[ 21.082831] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available) [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [ 21.485392] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 21.690539] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.529816] random: sshd: uninitialized urandom read (32 bytes read, 91 bits of entropy available) [ 22.711946] random: sshd: uninitialized urandom read (32 bytes read, 97 bits of entropy available) Warning: Permanently added '10.128.0.28' (ECDSA) to the list of known hosts. [ 28.128423] random: sshd: uninitialized urandom read (32 bytes read, 108 bits of entropy available) executing program [ 28.224968] ================================================================== [ 28.232379] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 28.239012] Read of size 8 at addr ffff8801c785f238 by task syzkaller943796/4005 [ 28.246510] [ 28.248112] CPU: 0 PID: 4005 Comm: syzkaller943796 Not tainted 4.4.113-g962d1f3 #2 [ 28.255790] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.265113] 0000000000000000 1b47e47449520520 ffff8800b9e778f0 ffffffff81d028ed [ 28.273081] ffffea00071e1780 ffff8801c785f238 0000000000000000 ffff8801c785f238 [ 28.281045] 0000000000000000 ffff8800b9e77928 ffffffff814fd1c3 ffff8801c785f238 [ 28.289019] Call Trace: [ 28.291578] [] dump_stack+0xc1/0x124 [ 28.296914] [] print_address_description+0x73/0x260 [ 28.303546] [] kasan_report+0x285/0x370 [ 28.309138] [] ? __lock_acquire+0x387e/0x4b50 [ 28.315250] [] __asan_report_load8_noabort+0x14/0x20 [ 28.321978] [] __lock_acquire+0x387e/0x4b50 [ 28.327919] [] ? __lock_acquire+0xb5f/0x4b50 [ 28.333944] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.340923] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.347905] [] ? mark_held_locks+0xaf/0x100 [ 28.353854] [] lock_acquire+0x15e/0x460 [ 28.359456] [] ? remove_wait_queue+0x14/0x40 [ 28.365483] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.371771] [] ? remove_wait_queue+0x14/0x40 [ 28.377799] [] remove_wait_queue+0x14/0x40 [ 28.383654] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 28.390647] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 28.397890] [] ? ep_free+0x1c0/0x1c0 [ 28.403219] [] ep_free+0x93/0x1c0 [ 28.408287] [] ? ep_free+0x1c0/0x1c0 [ 28.413619] [] ep_eventpoll_release+0x44/0x60 [ 28.419732] [] __fput+0x233/0x6d0 [ 28.424803] [] ____fput+0x15/0x20 [ 28.429874] [] task_work_run+0x104/0x180 [ 28.435552] [] do_exit+0x82a/0x2a10 [ 28.440808] [] ? binder_ioctl_write_read.isra.55+0xbc0/0xbc0 [ 28.448224] [] ? release_task+0x1240/0x1240 [ 28.454162] [] ? SyS_epoll_create+0x190/0x190 [ 28.460275] [] do_group_exit+0x108/0x320 [ 28.465952] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 28.472410] [] SyS_exit_group+0x1d/0x20 [ 28.478000] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 28.484542] [ 28.486136] Allocated by task 4005: [ 28.489729] [] save_stack_trace+0x26/0x50 [ 28.495615] [] save_stack+0x43/0xd0 [ 28.500980] [] kasan_kmalloc+0xad/0xe0 [ 28.506603] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.513177] [] binder_get_thread+0x15d/0x750 [ 28.519327] [] binder_poll+0x4a/0x210 [ 28.524858] [] SyS_epoll_ctl+0x10b1/0x2040 [ 28.530823] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 28.537486] [ 28.539083] Freed by task 4005: [ 28.542326] [] save_stack_trace+0x26/0x50 [ 28.548205] [] save_stack+0x43/0xd0 [ 28.553562] [] kasan_slab_free+0x72/0xc0 [ 28.559354] [] kfree+0xfc/0x300 [ 28.564368] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.571120] [] binder_thread_release+0x27d/0x540 [ 28.577611] [] binder_ioctl+0xb94/0x12e0 [ 28.583406] [] do_vfs_ioctl+0x7aa/0xee0 [ 28.589118] [] SyS_ioctl+0x8f/0xc0 [ 28.594391] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 28.601053] [ 28.602650] The buggy address belongs to the object at ffff8801c785f180 [ 28.602650] which belongs to the cache kmalloc-512 of size 512 [ 28.615274] The buggy address is located 184 bytes inside of [ 28.615274] 512-byte region [ffff8801c785f180, ffff8801c785f380) [ 28.627112] The buggy address belongs to the page: [ 28.635786] kasan: CONFIG_KASAN_INLINE enabled [ 28.640205] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN [ 28.653139] Dumping ftrace buffer: [ 28.656662] (ftrace buffer empty) [ 28.660354] Modules linked in: [ 28.663661] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.113-g962d1f3 #2 [ 28.670566] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.679903] task: ffff8801d9b497c0 task.stack: ffff8801d9b58000 [ 28.685944] RIP: 0010:[] [] debug_object_deactivate+0x1a6/0x3c0 [ 28.695336] RSP: 0018:ffff8801db307d20 EFLAGS: 00010003 [ 28.700769] RAX: 0000000000000092 RBX: 4f5f4755425f4d56 RCX: ffff8801db319c40 [ 28.708032] RDX: 09ebe8eaa84be9ad RSI: ffffffff842c6420 RDI: 4f5f4755425f4d6e [ 28.715292] RBP: ffff8801db307de8 R08: 1ffff10017265cb2 R09: ffffffff8510ffd0 [ 28.722553] R10: 0000000000000001 R11: 1ffff1003b660f6a R12: 1ffff1003b660fa8 [ 28.729817] R13: 0000000000000003 R14: dffffc0000000000 R15: ffffffff857d3748 [ 28.737079] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 28.745297] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.751172] CR2: 0000564c9a8eb0d0 CR3: 00000000ba1b6000 CR4: 0000000000160670 [ 28.758444] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 28.765710] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 28.772967] Stack: [ 28.775108] 0000000000000095 ffffffff842c6420 ffff8801db319c40 0000000000000092 [ 28.783165] 0000000041b58ab3 ffffffff83fcdf21 ffffffff81d646b0 ffff8801d9b497c0 [ 28.791206] ffffed003b369405 ffff8801db319658 ffff8801d9b4a030 0000000000000000 [ 28.799263] Call Trace: [ 28.801840] SeaBIOS (version 1.8.2-20171012_061934-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 0x000f2850: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304 Booting from Hard Disk 0... early console in decompress_kernel input_data: 0x00000000039cb26e input_len: 0x0000000001424688 output: 0x0000000001000000 output_len: 0x0000000003ddaa40 run_size: 0x0000000005510000 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 4.4.113-g962d1f3 (syzkaller@ci) (gcc version 7.1.1 20170620 (GCC) ) #2 SMP PREEMPT Mon Jan 29 16:51:40 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 0x000f28d0-0x000f28df] mapped at [ffff8800000f28d0] [ 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 0x00000000000F2890 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 2008199839 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 (40414K kernel code, 6135K rwdata, 8812K rodata, 1852K 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 [ 1.141205] Calibrating delay loop (skipped) preset value.. 4600.00 BogoMIPS (lpj=23000000) [ 1.142368] pid_max: default: 32768 minimum: 301 [ 1.143067] ACPI: Core revision 20150930 [ 1.563570] ACPI: 2 ACPI AML tables successfully acquired and loaded [ 1.565545] Security Framework initialized [ 1.566116] SELinux: Initializing. [ 1.566789] AppArmor: AppArmor disabled by boot time parameter [ 1.567687] Mount-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 1.568639] Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 1.572415] Initializing cgroup subsys io [ 1.573009] Initializing cgroup subsys freezer [ 1.573653] Initializing cgroup subsys hugetlb [ 1.574329] Initializing cgroup subsys debug [ 1.575090] CPU: Physical Processor ID: 0 [ 1.577019] mce: CPU supports 32 MCE banks [ 1.577757] Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024 [ 1.578594] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4 [ 1.579497] Spectre V2 mitigation: Vulnerable: Minimal generic ASM retpoline [ 1.582764] Freeing SMP alternatives memory: 44K [ 1.592197] ..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1 [ 1.710570] smpboot: CPU0: Intel(R) Xeon(R) CPU @ 2.30GHz (family: 0x6, model: 0x3f, stepping: 0x0) [ 1.712042] Performance Events: unsupported p6 CPU model 63 no PMU driver, software events only. [ 1.800822] x86: Booting SMP configuration: [ 1.801508] .... node #0, CPUs: #1 [ 1.802282] kvm-clock: cpu 1, msr 2:1fffd041, secondary cpu clock [ 1.807268] x86: Booted up 1 node, 2 CPUs [ 1.807878] smpboot: Total of 2 processors activated (9200.00 BogoMIPS) [ 1.812510] devtmpfs: initialized [ 1.822088] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns [ 1.823502] futex hash table entries: 512 (order: 4, 65536 bytes) [ 1.825115] xor: automatically using best checksumming function: [ 1.838429] kworker/u4:0 (21) used greatest stack depth: 28008 bytes left [ 1.920621] avx : 21577.200 MB/sec [ 1.921817] RTC time: 9:24:01, date: 01/30/18 [ 1.924116] NET: Registered protocol family 16 [ 1.925246] schedtune: init normalization constants... [ 1.925964] schedtune: no energy model data [ 1.926540] schedtune: disabled! [ 1.960822] cpuidle: using governor ladder [ 1.990658] cpuidle: using governor menu [ 1.991908] ACPI: bus type PCI registered [ 1.992507] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5 [ 1.995337] PCI: Using configuration type 1 for base access [ 2.007119] kworker/u4:0 (46) used greatest stack depth: 27512 bytes left [ 2.450697] raid6: sse2x1 gen() 4807 MB/s [ 2.620705] raid6: sse2x1 xor() 2558 MB/s [ 2.790731] raid6: sse2x2 gen() 7578 MB/s [ 2.960742] raid6: sse2x2 xor() 4304 MB/s [ 3.130766] raid6: sse2x4 gen() 9828 MB/s [ 3.300788] raid6: sse2x4 xor() 5664 MB/s [ 3.470803] raid6: avx2x1 gen() 9448 MB/s [ 3.640822] raid6: avx2x2 gen() 14630 MB/s [ 3.810850] raid6: avx2x4 gen() 19121 MB/s [ 3.811543] raid6: using algorithm avx2x4 gen() 19121 MB/s [ 3.812302] raid6: using avx2x2 recovery algorithm [ 3.813625] ACPI: Added _OSI(Module Device) [ 3.814306] ACPI: Added _OSI(Processor Device) [ 3.814935] ACPI: Added _OSI(3.0 _SCP Extensions) [ 3.815594] ACPI: Added _OSI(Processor Aggregator Device) [ 3.841411] ACPI: Executed 2 blocks of module-level executable AML code [ 4.705934] ACPI: Interpreter enabled [ 4.706938] ACPI: (supports S0 S3 S4 S5) [ 4.707518] ACPI: Using IOAPIC for interrupt routing [ 4.708662] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug