[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.311720] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 14.326876] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.680959] random: sshd: uninitialized urandom read (32 bytes read) [ 15.510300] random: sshd: uninitialized urandom read (32 bytes read) [ 19.783564] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.0' (ECDSA) to the list of known hosts. [ 25.179277] random: sshd: uninitialized urandom read (32 bytes read) 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 [ 25.275695] IPVS: Creating netns size=2536 id=1 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 [ 25.353603] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 25.364716] 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 [ 25.404722] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 25.415841] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 25.455841] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 25.467014] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 25.478726] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready RTNETLINK answers: Operation not supported [ 25.500746] 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" [ 25.956342] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 25.979793] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 25.986105] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 25.992958] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready executing program executing program [ 26.168135] protocol 0000 is buggy, dev sit0 [ 26.172888] ================================================================== [ 26.180284] BUG: KASAN: use-after-free in copy_to_iter+0x239/0x10e0 [ 26.186675] Read of size 12 at addr ffff8801d8264300 by task syz-executor148/4151 [ 26.194265] [ 26.195876] CPU: 0 PID: 4151 Comm: syz-executor148 Not tainted 4.9.101-gaef17a5 #29 [ 26.198779] protocol 0000 is buggy, dev sit0 [ 26.208013] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 executing program [ 26.217337] ffff8801d6c975f8[ 26.219003] protocol 0000 is buggy, dev sit0 [ 26.224613] ffffffff81eb1009 ffffea0007609900 ffff8801d8264300 [ 26.231015] 0000000000000000 ffff8801d8264300 ffff8801d8264300 ffff8801d6c97630 [ 26.239020] ffffffff8156541b[ 26.239439] protocol 0000 is buggy, dev sit0 [ 26.246306] ffff8801d8264300 000000000000000c 0000000000000000 Call Trace: [ 26.253991] [] dump_stack+0xc1/0x128 [ 26.259330] [] print_address_description+0x6c/0x234 executing program [ 26.259682] protocol 0000 is buggy, dev sit0 [ 26.270357] [] kasan_report.cold.6+0x242/0x2fe [ 26.276570] [] ? copy_to_iter+0x239/0x10e0 [ 26.280130] protocol 0000 is buggy, dev sit0 [ 26.287432] [] check_memory_region+0x14f/0x1b0 [ 26.293641] [] kasan_check_read+0x11/0x20 [ 26.299438] [] copy_to_iter+0x239/0x10e0 [ 26.300366] protocol 0000 is buggy, dev sit0 [ 26.309928] [] ? iov_iter_get_pages+0xd60/0xd60 executing program executing program [ 26.316225] [] ? check_preemption_disabled+0x3b/0x170 [ 26.320781] protocol 0000 is buggy, dev sit0 [ 26.327413] [] skb_copy_datagram_iter+0x1d1/0x8f0 [ 26.333881] [] ? sock_has_perm+0x1c2/0x3e0 [ 26.339743] [] packet_recvmsg+0x263/0xf40 [ 26.340970] protocol 0000 is buggy, dev sit0 [ 26.349899] [] ? packet_rcv_has_room+0xa0/0xa0 [ 26.356114] [] ? avc_has_perm_noaudit+0x450/0x450 [ 26.361346] protocol 0000 is buggy, dev sit0 executing program [ 26.366955] [] ? selinux_socket_recvmsg+0x3f/0x50 [ 26.373426] [] ? security_socket_recvmsg+0x97/0xc0 [ 26.379978] [] ? packet_rcv_has_room+0xa0/0xa0 [ 26.386184] [] sock_recvmsg+0xc6/0x110 [ 26.391694] [] sock_read_iter+0x24a/0x360 [ 26.397463] [] ? inode_has_perm.isra.32+0x111/0x160 [ 26.404097] [] ? sock_recvmsg+0x110/0x110 [ 26.409874] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 executing program [ 26.418350] [] do_iter_readv_writev+0x301/0x4b0 [ 26.424646] [] ? vfs_iter_write+0x460/0x460 [ 26.430587] [] ? rw_verify_area+0xe5/0x2b0 [ 26.436440] [] do_readv_writev+0x2f6/0x7a0 [ 26.442293] [] ? vfs_write+0x530/0x530 [ 26.447807] [] ? SYSC_sendto+0x24b/0x370 [ 26.453492] [] ? __fget+0x20a/0x3b0 [ 26.458742] [] ? __fget+0x231/0x3b0 [ 26.463990] [] ? __fget+0x47/0x3b0 executing program [ 26.469154] [] vfs_readv+0x84/0xc0 [ 26.474320] [] do_readv+0xe6/0x260 [ 26.479479] [] ? vfs_readv+0xc0/0xc0 [ 26.484815] [] SyS_readv+0x27/0x30 [ 26.489975] [] ? rw_copy_check_uvector+0x330/0x330 [ 26.496524] [] do_syscall_64+0x1a6/0x490 [ 26.502207] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.509103] [ 26.510720] Allocated by task 4152: [ 26.514317] save_stack_trace+0x16/0x20 executing program executing program [ 26.518264] save_stack+0x43/0xd0 [ 26.521687] kasan_kmalloc+0xc7/0xe0 [ 26.525371] kasan_slab_alloc+0x12/0x20 [ 26.529314] __kmalloc_track_caller+0xdc/0x2b0 [ 26.533866] __kmalloc_reserve.isra.37+0x33/0xc0 [ 26.538597] __alloc_skb+0x11a/0x600 [ 26.542282] alloc_skb_with_frags+0xaf/0x520 [ 26.546660] sock_alloc_send_pskb+0x5a9/0x750 [ 26.551126] packet_sendmsg+0x1581/0x4470 [ 26.555245] sock_sendmsg+0xcc/0x110 [ 26.558932] SYSC_sendto+0x21c/0x370 [ 26.562616] SyS_sendto+0x40/0x50 [ 26.566038] do_syscall_64+0x1a6/0x490 [ 26.569895] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.574963] [ 26.576565] Freed by task 4152: [ 26.579814] save_stack_trace+0x16/0x20 [ 26.583757] save_stack+0x43/0xd0 [ 26.587176] kasan_slab_free+0x72/0xc0 [ 26.591031] kfree+0xfb/0x310 [ 26.594106] skb_free_head+0x8b/0xb0 [ 26.597874] skb_release_data+0x329/0x400 [ 26.601991] skb_release_all+0x4a/0x60 [ 26.605847] __kfree_skb+0x15/0x20 [ 26.609356] kfree_skb+0xcc/0x340 [ 26.612787] sit_tunnel_xmit+0xfb/0x2590 [ 26.616825] dev_hard_start_xmit+0x197/0x8b0 [ 26.621201] __dev_queue_xmit+0x19a5/0x2080 [ 26.625504] dev_queue_xmit+0x17/0x20 [ 26.629283] packet_sendmsg+0x1eff/0x4470 [ 26.633417] sock_sendmsg+0xcc/0x110 [ 26.637103] SYSC_sendto+0x21c/0x370 [ 26.640790] SyS_sendto+0x40/0x50 [ 26.644221] do_syscall_64+0x1a6/0x490 [ 26.648079] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.653150] [ 26.654752] The buggy address belongs to the object at ffff8801d8264280 [ 26.654752] which belongs to the cache kmalloc-512 of size 512 [ 26.667375] The buggy address is located 128 bytes inside of [ 26.667375] 512-byte region [ffff8801d8264280, ffff8801d8264480) [ 26.679237] The buggy address belongs to the page: [ 26.684144] page:ffffea0007609900 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 26.694323] flags: 0x8000000000004080(slab|head) [ 26.699047] page dumped because: kasan: bad access detected [ 26.704725] [ 26.706330] Memory state around the buggy address: [ 26.711230] ffff8801d8264200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program executing program executing program executing program [ 26.718568] ffff8801d8264280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.725897] >ffff8801d8264300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.733228] ^ [ 26.736567] ffff8801d8264380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.743894] ffff8801d8264400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.751219] ================================================================== [ 26.758557] Disabling lock debugging due to kernel taint executing program [ 26.765770] Kernel panic - not syncing: panic_on_warn set ... [ 26.765770] [ 26.773120] CPU: 0 PID: 4151 Comm: syz-executor148 Tainted: G B 4.9.101-gaef17a5 #29 [ 26.782100] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.791429] ffff8801d6c97558 ffffffff81eb1009 ffffffff843c50e5 00000000ffffffff [ 26.799408] 0000000000000000 0000000000000000 ffff8801d8264300 ffff8801d6c97618 [ 26.807400] ffffffff8141f925 0000000041b58ab3 ffffffff843b87e8 ffffffff8141f766 [ 26.815387] Call Trace: executing program executing program [ 26.817955] [] dump_stack+0xc1/0x128 [ 26.823293] [] panic+0x1bf/0x3bc [ 26.828286] [] ? add_taint.cold.6+0x16/0x16 [ 26.834231] [] ? ___preempt_schedule+0x16/0x18 [ 26.840446] [] kasan_end_report+0x47/0x4f [ 26.846213] [] kasan_report.cold.6+0x76/0x2fe [ 26.852336] [] ? copy_to_iter+0x239/0x10e0 [ 26.858221] [] check_memory_region+0x14f/0x1b0 [ 26.864434] [] kasan_check_read+0x11/0x20 executing program [ 26.870216] [] copy_to_iter+0x239/0x10e0 [ 26.875904] [] ? iov_iter_get_pages+0xd60/0xd60 [ 26.882208] [] ? check_preemption_disabled+0x3b/0x170 [ 26.889122] [] skb_copy_datagram_iter+0x1d1/0x8f0 [ 26.895586] [] ? sock_has_perm+0x1c2/0x3e0 [ 26.901442] [] packet_recvmsg+0x263/0xf40 [ 26.907234] [] ? packet_rcv_has_room+0xa0/0xa0 [ 26.913437] [] ? avc_has_perm_noaudit+0x450/0x450 executing program [ 26.919901] [] ? selinux_socket_recvmsg+0x3f/0x50 [ 26.926365] [] ? security_socket_recvmsg+0x97/0xc0 [ 26.932915] [] ? packet_rcv_has_room+0xa0/0xa0 [ 26.939119] [] sock_recvmsg+0xc6/0x110 [ 26.944634] [] sock_read_iter+0x24a/0x360 [ 26.950411] [] ? inode_has_perm.isra.32+0x111/0x160 [ 26.957055] [] ? sock_recvmsg+0x110/0x110 [ 26.962823] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 executing program [ 26.971287] [] do_iter_readv_writev+0x301/0x4b0 [ 26.977578] [] ? vfs_iter_write+0x460/0x460 [ 26.983526] [] ? rw_verify_area+0xe5/0x2b0 [ 26.989379] [] do_readv_writev+0x2f6/0x7a0 [ 26.995236] [] ? vfs_write+0x530/0x530 [ 27.000759] [] ? SYSC_sendto+0x24b/0x370 [ 27.006445] [] ? __fget+0x20a/0x3b0 [ 27.011708] [] ? __fget+0x231/0x3b0 executing program [ 27.016954] [] ? __fget+0x47/0x3b0 [ 27.022115] [] vfs_readv+0x84/0xc0 [ 27.027275] [] do_readv+0xe6/0x260 [ 27.032434] [] ? vfs_readv+0xc0/0xc0 [ 27.037768] [] SyS_readv+0x27/0x30 [ 27.042935] [] ? rw_copy_check_uvector+0x330/0x330 [ 27.049487] [] do_syscall_64+0x1a6/0x490 [ 27.055170] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.062481] Dumping ftrace buffer: [ 27.065989] (ftrace buffer empty) [ 27.069677] Kernel Offset: disabled [ 27.073279] Rebooting in 86400 seconds..