linux/arch/x86/kvm
Wanpeng Li 9a11997e75 KVM: X86: Fix dereference null cpufreq policy
Naresh Kamboju reported:

   Linux version 5.6.0-rc4 (oe-user@oe-host) (gcc version
  (GCC)) #1 SMP Sun Mar 1 22:59:08 UTC 2020
   kvm: no hardware support
   BUG: kernel NULL pointer dereference, address: 000000000000028c
   #PF: supervisor read access in kernel mode
   #PF: error_code(0x0000) - not-present page
   PGD 0 P4D 0
   Oops: 0000 [#1] SMP NOPTI
   CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4 #1
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
  04/01/2014
   RIP: 0010:kobject_put+0x12/0x1c0
   Call Trace:
    cpufreq_cpu_put+0x15/0x20
    kvm_arch_init+0x1f6/0x2b0
    kvm_init+0x31/0x290
    ? svm_check_processor_compat+0xd/0xd
    ? svm_check_processor_compat+0xd/0xd
    svm_init+0x21/0x23
    do_one_initcall+0x61/0x2f0
    ? rdinit_setup+0x30/0x30
    ? rcu_read_lock_sched_held+0x4f/0x80
    kernel_init_freeable+0x219/0x279
    ? rest_init+0x250/0x250
    kernel_init+0xe/0x110
    ret_from_fork+0x27/0x50
   Modules linked in:
   CR2: 000000000000028c
   ---[ end trace 239abf40c55c409b ]---
   RIP: 0010:kobject_put+0x12/0x1c0

cpufreq policy which is get by cpufreq_cpu_get() can be NULL if it is failure,
this patch takes care of it.

Fixes: aaec7c03de (KVM: x86: avoid useless copy of cpufreq policy)
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-02 17:06:52 +01:00
..
mmu KVM: x86/mmu: Fix struct guest_walker arrays for 5-level paging 2020-02-12 20:09:44 +01:00
vmx KVM: VMX: check descriptor table exits on instruction emulation 2020-03-01 19:26:31 +01:00
cpuid.c kvm/svm: PKU not currently supported 2020-01-27 19:59:35 +01:00
cpuid.h KVM: x86: Refactor and rename bit() to feature_bit() macro 2020-01-21 14:45:28 +01:00
debugfs.c KVM: no need to check return value of debugfs_create functions 2019-08-05 12:55:49 +02:00
emulate.c kvm/emulate: fix a -Werror=cast-function-type 2020-02-20 18:13:45 +01:00
hyperv.c kvm: x86: hyperv: Use APICv update request interface 2020-02-05 15:17:43 +01:00
hyperv.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
i8254.c kvm: i8254: Deactivate APICv when using in-kernel PIT re-injection mode. 2020-02-05 15:17:44 +01:00
i8254.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
i8259.c KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF attacks 2020-01-27 19:59:37 +01:00
ioapic.c kvm: ioapic: Lazy update IOAPIC EOI 2020-02-05 15:17:44 +01:00
ioapic.h KVM: X86: Move irrelevant declarations out of ioapic.h 2020-01-08 17:33:14 +01:00
irq_comm.c KVM: x86: don't notify userspace IOAPIC on edge-triggered interrupt EOI 2020-02-21 18:04:57 +01:00
irq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 320 2019-06-05 17:37:05 +02:00
irq.h KVM: X86: Move irrelevant declarations out of ioapic.h 2020-01-08 17:33:14 +01:00
Kconfig KVM: allow disabling -Werror 2020-02-28 10:45:28 +01:00
kvm_cache_regs.h KVM: x86: Fold decache_cr3() into cache_reg() 2019-10-22 13:34:16 +02:00
lapic.c KVM: apic: avoid calculating pending eoi from an uninitialized val 2020-02-21 18:05:44 +01:00
lapic.h kvm: lapic: Introduce APICv update helper function 2020-02-05 15:17:40 +01:00
Makefile KVM: allow disabling -Werror 2020-02-28 10:45:28 +01:00
mmu_audit.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
mmu.h KVM: x86/mmu: Avoid retpoline on ->page_fault() with TDP 2020-02-12 20:09:42 +01:00
mmutrace.h KVM: x86: fix incorrect comparison in trace event 2020-02-20 18:13:44 +01:00
mtrr.c KVM: x86: Protect MSR-based index computations in fixed_msr_to_seg_unit() from Spectre-v1/L1TF attacks 2020-01-27 19:59:39 +01:00
pmu_amd.c KVM: x86/vPMU: Add lazy mechanism to release perf_event per vPMC 2019-11-15 11:44:10 +01:00
pmu.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 15:42:43 -08:00
pmu.h KVM: x86: Protect MSR-based index computations in pmu.h from Spectre-v1/L1TF attacks 2020-01-27 19:59:40 +01:00
svm.c KVM: x86: allow compiling as non-module with W=1 2020-02-28 10:35:37 +01:00
trace.h kvm: x86: Add APICv (de)activate request trace points 2020-02-05 15:17:41 +01:00
tss.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
x86.c KVM: X86: Fix dereference null cpufreq policy 2020-03-02 17:06:52 +01:00
x86.h KVM: x86: Take a u64 when checking for a valid dr7 value 2020-02-05 15:17:45 +01:00