linux-kernel - [PATCH 00/14] UBSan Enablement for hyp/nVHE code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200914172750.852684-1-georgepope@google.com>
Date:   Mon, 14 Sep 2020 17:27:36 +0000
From:   George-Aurelian Popescu <georgepope@...gle.com>
To:     maz@...nel.org, catalin.marinas@....com, will@...nel.org,
        masahiroy@...nel.org, michal.lkml@...kovi.net
Cc:     linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.cs.columbia.edu,
        linux-kernel@...r.kernel.org, linux-kbuild@...r.kernel.org,
        clang-built-linux@...glegroups.com, james.morse@....com,
        julien.thierry.kdev@...il.com, suzuki.poulose@....com,
        natechancellor@...il.com, ndesaulniers@...gle.com,
        dbrazdil@...gle.com, broonie@...nel.org, maskray@...gle.com,
        ascull@...gle.com, keescook@...omium.org,
        akpm@...ux-foundation.org, dvyukov@...gle.com, elver@...gle.com,
        tglx@...utronix.de, arnd@...db.de,
        George-Aurelian Popescu <georgepope@...gle.com>
Subject: [PATCH 00/14] UBSan Enablement for hyp/nVHE code

The main problem solved is logging from hyp/nVHE. Because the nVHE code is
independent from the Linux kernel the logging mechanisms aren’t working.
For this purpose a generic kvm_debug_buffer is designed. It is composed
from a statically allocated array and a writing index and comes with a set
of macros to facilitate it’s usage. To avoid concurrency problems between
cores, the kvm_debug_buffer is defined per_cpu. The buffer is checked every
time when the code returns from an hvc call, by modifying the kvm_call_hyp
and kvm_call_hyp_ret macros. The buffer’s writing index is reseted to zero
inside of the el1_sync entry.

Since UBSan’s handlers are living inside the kernel, they can not be called
inside hyp/nVHE. To enable UBSan new handlers had to be defined there. To
store the data from the handler, the kvm_ubsan_buff is defined. It can store
logging data from the handlers in a new defined struct called struct
kvm_ubsan_info. Each handler has to encapsulate it’s data inside the new
struct and write it into the buffer. The kvm_debug_buffer.c file is
responsible for decapsulating the data and calling the kernel handlers.
To check if UBSan works correctly inside hyp/nVHE the last patch comes
with a test mechanism, that calls UBSan when the hyp is initialized.


George Popescu (14):
  KVM: arm64: Enable UBSan instrumentation in nVHE hyp code
  KVM: arm64: Define a macro for storing a value inside a per_cpu
    variable
  KVM: arm64: Add support for creating and checking a logging buffer
    inside hyp/nVHE
  KVM: arm64: Add support for buffer usage
  KVM: arm64: Define a buffer that can pass UBSan data from hyp/nVHE to
    kernel
  Fix CFLAGS for UBSAN_BOUNDS on Clang
  KVM: arm64: Enable UBSAN_BOUNDS for the both the kernel and hyp/nVHE
  KVM: arm64: Enable UBsan check for unreachable code inside hyp/nVHE
    code
  KVM: arm64: Enable shift out of bounds undefined behaviour check for
    hyp/nVHE
  KVM: arm64: __ubsan_handle_load_invalid_value hyp/nVHE implementation.
  KVM: arm64: Detect type mismatch undefined behaviour from hyp/nVHE
    code
  KVM: arm64: Detect arithmetic overflow is inside hyp/nVHE.
  KVM: arm64: Enable the CONFIG_TEST UBSan for PKVM.
  DO NOT MERGE: Enable configs to test the patch series

 arch/arm64/include/asm/kvm_asm.h          |   8 ++
 arch/arm64/include/asm/kvm_debug_buffer.h |  61 ++++++++
 arch/arm64/include/asm/kvm_host.h         |  12 ++
 arch/arm64/include/asm/kvm_ubsan.h        |  53 +++++++
 arch/arm64/kvm/Kconfig                    |   3 +
 arch/arm64/kvm/Makefile                   |   4 +
 arch/arm64/kvm/arm.c                      |  46 +++++-
 arch/arm64/kvm/hyp/hyp-entry.S            |   6 +-
 arch/arm64/kvm/hyp/nvhe/Makefile          |   5 +-
 arch/arm64/kvm/hyp/nvhe/ubsan.c           | 164 ++++++++++++++++++++++
 arch/arm64/kvm/hyp/nvhe/ubsan_test.c      | 115 +++++++++++++++
 arch/arm64/kvm/kvm_ubsan_buffer.c         |  75 ++++++++++
 lib/Kconfig.ubsan                         |   5 +-
 scripts/Makefile.ubsan                    |   9 +-
 14 files changed, 561 insertions(+), 5 deletions(-)
 create mode 100644 arch/arm64/include/asm/kvm_debug_buffer.h
 create mode 100644 arch/arm64/include/asm/kvm_ubsan.h
 create mode 100644 arch/arm64/kvm/hyp/nvhe/ubsan.c
 create mode 100644 arch/arm64/kvm/hyp/nvhe/ubsan_test.c
 create mode 100644 arch/arm64/kvm/kvm_ubsan_buffer.c

-- 
2.28.0.618.gf4bc123cb7-goog