KASAN: stack-out-of-bounds Read in __run_timers

From: syzbot
Date: Thu Jul 05 2018 - 00:49:24 EST

Hello,

syzbot found the following crash on:

HEAD commit: 2bdea157b999 Merge branch 'sctp-fully-support-for-dscp-and..
git tree: bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=15438ad0400000
kernel config: https://syzkaller.appspot.com/x/.config?x=f62553dc846b0692
dashboard link: https://syzkaller.appspot.com/bug?extid=833f0280096341307b18
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=12c1f4c2400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16310594400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+833f0280096341307b18@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: stack-out-of-bounds in lookup_object lib/debugobjects.c:157 [inline]
BUG: KASAN: stack-out-of-bounds in debug_object_deactivate+0x425/0x450 lib/debugobjects.c:540
Read of size 8 at addr ffff8801ca8254e8 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.18.0-rc3+ #45
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
print_address_description+0x6c/0x20b mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
lookup_object lib/debugobjects.c:157 [inline]
debug_object_deactivate+0x425/0x450 lib/debugobjects.c:540
debug_timer_deactivate kernel/time/timer.c:714 [inline]
debug_deactivate kernel/time/timer.c:770 [inline]
detach_timer kernel/time/timer.c:815 [inline]
expire_timers kernel/time/timer.c:1353 [inline]
__run_timers+0x571/0xc70 kernel/time/timer.c:1666
run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
__do_softirq+0x2e8/0xb17 kernel/softirq.c:288
? __sanitizer_cov_trace_const_cmp4+SeaBIOS (version 1.8.2-20171130_102032-google)
Linux version 4.18.0-rc3+ (syzkaller@ci) (gcc version 8.0.1 20180413 (experimental) (GCC)) #45 SMP Wed Jul 4 07:02:20 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 kvm-intel.nested=1 nf-conntrack-ftp.ports=20000 nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000 nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000 nopcid
x86/fpu: Supporting XSAVE feature 0x001: 'x87 floating point registers'
x86/fpu: Supporting XSAVE feature 0x002: 'SSE registers'
x86/fpu: Supporting XSAVE feature 0x004: 'AVX registers'
x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256
x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format.
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
Malformed early option 'vsyscall'
nopcid: PCID feature disabled
NX (Execute Disable) protection: active
SMBIOS 2.4 present.
DMI: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Hypervisor detected: KVM
last_pfn = 0x220000 max_arch_pfn = 0x400000000
x86/PAT: Configuration [0-7]: WB WC UC- UC WB WP UC- WT
last_pfn = 0xbfff3 max_arch_pfn = 0x400000000
found SMP MP-table at [mem 0x000f2310-0x000f231f] mapped at [(____ptrval____)]
Scanning 1 areas for low memory corruption
Using GB pages for direct mapping
ACPI: Early table checksum verification disabled
ACPI: RSDP 0x00000000000F22D0 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)
SRAT: PXM 0 -> APIC 0x00 -> Node 0
SRAT: PXM 0 -> APIC 0x01 -> Node 0
ACPI: SRAT: Node 0 PXM 0 [mem 0x00000000-0x0009ffff]
ACPI: SRAT: Node 0 PXM 0 [mem 0x00100000-0xbfffffff]
ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0x21fffffff]
NUMA: Node 0 [mem 0x00000000-0x0009ffff] + [mem 0x00100000-0xbfffffff] -> [mem 0x00000000-0xbfffffff]
NUMA: Node 0 [mem 0x00000000-0xbfffffff] + [mem 0x100000000-0x21fffffff] -> [mem 0x00000000-0x21fffffff]
NODE_DATA(0) allocated [mem 0x21fffa000-0x21fffdfff]
kvm-clock: cpu 0, msr 2:1fff8001, primary cpu clock
kvm-clock: Using msrs 4b564d01 and 4b564d00
kvm-clock: using sched offset of 5084926845 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]
Reserved but unavailable: 111 pages
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]
[mem 0xc0000000-0xfffbbfff] available for PCI devices
Booting paravirtualized kernel on KVM
clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns
random: get_random_bytes called from boot_init_stack_canary arch/x86/include/asm/stackprotector.h:75 [inline] with crng_init=0
random: get_random_bytes called from start_kernel+0x112/0x949 init/main.c:559 with crng_init=0
setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:2 nr_node_ids:1
percpu: Embedded 56 pages/cpu @(____ptrval____) s188616 r8192 d32568 u1048576
Built 1 zonelists, mobility grouping on. Total pages: 1935228
Policy zone: Normal
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 kvm-intel.nested=1 nf-conntrack-ftp.ports=20000 nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000 nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000 nopcid
Memory: 6499788K/7863876K available (110620K kernel code, 12321K rwdata, 16056K rodata, 3968K init, 23144K bss, 1364088K reserved, 0K cma-reserved)
Running RCU self tests
Hierarchical RCU implementation.
RCU lockdep checking is enabled.
RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=2.
RCU callback double-/use-after-free debug enabled.
RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2
NR_IRQS: 4352, nr_irqs: 440, preallocated irqs: 16
Console: colour VGA+ 80x25
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: 7391 kB
per task-struct memory footprint: 1920 bytes
ACPI: Core revision 20180531
APIC: Switch to symmetric I/O mode setup
x2apic enabled
Switched APIC routing to physical x2apic.
..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1
tsc: Detected 2300.000 MHz processor
clocksource: tsc-early: mask: 0xffffffffffffffff max_cycles: 0x212735223b2, max_idle_ns: 440795277976 ns
Calibrating delay loop (skipped) preset value.. 4600.00 BogoMIPS (lpj=2300000)
pid_max: default: 32768 minimum: 301
Security Framework initialized
Yama: becoming mindful.
SELinux: Initializing.
AppArmor: AppArmor disabled by boot time parameter
Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes)
Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes)
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes)
Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes)
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: Full generic retpoline
Speculative Store Bypass: Vulnerable
Freeing SMP alternatives memory: 64K
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.
Hierarchical SRCU implementation.
NMI watchdog: Perf event create on CPU 0 failed with -2
NMI watchdog: Perf NMI watchdog permanently disabled
smp: Bringing up secondary CPUs ...
x86: Booting SMP configuration:
.... node #0, CPUs: #1
kvm-clock: cpu 1, msr 2:1fff8041, secondary cpu clock
smp: Brought up 1 node, 2 CPUs
smpboot: Max logical packages: 1
smpboot: Total of 2 processors activated (9200.00 BogoMIPS)
devtmpfs: initialized
kworker/u4:0 (24) used greatest stack depth: 24072 bytes left
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns
futex hash table entries: 512 (order: 4, 65536 bytes)
xor: automatically using best checksumming function avx
RTC time: 1:09:13, date: 07/05/18
NET: Registered protocol family 16
audit: initializing netlink subsys (disabled)
audit: type=2000 audit(1530752952.920:1): state=initialized audit_enabled=0 res=1
kworker/u4:1 (40) used greatest stack depth: 23840 bytes left
cpuidle: using governor menu
ACPI: bus type PCI registered
PCI: Using configuration type 1 for base access
kworker/u4:3 (167) used greatest stack depth: 21704 bytes left
HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages
cryptd: max_cpu_qlen set to 1000
raid6: sse2x1 gen() 1707 MB/s
raid6: sse2x1 xor() 1011 MB/s
raid6: sse2x2 gen() 3695 MB/s
raid6: sse2x2 xor() 1945 MB/s
raid6: sse2x4 gen() 6042 MB/s
raid6: sse2x4 xor() 3408 MB/s
raid6: avx2x1 gen() 968 MB/s
raid6: avx2x1 xor() 1904 MB/s
raid6: avx2x2 gen() 4250 MB/s
raid6: avx2x2 xor() 3867 MB/s
raid6: avx2x4 gen() 11429 MB/s
raid6: avx2x4 xor() 5939 MB/s
raid6: using algorithm avx2x4 gen() 11429 MB/s
raid6: .... xor() 5939 MB/s, rmw enabled
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: Added _OSI(Linux-Dell-Video)
ACPI: 2 ACPI AML tables successfully acquired and loaded
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: Enabled 16 GPEs in block 00 to 0F
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)
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 <giometti@xxxxxxxx>
PTP clock support registered
EDAC MC: Ver: 3.0.0
Advanced Linux Sound Architecture Driver Initialized.
PCI: Using ACPI for IRQ routing
Bluetooth: Core ver 2.22
NET: Registered protocol family 31
Bluetooth: HCI device and connection manager initialized
Bluetooth: HCI socket layer initialized
Bluetooth: L2CAP socket layer initialized
Bluetooth: SCO socket layer initialized
NET: Registered protocol family 8
NET: Registered protocol family 20
NetLabel: Initializing
NetLabel: domain hash size = 128
NetLabel: protocols = UNLABELED CIPSOv4 CALIPSO
NetLabel: unlabeled traffic allowed by default


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