================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:218 [inline] BUG: KASAN: use-after-free in atomic_read arch/x86/include/asm/atomic.h:27 [inline] BUG: KASAN: use-after-free in __atomic_add_unless arch/x86/include/asm/atomic.h:212 [inline] BUG: KASAN: use-after-free in atomic_add_unless include/linux/atomic.h:437 [inline] BUG: KASAN: use-after-free in sk_dst_get include/net/sock.h:1741 [inline] BUG: KASAN: use-after-free in pppol2tp_connect+0x1631/0x1930 net/l2tp/l2tp_ppp.c:755 Read of size 4 at addr ffff8800b566e940 by task syz-executor1/6338 CPU: 1 PID: 6338 Comm: syz-executor1 Not tainted 4.4.115-g0e9bcc1 #12 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 145e512e985da9c0 ffff8800b170fab0 ffffffff81d03dad ffffea0002d59b80 ffff8800b566e940 0000000000000000 ffff8800b566e940 1ffff100162e1f73 ffff8800b170fae8 ffffffff814fe1e3 ffff8800b566e940 Call Trace: audit: type=1400 audit(1518227845.751:7): avc: denied { execute } for pid=6354 comm="syz-executor0" path="pipe:[16539]" dev="pipefs" ino=16539 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=fifo_file permissive=1 [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x124 lib/dump_stack.c:51 [] print_address_description+0x73/0x260 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report+0x285/0x370 mm/kasan/report.c:408 [] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428 [] __read_once_size include/linux/compiler.h:218 [inline] [] atomic_read arch/x86/include/asm/atomic.h:27 [inline] [] __atomic_add_unless arch/x86/include/asm/atomic.h:212 [inline] [] atomic_add_unless include/linux/atomic.h:437 [inline] [] sk_dst_get include/net/sock.h:1741 [inline] [] pppol2tp_connect+0x1631/0x1930 net/l2tp/l2tp_ppp.c:755 [] SYSC_connect+0x1b6/0x310 net/socket.c:1557 [] SyS_connect+0x24/0x30 net/socket.c:1538 [] do_syscall_32_irqs_on arch/x86/entry/common.c:390 [inline] [] do_fast_syscall_32+0x314/0x890 arch/x86/entry/common.c:457 [] sysenter_flags_fixed+0xd/0x17 Allocated by task 5923: [] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [] save_stack+0x43/0xd0 mm/kasan/kasan.c:512 [] set_track mm/kasan/kasan.c:524 [inline] [] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 [] kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:554 [] slab_post_alloc_hook mm/slub.c:1349 [inline] [] slab_alloc_node mm/slub.c:2615 [inline] [] slab_alloc mm/slub.c:2623 [inline] [] kmem_cache_alloc+0xba/0x290 mm/slub.c:2628 [] dst_alloc+0x11f/0x1a0 net/core/dst.c:210 [] rt_dst_alloc+0x78/0x430 net/ipv4/route.c:1467 [] __mkroute_output net/ipv4/route.c:2120 [inline] [] __ip_route_output_key_hash+0xa4e/0x2390 net/ipv4/route.c:2332 [] __ip_route_output_key include/net/route.h:123 [inline] [] ip_route_output_flow+0x29/0xa0 net/ipv4/route.c:2418 [] ip_route_connect include/net/route.h:303 [inline] [] __ip4_datagram_connect+0x652/0x1150 net/ipv4/datagram.c:51 [] __ip6_datagram_connect+0x1401/0x1950 net/ipv6/datagram.c:105 [] ip6_datagram_connect+0x2f/0x50 net/ipv6/datagram.c:223 [] inet_dgram_connect+0x16b/0x1f0 net/ipv4/af_inet.c:550 [] SYSC_connect+0x1b6/0x310 net/socket.c:1557 [] SyS_connect+0x24/0x30 net/socket.c:1538 [] do_syscall_32_irqs_on arch/x86/entry/common.c:390 [inline] [] do_fast_syscall_32+0x314/0x890 arch/x86/entry/common.c:457 [] sysenter_flags_fixed+0xd/0x17 Freed by task 3831: [] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [] save_stack+0x43/0xd0 mm/kasan/kasan.c:512 [] set_track mm/kasan/kasan.c:524 [inline] [] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:589 [] slab_free_hook mm/slub.c:1383 [inline] [] slab_free_freelist_hook mm/slub.c:1405 [inline] [] slab_free mm/slub.c:2859 [inline] [] kmem_cache_free+0xc7/0x320 mm/slub.c:2881 [] dst_destroy+0x20e/0x330 net/core/dst.c:270 [] dst_destroy_rcu+0x15/0x40 net/core/dst.c:295 [] __rcu_reclaim kernel/rcu/rcu.h:118 [inline] [] rcu_do_batch kernel/rcu/tree.c:2705 [inline] [] invoke_rcu_callbacks kernel/rcu/tree.c:2973 [inline] [] __rcu_process_callbacks kernel/rcu/tree.c:2940 [inline] [] rcu_process_callbacks+0x7f4/0x14a0 kernel/rcu/tree.c:2957 [] __do_softirq+0x227/0xa38 kernel/softirq.c:273 The buggy address belongs to the object at ffff8800b566e8c0 which belongs to the cache ip_dst_cache of size 208 The buggy address is located 128 bytes inside of 208-byte region [ffff8800b566e8c0, ffff8800b566e990) The buggy address belongs to the page: audit: type=1400 audit(1518227845.751:8): avc: denied { sigchld } for pid=3825 comm="syz-executor2" scontext=system_u:object_r:unlabeled_t:s0 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=process permissive=1 Initializing cgroup subsys cpuset Initializing cgroup subsys cpu Initializing cgroup subsys cpuacct Initializing cgroup subsys schedtune Linux version 4.4.115-g0e9bcc1 (syzkaller@ci) (gcc version 7.1.1 20170620 (GCC) ) #12 SMP PREEMPT Fri Feb 9 14:00:18 UTC 2018 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 KERNEL supported cpus: Intel GenuineIntel AMD AuthenticAMD Centaur CentaurHauls x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256 x86/fpu: Supporting XSAVE feature 0x01: 'x87 floating point registers' x86/fpu: Supporting XSAVE feature 0x02: 'SSE registers' x86/fpu: Supporting XSAVE feature 0x04: 'AVX registers' x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format. x86/fpu: Using 'eager' FPU context switches. e820: BIOS-provided physical RAM map: BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved BIOS-e820: [mem 0x0000000000100000-0x00000000bfff2fff] usable BIOS-e820: [mem 0x00000000bfff3000-0x00000000bfffffff] reserved BIOS-e820: [mem 0x00000000fffbc000-0x00000000ffffffff] reserved BIOS-e820: [mem 0x0000000100000000-0x000000021fffffff] usable bootconsole [earlyser0] enabled NX (Execute Disable) protection: active SMBIOS 2.4 present. Hypervisor detected: KVM e820: last_pfn = 0x220000 max_arch_pfn = 0x400000000 x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT e820: last_pfn = 0xbfff3 max_arch_pfn = 0x400000000 found SMP MP-table at [mem 0x000f23b0-0x000f23bf] mapped at [ffff8800000f23b0] Scanning 1 areas for low memory corruption Using GB pages for direct mapping ACPI: Early table checksum verification disabled ACPI: RSDP 0x00000000000F2370 000014 (v00 Google) ACPI: RSDT 0x00000000BFFF3430 000038 (v01 Google GOOGRSDT 00000001 GOOG 00000001) ACPI: FACP 0x00000000BFFFCF60 0000F4 (v02 Google GOOGFACP 00000001 GOOG 00000001) ACPI: DSDT 0x00000000BFFF3470 0017B2 (v01 Google GOOGDSDT 00000001 GOOG 00000001) ACPI: FACS 0x00000000BFFFCF00 000040 ACPI: FACS 0x00000000BFFFCF00 000040 ACPI: SSDT 0x00000000BFFF65F0 00690D (v01 Google GOOGSSDT 00000001 GOOG 00000001) ACPI: APIC 0x00000000BFFF5D10 000076 (v01 Google GOOGAPIC 00000001 GOOG 00000001) ACPI: WAET 0x00000000BFFF5CE0 000028 (v01 Google GOOGWAET 00000001 GOOG 00000001) ACPI: SRAT 0x00000000BFFF4C30 0000C8 (v01 Google GOOGSRAT 00000001 GOOG 00000001) kvm-clock: Using msrs 4b564d01 and 4b564d00 kvm-clock: cpu 0, msr 2:1fffd001, primary cpu clock kvm-clock: using sched offset of 1907388269 cycles clocksource: kvm-clock: mask: 0xffffffffffffffff max_cycles: 0x1cd42e4dffb, max_idle_ns: 881590591483 ns Zone ranges: DMA [mem 0x0000000000001000-0x0000000000ffffff] DMA32 [mem 0x0000000001000000-0x00000000ffffffff] Normal [mem 0x0000000100000000-0x000000021fffffff] Movable zone start for each node Early memory node ranges node 0: [mem 0x0000000000001000-0x000000000009efff] node 0: [mem 0x0000000000100000-0x00000000bfff2fff] node 0: [mem 0x0000000100000000-0x000000021fffffff] Initmem setup node 0 [mem 0x0000000000001000-0x000000021fffffff] kasan: KernelAddressSanitizer initialized ACPI: PM-Timer IO Port: 0xb008 ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1]) IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23 ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level) ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level) Using ACPI (MADT) for SMP configuration information smpboot: Allowing 2 CPUs, 0 hotplug CPUs PM: Registered nosave memory: [mem 0x00000000-0x00000fff] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff] PM: Registered nosave memory: [mem 0x000a0000-0x000effff] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff] PM: Registered nosave memory: [mem 0xbfff3000-0xbfffffff] PM: Registered nosave memory: [mem 0xc0000000-0xfffbbfff] PM: Registered nosave memory: [mem 0xfffbc000-0xffffffff] e820: [mem 0xc0000000-0xfffbbfff] available for PCI devices Booting paravirtualized kernel on KVM clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:2 nr_node_ids:1 PERCPU: Embedded 42 pages/cpu @ffff8801db200000 s134024 r8192 d29816 u1048576 Built 1 zonelists in Zone order, mobility grouping on. Total pages: 1935227 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 PID hash table entries: 4096 (order: 3, 32768 bytes) Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes) Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes) Memory: 6581404K/7863876K available (40424K kernel code, 6135K rwdata, 8816K rodata, 1852K init, 23616K bss, 1282472K reserved, 0K cma-reserved) SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1 Kernel/User page tables isolation: enabled Running RCU self tests Preemptible hierarchical RCU implementation. RCU lockdep checking is enabled. Build-time adjustment of leaf fanout to 64. RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=2. RCU: Adjusting geometry for rcu_fanout_leaf=64, nr_cpu_ids=2 NR_IRQS:4352 nr_irqs:440 16 console [ttyS0] enabled console [ttyS0] enabled bootconsole [earlyser0] disabled bootconsole [earlyser0] disabled Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar ... MAX_LOCKDEP_SUBCLASSES: 8 ... MAX_LOCK_DEPTH: 48 ... MAX_LOCKDEP_KEYS: 8191 ... CLASSHASH_SIZE: 4096 ... MAX_LOCKDEP_ENTRIES: 32768 ... MAX_LOCKDEP_CHAINS: 65536 ... CHAINHASH_SIZE: 32768 memory used by lock dependency info: 8159 kB per task-struct memory footprint: 1920 bytes tsc: Detected 2300.000 MHz processor Calibrating delay loop (skipped) preset value.. 4600.00 BogoMIPS (lpj=23000000) pid_max: default: 32768 minimum: 301 ACPI: Core revision 20150930 ACPI: 2 ACPI AML tables successfully acquired and loaded Security Framework initialized SELinux: Initializing. AppArmor: AppArmor disabled by boot time parameter Mount-cache hash table entries: 16384 (order: 5, 131072 bytes) Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes) Initializing cgroup subsys io Initializing cgroup subsys freezer Initializing cgroup subsys hugetlb Initializing cgroup subsys debug CPU: Physical Processor ID: 0 mce: CPU supports 32 MCE banks Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024 Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4 Spectre V2 mitigation: Vulnerable: Minimal generic ASM retpoline Freeing SMP alternatives memory: 44K ..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1 smpboot: CPU0: Intel(R) Xeon(R) CPU @ 2.30GHz (family: 0x6, model: 0x3f, stepping: 0x0) Performance Events: unsupported p6 CPU model 63 no PMU driver, software events only. x86: Booting SMP configuration: .... node #0, CPUs: #1 kvm-clock: cpu 1, msr 2:1fffd041, secondary cpu clock x86: Booted up 1 node, 2 CPUs smpboot: Total of 2 processors activated (9200.00 BogoMIPS) devtmpfs: initialized clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns futex hash table entries: 512 (order: 4, 65536 bytes) xor: automatically using best checksumming function: kworker/u4:0 (21) used greatest stack depth: 27448 bytes left avx : 21999.200 MB/sec RTC time: 1:57:30, date: 02/10/18 NET: Registered protocol family 16 schedtune: init normalization constants... schedtune: no energy model data schedtune: disabled! cpuidle: using governor ladder cpuidle: using governor menu ACPI: bus type PCI registered acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5 PCI: Using configuration type 1 for base access kworker/u4:1 (251) used greatest stack depth: 27080 bytes left raid6: sse2x1 gen() 4789 MB/s raid6: sse2x1 xor() 2488 MB/s raid6: sse2x2 gen() 7076 MB/s raid6: sse2x2 xor() 4026 MB/s raid6: sse2x4 gen() 8760 MB/s raid6: sse2x4 xor() 5328 MB/s raid6: avx2x1 gen() 9467 MB/s raid6: avx2x2 gen() 14774 MB/s raid6: avx2x4 gen() 19433 MB/s raid6: using algorithm avx2x4 gen() 19433 MB/s raid6: using avx2x2 recovery algorithm ACPI: Added _OSI(Module Device) ACPI: Added _OSI(Processor Device) ACPI: Added _OSI(3.0 _SCP Extensions) ACPI: Added _OSI(Processor Aggregator Device) ACPI: Executed 2 blocks of module-level executable AML code ACPI: Interpreter enabled ACPI: (supports S0 S3 S4 S5) ACPI: Using IOAPIC for interrupt routing PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff]) acpi PNP0A03:00: _OSC: OS supports [ASPM ClockPM Segments MSI] acpi PNP0A03:00: _OSC failed (AE_NOT_FOUND); disabling ASPM acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge. PCI host bridge to bus 0000:00 pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window] pci_bus 0000:00: root bus resource [mem 0xc0000000-0xfebfffff window] pci_bus 0000:00: root bus resource [bus 00-ff] pci 0000:00:01.3: quirk: [io 0xb000-0xb03f] claimed by PIIX4 ACPI ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11) ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11) ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11) ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11) ACPI: PCI Interrupt Link [LNKS] (IRQs *9) ACPI: Enabled 16 GPEs in block 00 to 0F vgaarb: loaded SCSI subsystem initialized ACPI: bus type USB registered usbcore: registered new interface driver usbfs usbcore: registered new interface driver hub usbcore: registered new device driver usb pps_core: LinuxPPS API ver. 1 registered pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti PTP clock support registered ioremap error for 0xbfffd000-0xc0000000, requested 0x2, got 0x0 dmi: Firmware registration failed. Advanced Linux Sound Architecture Driver Initialized. PCI: Using ACPI for IRQ routing NetLabel: Initializing NetLabel: domain hash size = 128 NetLabel: protocols = UNLABELED CIPSOv4 NetLabel: unlabeled traffic allowed by default amd_nb: Cannot enumerate AMD northbridges clocksource: Switched to clocksource kvm-clock pnp: PnP ACPI init pnp: PnP ACPI: found 7 devices clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns NET: Registered protocol family 2 TCP established hash table entries: 65536 (order: 7, 524288 bytes) TCP bind hash table entries: 65536 (order: 10, 4194304 bytes) TCP: Hash tables configured (established 65536 bind 65536) UDP hash table entries: 4096 (order: 7, 655360 bytes) UDP-Lite hash table entries: 4096 (order: 7, 655360 bytes) NET: Registered protocol family 1 pci 0000:00:00.0: Limiting direct PCI/PCI transfers PCI-DMA: Using software bounce buffering for IO (SWIOTLB) software IO TLB [mem 0xbbff3000-0xbfff3000] (64MB) mapped at [ffff8800bbff3000-ffff8800bfff2fff] RAPL PMU detected, API unit is 2^-32 Joules, 3 fixed counters 10737418240 ms ovfl timer hw unit of domain pp0-core 2^-0 Joules hw unit of domain package 2^-0 Joules hw unit of domain dram 2^-16 Joules Scanning for low memory corruption every 60 seconds audit: initializing netlink subsys (disabled) audit: type=2000 audit(1518227855.091:1): initialized HugeTLB registered 2 MB page size, pre-allocated 0 pages VFS: Disk quotas dquot_6.6.0 VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes) fuse init (API version 7.23) 9p: Installing v9fs 9p2000 file system support async_tx: api initialized (async) Block layer SCSI generic (bsg) driver version 0.4 loaded (major 249) io scheduler noop registered io scheduler deadline registered io scheduler cfq registered (default) pci_hotplug: PCI Hot Plug PCI Core version: 0.5 input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0 ACPI: Power Button [PWRF] input: Sleep Button as /devices/LNXSYSTM:00/LNXSLPBN:00/input/input1 ACPI: Sleep Button [SLPF] ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 11 virtio-pci 0000:00:03.0: virtio_pci: leaving for legacy driver ACPI: PCI Interrupt Link [LNKD] enabled at IRQ 10 virtio-pci 0000:00:04.0: virtio_pci: leaving for legacy driver Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled 00:03: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A 00:04: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A 00:05: ttyS2 at I/O 0x3e8 (irq = 6, base_baud = 115200) is a 16550A 00:06: ttyS3 at I/O 0x2e8 (irq = 7, base_baud = 115200) is a 16550A Non-volatile memory driver v1.3 Linux agpgart interface v0.103 [drm] Initialized drm 1.1.0 20060810 brd: module loaded loop: module loaded nbd: registered device at major 43