This series try to address CI failures for the pmtu.sh tests. It
does _not_ attempt to enable all the currently skipped cases, to
avoid adding more entropy.
Tested with:
make -C tools/testing/selftests/ TARGETS=net install
vng --build --config tools/testing/selftests/net/config
vng --run . --user root -- \
./tools/testing/selftests/kselftest_install/run_kselftest.sh \
-t net:pmtu.sh
Paolo Abeni (3):
selftests: net: add missing config for pmtu.sh tests
selftests: net: fix available tunnels detection
selftests: net: don't access /dev/stdout in pmtu.sh
tools/testing/selftests/net/config | 3 +++
tools/testing/selftests/net/pmtu.sh | 18 +++++++++---------
2 files changed, 12 insertions(+), 9 deletions(-)
--
2.43.0
This patch series give a proposal to support guest VM running
in user mode and in canonical linear address organization as
well.
First design to parition the 64-bit canonical linear address space
into two half parts belonging to user-mode and supervisor-mode
respectively, similar as the organization of linear addresses used
in linux OS. Currently the linear addresses use 48-bit canonical
format in which bits 63:47 of the address are identical.
Secondly setup page table mapping the same guest physical address
of test code and data segment onto both user-mode and supervisor-mode
address space. It allows guest in different runtime mode, i.e.
user or supervisor, can run one code base in the corresponding
linear address space.
Also provide the runtime environment setup API for switching to
user mode execution.
Zeng Guang (8):
KVM: selftests: x86: Fix bug in addr_arch_gva2gpa()
KVM: selftests: x86: Support guest running on canonical linear-address
organization
KVM: selftests: Add virt_arch_ucall_prealloc() arch specific
implementation
KVM : selftests : Adapt selftest cases to kernel canonical linear
address
KVM: selftests: x86: Prepare setup for user mode support
KVM: selftests: x86: Allow user to access user-mode address and I/O
address space
KVM: selftests: x86: Support vcpu run in user mode
KVM: selftests: x86: Add KVM forced emulation prefix capability
.../selftests/kvm/include/kvm_util_base.h | 20 ++-
.../selftests/kvm/include/x86_64/processor.h | 48 ++++++-
.../selftests/kvm/lib/aarch64/processor.c | 5 +
tools/testing/selftests/kvm/lib/kvm_util.c | 6 +-
.../selftests/kvm/lib/riscv/processor.c | 5 +
.../selftests/kvm/lib/s390x/processor.c | 5 +
.../testing/selftests/kvm/lib/ucall_common.c | 2 +
.../selftests/kvm/lib/x86_64/processor.c | 117 ++++++++++++++----
.../selftests/kvm/set_memory_region_test.c | 13 +-
.../testing/selftests/kvm/x86_64/debug_regs.c | 2 +-
.../kvm/x86_64/userspace_msr_exit_test.c | 9 +-
11 files changed, 195 insertions(+), 37 deletions(-)
--
2.21.3
l2_tos_ttl_inherit.sh verifies the inheritance of tos and ttl
for GRETAP, VXLAN and GENEVE.
Before testing it checks if the required module is available
and if not skips the tests accordingly.
Currently only GRETAP and VXLAN are tested because the GENEVE
module is missing.
Signed-off-by: Matthias May <matthias.may(a)westermo.com>
---
tools/testing/selftests/net/config | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config
index 19ff75051660..8d79c024bebf 100644
--- a/tools/testing/selftests/net/config
+++ b/tools/testing/selftests/net/config
@@ -76,6 +76,7 @@ CONFIG_CRYPTO_SM4_GENERIC=y
CONFIG_AMT=m
CONFIG_TUN=y
CONFIG_VXLAN=m
+CONFIG_GENEVE=m
CONFIG_IP_SCTP=m
CONFIG_NETFILTER_XT_MATCH_POLICY=m
CONFIG_CRYPTO_ARIA=y
--
2.39.2
From: Willem de Bruijn <willemb(a)google.com>
The test sends packets and compares enqueue, transmit and Ack
timestamps with expected values. It installs netem delays to increase
latency between these points.
The test proves flaky in virtual environment (vng). Increase the
delays to reduce variance. Scale measurement tolerance accordingly.
Time sensitive tests are difficult to calibrate. Increasing delays 10x
also increases runtime 10x, for one. And it may still prove flaky at
some rate.
Signed-off-by: Willem de Bruijn <willemb(a)google.com>
---
tools/testing/selftests/net/txtimestamp.sh | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/net/txtimestamp.sh b/tools/testing/selftests/net/txtimestamp.sh
index 31637769f59f..25baca4b148e 100755
--- a/tools/testing/selftests/net/txtimestamp.sh
+++ b/tools/testing/selftests/net/txtimestamp.sh
@@ -8,13 +8,13 @@ set -e
setup() {
# set 1ms delay on lo egress
- tc qdisc add dev lo root netem delay 1ms
+ tc qdisc add dev lo root netem delay 10ms
# set 2ms delay on ifb0 egress
modprobe ifb
ip link add ifb_netem0 type ifb
ip link set dev ifb_netem0 up
- tc qdisc add dev ifb_netem0 root netem delay 2ms
+ tc qdisc add dev ifb_netem0 root netem delay 20ms
# redirect lo ingress through ifb0 egress
tc qdisc add dev lo handle ffff: ingress
@@ -24,9 +24,11 @@ setup() {
}
run_test_v4v6() {
- # SND will be delayed 1000us
- # ACK will be delayed 6000us: 1 + 2 ms round-trip
- local -r args="$@ -v 1000 -V 6000"
+ # SND will be delayed 10ms
+ # ACK will be delayed 60ms: 10 + 20 ms round-trip
+ # allow +/- tolerance of 8ms
+ # wait for ACK to be queued
+ local -r args="$@ -v 10000 -V 60000 -t 8000 -S 80000"
./txtimestamp ${args} -4 -L 127.0.0.1
./txtimestamp ${args} -6 -L ::1
--
2.43.0.429.g432eaa2c6b-goog
From: Jeff Xu <jeffxu(a)chromium.org>
This patchset proposes a new mseal() syscall for the Linux kernel.
In a nutshell, mseal() protects the VMAs of a given virtual memory
range against modifications, such as changes to their permission bits.
Modern CPUs support memory permissions, such as the read/write (RW)
and no-execute (NX) bits. Linux has supported NX since the release of
kernel version 2.6.8 in August 2004 [1]. The memory permission feature
improves the security stance on memory corruption bugs, as an attacker
cannot simply write to arbitrary memory and point the code to it. The
memory must be marked with the X bit, or else an exception will occur.
Internally, the kernel maintains the memory permissions in a data
structure called VMA (vm_area_struct). mseal() additionally protects
the VMA itself against modifications of the selected seal type.
Memory sealing is useful to mitigate memory corruption issues where a
corrupted pointer is passed to a memory management system. For
example, such an attacker primitive can break control-flow integrity
guarantees since read-only memory that is supposed to be trusted can
become writable or .text pages can get remapped. Memory sealing can
automatically be applied by the runtime loader to seal .text and
.rodata pages and applications can additionally seal security critical
data at runtime. A similar feature already exists in the XNU kernel
with the VM_FLAGS_PERMANENT [3] flag and on OpenBSD with the
mimmutable syscall [4]. Also, Chrome wants to adopt this feature for
their CFI work [2] and this patchset has been designed to be
compatible with the Chrome use case.
Two system calls are involved in sealing the map: mmap() and mseal().
The new mseal() is an syscall on 64 bit CPU, and with
following signature:
int mseal(void addr, size_t len, unsigned long flags)
addr/len: memory range.
flags: reserved.
mseal() blocks following operations for the given memory range.
1> Unmapping, moving to another location, and shrinking the size,
via munmap() and mremap(), can leave an empty space, therefore can
be replaced with a VMA with a new set of attributes.
2> Moving or expanding a different VMA into the current location,
via mremap().
3> Modifying a VMA via mmap(MAP_FIXED).
4> Size expansion, via mremap(), does not appear to pose any specific
risks to sealed VMAs. It is included anyway because the use case is
unclear. In any case, users can rely on merging to expand a sealed VMA.
5> mprotect() and pkey_mprotect().
6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous
memory, when users don't have write permission to the memory. Those
behaviors can alter region contents by discarding pages, effectively a
memset(0) for anonymous memory.
In addition: mmap() has two related changes.
The PROT_SEAL bit in prot field of mmap(). When present, it marks
the map sealed since creation.
The MAP_SEALABLE bit in the flags field of mmap(). When present, it marks
the map as sealable. A map created without MAP_SEALABLE will not support
sealing, i.e. mseal() will fail.
Applications that don't care about sealing will expect their behavior
unchanged. For those that need sealing support, opt-in by adding
MAP_SEALABLE in mmap().
The idea that inspired this patch comes from Stephen Röttger’s work in
V8 CFI [5]. Chrome browser in ChromeOS will be the first user of this
API.
Indeed, the Chrome browser has very specific requirements for sealing,
which are distinct from those of most applications. For example, in
the case of libc, sealing is only applied to read-only (RO) or
read-execute (RX) memory segments (such as .text and .RELRO) to
prevent them from becoming writable, the lifetime of those mappings
are tied to the lifetime of the process.
Chrome wants to seal two large address space reservations that are
managed by different allocators. The memory is mapped RW- and RWX
respectively but write access to it is restricted using pkeys (or in
the future ARM permission overlay extensions). The lifetime of those
mappings are not tied to the lifetime of the process, therefore, while
the memory is sealed, the allocators still need to free or discard the
unused memory. For example, with madvise(DONTNEED).
However, always allowing madvise(DONTNEED) on this range poses a
security risk. For example if a jump instruction crosses a page
boundary and the second page gets discarded, it will overwrite the
target bytes with zeros and change the control flow. Checking
write-permission before the discard operation allows us to control
when the operation is valid. In this case, the madvise will only
succeed if the executing thread has PKEY write permissions and PKRU
changes are protected in software by control-flow integrity.
Although the initial version of this patch series is targeting the
Chrome browser as its first user, it became evident during upstream
discussions that we would also want to ensure that the patch set
eventually is a complete solution for memory sealing and compatible
with other use cases. The specific scenario currently in mind is
glibc's use case of loading and sealing ELF executables. To this end,
Stephen is working on a change to glibc to add sealing support to the
dynamic linker, which will seal all non-writable segments at startup.
Once this work is completed, all applications will be able to
automatically benefit from these new protections.
In closing, I would like to formally acknowledge the valuable
contributions received during the RFC process, which were instrumental
in shaping this patch:
Jann Horn: raising awareness and providing valuable insights on the
destructive madvise operations.
Linus Torvalds: assisting in defining system call signature and scope.
Pedro Falcato: suggesting sealing in the mmap().
Theo de Raadt: sharing the experiences and insights gained from
implementing mimmutable() in OpenBSD.
Change history:
===============
V7:
- fix index.rst (Randy Dunlap)
- fix arm build (Randy Dunlap)
- return EPERM for blocked operations (Theo de Raadt)
V6:
- Drop RFC from subject, Given Linus's general approval.
- Adjust syscall number for mseal (main Jan.11/2024)
- Code style fix (Matthew Wilcox)
- selftest: use ksft macros (Muhammad Usama Anjum)
- Document fix. (Randy Dunlap)
https://lore.kernel.org/all/20240111234142.2944934-1-jeffxu@chromium.org/
V5:
- fix build issue in mseal-Wire-up-mseal-syscall
(Suggested by Linus Torvalds, and Greg KH)
- updates on selftest.
https://lore.kernel.org/lkml/20240109154547.1839886-1-jeffxu@chromium.org/#r
V4:
(Suggested by Linus Torvalds)
- new signature: mseal(start,len,flags)
- 32 bit is not supported. vm_seal is removed, use vm_flags instead.
- single bit in vm_flags for sealed state.
- CONFIG_MSEAL kernel config is removed.
- single bit of PROT_SEAL in the "Prot" field of mmap().
Other changes:
- update selftest (Suggested by Muhammad Usama Anjum)
- update documentation.
https://lore.kernel.org/all/20240104185138.169307-1-jeffxu@chromium.org/
V3:
- Abandon per-syscall approach, (Suggested by Linus Torvalds).
- Organize sealing types around their functionality, such as
MM_SEAL_BASE, MM_SEAL_PROT_PKEY.
- Extend the scope of sealing from calls originated in userspace to
both kernel and userspace. (Suggested by Linus Torvalds)
- Add seal type support in mmap(). (Suggested by Pedro Falcato)
- Add a new sealing type: MM_SEAL_DISCARD_RO_ANON to prevent
destructive operations of madvise. (Suggested by Jann Horn and
Stephen Röttger)
- Make sealed VMAs mergeable. (Suggested by Jann Horn)
- Add MAP_SEALABLE to mmap()
- Add documentation - mseal.rst
https://lore.kernel.org/linux-mm/20231212231706.2680890-2-jeffxu@chromium.o…
v2:
Use _BITUL to define MM_SEAL_XX type.
Use unsigned long for seal type in sys_mseal() and other functions.
Remove internal VM_SEAL_XX type and convert_user_seal_type().
Remove MM_ACTION_XX type.
Remove caller_origin(ON_BEHALF_OF_XX) and replace with sealing bitmask.
Add more comments in code.
Add a detailed commit message.
https://lore.kernel.org/lkml/20231017090815.1067790-1-jeffxu@chromium.org/
v1:
https://lore.kernel.org/lkml/20231016143828.647848-1-jeffxu@chromium.org/
----------------------------------------------------------------
[1] https://kernelnewbies.org/Linux_2_6_8
[2] https://v8.dev/blog/control-flow-integrity
[3] https://github.com/apple-oss-distributions/xnu/blob/1031c584a5e37aff177559b…
[4] https://man.openbsd.org/mimmutable.2
[5] https://docs.google.com/document/d/1O2jwK4dxI3nRcOJuPYkonhTkNQfbmwdvxQMyXge…
[6] https://lore.kernel.org/lkml/CAG48ez3ShUYey+ZAFsU2i1RpQn0a5eOs2hzQ426Fkcgnf…
[7] https://lore.kernel.org/lkml/20230515130553.2311248-1-jeffxu@chromium.org/
Jeff Xu (4):
mseal: Wire up mseal syscall
mseal: add mseal syscall
selftest mm/mseal memory sealing
mseal:add documentation
Documentation/userspace-api/index.rst | 1 +
Documentation/userspace-api/mseal.rst | 183 ++
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 2 +
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n64.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
include/linux/mm.h | 48 +
include/linux/syscalls.h | 1 +
include/uapi/asm-generic/mman-common.h | 8 +
include/uapi/asm-generic/unistd.h | 5 +-
kernel/sys_ni.c | 1 +
mm/Makefile | 4 +
mm/madvise.c | 12 +
mm/mmap.c | 27 +
mm/mprotect.c | 10 +
mm/mremap.c | 31 +
mm/mseal.c | 343 ++++
tools/testing/selftests/mm/.gitignore | 1 +
tools/testing/selftests/mm/Makefile | 1 +
tools/testing/selftests/mm/mseal_test.c | 1997 +++++++++++++++++++
33 files changed, 2690 insertions(+), 2 deletions(-)
create mode 100644 Documentation/userspace-api/mseal.rst
create mode 100644 mm/mseal.c
create mode 100644 tools/testing/selftests/mm/mseal_test.c
--
2.43.0.429.g432eaa2c6b-goog