KVM x86 CET virtualization support for 6.18
Add support for virtualizing Control-flow Enforcement Technology (CET) on
Intel (Shadow Stacks and Indirect Branch Tracking) and AMD (Shadow Stacks).
CET is comprised of two distinct features, Shadow Stacks (SHSTK) and Indirect
Branch Tracking (IBT), that can be utilized by software to help provide
Control-flow integrity (CFI). SHSTK defends against backward-edge attacks
(a.k.a. Return-oriented programming (ROP)), while IBT defends against
forward-edge attacks (a.k.a. similarly CALL/JMP-oriented programming (COP/JOP)).
Attackers commonly use ROP and COP/JOP methodologies to redirect the control-
flow to unauthorized targets in order to execute small snippets of code,
a.k.a. gadgets, of the attackers choice. By chaining together several gadgets,
an attacker can perform arbitrary operations and circumvent the system's
defenses.
SHSTK defends against backward-edge attacks, which execute gadgets by modifying
the stack to branch to the attacker's target via RET, by providing a second
stack that is used exclusively to track control transfer operations. The
shadow stack is separate from the data/normal stack, and can be enabled
independently in user and kernel mode.
When SHSTK is is enabled, CALL instructions push the return address on both the
data and shadow stack. RET then pops the return address from both stacks and
compares the addresses. If the return addresses from the two stacks do not
match, the CPU generates a Control Protection (#CP) exception.
IBT defends against backward-edge attacks, which branch to gadgets by executing
indirect CALL and JMP instructions with attacker controlled register or memory
state, by requiring the target of indirect branches to start with a special
marker instruction, ENDBRANCH. If an indirect branch is executed and the next
instruction is not an ENDBRANCH, the CPU generates a #CP. Note, ENDBRANCH
behaves as a NOP if IBT is disabled or unsupported.
From a virtualization perspective, CET presents several problems. While SHSTK
and IBT have two layers of enabling, a global control in the form of a CR4 bit,
and a per-feature control in user and kernel (supervisor) MSRs (U_CET and S_CET
respectively), the {S,U}_CET MSRs can be context switched via XSAVES/XRSTORS.
Practically speaking, intercepting and emulating XSAVES/XRSTORS is not a viable
option due to complexity, and outright disallowing use of XSTATE to context
switch SHSTK/IBT state would render the features unusable to most guests.
To limit the overall complexity without sacrificing performance or usability,
simply ignore the potential virtualization hole, but ensure that all paths in
KVM treat SHSTK/IBT as usable by the guest if the feature is supported in
hardware, and the guest has access to at least one of SHSTK or IBT. I.e. allow
userspace to advertise one of SHSTK or IBT if both are supported in hardware,
even though doing so would allow a misbehaving guest to use the unadvertised
feature.
Fully emulating SHSTK and IBT would also require significant complexity, e.g.
to track and update branch state for IBT, and shadow stack state for SHSTK.
Given that emulating large swaths of the guest code stream isn't necessary on
modern CPUs, punt on emulating instructions that meaningful impact or consume
SHSTK or IBT. However, instead of doing nothing, explicitly reject emulation
of such instructions so that KVM's emulator can't be abused to circumvent CET.
Disable support for SHSTK and IBT if KVM is configured such that emulation of
arbitrary guest instructions may be required, specifically if Unrestricted
Guest (Intel only) is disabled, or if KVM will emulate a guest.MAXPHYADDR that
is smaller than host.MAXPHYADDR.
Lastly disable SHSTK support if shadow paging is enabled, as the protections
for the shadow stack are novel (shadow stacks require Writable=0,Dirty=1, so
that they can't be directly modified by software), i.e. would require
non-trivial support in the Shadow MMU.
Note, AMD CPUs currently only support SHSTK. Explicitly disable IBT support
so that KVM doesn't over-advertise if AMD CPUs add IBT, and virtualizing IBT
in SVM requires KVM modifications.
KVM x86 changes for 6.18
- Don't (re)check L1 intercepts when completing userspace I/O to fix a flaw
where a misbehaving usersepace (a.k.a. syzkaller) could swizzle L1's
intercepts and trigger a variety of WARNs in KVM.
- Emulate PERF_CNTR_GLOBAL_STATUS_SET for PerfMonV2 guests, as the MSR is
supposed to exist for v2 PMUs.
- Allow Centaur CPU leaves (base 0xC000_0000) for Zhaoxin CPUs.
- Clean up KVM's vector hashing code for delivering lowest priority IRQs.
- Clean up the fastpath handler code to only handle IPIs and WRMSRs that are
actually "fast", as opposed to handling those that KVM _hopes_ are fast, and
in the process of doing so add fastpath support for TSC_DEADLINE writes on
AMD CPUs.
- Clean up a pile of PMU code in anticipation of adding support for mediated
vPMUs.
- Add support for the immediate forms of RDMSR and WRMSRNS, sans full
emulator support (KVM should never need to emulate the MSRs outside of
forced emulation and other contrived testing scenarios).
- Clean up the MSR APIs in preparation for CET and FRED virtualization, as
well as mediated vPMU support.
- Rejecting a fully in-kernel IRQCHIP if EOIs are protected, i.e. for TDX VMs,
as KVM can't faithfully emulate an I/O APIC for such guests.
- KVM_REQ_MSR_FILTER_CHANGED into a generic RECALC_INTERCEPTS in preparation
for mediated vPMU support, as KVM will need to recalculate MSR intercepts in
response to PMU refreshes for guests with mediated vPMUs.
- Misc cleanups and minor fixes.
KVM selftests changes for 6.18
- Add #DE coverage in the fastops test (the only exception that's guest-
triggerable in fastop-emulated instructions).
- Fix PMU selftests errors encountered on Granite Rapids (GNR), Sierra
Forest (SRF) and Clearwater Forest (CWF).
- Minor cleanups and improvements
KVM/riscv changes for 6.18
- Added SBI FWFT extension for Guest/VM with misaligned
delegation and pointer masking PMLEN features
- Added ONE_REG interface for SBI FWFT extension
- Added Zicbop and bfloat16 extensions for Guest/VM
- Enabled more common KVM selftests for RISC-V such as
access_tracking_perf_test, dirty_log_perf_test,
memslot_modification_stress_test, memslot_perf_test,
mmu_stress_test, and rseq_test
- Added SBI v3.0 PMU enhancements in KVM and perf driver
KVM/arm64 updates for 6.18
- Add support for FF-A 1.2 as the secure memory conduit for pKVM,
allowing more registers to be used as part of the message payload.
- Change the way pKVM allocates its VM handles, making sure that the
privileged hypervisor is never tricked into using uninitialised
data.
- Speed up MMIO range registration by avoiding unnecessary RCU
synchronisation, which results in VMs starting much quicker.
- Add the dump of the instruction stream when panic-ing in the EL2
payload, just like the rest of the kernel has always done. This will
hopefully help debugging non-VHE setups.
- Add 52bit PA support to the stage-1 page-table walker, and make use
of it to populate the fault level reported to the guest on failing
to translate a stage-1 walk.
- Add NV support to the GICv3-on-GICv5 emulation code, ensuring
feature parity for guests, irrespective of the host platform.
- Fix some really ugly architecture problems when dealing with debug
in a nested VM. This has some bad performance impacts, but is at
least correct.
- Add enough infrastructure to be able to disable EL2 features and
give effective values to the EL2 control registers. This then allows
a bunch of features to be turned off, which helps cross-host
migration.
- Large rework of the selftest infrastructure to allow most tests to
transparently run at EL2. This is the first step towards enabling
NV testing.
- Various fixes and improvements all over the map, including one BE
fix, just in time for the removal of the feature.
KVM/arm64 changes for 6.17, round #3
- Invalidate nested MMUs upon freeing the PGD to avoid WARNs when
visiting from an MMU notifier
- Fixes to the TLB match process and TLB invalidation range for
managing the VCNR pseudo-TLB
- Prevent SPE from erroneously profiling guests due to UNKNOWN reset
values in PMSCR_EL1
- Fix save/restore of host MDCR_EL2 to account for eagerly programming
at vcpu_load() on VHE systems
- Correct lock ordering when dealing with VGIC LPIs, avoiding scenarios
where an xarray's spinlock was nested with a *raw* spinlock
- Permit stage-2 read permission aborts which are possible in the case
of NV depending on the guest hypervisor's stage-2 translation
- Call raw_spin_unlock() instead of the internal spinlock API
- Fix parameter ordering when assigning VBAR_EL1
[Pull into kvm/master to fix conflicts. - Paolo]
Pull cgroup updates from Tejun Heo:
- Extensive cpuset code cleanup and refactoring work with no functional
changes: CPU mask computation logic refactoring, introducing new
helpers, removing redundant code paths, and improving error handling
for better maintainability.
- A few bug fixes to cpuset including fixes for partition creation
failures when isolcpus is in use, missing error returns, and null
pointer access prevention in free_tmpmasks().
- Core cgroup changes include replacing the global percpu_rwsem with
per-threadgroup rwsem when writing to cgroup.procs for better
scalability, workqueue conversions to use WQ_PERCPU and
system_percpu_wq to prepare for workqueue default switching from
percpu to unbound, and removal of unused code including the
post_attach callback.
- New cgroup.stat.local time accounting feature that tracks frozen time
duration.
- Misc changes including selftests updates (new freezer time tests and
backward compatibility fixes), documentation sync, string function
safety improvements, and 64-bit division fixes.
* tag 'cgroup-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (39 commits)
cpuset: remove is_prs_invalid helper
cpuset: remove impossible warning in update_parent_effective_cpumask
cpuset: remove redundant special case for null input in node mask update
cpuset: fix missing error return in update_cpumask
cpuset: Use new excpus for nocpu error check when enabling root partition
cpuset: fix failure to enable isolated partition when containing isolcpus
Documentation: cgroup-v2: Sync manual toctree
cpuset: use partition_cpus_change for setting exclusive cpus
cpuset: use parse_cpulist for setting cpus.exclusive
cpuset: introduce partition_cpus_change
cpuset: refactor cpus_allowed_validate_change
cpuset: refactor out validate_partition
cpuset: introduce cpus_excl_conflict and mems_excl_conflict helpers
cpuset: refactor CPU mask buffer parsing logic
cpuset: Refactor exclusive CPU mask computation logic
cpuset: change return type of is_partition_[in]valid to bool
cpuset: remove unused assignment to trialcs->partition_root_state
cpuset: move the root cpuset write check earlier
cgroup/cpuset: Remove redundant rcu_read_lock/unlock() in spin_lock
cgroup: Remove redundant rcu_read_lock/unlock() in spin_lock
...
Add basic tests for sending data over PSP and making sure that key
rotation toggles the MSB of the spi.
Deploy PSP responder on the remote end. We also need a healthy dose
of common helpers for setting up the connections, assertions and
interrogating socket state on the Python side.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250927225420.1443468-5-kuba@kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
PSP tests need the remote system to support PSP, and some PSP capable
application to exchange data with. Create a simple PSP responder app
which we can build and deploy to the remote host. The tests themselves
can be written in Python but for ease of deploying the responder is in C
(using C YNL).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250927225420.1443468-4-kuba@kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This introduces a test for IPSec offload over bonding, utilizing netdevsim
for the testing process, as veth interfaces do not support IPSec offload.
The test will ensure that the IPSec offload functionality remains operational
even after a failover event occurs in the bonding configuration.
Here is the test result:
TEST: bond_ipsec_offload (active_slave eth0) [ OK ]
TEST: bond_ipsec_offload (active_slave eth1) [ OK ]
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20250925023304.472186-2-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Pull powerpc updates from Madhavan Srinivasan:
- powerpc support for BPF arena and arena atomics
- Patches to switch to msi parent domain (per-device MSI domains)
- Add a lock contention tracepoint in the queued spinlock slowpath
- Fixes for underflow in pseries/powernv msi and pci paths
- Switch from legacy-of-mm-gpiochip dependency to platform driver
- Fixes for handling TLB misses
- Introduce support for powerpc papr-hvpipe
- Add vpa-dtl PMU driver for pseries platform
- Misc fixes and cleanups
Thanks to Aboorva Devarajan, Aditya Bodkhe, Andrew Donnellan, Athira
Rajeev, Cédric Le Goater, Christophe Leroy, Erhard Furtner, Gautam
Menghani, Geert Uytterhoeven, Haren Myneni, Hari Bathini, Joe Lawrence,
Kajol Jain, Kienan Stewart, Linus Walleij, Mahesh Salgaonkar, Nam Cao,
Nicolas Schier, Nysal Jan K.A., Ritesh Harjani (IBM), Ruben Wauters,
Saket Kumar Bhaskar, Shashank MS, Shrikanth Hegde, Tejas Manhas, Thomas
Gleixner, Thomas Huth, Thorsten Blum, Tyrel Datwyler, and Venkat Rao
Bagalkote.
* tag 'powerpc-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (49 commits)
powerpc/pseries: Define __u{8,32} types in papr_hvpipe_hdr struct
genirq/msi: Remove msi_post_free()
powerpc/perf/vpa-dtl: Add documentation for VPA dispatch trace log PMU
powerpc/perf/vpa-dtl: Handle the writing of perf record when aux wake up is needed
powerpc/perf/vpa-dtl: Add support to capture DTL data in aux buffer
powerpc/perf/vpa-dtl: Add support to setup and free aux buffer for capturing DTL data
docs: ABI: sysfs-bus-event_source-devices-vpa-dtl: Document sysfs event format entries for vpa_dtl pmu
powerpc/vpa_dtl: Add interface to expose vpa dtl counters via perf
powerpc/time: Expose boot_tb via accessor
powerpc/32: Remove PAGE_KERNEL_TEXT to fix startup failure
powerpc/fprobe: fix updated fprobe for function-graph tracer
powerpc/ftrace: support CONFIG_FUNCTION_GRAPH_RETVAL
powerpc64/modules: replace stub allocation sentinel with an explicit counter
powerpc64/modules: correctly iterate over stubs in setup_ftrace_ool_stubs
powerpc/ftrace: ensure ftrace record ops are always set for NOPs
powerpc/603: Really copy kernel PGD entries into all PGDIRs
powerpc/8xx: Remove left-over instruction and comments in DataStoreTLBMiss handler
powerpc/pseries: HVPIPE changes to support migration
powerpc/pseries: Enable hvpipe with ibm,set-system-parameter RTAS
powerpc/pseries: Enable HVPIPE event message interrupt
...
Pull RISC-V updates from Paul Walmsley
- Replacement of __ASSEMBLY__ with __ASSEMBLER__ in header files (other
architectures have already merged this type of cleanup)
- The introduction of ioremap_wc() for RISC-V
- Cleanup of the RISC-V kprobes code to use mostly-extant macros rather
than open code
- A RISC-V kprobes unit test
- An architecture-specific endianness swap macro set implementation,
leveraging some dedicated RISC-V instructions for this purpose if
they are available
- The ability to identity and communicate to userspace the presence
of a MIPS P8700-specific ISA extension, and to leverage its
MIPS-specific PAUSE implementation in cpu_relax()
- Several other miscellaneous cleanups
* tag 'riscv-for-linus-6.18-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (39 commits)
riscv: errata: Fix the PAUSE Opcode for MIPS P8700
riscv: hwprobe: Document MIPS xmipsexectl vendor extension
riscv: hwprobe: Add MIPS vendor extension probing
riscv: Add xmipsexectl instructions
riscv: Add xmipsexectl as a vendor extension
dt-bindings: riscv: Add xmipsexectl ISA extension description
riscv: cpufeature: add validation for zfa, zfh and zfhmin
perf: riscv: skip empty batches in counter start
selftests: riscv: Add README for RISC-V KSelfTest
riscv: sbi: Switch to new sys-off handler API
riscv: Move vendor errata definitions to new header
RISC-V: ACPI: enable parsing the BGRT table
riscv: Enable ARCH_HAVE_NMI_SAFE_CMPXCHG
riscv: pi: use 'targets' instead of extra-y in Makefile
riscv: introduce asm/swab.h
riscv: mmap(): use unsigned offset type in riscv_sys_mmap
drivers/perf: riscv: Remove redundant ternary operators
riscv: mm: Use mmu-type from FDT to limit SATP mode
riscv: mm: Return intended SATP mode for noXlvl options
riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM
...
Pull arm64 updates from Will Deacon:
"There's good stuff across the board, including some nice mm
improvements for CPUs with the 'noabort' BBML2 feature and a clever
patch to allow ptdump to play nicely with block mappings in the
vmalloc area.
Confidential computing:
- Add support for accepting secrets from firmware (e.g. ACPI CCEL)
and mapping them with appropriate attributes.
CPU features:
- Advertise atomic floating-point instructions to userspace
- Extend Spectre workarounds to cover additional Arm CPU variants
- Extend list of CPUs that support break-before-make level 2 and
guarantee not to generate TLB conflict aborts for changes of
mapping granularity (BBML2_NOABORT)
- Add GCS support to our uprobes implementation.
Documentation:
- Remove bogus SME documentation concerning register state when
entering/exiting streaming mode.
Entry code:
- Switch over to the generic IRQ entry code (GENERIC_IRQ_ENTRY)
- Micro-optimise syscall entry path with a compiler branch hint.
Memory management:
- Enable huge mappings in vmalloc space even when kernel page-table
dumping is enabled
- Tidy up the types used in our early MMU setup code
- Rework rodata= for closer parity with the behaviour on x86
- For CPUs implementing BBML2_NOABORT, utilise block mappings in the
linear map even when rodata= applies to virtual aliases
- Don't re-allocate the virtual region between '_text' and '_stext',
as doing so confused tools parsing /proc/vmcore.
Miscellaneous:
- Clean-up Kconfig menuconfig text for architecture features
- Avoid redundant bitmap_empty() during determination of supported
SME vector lengths
- Re-enable warnings when building the 32-bit vDSO object
- Avoid breaking our eggs at the wrong end.
Perf and PMUs:
- Support for v3 of the Hisilicon L3C PMU
- Support for Hisilicon's MN and NoC PMUs
- Support for Fujitsu's Uncore PMU
- Support for SPE's extended event filtering feature
- Preparatory work to enable data source filtering in SPE
- Support for multiple lanes in the DWC PCIe PMU
- Support for i.MX94 in the IMX DDR PMU driver
- MAINTAINERS update (Thank you, Yicong)
- Minor driver fixes (PERF_IDX2OFF() overflow, CMN register offsets).
Selftests:
- Add basic LSFE check to the existing hwcaps test
- Support nolibc in GCS tests
- Extend SVE ptrace test to pass unsupported regsets and invalid
vector lengths
- Minor cleanups (typos, cosmetic changes).
System registers:
- Fix ID_PFR1_EL1 definition
- Fix incorrect signedness of some fields in ID_AA64MMFR4_EL1
- Sync TCR_EL1 definition with the latest Arm ARM (L.b)
- Be stricter about the input fed into our AWK sysreg generator
script
- Typo fixes and removal of redundant definitions.
ACPI, EFI and PSCI:
- Decouple Arm's "Software Delegated Exception Interface" (SDEI)
support from the ACPI GHES code so that it can be used by platforms
booted with device-tree
- Remove unnecessary per-CPU tracking of the FPSIMD state across EFI
runtime calls
- Fix a node refcount imbalance in the PSCI device-tree code.
CPU Features:
- Ensure register sanitisation is applied to fields in ID_AA64MMFR4
- Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM
guests can reliably query the underlying CPU types from the VMM
- Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes
to our context-switching, signal handling and ptrace code"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits)
arm64: cpufeature: Remove duplicate asm/mmu.h header
arm64: Kconfig: Make CPU_BIG_ENDIAN depend on BROKEN
perf/dwc_pcie: Fix use of uninitialized variable
arm/syscalls: mark syscall invocation as likely in invoke_syscall
Documentation: hisi-pmu: Add introduction to HiSilicon V3 PMU
Documentation: hisi-pmu: Fix of minor format error
drivers/perf: hisi: Add support for L3C PMU v3
drivers/perf: hisi: Refactor the event configuration of L3C PMU
drivers/perf: hisi: Extend the field of tt_core
drivers/perf: hisi: Extract the event filter check of L3C PMU
drivers/perf: hisi: Simplify the probe process of each L3C PMU version
drivers/perf: hisi: Export hisi_uncore_pmu_isr()
drivers/perf: hisi: Relax the event ID check in the framework
perf: Fujitsu: Add the Uncore PMU driver
arm64: map [_text, _stext) virtual address range non-executable+read-only
arm64/sysreg: Update TCR_EL1 register
arm64: Enable vmalloc-huge with ptdump
arm64: cpufeature: add Neoverse-V3AE to BBML2 allow list
arm64: errata: Apply workarounds for Neoverse-V3AE
arm64: cputype: Add Neoverse-V3AE definitions
...
sockopt-fastopen-key.pkt does not have the non-experimental
version, so the Experimental version is converted, FOEXP -> FO.
The test sets net.ipv4.tcp_fastopen_key=0-0-0-0 and instead
sets another key via setsockopt(TCP_FASTOPEN_KEY).
The first listener generates a valid cookie in response to TFO
option without cookie, and the second listner creates a TFO socket
using the valid cookie.
TCP_FASTOPEN_KEY is adjusted to use the common key in default.sh
so that we can use TFO_COOKIE and support dualstack. Similarly,
TFO_COOKIE_ZERO for the 0-0-0-0 key is defined.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-13-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This imports the non-experimental version of opt34/*-trigger-rst.pkt.
| accept() | SYN data |
-----------------------------------+----------+----------+
listener-closed-trigger-rst.pkt | no | unread |
unread-data-closed-trigger-rst.pkt | yes | unread |
Both files test that close()ing a SYN_RECV socket with unread SYN data
triggers RST.
The files are renamed to have the common prefix, trigger-rst.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-11-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This imports the non-experimental version of opt34/reset-*.pkt.
| Child | RST | sk_err |
---------------------------------+---------+-------------------------------+---------+
reset-after-accept.pkt | TFO | after accept(), SYN_RECV | read() |
reset-close-with-unread-data.pkt | TFO | after accept(), SYN_RECV | write() |
reset-before-accept.pkt | TFO | before accept(), SYN_RECV | read() |
reset-non-tfo-socket.pkt | non-TFO | before accept(), ESTABLISHED | write() |
The first 3 files test scenarios where a SYN_RECV socket receives RST
before/after accept() and data in SYN must be read() without error,
but the following read() or fist write() will return ECONNRESET.
The last test is similar but with non-TFO socket.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-10-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This imports the non-experimental version of icmp-before-accept.pkt.
This file tests the scenario where an ICMP unreachable packet for a
not-yet-accept()ed socket changes its state to TCP_CLOSE, but the
SYN data must be read without error, and the following read() returns
EHOSTUNREACH.
Note that this test support only IPv4 as icmp is used.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-9-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The only difference between non-experimental vs experimental TFO
option handling is SYN+ACK generation.
When tcp_parse_fastopen_option() parses a TFO option, it sets
tcp_fastopen_cookie.exp to false if the option number is 34,
and true if 255.
The value is carried to tcp_options_write() to generate a TFO option
with the same option number.
Other than that, all the TFO handling is the same and the kernel must
generate the same cookie regardless of the option number.
Let's add a test for the handling so that we can consolidate
fastopen/server/ tests and fastopen/server/opt34 tests.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-7-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This imports basic TFO server tests from google/packetdrill.
The repository has two versions of tests for most scenarios; one uses
the non-experimental option (34), and the other uses the experimental
option (255) with 0xF989.
This only imports the following tests of the non-experimental version
placed in [0]. I will add a specific test for the experimental option
handling later.
| TFO | Cookie | Payload |
---------------------------+-----+--------+---------+
basic-rw.pkt | yes | yes | yes |
basic-zero-payload.pkt | yes | yes | no |
basic-cookie-not-reqd.pkt | yes | no | yes |
basic-non-tfo-listener.pkt | no | yes | yes |
pure-syn-data.pkt | yes | no | yes |
The original pure-syn-data.pkt missed setsockopt(TCP_FASTOPEN) and did
not test TFO server in some scenarios unintentionally, so setsockopt()
is added where needed. In addition, non-TFO scenario is stripped as
it is covered by basic-non-tfo-listener.pkt. Also, I added basic- prefix.
Link: https://github.com/google/packetdrill/tree/bfc96251310f/gtests/net/tcp/fastopen/server/opt34 #[0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
TCP Fast Open cookie is generated in __tcp_fastopen_cookie_gen_cipher().
The cookie value is generated from src/dst IPs and a key configured by
setsockopt(TCP_FASTOPEN_KEY) or net.ipv4.tcp_fastopen_key.
The default.sh sets net.ipv4.tcp_fastopen_key, and the original packetdrill
defines the corresponding cookie as TFO_COOKIE in run_all.py. [0]
Then, each test does not need to care about the value, and we can easily
update TFO_COOKIE in case __tcp_fastopen_cookie_gen_cipher() changes the
algorithm.
However, some tests use the bare hex value for specific IPv4 addresses
and do not support IPv6.
Let's define the same TFO_COOKIE in ksft_runner.sh.
We will replace such bare hex values with TFO_COOKIE except for a single
test for setsockopt(TCP_FASTOPEN_KEY).
Link: https://github.com/google/packetdrill/blob/7230b3990f94/gtests/net/packetdrill/run_all.py#L65 #[0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To enable TCP Fast Open on a server, net.ipv4.tcp_fastopen must
have 0x2 (TFO_SERVER_ENABLE), and we need to do either
1. Call setsockopt(TCP_FASTOPEN) for the socket
2. Set 0x400 (TFO_SERVER_WO_SOCKOPT1) additionally to net.ipv4.tcp_fastopen
The default.sh sets 0x70403 so that each test does not need setsockopt().
(0x1 is TFO_CLIENT_ENABLE, and 0x70000 is ...???)
However, some tests overwrite net.ipv4.tcp_fastopen without
TFO_SERVER_WO_SOCKOPT1 and forgot setsockopt(TCP_FASTOPEN).
For example, pure-syn-data.pkt [0] tests non-TFO servers unintentionally,
except in the first scenario.
To prevent such an accident, let's require explicit setsockopt().
TFO_CLIENT_ENABLE is necessary for
tcp_syscall_bad_arg_fastopen-invalid-buf-ptr.pkt.
Link: https://github.com/google/packetdrill/blob/bfc96251310f/gtests/net/tcp/fastopen/server/opt34/pure-syn-data.pkt #[0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The cited commit forgot to update the ktap_set_plan call.
ktap_set_plan sets the number of tests (KSFT_NUM_TESTS), which must
match the number of executed tests (KTAP_CNT_PASS + KTAP_CNT_SKIP +
KTAP_CNT_XFAIL) in ktap_finished.
Otherwise, the selftest exit()s with 1.
Let's adjust KSFT_NUM_TESTS based on supported protocols.
While at it, misalignment is fixed up.
Fixes: a5c10aa3d1 ("selftests/net: packetdrill: Support single protocol test.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250927213022.1850048-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Here are a few sub-tests for mptcp_join.sh, validating the new 'laminar'
endpoint type.
In a setup where subflows created using the routing rules would be
rejected by the listener, and where the latter announces one IP address,
some cases are verified:
- Without any 'laminar' endpoints: no new subflows are created.
- With one 'laminar' endpoint: a second subflow is created.
- With multiple 'laminar' endpoints: 2 IPv4 subflows are created.
- With one 'laminar' endpoint, but the server announcing a second IP
address, only one subflow is created.
- With one 'laminar' + 'subflow' endpoint, the same endpoint is only
used once.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250927-net-next-mptcp-rcv-path-imp-v1-8-5da266aa9c1a@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull seccomp update from Kees Cook:
- Fix race with WAIT_KILLABLE_RECV (Johannes Nixdorf)
* tag 'seccomp-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests/seccomp: Add a test for the WAIT_KILLABLE_RECV fast reply race
seccomp: Fix a race with WAIT_KILLABLE_RECV if the tracer replies too fast
Pull namespace updates from Christian Brauner:
"This contains a larger set of changes around the generic namespace
infrastructure of the kernel.
Each specific namespace type (net, cgroup, mnt, ...) embedds a struct
ns_common which carries the reference count of the namespace and so
on.
We open-coded and cargo-culted so many quirks for each namespace type
that it just wasn't scalable anymore. So given there's a bunch of new
changes coming in that area I've started cleaning all of this up.
The core change is to make it possible to correctly initialize every
namespace uniformly and derive the correct initialization settings
from the type of the namespace such as namespace operations, namespace
type and so on. This leaves the new ns_common_init() function with a
single parameter which is the specific namespace type which derives
the correct parameters statically. This also means the compiler will
yell as soon as someone does something remotely fishy.
The ns_common_init() addition also allows us to remove ns_alloc_inum()
and drops any special-casing of the initial network namespace in the
network namespace initialization code that Linus complained about.
Another part is reworking the reference counting. The reference
counting was open-coded and copy-pasted for each namespace type even
though they all followed the same rules. This also removes all open
accesses to the reference count and makes it private and only uses a
very small set of dedicated helpers to manipulate them just like we do
for e.g., files.
In addition this generalizes the mount namespace iteration
infrastructure introduced a few cycles ago. As reminder, the vfs makes
it possible to iterate sequentially and bidirectionally through all
mount namespaces on the system or all mount namespaces that the caller
holds privilege over. This allow userspace to iterate over all mounts
in all mount namespaces using the listmount() and statmount() system
call.
Each mount namespace has a unique identifier for the lifetime of the
systems that is exposed to userspace. The network namespace also has a
unique identifier working exactly the same way. This extends the
concept to all other namespace types.
The new nstree type makes it possible to lookup namespaces purely by
their identifier and to walk the namespace list sequentially and
bidirectionally for all namespace types, allowing userspace to iterate
through all namespaces. Looking up namespaces in the namespace tree
works completely locklessly.
This also means we can move the mount namespace onto the generic
infrastructure and remove a bunch of code and members from struct
mnt_namespace itself.
There's a bunch of stuff coming on top of this in the future but for
now this uses the generic namespace tree to extend a concept
introduced first for pidfs a few cycles ago. For a while now we have
supported pidfs file handles for pidfds. This has proven to be very
useful.
This extends the concept to cover namespaces as well. It is possible
to encode and decode namespace file handles using the common
name_to_handle_at() and open_by_handle_at() apis.
As with pidfs file handles, namespace file handles are exhaustive,
meaning it is not required to actually hold a reference to nsfs in
able to decode aka open_by_handle_at() a namespace file handle.
Instead the FD_NSFS_ROOT constant can be passed which will let the
kernel grab a reference to the root of nsfs internally and thus decode
the file handle.
Namespaces file descriptors can already be derived from pidfds which
means they aren't subject to overmount protection bugs. IOW, it's
irrelevant if the caller would not have access to an appropriate
/proc/<pid>/ns/ directory as they could always just derive the
namespace based on a pidfd already.
It has the same advantage as pidfds. It's possible to reliably and for
the lifetime of the system refer to a namespace without pinning any
resources and to compare them trivially.
Permission checking is kept simple. If the caller is located in the
namespace the file handle refers to they are able to open it otherwise
they must hold privilege over the owning namespace of the relevant
namespace.
The namespace file handle layout is exposed as uapi and has a stable
and extensible format. For now it simply contains the namespace
identifier, the namespace type, and the inode number. The stable
format means that userspace may construct its own namespace file
handles without going through name_to_handle_at() as they are already
allowed for pidfs and cgroup file handles"
* tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits)
ns: drop assert
ns: move ns type into struct ns_common
nstree: make struct ns_tree private
ns: add ns_debug()
ns: simplify ns_common_init() further
cgroup: add missing ns_common include
ns: use inode initializer for initial namespaces
selftests/namespaces: verify initial namespace inode numbers
ns: rename to __ns_ref
nsfs: port to ns_ref_*() helpers
net: port to ns_ref_*() helpers
uts: port to ns_ref_*() helpers
ipv4: use check_net()
net: use check_net()
net-sysfs: use check_net()
user: port to ns_ref_*() helpers
time: port to ns_ref_*() helpers
pid: port to ns_ref_*() helpers
ipc: port to ns_ref_*() helpers
cgroup: port to ns_ref_*() helpers
...
Pull vfs mount updates from Christian Brauner:
"This contains some work around mount api handling:
- Output the warning message for mnt_too_revealing() triggered during
fsmount() to the fscontext log. This makes it possible for the
mount tool to output appropriate warnings on the command line.
For example, with the newest fsopen()-based mount(8) from
util-linux, the error messages now look like:
# mount -t proc proc /tmp
mount: /tmp: fsmount() failed: VFS: Mount too revealing.
dmesg(1) may have more information after failed mount system call.
- Do not consume fscontext log entries when returning -EMSGSIZE
Userspace generally expects APIs that return -EMSGSIZE to allow for
them to adjust their buffer size and retry the operation.
However, the fscontext log would previously clear the message even
in the -EMSGSIZE case.
Given that it is very cheap for us to check whether the buffer is
too small before we remove the message from the ring buffer, let's
just do that instead.
- Drop an unused argument from do_remount()"
* tag 'vfs-6.18-rc1.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
vfs: fs/namespace.c: remove ms_flags argument from do_remount
selftests/filesystems: add basic fscontext log tests
fscontext: do not consume log entries when returning -EMSGSIZE
vfs: output mount_too_revealing() errors to fscontext
docs/vfs: Remove mentions to the old mount API helpers
fscontext: add custom-prefix log helpers
fs: Remove mount_bdev
fs: Remove mount_nodev
Pull misc vfs updates from Christian Brauner:
"This contains the usual selections of misc updates for this cycle.
Features:
- Add "initramfs_options" parameter to set initramfs mount options.
This allows to add specific mount options to the rootfs to e.g.,
limit the memory size
- Add RWF_NOSIGNAL flag for pwritev2()
Add RWF_NOSIGNAL flag for pwritev2. This flag prevents the SIGPIPE
signal from being raised when writing on disconnected pipes or
sockets. The flag is handled directly by the pipe filesystem and
converted to the existing MSG_NOSIGNAL flag for sockets
- Allow to pass pid namespace as procfs mount option
Ever since the introduction of pid namespaces, procfs has had very
implicit behaviour surrounding them (the pidns used by a procfs
mount is auto-selected based on the mounting process's active
pidns, and the pidns itself is basically hidden once the mount has
been constructed)
This implicit behaviour has historically meant that userspace was
required to do some special dances in order to configure the pidns
of a procfs mount as desired. Examples include:
* In order to bypass the mnt_too_revealing() check, Kubernetes
creates a procfs mount from an empty pidns so that user
namespaced containers can be nested (without this, the nested
containers would fail to mount procfs)
But this requires forking off a helper process because you cannot
just one-shot this using mount(2)
* Container runtimes in general need to fork into a container
before configuring its mounts, which can lead to security issues
in the case of shared-pidns containers (a privileged process in
the pidns can interact with your container runtime process)
While SUID_DUMP_DISABLE and user namespaces make this less of an
issue, the strict need for this due to a minor uAPI wart is kind
of unfortunate
Things would be much easier if there was a way for userspace to
just specify the pidns they want. So this pull request contains
changes to implement a new "pidns" argument which can be set
using fsconfig(2):
fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd);
fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0);
or classic mount(2) / mount(8):
// mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc
mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid");
Cleanups:
- Remove the last references to EXPORT_OP_ASYNC_LOCK
- Make file_remove_privs_flags() static
- Remove redundant __GFP_NOWARN when GFP_NOWAIT is used
- Use try_cmpxchg() in start_dir_add()
- Use try_cmpxchg() in sb_init_done_wq()
- Replace offsetof() with struct_size() in ioctl_file_dedupe_range()
- Remove vfs_ioctl() export
- Replace rwlock() with spinlock in epoll code as rwlock causes
priority inversion on preempt rt kernels
- Make ns_entries in fs/proc/namespaces const
- Use a switch() statement() in init_special_inode() just like we do
in may_open()
- Use struct_size() in dir_add() in the initramfs code
- Use str_plural() in rd_load_image()
- Replace strcpy() with strscpy() in find_link()
- Rename generic_delete_inode() to inode_just_drop() and
generic_drop_inode() to inode_generic_drop()
- Remove unused arguments from fcntl_{g,s}et_rw_hint()
Fixes:
- Document @name parameter for name_contains_dotdot() helper
- Fix spelling mistake
- Always return zero from replace_fd() instead of the file descriptor
number
- Limit the size for copy_file_range() in compat mode to prevent a
signed overflow
- Fix debugfs mount options not being applied
- Verify the inode mode when loading it from disk in minixfs
- Verify the inode mode when loading it from disk in cramfs
- Don't trigger automounts with RESOLVE_NO_XDEV
If openat2() was called with RESOLVE_NO_XDEV it didn't traverse
through automounts, but could still trigger them
- Add FL_RECLAIM flag to show_fl_flags() macro so it appears in
tracepoints
- Fix unused variable warning in rd_load_image() on s390
- Make INITRAMFS_PRESERVE_MTIME depend on BLK_DEV_INITRD
- Use ns_capable_noaudit() when determining net sysctl permissions
- Don't call path_put() under namespace semaphore in listmount() and
statmount()"
* tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits)
fcntl: trim arguments
listmount: don't call path_put() under namespace semaphore
statmount: don't call path_put() under namespace semaphore
pid: use ns_capable_noaudit() when determining net sysctl permissions
fs: rename generic_delete_inode() and generic_drop_inode()
init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD
initramfs: Replace strcpy() with strscpy() in find_link()
initrd: Use str_plural() in rd_load_image()
initramfs: Use struct_size() helper to improve dir_add()
initrd: Fix unused variable warning in rd_load_image() on s390
fs: use the switch statement in init_special_inode()
fs/proc/namespaces: make ns_entries const
filelock: add FL_RECLAIM to show_fl_flags() macro
eventpoll: Replace rwlock with spinlock
selftests/proc: add tests for new pidns APIs
procfs: add "pidns" mount option
pidns: move is-ancestor logic to helper
openat2: don't trigger automounts with RESOLVE_NO_XDEV
namei: move cross-device check to __traverse_mounts
namei: remove LOOKUP_NO_XDEV check from handle_mounts
...
The fast path through a write will require replacing a single node in
the tree. Using a sheaf (32 nodes) is too heavy for the fast path, so
special case the node store operation by just allocating one node in the
maple state.
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Use prefilled sheaves instead of bulk allocations. This should speed up
the allocations and the return path of unused allocations.
Remove the push and pop of nodes from the maple state as this is now
handled by the slab layer with sheaves.
Testing has been removed as necessary since the features of the tree
have been reduced.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Add the prefilled sheaf structs to the slab header and the associated
functions to the testing/shared/linux.c file.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
There's some duplicated code and we are about to add more functionality
in maple-shared.h that we will need in the userspace maple test to be
available, so include it via maple-shim.c
Co-developed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
The slab changes for sheaves requires more effort in the testing code.
Unite all the kmem_cache work into the tools/include slab header for
both the vma and maple tree testing.
The vma test code also requires importing more #defines to allow for
seamless use of the shared kmem_cache code.
This adds the pthread header to the slab header in the tools directory
to allow for the pthread_mutex in linux.c.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Add the reset of the ref count in vma_lock_init(). This is needed if
the vma memory is not zeroed on allocation.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Bulk insert mode was added to facilitate forking faster, but forking now
uses __mt_dup() to duplicate the tree.
The addition of sheaves has made the bulk allocations difficult to
maintain - since the expected entries would preallocate into the maple
state. A big part of the maple state node allocation was the ability to
push nodes back onto the state for later use, which was essential to the
bulk insert algorithm.
Remove mas_expected_entries() and mas_destroy_rebalance() functions as
well as the MA_STATE_BULK and MA_STATE_REBALANCE maple state flags since
there are no users anymore. Drop the associated testing as well.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
ASoC: Updates for v6.18 round 2
Some more updates for v6.18, mostly fixes for the earlier pull request
with some cleanups and more minor fixes for older code. We do have one
new driver, the TI TAS2783A, and some quirks for new platforms.
Paolo Bonzini