linux_dsm_epyc7002/arch/s390
Christian Borntraeger 0447819741 KVM: s390: do not expose random data via facility bitmap
kvm_s390_get_machine() populates the facility bitmap by copying bytes
from the host results that are stored in a 256 byte array in the prefix
page. The KVM code does use the size of the target buffer (2k), thus
copying and exposing unrelated kernel memory (mostly machine check
related logout data).

Let's use the size of the source buffer instead.  This is ok, as the
target buffer will always be greater or equal than the source buffer as
the KVM internal buffers (and thus S390_ARCH_FAC_LIST_SIZE_BYTE) cover
the maximum possible size that is allowed by STFLE, which is 256
doublewords. All structures are zero allocated so we can leave bytes
256-2047 unchanged.

Add a similar fix for kvm_arch_init_vm().

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[found with smatch]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: stable@vger.kernel.org
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-20 15:29:34 +01:00
..
appldata Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
boot Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
configs s390: update defconfig 2016-11-23 16:02:24 +01:00
crypto Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
hypfs s390: hypfs: make inode explicitly non-modular 2016-10-31 17:55:40 +01:00
include Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2017-01-02 09:08:45 -08:00
kernel Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2017-01-02 09:08:45 -08:00
kvm KVM: s390: do not expose random data via facility bitmap 2017-01-20 15:29:34 +01:00
lib s390/lib: add missing memory barriers to string inline assemblies 2016-12-14 16:33:41 +01:00
mm Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
net bpf: xdp: Allow head adjustment in XDP prog 2016-12-08 14:25:13 -05:00
numa s390/numa: pin all possible cpus to nodes early 2016-12-07 07:23:33 +01:00
oprofile s390/dumpstack: restore reliable indicator for call traces 2016-10-17 14:44:30 +02:00
pci s390/pci: query fmb length 2016-12-14 16:33:41 +01:00
tools s390: remove unneeded dependency for gen_facilities 2016-11-08 10:30:28 +01:00
defconfig mm/usercopy: get rid of CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2016-08-30 10:10:21 -07:00
Kbuild s390/numa: add core infrastructure 2015-08-03 18:40:25 +02:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2016-12-13 16:33:33 -08:00
Kconfig.debug arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug 2016-01-09 06:30:49 -08:00
Makefile s390: add assembler include path for vx-insn.h 2016-09-06 11:00:04 +02:00