[ 19.923277] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 20.101545] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [ 20.417702] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.361826] random: sshd: uninitialized urandom read (32 bytes read, 111 bits of entropy available) [ 21.521479] random: sshd: uninitialized urandom read (32 bytes read, 113 bits of entropy available) Warning: Permanently added '10.128.0.16' (ECDSA) to the list of known hosts. [ 26.937567] random: sshd: uninitialized urandom read (32 bytes read, 121 bits of entropy available) executing program [ 27.033714] ================================================================== [ 27.041090] BUG: KASAN: use-after-free in ip6_xmit+0x1a2c/0x1a70 [ 27.047202] Read of size 8 at addr ffff8800b625b8d8 by task syzkaller986041/3657 [ 27.054697] [ 27.056294] CPU: 1 PID: 3657 Comm: syzkaller986041 Not tainted 4.4.120-gd63fdf6 #28 [ 27.064052] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.073376] 0000000000000000 120abb99dcb7a4f5 ffff8800ae83f6a8 ffffffff81d0408d [ 27.081333] ffffea0002d896c0 ffff8800b625b8d8 0000000000000000 ffff8800b625b8d8 [ 27.089288] 0000000000000040 ffff8800ae83f6e0 ffffffff814fe143 ffff8800b625b8d8 [ 27.097254] Call Trace: [ 27.099809] [<ffffffff81d0408d>] dump_stack+0xc1/0x124 [ 27.105141] [<ffffffff814fe143>] print_address_description+0x73/0x260 [ 27.111772] [<ffffffff814fe655>] kasan_report+0x285/0x370 [ 27.117361] [<ffffffff8330649c>] ? ip6_xmit+0x1a2c/0x1a70 [ 27.122952] [<ffffffff814fe7b4>] __asan_report_load8_noabort+0x14/0x20 [ 27.129671] [<ffffffff8330649c>] ip6_xmit+0x1a2c/0x1a70 [ 27.135088] [<ffffffff814fa56c>] ? kfree+0xfc/0x300 [ 27.140157] [<ffffffff82e1099b>] ? pskb_expand_head+0x28b/0x980 [ 27.146270] [<ffffffff83459a1e>] ? l2tp_xmit_skb+0xa5e/0xea0 [ 27.152120] [<ffffffff83304a70>] ? ip6_finish_output2+0x1c60/0x1c60 [ 27.158578] [<ffffffff81230151>] ? __lock_is_held+0xa1/0xf0 [ 27.164345] [<ffffffff830c2091>] ? ipv4_dst_check+0x111/0x160 [ 27.170285] [<ffffffff82df2c88>] ? __sk_dst_check+0x148/0x260 [ 27.176222] [<ffffffff833c70f6>] inet6_csk_xmit+0x246/0x480 [ 27.181987] [<ffffffff833c6fb0>] ? inet6_csk_xmit+0x100/0x480 [ 27.187928] [<ffffffff833c6eb0>] ? inet6_csk_update_pmtu+0x160/0x160 [ 27.194477] [<ffffffff83418d76>] ? udp6_set_csum+0x336/0xa80 [ 27.200329] [<ffffffff83459bef>] l2tp_xmit_skb+0xc2f/0xea0 [ 27.206008] [<ffffffff834666d4>] pppol2tp_sendmsg+0x584/0x7f0 [ 27.211947] [<ffffffff81b68adf>] ? selinux_socket_sendmsg+0x3f/0x50 [ 27.218411] [<ffffffff83466150>] ? pppol2tp_release+0x310/0x310 [ 27.224525] [<ffffffff82deba6a>] sock_sendmsg+0xca/0x110 [ 27.230030] [<ffffffff82ded641>] ___sys_sendmsg+0x6c1/0x7c0 [ 27.235794] [<ffffffff82decf80>] ? copy_msghdr_from_user+0x550/0x550 [ 27.242341] [<ffffffff81d63e4b>] ? check_preemption_disabled+0x3b/0x200 [ 27.249147] [<ffffffff8150e179>] ? do_huge_pmd_anonymous_page+0x549/0xa10 [ 27.256128] [<ffffffff83772e2c>] ? _raw_spin_unlock+0x2c/0x50 [ 27.262069] [<ffffffff8150e00d>] ? do_huge_pmd_anonymous_page+0x3dd/0xa10 [ 27.269051] [<ffffffff81285eb7>] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 27.275772] [<ffffffff81578953>] ? __fget_light+0xa3/0x1e0 [ 27.281446] [<ffffffff81578aa8>] ? __fdget+0x18/0x20 [ 27.286601] [<ffffffff82def693>] __sys_sendmsg+0xd3/0x190 [ 27.292190] [<ffffffff82def5c0>] ? SyS_shutdown+0x1b0/0x1b0 [ 27.297954] [<ffffffff810dc6f0>] ? __do_page_fault+0x380/0xa00 [ 27.303981] [<ffffffff81236bdb>] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.310787] [<ffffffff82def77d>] SyS_sendmsg+0x2d/0x50 [ 27.316125] [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 27.322667] [ 27.324260] Allocated by task 3634: [ 27.327849] [<ffffffff81035d96>] save_stack_trace+0x26/0x50 [ 27.333731] [<ffffffff814fd1b3>] save_stack+0x43/0xd0 [ 27.339089] [<ffffffff814fd47d>] kasan_kmalloc+0xad/0xe0 [ 27.344704] [<ffffffff814fda52>] kasan_slab_alloc+0x12/0x20 [ 27.350584] [<ffffffff814f912a>] kmem_cache_alloc+0xba/0x290 [ 27.356548] [<ffffffff82e6964f>] dst_alloc+0x11f/0x1a0 [ 27.361995] [<ffffffff830c27d8>] rt_dst_alloc+0x78/0x430 [ 27.367622] [<ffffffff830cbc6e>] __ip_route_output_key_hash+0xa4e/0x2390 [ 27.374629] [<ffffffff83195fc5>] __ip4_datagram_connect+0xa15/0x1150 [ 27.381290] [<ffffffff833b8109>] __ip6_datagram_connect+0x4d9/0x1950 [ 27.387955] [<ffffffff833b95af>] ip6_datagram_connect+0x2f/0x50 [ 27.394178] [<ffffffff831d0a1b>] inet_dgram_connect+0x16b/0x1f0 [ 27.400403] [<ffffffff82dec596>] SYSC_connect+0x1b6/0x310 [ 27.406107] [<ffffffff82deee04>] SyS_connect+0x24/0x30 [ 27.411547] [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 27.418208] [ 27.419802] Freed by task 0: [ 27.422784] [<ffffffff81035d96>] save_stack_trace+0x26/0x50 [ 27.428664] [<ffffffff814fd1b3>] save_stack+0x43/0xd0 [ 27.434021] [<ffffffff814fdad2>] kasan_slab_free+0x72/0xc0 [ 27.439809] [<ffffffff814fa217>] kmem_cache_free+0xc7/0x320 [ 27.445688] [<ffffffff82e6a2ee>] dst_destroy+0x20e/0x330 [ 27.451307] [<ffffffff82e6a935>] dst_destroy_rcu+0x15/0x40 [ 27.457097] [<ffffffff812950d4>] rcu_process_callbacks+0x7f4/0x14a0 [ 27.463669] [<ffffffff83776e57>] __do_softirq+0x227/0xa38 [ 27.469379] [ 27.470975] The buggy address belongs to the object at ffff8800b625b8c0 [ 27.470975] which belongs to the cache ip_dst_cache of size 208 [ 27.483683] The buggy address is located 24 bytes inside of [ 27.483683] 208-byte region [ffff8800b625b8c0, ffff8800b625b990) [ 27.495436] The buggy address belongs to the page: SeaBIOS (version 1.8.2-20171120_144221-google) Total RAM Size = 0x00000001e0000000 = 7680 MiB CPUs found: 2 Max CPUs supported: 256 found virtio-scsi at 0:3 virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0 virtio-scsi blksize=512 sectors=4194304 = 2048 MiB drive 0x000f2360: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304 Booting from Hard Disk 0... early console in decompress_kernel input_data: 0x00000000037cb26e input_len: 0x0000000001423b2c output: 0x0000000001000000 output_len: 0x0000000003bdaa40 run_size: 0x0000000005310000 Decompressing Linux... Parsing ELF... done. Booting the kernel. [ 0.000000] Initializing cgroup subsys cpuset [ 0.000000] Initializing cgroup subsys cpu [ 0.000000] Initializing cgroup subsys cpuacct [ 0.000000] Initializing cgroup subsys schedtune [ 0.000000] Linux version 4.4.120-gd63fdf6 (syzkaller@ci) (gcc version 7.1.1 20170620 (GCC) ) #28 SMP PREEMPT Tue Mar 6 13:16:06 UTC 2018 [ 0.000000] Command line: BOOT_IMAGE=/vmlinuz root=/dev/sda1 console=ttyS0 earlyprintk=serial vsyscall=native rodata=n ftrace_dump_on_oops=orig_cpu oops=panic panic_on_warn=1 nmi_watchdog=panic panic=86400 workqueue.watchdog_thresh=120 [ 0.000000] KERNEL supported cpus: [ 0.000000] Intel GenuineIntel [ 0.000000] AMD AuthenticAMD [ 0.000000] Centaur CentaurHauls [ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256 [ 0.000000] x86/fpu: Supporting XSAVE feature 0x01: 'x87 floating point registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x02: 'SSE registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x04: 'AVX registers' [ 0.000000] x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format. [ 0.000000] x86/fpu: Using 'eager' FPU context switches. [ 0.000000] e820: BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable [ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000bfff2fff] usable [ 0.000000] BIOS-e820: [mem 0x00000000bfff3000-0x00000000bfffffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fffbc000-0x00000000ffffffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000021fffffff] usable [ 0.000000] bootconsole [earlyser0] enabled [ 0.000000] NX (Execute Disable) protection: active [ 0.000000] SMBIOS 2.4 present. [ 0.000000] Hypervisor detected: KVM [ 0.000000] e820: last_pfn = 0x220000 max_arch_pfn = 0x400000000 [ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT [ 0.000000] e820: last_pfn = 0xbfff3 max_arch_pfn = 0x400000000 [ 0.000000] found SMP MP-table at [mem 0x000f23e0-0x000f23ef] mapped at [ffff8800000f23e0] [ 0.000000] Scanning 1 areas for low memory corruption [ 0.000000] Using GB pages for direct mapping [ 0.000000] ACPI: Early table checksum verification disabled [ 0.000000] ACPI: RSDP 0x00000000000F23A0 000014 (v00 Google) [ 0.000000] ACPI: RSDT 0x00000000BFFF3430 000038 (v01 Google GOOGRSDT 00000001 GOOG 00000001) [ 0.000000] ACPI: FACP 0x00000000BFFFCF60 0000F4 (v02 Google GOOGFACP 00000001 GOOG 00000001) [ 0.000000] ACPI: DSDT 0x00000000BFFF3470 0017B2 (v01 Google GOOGDSDT 00000001 GOOG 00000001) [ 0.000000] ACPI: FACS 0x00000000BFFFCF00 000040 [ 0.000000] ACPI: FACS 0x00000000BFFFCF00 000040 [ 0.000000] ACPI: SSDT 0x00000000BFFF65F0 00690D (v01 Google GOOGSSDT 00000001 GOOG 00000001) [ 0.000000] ACPI: APIC 0x00000000BFFF5D10 000076 (v01 Google GOOGAPIC 00000001 GOOG 00000001) [ 0.000000] ACPI: WAET 0x00000000BFFF5CE0 000028 (v01 Google GOOGWAET 00000001 GOOG 00000001) [ 0.000000] ACPI: SRAT 0x00000000BFFF4C30 0000C8 (v01 Google GOOGSRAT 00000001 GOOG 00000001) [ 0.000000] kvm-clock: Using msrs 4b564d01 and 4b564d00 [ 0.000000] kvm-clock: cpu 0, msr 2:1fffd001, primary cpu clock [ 0.000000] kvm-clock: using sched offset of 2388753706 cycles [ 0.000000] clocksource: kvm-clock: mask: 0xffffffffffffffff max_cycles: 0x1cd42e4dffb, max_idle_ns: 881590591483 ns [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff] [ 0.000000] DMA32 [mem 0x0000000001000000-0x00000000ffffffff] [ 0.000000] Normal [mem 0x0000000100000000-0x000000021fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000000001000-0x000000000009efff] [ 0.000000] node 0: [mem 0x0000000000100000-0x00000000bfff2fff] [ 0.000000] node 0: [mem 0x0000000100000000-0x000000021fffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000021fffffff] [ 0.000000] kasan: KernelAddressSanitizer initialized [ 0.000000] ACPI: PM-Timer IO Port: 0xb008 [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1]) [ 0.000000] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23 [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level) [ 0.000000] Using ACPI (MADT) for SMP configuration information [ 0.000000] smpboot: Allowing 2 CPUs, 0 hotplug CPUs [ 0.000000] PM: Registered nosave memory: [mem 0x00000000-0x00000fff] [ 0.000000] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff] [ 0.000000] PM: Registered nosave memory: [mem 0x000a0000-0x000effff] [ 0.000000] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff] [ 0.000000] PM: Registered nosave memory: [mem 0xbfff3000-0xbfffffff] [ 0.000000] PM: Registered nosave memory: [mem 0xc0000000-0xfffbbfff] [ 0.000000] PM: Registered nosave memory: [mem 0xfffbc000-0xffffffff] [ 0.000000] e820: [mem 0xc0000000-0xfffbbfff] available for PCI devices [ 0.000000] Booting paravirtualized kernel on KVM [ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns [ 0.000000] setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:2 nr_node_ids:1 [ 0.000000] PERCPU: Embedded 42 pages/cpu @ffff8801db200000 s134024 r8192 d29816 u1048576 [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 1935227 [ 0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz root=/dev/sda1 console=ttyS0 earlyprintk=serial vsyscall=native rodata=n ftrace_dump_on_oops=orig_cpu oops=panic panic_on_warn=1 nmi_watchdog=panic panic=86400 workqueue.watchdog_thresh=120 [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes) [ 0.000000] Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes) [ 0.000000] Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes) [ 0.000000] Memory: 6581404K/7863876K available (40422K kernel code, 6136K rwdata, 8808K rodata, 1848K init, 23616K bss, 1282472K reserved, 0K cma-reserved) [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1 [ 0.000000] Kernel/User page tables isolation: enabled [ 0.000000] Running RCU self tests [ 0.000000] Preemptible hierarchical RCU implementation. [ 0.000000] RCU lockdep checking is enabled. [ 0.000000] Build-time adjustment of leaf fanout to 64. [ 0.000000] RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=2. [ 0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=64, nr_cpu_ids=2 [ 0.000000] NR_IRQS:4352 nr_irqs:440 16 [ 0.000000] console [ttyS0] enabled [ 0.000000] console [ttyS0] enabled [ 0.000000] bootconsole [earlyser0] disabled [ 0.000000] bootconsole [earlyser0] disabled [ 0.000000] Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar [ 0.000000] ... MAX_LOCKDEP_SUBCLASSES: 8 [ 0.000000] ... MAX_LOCK_DEPTH: 48 [ 0.000000] ... MAX_LOCKDEP_KEYS: 8191 [ 0.000000] ... CLASSHASH_SIZE: 4096 [ 0.000000] ... MAX_LOCKDEP_ENTRIES: 32768 [ 0.000000] ... MAX_LOCKDEP_CHAINS: 65536 [ 0.000000] ... CHAINHASH_SIZE: 32768 [ 0.000000] memory used by lock dependency info: 8159 kB [ 0.000000] per task-struct memory footprint: 1920 bytes [ 0.000000] tsc: Detected 2300.000 MHz processor [ 1.125144] Calibrating delay loop (skipped) preset value.. 4600.00 BogoMIPS (lpj=23000000) [ 1.126315] pid_max: default: 32768 minimum: 301 [ 1.127030] ACPI: Core revision 20150930 [ 1.544973] ACPI: 2 ACPI AML tables successfully acquired and loaded [ 1.546931] Security Framework initialized [ 1.547500] SELinux: Initializing. [ 1.548147] AppArmor: AppArmor disabled by boot time parameter [ 1.549042] Mount-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 1.549968] Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 1.553606] Initializing cgroup subsys io [ 1.554209] Initializing cgroup subsys freezer [ 1.554902] Initializing cgroup subsys hugetlb [ 1.555564] Initializing cgroup subsys debug [ 1.556345] CPU: Physical Processor ID: 0 [ 1.558207] mce: CPU supports 32 MCE banks [ 1.558945] Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024 [ 1.559773] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4 [ 1.560685] Spectre V2 : Vulnerable: Minimal generic ASM retpoline [ 1.563805] Freeing SMP alternatives memory: 44K [ 1.573316] ..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1 [ 1.684443] smpboot: CPU0: Intel(R) Xeon(R) CPU @ 2.30GHz (family: 0x6, model: 0x3f, stepping: 0x0) [ 1.685912] Performance Events: unsupported p6 CPU model 63 no PMU driver, software events only. [ 1.774678] x86: Booting SMP configuration: [ 1.775304] .... node #0, CPUs: #1 [ 1.776066] kvm-clock: cpu 1, msr 2:1fffd041, secondary cpu clock [ 1.780812] x86: Booted up 1 node, 2 CPUs [ 1.781379] smpboot: Total of 2 processors activated (9200.00 BogoMIPS) [ 1.785943] devtmpfs: initialized [ 1.795329] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns [ 1.796697] futex hash table entries: 512 (order: 4, 65536 bytes) [ 1.798295] xor: automatically using best checksumming function: [ 1.801635] kworker/u4:0 (21) used greatest stack depth: 27944 bytes left [ 1.894454] avx : 21693.600 MB/sec [ 1.895576] RTC time: 4:43:40, date: 03/09/18 [ 1.897859] NET: Registered protocol family 16 [ 1.898946] schedtune: init normalization constants... [ 1.899664] schedtune: no energy model data [ 1.900240] schedtune: disabled! [ 1.934640] cpuidle: using governor ladder [ 1.964473] cpuidle: using governor menu [ 1.965761] ACPI: bus type PCI registered [ 1.966321] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5 [ 1.969099] PCI: Using configuration type 1 for base access [ 1.980939] kworker/u4:0 (47) used greatest stack depth: 27448 bytes left [ 2.404423] raid6: sse2x1 gen() 4802 MB/s [ 2.574428] raid6: sse2x1 xor() 2639 MB/s [ 2.744411] raid6: sse2x2 gen() 7594 MB/s [ 2.914395] raid6: sse2x2 xor() 4324 MB/s [ 3.084386] raid6: sse2x4 gen() 9883 MB/s [ 3.254380] raid6: sse2x4 xor() 5687 MB/s [ 3.424368] raid6: avx2x1 gen() 9469 MB/s [ 3.594362] raid6: avx2x2 gen() 14707 MB/s [ 3.764353] raid6: avx2x4 gen() 19291 MB/s [ 3.765030] raid6: using algorithm avx2x4 gen() 19291 MB/s [ 3.765811] raid6: using avx2x2 recovery algorithm [ 3.767154] ACPI: Added _OSI(Module Device) [ 3.767798] ACPI: Added _OSI(Processor Device) [ 3.768484] ACPI: Added _OSI(3.0 _SCP Extensions) [ 3.769203] ACPI: Added _OSI(Processor Aggregator Device) [ 3.794823] ACPI: Executed 2 blocks of module-level executable AML code [ 4.629818] ACPI: Interpreter enabled [ 4.630744] ACPI: (supports S0 S3 S4 S5) [ 4.631340] ACPI: Using IOAPIC for interrupt routing [ 4.632509] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug