[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.190038] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 23.808204] random: sshd: uninitialized urandom read (32 bytes read) [ 24.313178] random: sshd: uninitialized urandom read (32 bytes read) [ 24.856045] random: sshd: uninitialized urandom read (32 bytes read) [ 24.971848] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.36' (ECDSA) to the list of known hosts. [ 30.363356] random: sshd: uninitialized urandom read (32 bytes read) net.ipv6.conf.syz_tun.accept_dad = 0 net.ipv6.conf.syz_tun.router_solicitations = 0 [ 30.443604] IPVS: Creating netns size=2536 id=1 RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Error: argument "bridge0" is wrong: Device does not exist Error: argument "bridge0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist [ 30.555686] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 30.566774] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready Error: argument "team0" is wrong: Device does not exist Error: argument "team0" is wrong: Device does not exist [ 30.607119] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 30.617703] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready RTNETLINK answers: Operation not supported [ 30.656534] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 30.667450] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 30.679051] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 30.691184] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" RTNETLINK answers: Operation not supported Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" [ 31.122834] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 31.145226] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 31.151318] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 31.158319] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready executing program [ 31.336780] ================================================================== [ 31.344276] BUG: KASAN: use-after-free in __dev_queue_xmit+0x18fc/0x2080 [ 31.351087] Read of size 2 at addr ffff8801c7affc42 by task syz-executor200/3730 [ 31.358591] [ 31.360197] CPU: 1 PID: 3730 Comm: syz-executor200 Not tainted 4.9.97-g1321d42 #13 [ 31.367883] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.377214] ffff8801be8ef500 ffffffff81eb0b69 ffffea00071ebf80 ffff8801c7affc42 [ 31.385198] 0000000000000000 ffff8801c7affc42 ffff8801d7d7c850 ffff8801be8ef538 [ 31.393184] ffffffff8156540b ffff8801c7affc42 0000000000000002 0000000000000000 [ 31.401189] Call Trace: [ 31.403754] [] dump_stack+0xc1/0x128 [ 31.409092] [] print_address_description+0x6c/0x234 [ 31.415729] [] kasan_report.cold.6+0x242/0x2fe [ 31.421938] [] ? __dev_queue_xmit+0x18fc/0x2080 [ 31.428232] [] __asan_report_load2_noabort+0x14/0x20 [ 31.434959] [] __dev_queue_xmit+0x18fc/0x2080 [ 31.441076] [] ? __dev_queue_xmit+0x1e2/0x2080 [ 31.447277] [] ? netdev_pick_tx+0x2c0/0x2c0 [ 31.453222] [] ? __cap_capable+0x168/0x1c0 [ 31.459078] [] ? selinux_capable+0x36/0x40 [ 31.464933] [] ? security_capable+0x94/0xc0 [ 31.470876] [] dev_queue_xmit+0x17/0x20 [ 31.476475] [] packet_sendmsg+0x1eff/0x4470 [ 31.482420] [] ? debug_check_no_locks_freed+0x210/0x210 [ 31.489404] [] ? packet_cached_dev_get+0x1f0/0x1f0 [ 31.495954] [] ? sock_has_perm+0x292/0x3e0 [ 31.501809] [] ? sock_has_perm+0x9f/0x3e0 [ 31.507577] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 31.514648] [] ? selinux_socket_sendmsg+0x3f/0x50 [ 31.521122] [] ? security_socket_sendmsg+0x8f/0xc0 [ 31.527671] [] ? packet_cached_dev_get+0x1f0/0x1f0 [ 31.534221] [] sock_sendmsg+0xcc/0x110 [ 31.539726] [] ___sys_sendmsg+0x47a/0x840 [ 31.545497] [] ? get_page_from_freelist+0xcb6/0x1a00 [ 31.552220] [] ? copy_msghdr_from_user+0x560/0x560 [ 31.558771] [] ? debug_check_no_locks_freed+0x210/0x210 [ 31.565753] [] ? __activate_page+0x790/0x790 [ 31.571782] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 31.578678] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.585487] [] __sys_sendmmsg+0x161/0x3d0 [ 31.591255] [] ? SyS_sendmsg+0x50/0x50 [ 31.596764] [] ? handle_mm_fault+0x6a4/0x28e0 [ 31.602882] [] ? selinux_netlbl_sock_rcv_skb+0x480/0x480 [ 31.609949] [] ? packet_bind+0x13f/0x190 [ 31.615631] [] ? vm_insert_mixed+0x200/0x200 [ 31.621659] [] ? up_read+0x1a/0x40 [ 31.626824] [] ? __do_page_fault+0x183/0xd50 [ 31.632853] [] SyS_sendmmsg+0x35/0x60 [ 31.638272] [] ? __sys_sendmmsg+0x3d0/0x3d0 [ 31.644214] [] do_syscall_64+0x1a6/0x490 [ 31.649896] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 31.656792] [ 31.658391] Allocated by task 3730: [ 31.661990] save_stack_trace+0x16/0x20 [ 31.665934] save_stack+0x43/0xd0 [ 31.669356] kasan_kmalloc+0xc7/0xe0 [ 31.673040] kasan_slab_alloc+0x12/0x20 [ 31.676985] __kmalloc_track_caller+0xdc/0x2b0 [ 31.681537] __kmalloc_reserve.isra.37+0x33/0xc0 [ 31.686262] __alloc_skb+0x11a/0x600 [ 31.689944] alloc_skb_with_frags+0xaf/0x520 [ 31.694321] sock_alloc_send_pskb+0x5a9/0x750 [ 31.698785] packet_sendmsg+0x1581/0x4470 [ 31.702904] sock_sendmsg+0xcc/0x110 [ 31.706588] ___sys_sendmsg+0x47a/0x840 [ 31.710531] __sys_sendmmsg+0x161/0x3d0 [ 31.714474] SyS_sendmmsg+0x35/0x60 [ 31.718070] do_syscall_64+0x1a6/0x490 [ 31.721928] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 31.726997] [ 31.728594] Freed by task 3730: [ 31.731845] save_stack_trace+0x16/0x20 [ 31.735789] save_stack+0x43/0xd0 [ 31.739212] kasan_slab_free+0x72/0xc0 [ 31.743069] kfree+0xfb/0x310 [ 31.746145] skb_free_head+0x8b/0xb0 [ 31.749828] skb_release_data+0x329/0x400 [ 31.753943] skb_release_all+0x4a/0x60 [ 31.757801] __kfree_skb+0x15/0x20 [ 31.761308] kfree_skb+0xcc/0x340 [ 31.764734] __skb_complete_tx_timestamp+0x2ba/0x3a0 [ 31.769809] __skb_tstamp_tx+0x19a/0x4b0 [ 31.773838] __dev_queue_xmit+0x130f/0x2080 [ 31.778127] dev_queue_xmit+0x17/0x20 [ 31.781902] packet_sendmsg+0x1eff/0x4470 [ 31.786021] sock_sendmsg+0xcc/0x110 [ 31.789705] ___sys_sendmsg+0x47a/0x840 [ 31.793651] __sys_sendmmsg+0x161/0x3d0 [ 31.797595] SyS_sendmmsg+0x35/0x60 [ 31.801202] do_syscall_64+0x1a6/0x490 [ 31.805061] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 31.810130] [ 31.811730] The buggy address belongs to the object at ffff8801c7affb80 [ 31.811730] which belongs to the cache kmalloc-512 of size 512 [ 31.824355] The buggy address is located 194 bytes inside of [ 31.824355] 512-byte region [ffff8801c7affb80, ffff8801c7affd80) [ 31.836196] The buggy address belongs to the page: [ 31.841096] page:ffffea00071ebf80 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 31.851268] flags: 0x8000000000004080(slab|head) [ 31.855990] page dumped because: kasan: bad access detected [ 31.861666] [ 31.863264] Memory state around the buggy address: [ 31.868173] ffff8801c7affb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.875512] ffff8801c7affb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.882839] >ffff8801c7affc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.890166] ^ [ 31.895586] ffff8801c7affc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.902915] ffff8801c7affd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.910241] ================================================================== [ 31.917568] Disabling lock debugging due to kernel taint [ 31.923031] Kernel panic - not syncing: panic_on_warn set ... [ 31.923031] [ 31.930365] CPU: 1 PID: 3730 Comm: syz-executor200 Tainted: G B 4.9.97-g1321d42 #13 [ 31.939260] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.948591] ffff8801be8ef460 ffffffff81eb0b69 ffffffff843c4d05 00000000ffffffff [ 31.956579] 0000000000000000 0000000000000001 ffff8801d7d7c850 ffff8801be8ef520 [ 31.964561] ffffffff8141f975 0000000041b58ab3 ffffffff843b8408 ffffffff8141f7b6 [ 31.972539] Call Trace: [ 31.975102] [] dump_stack+0xc1/0x128 [ 31.980440] [] panic+0x1bf/0x3bc [ 31.985426] [] ? add_taint.cold.6+0x16/0x16 [ 31.991372] [] kasan_end_report+0x47/0x4f [ 31.997141] [] kasan_report.cold.6+0x76/0x2fe [ 32.003256] [] ? __dev_queue_xmit+0x18fc/0x2080 [ 32.009546] [] __asan_report_load2_noabort+0x14/0x20 [ 32.016267] [] __dev_queue_xmit+0x18fc/0x2080 [ 32.022381] [] ? __dev_queue_xmit+0x1e2/0x2080 [ 32.028583] [] ? netdev_pick_tx+0x2c0/0x2c0 [ 32.034526] [] ? __cap_capable+0x168/0x1c0 [ 32.040383] [] ? selinux_capable+0x36/0x40 [ 32.046238] [] ? security_capable+0x94/0xc0 [ 32.052188] [] dev_queue_xmit+0x17/0x20 [ 32.057784] [] packet_sendmsg+0x1eff/0x4470 [ 32.063728] [] ? debug_check_no_locks_freed+0x210/0x210 [ 32.070713] [] ? packet_cached_dev_get+0x1f0/0x1f0 [ 32.077261] [] ? sock_has_perm+0x292/0x3e0 [ 32.083113] [] ? sock_has_perm+0x9f/0x3e0 [ 32.088882] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 32.095952] [] ? selinux_socket_sendmsg+0x3f/0x50 [ 32.102415] [] ? security_socket_sendmsg+0x8f/0xc0 [ 32.108974] [] ? packet_cached_dev_get+0x1f0/0x1f0 [ 32.115523] [] sock_sendmsg+0xcc/0x110 [ 32.121029] [] ___sys_sendmsg+0x47a/0x840 [ 32.126797] [] ? get_page_from_freelist+0xcb6/0x1a00 [ 32.133518] [] ? copy_msghdr_from_user+0x560/0x560 [ 32.140069] [] ? debug_check_no_locks_freed+0x210/0x210 [ 32.147055] [] ? __activate_page+0x790/0x790 [ 32.153087] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 32.159983] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 32.166793] [] __sys_sendmmsg+0x161/0x3d0 [ 32.172560] [] ? SyS_sendmsg+0x50/0x50 [ 32.178068] [] ? handle_mm_fault+0x6a4/0x28e0 [ 32.184184] [] ? selinux_netlbl_sock_rcv_skb+0x480/0x480 [ 32.191253] [] ? packet_bind+0x13f/0x190 [ 32.196934] [] ? vm_insert_mixed+0x200/0x200 [ 32.202961] [] ? up_read+0x1a/0x40 [ 32.208132] [] ? __do_page_fault+0x183/0xd50 [ 32.214159] [] SyS_sendmmsg+0x35/0x60 [ 32.219579] [] ? __sys_sendmmsg+0x3d0/0x3d0 [ 32.225519] [] do_syscall_64+0x1a6/0x490 [ 32.231201] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.238485] Dumping ftrace buffer: [ 32.241996] (ftrace buffer empty) [ 32.245677] Kernel Offset: disabled [ 32.249279] Rebooting in 86400 seconds..