/0x1b0 [ 48.470551][ T7257] ? entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 48.478066][ T7257] Kernel Offset: disabled [ 48.482403][ T7257] Rebooting in 86400 seconds..