[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 12.432656] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 13.478566] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 13.719444] random: sshd: uninitialized urandom read (32 bytes read) [ 14.753306] random: sshd: uninitialized urandom read (32 bytes read) [ 14.885643] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.16' (ECDSA) to the list of known hosts. [ 20.646947] 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 [ 20.739697] 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 [ 20.820010] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 20.831122] 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 [ 20.873105] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 20.884422] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready RTNETLINK answers: Operation not supported [ 20.925301] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 20.936350] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 20.948410] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 20.962097] 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" [ 21.425068] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 21.447650] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 21.453762] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 21.461400] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready executing program [ 21.631449] protocol 0000 is buggy, dev sit0 [ 21.636144] ================================================================== [ 21.643500] BUG: KASAN: use-after-free in copy_to_iter+0x239/0x10e0 [ 21.649876] Read of size 12 at addr ffff8801da2c8a80 by task syz-executor184/4145 [ 21.657462] [ 21.659066] CPU: 0 PID: 4145 Comm: syz-executor184 Not tainted 4.9.100-g73fdfa3 #26 [ 21.666828] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.676163] ffff8801d7a5f5f8 ffffffff81eb0f09 ffffea000768b200 ffff8801da2c8a80 [ 21.684140] 0000000000000000 ffff8801da2c8a80 ffff8801da2c8a80 ffff8801d7a5f630 [ 21.692118] ffffffff8156532b ffff8801da2c8a80 000000000000000c 0000000000000000 [ 21.700092] Call Trace: [ 21.702654] [] dump_stack+0xc1/0x128 [ 21.707996] [] print_address_description+0x6c/0x234 [ 21.714647] [] kasan_report.cold.6+0x242/0x2fe [ 21.720850] [] ? copy_to_iter+0x239/0x10e0 [ 21.726711] [] check_memory_region+0x14f/0x1b0 [ 21.732915] [] kasan_check_read+0x11/0x20 [ 21.738691] [] copy_to_iter+0x239/0x10e0 [ 21.744372] [] ? iov_iter_get_pages+0xd60/0xd60 [ 21.750659] [] ? check_preemption_disabled+0x3b/0x170 [ 21.757470] [] skb_copy_datagram_iter+0x1d1/0x8f0 [ 21.763930] [] ? sock_has_perm+0x1c2/0x3e0 [ 21.769785] [] packet_recvmsg+0x263/0xf40 [ 21.775553] [] ? packet_rcv_has_room+0xa0/0xa0 [ 21.781755] [] ? avc_has_perm_noaudit+0x450/0x450 [ 21.788223] [] ? selinux_socket_recvmsg+0x3f/0x50 [ 21.794682] [] ? security_socket_recvmsg+0x97/0xc0 [ 21.801247] [] ? packet_rcv_has_room+0xa0/0xa0 [ 21.807451] [] sock_recvmsg+0xc6/0x110 [ 21.812966] [] sock_read_iter+0x24a/0x360 [ 21.818735] [] ? inode_has_perm.isra.32+0x111/0x160 [ 21.825369] [] ? sock_recvmsg+0x110/0x110 [ 21.831142] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 21.839601] [] do_iter_readv_writev+0x301/0x4b0 [ 21.845889] [] ? vfs_iter_write+0x460/0x460 [ 21.851832] [] ? rw_verify_area+0xe5/0x2b0 [ 21.857687] [] do_readv_writev+0x2f6/0x7a0 [ 21.863538] [] ? vfs_write+0x530/0x530 [ 21.869044] [] ? SYSC_sendto+0x24b/0x370 [ 21.874725] [] ? __fget+0x20a/0x3b0 [ 21.879977] [] ? __fget+0x231/0x3b0 [ 21.885229] [] ? __fget+0x47/0x3b0 [ 21.890387] [] vfs_readv+0x84/0xc0 [ 21.895546] [] do_readv+0xe6/0x260 [ 21.900704] [] ? vfs_readv+0xc0/0xc0 [ 21.906038] [] SyS_readv+0x27/0x30 [ 21.911216] [] ? rw_copy_check_uvector+0x330/0x330 [ 21.917771] [] do_syscall_64+0x1a6/0x490 [ 21.923456] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 21.930348] [ 21.931948] Allocated by task 4146: [ 21.935545] save_stack_trace+0x16/0x20 [ 21.939489] save_stack+0x43/0xd0 [ 21.942911] kasan_kmalloc+0xc7/0xe0 [ 21.946596] kasan_slab_alloc+0x12/0x20 [ 21.950542] __kmalloc_track_caller+0xdc/0x2b0 [ 21.955095] __kmalloc_reserve.isra.37+0x33/0xc0 [ 21.959820] __alloc_skb+0x11a/0x600 [ 21.963504] alloc_skb_with_frags+0xaf/0x520 [ 21.967881] sock_alloc_send_pskb+0x5a9/0x750 [ 21.972345] packet_sendmsg+0x1581/0x4470 [ 21.976463] sock_sendmsg+0xcc/0x110 [ 21.980145] SYSC_sendto+0x21c/0x370 [ 21.983829] SyS_sendto+0x40/0x50 [ 21.987255] do_syscall_64+0x1a6/0x490 [ 21.991114] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 21.996184] [ 21.997787] Freed by task 4146: [ 22.001039] save_stack_trace+0x16/0x20 [ 22.004984] save_stack+0x43/0xd0 [ 22.008407] kasan_slab_free+0x72/0xc0 [ 22.012265] kfree+0xfb/0x310 [ 22.015349] skb_free_head+0x8b/0xb0 [ 22.019034] skb_release_data+0x329/0x400 [ 22.023153] skb_release_all+0x4a/0x60 [ 22.027008] __kfree_skb+0x15/0x20 [ 22.030517] kfree_skb+0xcc/0x340 [ 22.033941] sit_tunnel_xmit+0xfb/0x2590 [ 22.037972] dev_hard_start_xmit+0x197/0x8b0 [ 22.042351] __dev_queue_xmit+0x19a5/0x2080 [ 22.046641] dev_queue_xmit+0x17/0x20 [ 22.050409] packet_sendmsg+0x1eff/0x4470 [ 22.054527] sock_sendmsg+0xcc/0x110 [ 22.058218] SYSC_sendto+0x21c/0x370 [ 22.061901] SyS_sendto+0x40/0x50 [ 22.065323] do_syscall_64+0x1a6/0x490 [ 22.069181] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 22.074253] [ 22.075852] The buggy address belongs to the object at ffff8801da2c8a00 [ 22.075852] which belongs to the cache kmalloc-512 of size 512 [ 22.088477] The buggy address is located 128 bytes inside of [ 22.088477] 512-byte region [ffff8801da2c8a00, ffff8801da2c8c00) [ 22.100318] The buggy address belongs to the page: [ 22.105220] page:ffffea000768b200 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 22.115389] flags: 0x8000000000004080(slab|head) [ 22.120112] page dumped because: kasan: bad access detected [ 22.125789] [ 22.127384] Memory state around the buggy address: [ 22.132281] ffff8801da2c8980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 22.139612] ffff8801da2c8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 22.146940] >ffff8801da2c8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 22.154266] ^ [ 22.157602] ffff8801da2c8b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 22.164931] ffff8801da2c8b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 22.172258] ================================================================== [ 22.179586] Disabling lock debugging due to kernel taint [ 22.185996] Kernel panic - not syncing: panic_on_warn set ... [ 22.185996] [ 22.193363] CPU: 0 PID: 4145 Comm: syz-executor184 Tainted: G B 4.9.100-g73fdfa3 #26 [ 22.202342] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 22.211669] ffff8801d7a5f558 ffffffff81eb0f09 ffffffff843c50e5 00000000ffffffff [ 22.219665] 0000000000000000 0000000000000000 ffff8801da2c8a80 ffff8801d7a5f618 [ 22.227644] ffffffff8141f895 0000000041b58ab3 ffffffff843b87e8 ffffffff8141f6d6 [ 22.235620] Call Trace: [ 22.238187] [] dump_stack+0xc1/0x128 [ 22.243527] [] panic+0x1bf/0x3bc [ 22.248951] [] ? add_taint.cold.6+0x16/0x16 [ 22.254900] [] ? ___preempt_schedule+0x16/0x18 [ 22.261106] [] kasan_end_report+0x47/0x4f [ 22.266873] [] kasan_report.cold.6+0x76/0x2fe [ 22.272990] [] ? copy_to_iter+0x239/0x10e0 [ 22.278846] [] check_memory_region+0x14f/0x1b0 [ 22.285050] [] kasan_check_read+0x11/0x20 [ 22.290819] [] copy_to_iter+0x239/0x10e0 [ 22.296500] [] ? iov_iter_get_pages+0xd60/0xd60 [ 22.302790] [] ? check_preemption_disabled+0x3b/0x170 [ 22.309609] [] skb_copy_datagram_iter+0x1d1/0x8f0 [ 22.316074] [] ? sock_has_perm+0x1c2/0x3e0 [ 22.321933] [] packet_recvmsg+0x263/0xf40 [ 22.327702] [] ? packet_rcv_has_room+0xa0/0xa0 [ 22.334265] [] ? avc_has_perm_noaudit+0x450/0x450 [ 22.340731] [] ? selinux_socket_recvmsg+0x3f/0x50 [ 22.347198] [] ? security_socket_recvmsg+0x97/0xc0 [ 22.353748] [] ? packet_rcv_has_room+0xa0/0xa0 [ 22.359954] [] sock_recvmsg+0xc6/0x110 [ 22.365463] [] sock_read_iter+0x24a/0x360 [ 22.371233] [] ? inode_has_perm.isra.32+0x111/0x160 [ 22.377876] [] ? sock_recvmsg+0x110/0x110 [ 22.383647] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 22.392109] [] do_iter_readv_writev+0x301/0x4b0 [ 22.398419] [] ? vfs_iter_write+0x460/0x460 [ 22.404365] [] ? rw_verify_area+0xe5/0x2b0 [ 22.410219] [] do_readv_writev+0x2f6/0x7a0 [ 22.416074] [] ? vfs_write+0x530/0x530 [ 22.421584] [] ? SYSC_sendto+0x24b/0x370 [ 22.427274] [] ? __fget+0x20a/0x3b0 [ 22.432532] [] ? __fget+0x231/0x3b0 [ 22.437781] [] ? __fget+0x47/0x3b0 [ 22.442949] [] vfs_readv+0x84/0xc0 [ 22.448120] [] do_readv+0xe6/0x260 [ 22.453287] [] ? vfs_readv+0xc0/0xc0 [ 22.458625] [] SyS_readv+0x27/0x30 [ 22.463792] [] ? rw_copy_check_uvector+0x330/0x330 [ 22.470345] [] do_syscall_64+0x1a6/0x490 [ 22.476038] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 22.483420] Dumping ftrace buffer: [ 22.486943] (ftrace buffer empty) [ 22.490624] Kernel Offset: disabled [ 22.494224] Rebooting in 86400 seconds..