linux_dsm_epyc7002/arch/s390/kvm
Igor Mammedov 13a17cc052 KVM: s390: kvm_s390_vm_start_migration: check dirty_bitmap before using it as target for memset()
If userspace doesn't set KVM_MEM_LOG_DIRTY_PAGES on memslot before calling
kvm_s390_vm_start_migration(), kernel will oops with:

  Unable to handle kernel pointer dereference in virtual kernel address space
  Failing address: 0000000000000000 TEID: 0000000000000483
  Fault in home space mode while using kernel ASCE.
  AS:0000000002a2000b R2:00000001bff8c00b R3:00000001bff88007 S:00000001bff91000 P:000000000000003d
  Oops: 0004 ilc:2 [#1] SMP
  ...
  Call Trace:
  ([<001fffff804ec552>] kvm_s390_vm_set_attr+0x347a/0x3828 [kvm])
   [<001fffff804ecfc0>] kvm_arch_vm_ioctl+0x6c0/0x1998 [kvm]
   [<001fffff804b67e4>] kvm_vm_ioctl+0x51c/0x11a8 [kvm]
   [<00000000008ba572>] do_vfs_ioctl+0x1d2/0xe58
   [<00000000008bb284>] ksys_ioctl+0x8c/0xb8
   [<00000000008bb2e2>] sys_ioctl+0x32/0x40
   [<000000000175552c>] system_call+0x2b8/0x2d8
  INFO: lockdep is turned off.
  Last Breaking-Event-Address:
   [<0000000000dbaf60>] __memset+0xc/0xa0

due to ms->dirty_bitmap being NULL, which might crash the host.

Make sure that ms->dirty_bitmap is set before using it or
return -EINVAL otherwise.

Cc: <stable@vger.kernel.org>
Fixes: afdad61615 ("KVM: s390: Fix storage attributes migration with memory slots")
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Link: https://lore.kernel.org/kvm/20190911075218.29153-1-imammedo@redhat.com/
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2019-09-12 13:09:17 +02:00
..
diag.c KVM: s390: add vcpu stat counters for many instruction 2018-01-24 16:49:02 +01:00
gaccess.c treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
gaccess.h KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
guestdbg.c KVM: s390: introduce defines for control registers 2018-05-17 09:02:27 +02:00
intercept.c KVM: s390: add exit io request stats and simplify code 2018-03-14 19:21:11 +00:00
interrupt.c KVM: s390: Use kvm_vcpu_wake_up in kvm_s390_vcpu_wakeup 2019-07-20 09:00:45 +02:00
irq.h KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
Kconfig * ARM: support for SVE and Pointer Authentication in guests, PMU improvements 2019-05-17 10:33:30 -07:00
kvm-s390.c KVM: s390: kvm_s390_vm_start_migration: check dirty_bitmap before using it as target for memset() 2019-09-12 13:09:17 +02:00
kvm-s390.h KVM: s390: add the GIB and its related life-cyle functions 2019-02-05 14:29:23 +01:00
Makefile KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
priv.c s390: ap: kvm: add PQAP interception for AQIC 2019-07-02 16:00:27 +02:00
sigp.c KVM: s390: introduce and use kvm_s390_test_cpuflags() 2018-01-24 17:46:42 +01:00
trace-s390.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vsie.c KVM: s390: vsie: Return correct values for Invalid CRYCB format 2019-04-29 09:01:22 +02:00