CVE-2020-8834

Priority
Description
KVM in the Linux kernel on Power8 processors has a conflicting use of
HSTATE_HOST_R1 to store r1 state in kvmppc_hv_entry plus in
kvmppc_{save,restore}_tm, leading to a stack corruption. Because of this,
an attacker with the ability run code in kernel space of a guest VM can
cause the host kernel to panic. There were two commits that, according to
the reporter, introduced the vulnerability: f024ee098476 ("KVM: PPC: Book3S
HV: Pull out TM state save/restore into separate procedures") 87a11bb6a7f7
("KVM: PPC: Book3S HV: Work around XER[SO] bug in fake suspend mode") The
former landed in 4.8, the latter in 4.17. This was fixed without realizing
the impact in 4.18 with the following three commits, though it's believed
the first is the only strictly necessary commit: 6f597c6b63b6 ("KVM: PPC:
Book3S PR: Add guest MSR parameter for
kvmppc_save_tm()/kvmppc_restore_tm()") 7b0e827c6970 ("KVM: PPC: Book3S HV:
Factor fake-suspend handling out of kvmppc_save/restore_tm") 009c872a8bc4
("KVM: PPC: Book3S PR: Move kvmppc_save_tm/kvmppc_restore_tm to separate
file")
Ubuntu-Description
Gustavo Romero and Paul Mackerras discovered that the KVM implementation in
the Linux kernel for PowerPC processors did not properly keep guest state
separate from host state. A local attacker in a KVM guest could use this to
cause a denial of service (host system crash).
Notes
sbeattieappears to only affect Power8 hardware and not Power9,
possibly because transaction memory in Power9 needs a software assist
to function.
from reporter, introduced in f024ee098476 and exacerbated by
87a11bb6a7f7.
sbeattieAddressed by: 7b0e827c6970e8ca77c60ae87592204c39e41245 KVM: PPC: Book3S HV: Factor fake-suspend handling out of kvmppc_save/restore_tm 009c872a8bc4d38f487a9bd62423d019e4322517 KVM: PPC: Book3S PR: Move kvmppc_save_tm/kvmppc_restore_tm to separate file 6f597c6b63b6f3675914b5ec8fcd008a58678650 KVM: PPC: Book3S PR: Add guest MSR parameter for kvmppc_save_tm()/kvmppc_restore_tm()
Package
Source: linux (LP Ubuntu Debian)
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):not-affected (v4.15 kernels only)
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (v4.15 kernels only)
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (v4.15 kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):released (4.15.0-96.97)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Patches:
Introduced by
f024ee098476a3e620232e4a78cfac505f121245
Fixed by
7b0e827c6970e8ca77c60ae87592204c39e41245
Introduced by
f024ee098476a3e620232e4a78cfac505f121245
Fixed by
009c872a8bc4d38f487a9bd62423d019e4322517
Introduced by
f024ee098476a3e620232e4a78cfac505f121245
Fixed by
6f597c6b63b6f3675914b5ec8fcd008a58678650
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (v4.15 kernels only)
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (v4.15 kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (ppc kernels only)
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.15.0-96.97~16.04.1)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):ignored (was needs-triage now end-of-life)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (v4.15 kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):not-affected (v4.15 kernels only)
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (v4.15 kernels only)
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (v4.15 kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (ppc kernels only)
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (v4.15 kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (v4.15 kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (v4.15 kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):not-affected (ppc kernels only)
Ubuntu 20.04 (Focal Fossa):not-affected (ppc kernels only)
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
Package
Upstream:released (4.18~rc1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (ppc kernels only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (ppc kernels only)
Ubuntu 19.10 (Eoan Ermine):DNE
Ubuntu 20.04 (Focal Fossa):DNE
More Information

Updated: 2020-04-22 14:15:36 UTC (commit 297513957a54517f8964384ba694e2c28c35eeca)