Commit Graph

802 Commits

Author SHA1 Message Date
Harald Freudenberger
98d23edcd4 s390/zcrypt: Fix uninitialized padding in CRT key structure
The zcrypt_type6_crt_key() function leaves padding bytes uninitialized
between key components and the modulus in the CCA CRT key token. These
padding bytes are sent to the crypto card, potentially leaking kernel
memory contents.

The initial memset() only zeros fixed structure fields, not the
flexible array member key_parts[] where the padding resides. While key
components are properly copied from userspace, the calculated pad_len
bytes between them remain uninitialized.

Fix by explicitly zeroing the padding bytes after copying the CRT key
components.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-01 12:44:48 +02:00
Holger Dengler
a91a5c25a2 s390/zcrypt: Validate length in reply before using it
The length information in the reply is used to copy the key token to
the target buffer. An invalid information in t->len of the reply may
cause an over-read of the target buffer and also a over-write of the
target buffer. To prevent that, check t->len before using it.

As the available space in destination and source buffer is always
larger than the valid length value in the parameter block in the
reply, compare t->len with this (already validated) length
information. As a side effect, this check also prevents buffer
over-read and over-write.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-08-31 16:25:38 +02:00
Linus Torvalds
7bb6284aa7 Arm:
* Add support for 'slot' based PMU events, paired with new UAPI that
   compels the user to select a specific PMU implementation
 
 * Lazy save/restore of vCPU state for pKVM, along with various fixes
   and cleanups to the management of vCPU state between the untrusted
   host and pKVM hypervisor
 
 * Disable traps of EL1 registers for nested hypervisors when FEAT_NV2p1
   is present, guaranteeing that EL2-specific register bits are stateful
   in the EL1 counterpart
 
 * Leverage FEAT_NV3 to avoid unnecessary ERET/TLBI traps when the scope
   of those instructions remains 'in host' (i.e. L1 kernel/userspace)
 
 * Pile of fixes for the management of the VNCR pseudo-TLB, such as
   under-invalidations and races with concurrent TLBIs on other vCPUs
 
 * Consolidate the non-protected and pKVM view of ICH_VTR_EL2 to a
   runtime-patched constant, allowing the same data to be shared with
   pKVM prior to dropping host privileges
 
 * Considerable pile of LLM-assisted fixes around the shop but mostly in
   the VGIC, our in-kernel generator of bugs (and sometimes interrupts)
 
 LoongArch:
 
 * Advertise already-supported capabilities.
 
 * Some bug fixes about timer and MMIO.
 
 * Some hardening about interrupt injection.
 
 * Replace kvm_err() with kvm_pr_unimpl().
 
 * Add FPU/LSX/LASX test cases for selftests.
 
 RISC-V:
 
 * Svadu/Zicfiss/Zicfilp FWFT support for Guest
 
 * Use try_cmpxchg for IMSIC MRIF RMW
 
 * More arch-specific tracepoints in KVM RISC-V
 
 * Eager page splitting when enabling dirty logging
 
 * Optimize hfence request handling for SMP Guests
 
 * Improve dirty log clearing by skipping zero bits in mask
 
 * Guard HFENCE range loops against overflow
 
 * CPU PM notifiers in KVM RISC-V for non-retentive idle states
 
 * Fix kernel-mode vector context save/restore for Guest
 
 s390:
 
 * Fixes for vfio-ap
 
 * Fixes for the gmap rework
 
 * Fixes for vsie
 
 * AI triggered fixes all over
 
 * diag9c tracing
 
 * code move preparation for the additional arm64 support
 
 * enable CONTEXT_ANALYSIS
 
 x86:
 
 * Perform spring cleaning on x86.{c,h} and asm/kvm_host.h, by adding regs.c
   (the kvm_cache_regs.h => regs.h is already applied) and msrs.{c,h}, and moving
   relevant code out of x86.c.
 
 * Split kvm_mmu in three parts, respectively to describe the format of page
   tables, walking the guest page tables and building the page tables.  Always
   use the same page table walker kvm->arch.gva_walk as the entry point to
   convert a guest's virtual address, where the previous code used two
   different kvm_mmu structs depending on whether the walk included nested
   EPT/NPT or not.  Make page fault vmexits reuse the permission checking
   machinery that is used for guest page faults.  This is both a cleanup
   and a baby step towards supporting XS/XU memory permissions.
 
 * Document some of the "fun" gotchas with the APIC base when creating IRQCHIPs
   on x86.
 
 * Remove a defunct masterclock update from kvm_xen_shared_info_init().  It
   could result in incorrect kvmclock due to triggering an unnecessary
   switch to/from masterclock mode.
 
 * Skip Xen runstate time updates if time has effectively gone backwards, so
   that the guest doesn't report 100% steal time for a very, very long time.
 
 * Drop KVM's runtime updates of the Xen PV timing CPUID leaf, as KVM was
   updating the wrong sub-leaf, and upstream KVM will soon provide all the
   information needed by userspace to populate the CPUID field itself.
 
 * Fix a bug where KVM would walk a newly created rmap without holding the rmap
   lock (or mmu_lock) during aging.
 
 * Fix a bug where aging TDP MMU SPTEs could clobber FROZEN SPTEs.
 
 * Fix a variety of #DB priority bugs.
 
 * Fix a class of races related to enabling Hyper-V emulation on a vCPU after
   the vCPU is visible to the rest of KVM.
 
 * Use static calls for nested virtualization ops.
 
 * Move more KVM-internal code out of x86's kvm_host.h.
 
 * Enumerate support for a variety of Zhaoxin instructions that don't require
   explicit virtualization.
 
 * Fix missing EFER validation bugs, including in the KVM_SET_SREGS* path.
 
 * Harden kvm_vcpu_map() against double-mapping and thus leaking references.
 
 * Misc fixes and cleanups, e.g. for largely benign syzkaller splats.
 
 x86 (Intel):
 
 * Zero a vCPU's entry in VMX's Posted Interrupt Descriptor table used for IPI
   virtualization when the vCPU is freed, to fix a use-after-free where hardware
   will write to a freed vCPU's PID.
 
 * Service local TLB flushes on a failed nested VM-Enter to fix a bug where KVM
   could miss a TLB on a future, successful VM-Enter with the same L2 VPID.
 
 * Cap the maximum value shoved into the VMX Preemption Timer to workaround an
   erratum that affects all existing Intel CPUs that support CPUID 0x15.
 
 * Fix VPID virtualization bugs where KVM would fail to flush hardware TLBs.
 
 * Harden the TDX "populate" ioctls against bad input, and to prepare
   for supporting in-place private<=>shared conversion.
 
 x86 (AMD):
 
 * Forcefully invalidate SNP VMSA pages if their backing guest_memfd page is
   zapped/invalidated, e.g. due to a PUNCH_HOLE in response to a Page-State
   Change request.
 
 * Remove a dying VM from the GA Log notifier list before the VM is actually
   destroyed, to fix a potential use-after-free.
 
 * While FOLL_WRITE was needed in the past to trigger CoW unsharing, nowadays
   FOLL_LONGTERM does that already even without FOLL_WRITE, and in fact,
   get_user_pages() actually disallows FOLL_WRITE together with FOLL_LONGTERM.
   So don't pass FOLL_WRITE when registering encrypted memory regions, i.e. when
   pinning SEV/SEV-ES guest memory, to fix a regression with file-backed memory
   introduced by KVM's (correct) usage of long-term pins.
 
   (This was reviewed by mm maintainers; for more information, see commit
   ee1a586dd1).
 
 * Allocate full pages for SEV/SEV-ES {DE,EN}CRYPT ops on SNP-enabled hosts to
   fix a data corruption issue due to the PSP driver assigning to-be-written
   pages to firmware (as required by the SNP specs).
 
 * Unconditionally intercept ICBEP so that KVM generates the correct guest RIP
   when handling an ICEBP-induced TASK_SWITCH #VMEXIT.
 
 * Harden the SNP "populate" ioctls against bad input, and to prepare
   for supporting in-place private<=>shared conversion.
 
 Generic:
 
 * Remove kvm_debugfs_dir if kvm_init() fails after creating KVM's debugfs.
 
 * Add a per-VM bitmap to track which vCPU IDs have been "claimed" but for
   which the vCPU isn't yet online, and use the bitmap to reject duplicate IDs
   before calling into arch code.  This allows arch code to consume vcpu_id
   without having to worry about cross-vCPU clobbering (at least s390 and x86
   have had related bugs).
 
 * Rework the so called "prepare" and "invalidate" guest_memfd hooks to prepare
   for in-place private<=>shared conversion, and clean up a few warts along the
   way.
 
 Selftests:
 
 * Automatically allocate a full page for L2 guest stacks on x86 instead of
   requiring test-specific L1 guest code to carve out a portion of the L1
   stack for L2 usage, and to ensure the L2 stack also adheres to the x86-64
   calling convention ABI.
 
 * Add a selftest to verify {Guest,Host}-Only behavior in x86's mediated PMU.
 
 * Clean up nested SVM's handling of GPRs on L2<=>L1 transitions, reuse the
   functionality for nested VMX, and drop the ucall hack that was fudging
   around the lack of GPR switching on nVMX.
 
 * Add a stress test to verify KVM doesn't clobber/drop #PF state, e.g. CR2,
   across save/restore, including when L2 is active.
 
 * Add a test to verify KVM_CREATE_VM accepts exactly what is reported by
   KVM_CAP_VM_TYPES.
 
 * Misc selftests fixes and cleanups
 
 * Fix several issues with seeding the pRNG, and rework the pRNG APIs to that
   the pRNG can be sanely used in host code, not just guest code.
 
 * Add an IRQ test to validate virtual IRQ deliverty for IRQs wired up via
   KVM_IRQFD + KVM_SET_GSI_ROUTING, with optional support for triggering IRQs
   via writes to an assigned VFIO device.
 
 * Add syscall wrappers to assert success on a variety of pthreads and CPU
   affinity APIs.
 
 * Set vCPU pthread affinity as early as possible to reduce contention issues
   that were surfaced by PREEMPT_LAZY, which result in runtimes of over a
   minute on large hosts, versus the expected ~5 seconds.
 
 * Rework the PMU counters test to run each testcase using a single VM with
   many vCPUs for each sub-testcase, instead of using a unique VM for each
   sub-testcase.  This cuts the runtime by ~20x.
 
 Miscellaneous:
 
 * MAINTAINERS updates for vfio-ap, guest_memfd, kvm-x86.  Mostly representing
   the status quo more accurately, but also... welcome David Hildenbrand
   as guest_memfd reviewer!
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM64:

   - Add support for 'slot' based PMU events, paired with new UAPI that
     compels the user to select a specific PMU implementation

   - Lazy save/restore of vCPU state for pKVM, along with various fixes
     and cleanups to the management of vCPU state between the untrusted
     host and pKVM hypervisor

   - Disable traps of EL1 registers for nested hypervisors when
     FEAT_NV2p1 is present, guaranteeing that EL2-specific register bits
     are stateful in the EL1 counterpart

   - Leverage FEAT_NV3 to avoid unnecessary ERET/TLBI traps when the
     scope of those instructions remains 'in host' (i.e. L1
     kernel/userspace)

   - Pile of fixes for the management of the VNCR pseudo-TLB, such as
     under-invalidations and races with concurrent TLBIs on other vCPUs

   - Consolidate the non-protected and pKVM view of ICH_VTR_EL2 to a
     runtime-patched constant, allowing the same data to be shared with
     pKVM prior to dropping host privileges

   - Considerable pile of LLM-assisted fixes around the shop but mostly
     in the VGIC, our in-kernel generator of bugs (and sometimes
     interrupts)

  LoongArch:

   - Advertise already-supported capabilities

   - Some bug fixes about timer and MMIO

   - Some hardening about interrupt injection

   - Replace kvm_err() with kvm_pr_unimpl()

   - Add FPU/LSX/LASX test cases for selftests

  RISC-V:

   - Svadu/Zicfiss/Zicfilp FWFT support for Guest

   - Use try_cmpxchg for IMSIC MRIF RMW

   - More arch-specific tracepoints in KVM RISC-V

   - Eager page splitting when enabling dirty logging

   - Optimize hfence request handling for SMP Guests

   - Improve dirty log clearing by skipping zero bits in mask

   - Guard HFENCE range loops against overflow

   - CPU PM notifiers in KVM RISC-V for non-retentive idle states

   - Fix kernel-mode vector context save/restore for Guest

  s390:

   - Fixes for vfio-ap

   - Fixes for the gmap rework

   - Fixes for vsie

   - AI triggered fixes all over

   - diag9c tracing

   - code move preparation for the additional arm64 support

   - enable CONTEXT_ANALYSIS

  x86:

   - Perform spring cleaning on x86.{c,h} and asm/kvm_host.h, by adding
     regs.c (the kvm_cache_regs.h => regs.h is already applied) and
     msrs.{c,h}, and moving relevant code out of x86.c

   - Split kvm_mmu in three parts, respectively to describe the format
     of page tables, walking the guest page tables and building the page
     tables. Always use the same page table walker kvm->arch.gva_walk as
     the entry point to convert a guest's virtual address, where the
     previous code used two different kvm_mmu structs depending on
     whether the walk included nested EPT/NPT or not. Make page fault
     vmexits reuse the permission checking machinery that is used for
     guest page faults. This is both a cleanup and a baby step towards
     supporting XS/XU memory permissions

   - Document some of the "fun" gotchas with the APIC base when creating
     IRQCHIPs on x86

   - Remove a defunct masterclock update from kvm_xen_shared_info_init().
     It could result in incorrect kvmclock due to triggering an
     unnecessary switch to/from masterclock mode

   - Skip Xen runstate time updates if time has effectively gone
     backwards, so that the guest doesn't report 100% steal time for
     a very, very long time

   - Drop KVM's runtime updates of the Xen PV timing CPUID leaf, as KVM
     was updating the wrong sub-leaf, and upstream KVM will soon provide
     all the information needed by userspace to populate the CPUID field
     itself

   - Fix a bug where KVM would walk a newly created rmap without holding
     the rmap lock (or mmu_lock) during aging

   - Fix a bug where aging TDP MMU SPTEs could clobber FROZEN SPTEs

   - Fix a variety of #DB priority bugs

   - Fix a class of races related to enabling Hyper-V emulation on a
     vCPU after the vCPU is visible to the rest of KVM

   - Use static calls for nested virtualization ops

   - Move more KVM-internal code out of x86's kvm_host.h

   - Enumerate support for a variety of Zhaoxin instructions that don't
     require explicit virtualization

   - Fix missing EFER validation bugs, including in the KVM_SET_SREGS*
     path

   - Harden kvm_vcpu_map() against double-mapping and thus leaking
     references

   - Misc fixes and cleanups, e.g. for largely benign syzkaller splats

  x86 (Intel):

   - Zero a vCPU's entry in VMX's Posted Interrupt Descriptor table used
     for IPI virtualization when the vCPU is freed, to fix a
     use-after-free where hardware will write to a freed vCPU's PID

   - Service local TLB flushes on a failed nested VM-Enter to fix a bug
     where KVM could miss a TLB on a future, successful VM-Enter with
     the same L2 VPID

   - Cap the maximum value shoved into the VMX Preemption Timer to
     workaround an erratum that affects all existing Intel CPUs that
     support CPUID 0x15

   - Fix VPID virtualization bugs where KVM would fail to flush hardware
     TLBs

   - Harden the TDX "populate" ioctls against bad input, and to prepare
     for supporting in-place private<=>shared conversion

  x86 (AMD):

   - Forcefully invalidate SNP VMSA pages if their backing guest_memfd
     page is zapped/invalidated, e.g. due to a PUNCH_HOLE in response to
     a Page-State Change request

   - Remove a dying VM from the GA Log notifier list before the VM is
     actually destroyed, to fix a potential use-after-free

   - While FOLL_WRITE was needed in the past to trigger CoW unsharing,
     nowadays FOLL_LONGTERM does that already even without FOLL_WRITE,
     and in fact, get_user_pages() actually disallows FOLL_WRITE
     together with FOLL_LONGTERM. So don't pass FOLL_WRITE when
     registering encrypted memory regions, i.e. when pinning SEV/SEV-ES
     guest memory, to fix a regression with file-backed memory
     introduced by KVM's (correct) usage of long-term pins

     (This was reviewed by mm maintainers; for more information, see
     commit ee1a586dd1 "KVM: SEV: Drop FOLL_WRITE for encrypted region
     registration")

   - Allocate full pages for SEV/SEV-ES {DE,EN}CRYPT ops on SNP-enabled
     hosts to fix a data corruption issue due to the PSP driver
     assigning to-be-written pages to firmware (as required by the SNP
     specs)

   - Unconditionally intercept ICBEP so that KVM generates the correct
     guest RIP when handling an ICEBP-induced TASK_SWITCH #VMEXIT

   - Harden the SNP "populate" ioctls against bad input, and to prepare
     for supporting in-place private<=>shared conversion

  Generic:

   - Remove kvm_debugfs_dir if kvm_init() fails after creating KVM's
     debugfs

   - Add a per-VM bitmap to track which vCPU IDs have been "claimed" but
     for which the vCPU isn't yet online, and use the bitmap to reject
     duplicate IDs before calling into arch code. This allows arch code
     to consume vcpu_id without having to worry about cross-vCPU
     clobbering (at least s390 and x86 have had related bugs)

   - Rework the so called "prepare" and "invalidate" guest_memfd hooks
     to prepare for in-place private<=>shared conversion, and clean up a
     few warts along the way

  Selftests:

   - Automatically allocate a full page for L2 guest stacks on x86
     instead of requiring test-specific L1 guest code to carve out a
     portion of the L1 stack for L2 usage, and to ensure the L2 stack
     also adheres to the x86-64 calling convention ABI

   - Add a selftest to verify {Guest,Host}-Only behavior in x86's
     mediated PMU

   - Clean up nested SVM's handling of GPRs on L2<=>L1 transitions,
     reuse the functionality for nested VMX, and drop the ucall hack
     that was fudging around the lack of GPR switching on nVMX

   - Add a stress test to verify KVM doesn't clobber/drop #PF state,
     e.g. CR2, across save/restore, including when L2 is active

   - Add a test to verify KVM_CREATE_VM accepts exactly what is reported
     by KVM_CAP_VM_TYPES

   - Misc selftests fixes and cleanups

   - Fix several issues with seeding the pRNG, and rework the pRNG APIs
     to that the pRNG can be sanely used in host code, not just guest
     code

   - Add an IRQ test to validate virtual IRQ deliverty for IRQs wired up
     via KVM_IRQFD + KVM_SET_GSI_ROUTING, with optional support for
     triggering IRQs via writes to an assigned VFIO device

   - Add syscall wrappers to assert success on a variety of pthreads and
     CPU affinity APIs

   - Set vCPU pthread affinity as early as possible to reduce contention
     issues that were surfaced by PREEMPT_LAZY, which result in runtimes
     of over a minute on large hosts, versus the expected ~5 seconds

   - Rework the PMU counters test to run each testcase using a single VM
     with many vCPUs for each sub-testcase, instead of using a unique VM
     for each sub-testcase. This cuts the runtime by ~20x

  Miscellaneous:

   - MAINTAINERS updates for vfio-ap, guest_memfd, kvm-x86. Mostly
     representing the status quo more accurately, but also... welcome
     David Hildenbrand as guest_memfd reviewer!"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (413 commits)
  KVM: arm64: Validate GICv5 timer PPIs before claiming ownership
  KVM: arm64: vgic: Reject out-of-range GICv5 PPI IDs
  KVM: arm64: vgic: Prevent speculative SPI array underflow
  KVM: arm64: vgic: Free gic_kvm_info on initialization failure
  KVM: arm64: Avoid mismatched accesses to 'struct kvm_nvhe_init_params'
  s390/vfio-ap: Fix NULL deref in status_show() during queue probe
  s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed
  s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap
  s390/vfio-ap: Fix control domain removal in vfio_ap_mdev_cfg_remove
  s390/vfio-ap: Fix required lock not held during update of ap_matrix_mdev object
  s390/vfio-ap: Fix missing lock required to access list of ap_matrix_mdev objects
  s390/vfio-ap: Fix dereference matrix_mdev->kvm without checking for NULL
  s390/vfio-ap: Fix stale do_remove flag across iterations in vfio_ap_mdev_cfg_remove
  RISC-V: KVM: fix vcpu vector context handling for kernel-mode vector
  riscv: vector: allow non-preemptible kernel-mode vector with IRQs off
  riscv: vector: refactor riscv_v_start_kernel_context
  KVM: s390: gmap: Make prefix handling optional
  KVM: s390: gmap: Make CMMA optional
  KVM: s390: gmap: Make storage keys optional
  KVM: s390: Prepare gmap for a second KVM implementation
  ...
2026-08-25 11:48:04 -07:00
Linus Torvalds
66ec24c5d7 s390 updates for 7.3 merge window
- Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS
 
 - Add kCFI support using the generic support provided by Clang
 
 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking
 
 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround
 
 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks
 
 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to
 
 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration
 
 - Remove/replace cond_resched() calls which are no-ops with the supported
   s390 preemption models
 
 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future hardware
   could report values which were handled incorrectly
 
 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining
 
 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only
 
 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting
 
 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings
 
 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump
 
 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL
 
 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers
 
 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is exhausted
 
 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for complex
   code paths such as btrfs
 
 - Simplify IPL, trap and syscall code and remove the obsolete unistd_32.h
   generation entry
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Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS

 - Add kCFI support using the generic support provided by Clang

 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking

 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround

 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks

 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to

 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration

 - Remove/replace cond_resched() calls which are no-ops with the
   supported s390 preemption models

 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future
   hardware could report values which were handled incorrectly

 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining

 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only

 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting

 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings

 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump

 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL

 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers

 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is
   exhausted

 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for
   complex code paths such as btrfs

 - Simplify IPL, trap and syscall code and remove the obsolete
   unistd_32.h generation entry

* tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
  s390/percpu: Fix MVIY_PERCPU() with older binutils
  s390/debug: Fix deadlock during unregister
  s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks
  s390: Enable CONTEXT_ANALYSIS for various directories
  s390/mm: Add __context_unsafe() attribute to gmap helper functions
  s390/mm: Add __context_unsafe() attribute to do_secure_storage_access()
  s390/sysinfo: Add context analysis attributes
  s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN
  s390/virtio: Enable CONTEXT_ANALYSIS
  s390/cio: Enable CONTEXT_ANALYSIS
  s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce()
  s390/pci: Enable CONTEXT_ANALYSIS
  s390/pci: Rework __zpci_event_availability() to remove conditional locking
  s390/pci: Rework __zpci_event_error() to remove conditional locking
  s390/char: Enable CONTEXT_ANALYSIS
  s390/con3215: Add __must_hold() attribute to raw3215_make_room()
  s390/ap: Fix MAPML computation
  s390/cio: Remove cond_resched() calls
  s390: Remove cond_resched() calls
  KVM: s390: Remove cond_resched() calls
  ...
2026-08-23 10:26:44 -07:00
Paolo Bonzini
4136288688 LoongArch KVM changes for v7.3
1. Advertise already-supported capabilities.
 2. Some bug fixes about timer and MMIO.
 3. Some hardening about interrupt injection.
 4. Replace kvm_err() with kvm_pr_unimpl().
 5. Add FPU/LSX/LASX test cases for selftests.
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Merge tag 'loongarch-kvm-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v7.3

1. Advertise already-supported capabilities.
2. Some bug fixes about timer and MMIO.
3. Some hardening about interrupt injection.
4. Replace kvm_err() with kvm_pr_unimpl().
5. Add FPU/LSX/LASX test cases for selftests.
2026-08-18 13:11:45 +02:00
Paolo Bonzini
1526a27e79 Merge tag 'kvm-s390-next-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Features and Fixes for 7.3

- merged kvms390/master to pick up additional fixes that came too late
  for 7.2
- Fixes for vfio-ap
- Fixes for the gmap rework
- Fixes for vsie
- AI triggered fixes all over
- diag9c tracing
- code move preparation for the additional arm64 support
- enable CONTEXT_ANALYSIS
- update to vfio maintainer file location
2026-08-18 13:10:00 +02:00
Anthony Krowiak
dd6f4ef6f8 s390/vfio-ap: Fix NULL deref in status_show() during queue probe
When vfio_ap_mdev_probe_queue() creates the sysfs attribute group,
the queue's driver data has not yet been set. A concurrent read of
the 'status' attribute can therefore call dev_get_drvdata() and
get NULL, which is then passed directly to
vfio_ap_mdev_for_queue() where q->apqn is unconditionally
dereferenced, causing a NULL pointer dereference.

Fix this by acquiring the update locks before calling
sysfs_create_group(). The status_show() function acquires
guests_lock before reading the driver data, so any concurrent
read will block until after dev_set_drvdata() has been called
and the update locks are released.

As a bonus, the APQN no longer needs to be read from the queue
struct after allocation — it can be read directly from apdev
before allocation and stored in a local variable, which is then
assigned to q->apqn once the allocation succeeds.

Fixes: 260f3ea141 ("s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.c")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:33 +02:00
Anthony Krowiak
917f509bfb s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed
The vfio_ap_mdev_hot_unplug_cfg() function uses the return value of
bitmap_andnot() to determine whether the guest APCB needs to be updated.
However, bitmap_andnot() returns false when the resulting destination
bitmap is empty. This means that if the only adapter, domain or control
domain assigned to an mdev is removed from the host's AP configuration,
the bit is correctly cleared from the shadow APCB, but bitmap_andnot()
returns false because the result is an empty bitmap. Consequently,
do_hotplug remains 0 and vfio_ap_mdev_update_guest_apcb() is never called,
leaving the KVM guest with stale hardware access to the unplugged AP
devices.

Fix this by replacing the bitmap_andnot() return value check with
bitmap_intersects() to determine whether the shadow APCB actually
overlaps with the removal mask. If there is an intersection, call
bitmap_andnot() solely for its side effect of clearing the bits, then
unconditionally set do_hotplug to trigger the guest APCB update.

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:33 +02:00
Anthony Krowiak
bf09b9d7cd s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap
The DECLARE_BITMAP(apm_filtered, AP_DEVICES) macro allocates the bitmap
on the stack without zero-initializing it.

In vfio_ap_mdev_hot_plug_cfg(), the vfio_ap_mdev_filter_matrix() function
is only called to initialize and populate apm_filtered if either
filter_adapters or filter_domains is true. If the hot plug configuration
change only adds control domains (meaning filter_cdoms is true, but
filter_adapters and filter_domains are both false),
vfio_ap_mdev_filter_matrix() is bypassed.

Consequently, apm_filtered is passed to reset_queues_for_apids() with
uninitialized stack garbage. This can cause reset_queues_for_apids() to
interpret arbitrary stack garbage bits as valid APIDs to reset, potentially
performing unintended guest hardware queue resets.

Fix this by zero-initializing the apm_filtered bitmap at the beginning of
vfio_ap_mdev_hot_plug_cfg() using bitmap_zero().

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:33 +02:00
Anthony Krowiak
6b8a02e216 s390/vfio-ap: Fix control domain removal in vfio_ap_mdev_cfg_remove
The vfio_ap_config_remove function uses the bitmap_andnot function to clear
bits from the matrix_mdev->matrix.adm bitmap (specifies the control domains
assigned to the mdev). This prevents the explicitly unplugged control
domains from being removed the KVM guest. The bitmap_and function is used
instead.

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:33 +02:00
Anthony Krowiak
5883528250 s390/vfio-ap: Fix required lock not held during update of ap_matrix_mdev object
In the vfio_ap_mdev_cfg_add function, the apm_add, aqm_add and adm_add
fields of an ap_matrix_mdev object fields are modified while not holding
the matrix_dev->mdevs_lock. This lock must be held while making these
to guard against a race condition with another caller that may be
concurrently modifying these fields or any of the fields in the
matrix_mdev->matrix.

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:33 +02:00
Anthony Krowiak
7fa61c2985 s390/vfio-ap: Fix missing lock required to access list of ap_matrix_mdev objects
In order to traverse or add/remove ap_matrix_mdev objects in the
matrix_dev->mdev_list, the matrix_dev->guests_lock mutex must be held.
There are two functions that access the list without holding the mutex:

vfio_ap_mdev_probe function
~~~~~~~~~~~~~~~~~~~~~~~~~~~
The vfio_ap_mdev_probe function uses the matrix_dev->mdevs_lock
mutex to guard the add of a newly created ap_matrix_mdev object to the
matrix_dev->mdev_list. This mutex does not protect list access; its purpose
is to guard against concurrent access to fields contained in an
ap_matrix_mdev object. This could lead to kernel memory corruption or
use-after-free if another mdev is created or removed concurrently.

The adding of an ap_matrix_mdev object to matrix_dev->mdev_list
is now guarded by the matrix_dev->guests_lock which is the correct
way to protect against concurrent mdev_list access.

Also removed the following two lines of code because the matrix_mdev is
allocated via vfio_alloc_device macro which uses kzalloc, so req_trigger
and cfg_chg_trigger are already zero-initialised when the struct is
allocated before the call to vfio_register_emulated_iommu_dev. This
prevents a window whereby these triggers are set to NULL after
the device is exposed to userspace.

matrix_mdev->req_trigger = NULL;
matrix_mdev->cfg_chg_trigger = NULL;

vfio_ap_mdev_for_queue function
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The status_show function that supports display of the status attribute of
the devices in /sys/bus/ap/devices calls the vfio_ap_mdev_for_queue
function which iterates the matrix_dev->mdev_list to find the object
representing the queue device whose status is to be displayed. In order to
traverse this list, the matrix_dev->guests_lock mutex must be held.

To fix this, the guests_lock mutex is taken prior to taking the
matrix_dev->mdevs_lock mutex in the status_show function. It is taken
there rather than the vfio_ap_mdev_for_queue function - where it is
needed - because it must be taken prior to the mdevs_lock mutex in order to
adhere to the proper locking order and prevent a lockdep splat; also
because the mdevs_lock is needed there to access fields within
the matrix_mdev object in that function.

See the vfio-ap-locking.rst in the linux kernel tree.

Fixes: 2c1ee8983a ("s390/vfio-ap: prepare for dynamic update of guest's APCB on queue probe/remove")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:32 +02:00
Anthony Krowiak
d50346801b s390/vfio-ap: Fix dereference matrix_mdev->kvm without checking for NULL
The ap_driver structure has two fields which are function pointers to
callbacks:

* .on_config_changed: called at the start of the AP bus scan function to
                      notify the device driver that the host AP
                      configuration has changed and the associated AP
                      devices will be added or removed accordingly. This
                      gives the implementor a chance to evaluate the
                      configuration changes and respond to them before
                      the associated devices are added or removed.

* .on_scan_complete:  Called at the end of the AP bus scan function to
                      notify the device driver that the host AP
                      configuration has changed and the AP devices have
                      been added or removed accordingly. This gives the
                      implementor the opportunity to respond to the
                      changes after the associated devices are added or
                      removed.

These two callbacks are implemented in the vfio_ap device driver via the
vfio_ap_on_cfg_changed and vfio_ap_on_scan_complete functions respectively.

Within the call stack of these two callback functions the
matrix_mdev->kvm->lock mutex is taken without checking whether
matrix_mdev->kvm is NULL or not. If matrix_mdev->kvm has never been set,
trying to take the lock will trigger a NULL pointer dereference. This patch
adds checks for matrix_mdev->kvm == NULL before taking the
matrix_mdev->kvm->lock mutex.

Note that the matrix_mdev->kvm->lock mutex taken in the
vfio_ap_mdev_hot_plug_config function is moved to the calling function
along with the matrix_dev->mdevs_lock which is needed there to access
the fields of the matrix_mdev. It makes little sense to make the change
the check for matrix_mdev->kvm there before taking the kvm->lock
mutex only to have to move it out via another patch, so it is done in
this patch.

It is important to make note of the following:
1. The matrix_dev->guests_lock is acquired at the start of both callback
   functions. This ensures that matrix_mdev will not be removed via the
   vfio_ap_mdev_remove function because it too takes matrix_dev_guests_lock
   before removing the object; so, matrix_mdev will be available for the
   duration of the callback functions.

2. The matrix_dev->mdevs_lock mutex must be taken in order to access
   fields within the matrix_mdev structure

3. matrix_mdev->kvm->lock mutex must be taken before the
   matrix_dev->mdevs_lock to prevent a lockdep splat.

4: The kvm->lock must be held while plugging the guest's AP configuration
   into its SIE state description via the vfio_ap_mdev_update_guest_apcb
   function.

5. The vfio_ap_mdev_update_guest_apcb checks matrix_mdev->kvm to verify it
   is not NULL before doing the hot plug of the guest's AP configuration.

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:32 +02:00
Anthony Krowiak
b1f092d94f s390/vfio-ap: Fix stale do_remove flag across iterations in vfio_ap_mdev_cfg_remove
The do_remove flag in vfio_ap_mdev_cfg_remove() is initialised to zero
before the loop that iterates over the list of matrix mdevs, but is
never reset at the start of each iteration. Since do_remove is
OR-accumulated across iterations, a positive result from one mdev
carries over to subsequent mdevs.

The fix is to set the do_remove flag with the first call to bitmap_and;
for example: do_remove = bitmap_an rather than do_remove |= bitmap_and.

Fixes: eeb386aeb5 ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 16:04:32 +02:00
Anthony Krowiak
4400270ec0 s390/vfio-ap: fix stale pqap_hook pointer on error in vfio_ap_mdev_set_kvm()
In vfio_ap_mdev_set_kvm(), kvm->arch.crypto.pqap_hook is set to
&matrix_mdev->pqap_hook before the update locks are acquired and the
mdev list is checked for a conflicting assignment. If another mdev is
already attached to the same KVM instance, the function returns -EPERM
without restoring the hook pointer, leaving kvm->arch.crypto.pqap_hook
pointing at the failing matrix_mdev instead of the mdev that legitimately
owns the KVM.

Since matrix_mdev->kvm is never set on this error path,
vfio_ap_mdev_unset_kvm() will not clean up the hook when matrix_mdev
is later closed. If matrix_mdev is subsequently freed, any PQAP
instruction executed by the guest will dereference the stale pointer
through pqap_hook_rwsem, resulting in a use-after-free.

Since kvm->arch.crypto.pqap_hook is only set in the vfio_ap_mdev_set_kvm()
function and is cleared in the vfio_ap_mdev_unset_kvm() function, a check
for 'kvm->arch.crypto.pqap_hook != NULL' is all that is needed to determine
whether it belongs to another mdev. This will alleviate the need to iterate
the matrix_dev->mdev_list list to see if the kvm object is assigned to
another mdev.This was introduced in v3 to alleviate the need to take the
mdevs_lock while iterating the list; however, this did not prevent a
potential race condition.

The pqap_hook_rwsem(write) is now performed inside
get_update_locks_for_kvm(), which is updated to acquire
pqap_hook_rwsem(write) between kvm->lock and mdevs_lock. This ordering
is consistent with the PQAP intercept path, which acquires pqap_hook_rwsem
in read mode while srcu is held under vcpu->mutex, establishing the
dependency: kvm->lock -> vcpu->mutex -> srcu -> pqap_hook_rwsem(read).

The pqap_hook_rwsem is now released inside the
release_update_locks_for_kvm(), which is updated to release
pqap_hook_rwsem(write) between mdevs_lock and kvm->lock.

Additionally, kvm_put_kvm() in vfio_ap_mdev_unset_kvm() is moved
after release_update_locks_for_kvm(). Previously it was called while
kvm->lock was held; if it were ever the last reference, kvm_destroy_vm()
would run under kvm->lock, which would deadlock.

Fixes: 86956e7076 ("s390/vfio-ap: replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification")
Cc: stable@vger.kernel.org
Co-developed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260806173435.105044-1-akrowiak@linux.ibm.com>
2026-08-11 10:45:27 +02:00
Finn Callies
0de29a313c s390/ap: Fix MAPML computation
When the TAPQ subfunction of PQAP returns a value between 0 and 3 in the
ml field, the Principles of Operation states that the Maximum AP Message
Length (MAPML) must be 12 KB.

The previous code incorrectly calculated smaller sizes for ml values 1-2:
- ml=1: 4 KB instead of 12 KB
- ml=2: 8 KB instead of 12 KB

While no current hardware reports ml=1 or ml=2, this fix ensures correct
behavior for specification compliance and future-proofing.

The fix ensures all ml values 0-3 correctly use the 12 KB default, with
only values 4+ using the formula ml * 4096.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Finn Callies <fcallies@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Harald Freudenberger
eb36325447 s390/zcrypt: Pad trailing CCA or EP11 message with zeros
The both functions xcrb_msg_to_type6cprb_msgx() and
xcrb_msg_to_type6_ep11cprb_msgx() copy the user space message into a
kernel buffer based on the message length. But on further processing
the message is supposed to be 4 byte length adjusted. Thus up to 3
bytes of uninitialized kernel memory are forwarded to further
processing steps and may unwanted expose kernel memory to the crypto
card firmware.

This patch contains code to pad the gap between user space copied
message and message buffer length sent down to further processing of
the CCA or EP11 message to zeros.

Fixes: e2c6d91eb8 ("s390/zcrypt: Rework domain processing within zcrypt device driver")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 7.1+
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:12:22 +02:00
Harald Freudenberger
0864a16378 s390/zcrypt: Improve EP11 CPRB domain handling with ASN.1 parsing
The zcrypt_msgtype6_send_ep11_cprb() function uses fragile struct
overlays to access and modify the domain field in the EP11 CPRB
payload, creating maintainability and security concerns:
1. Struct overlay approach (pld_hdr) assumes fixed payload structure
   and doesn't validate the actual ASN.1 encoding.
2. Complex length format detection logic is error-prone and doesn't
   properly validate bounds at each parsing step.
3. Direct struct member access bypasses proper ASN.1 validation.

Fix by replacing struct overlays with explicit ASN.1 parsing that
validates each field (payload tag/length, function tag/length/value,
optional domain tag/length/value) with proper bounds checking at every
step. Add asn1_int_encode() helper function to safely write integer
values with correct endianness conversion. This makes the code
consistent with the validation pattern introduced with the rework of
the xcrb_msg_to_type6_ep11cprb_msgx() function.

Fixes: e2c6d91eb8 ("s390/zcrypt: Rework domain processing within zcrypt device driver")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Cc: stable@vger.kernel.org # 7.1+
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:12:22 +02:00
Harald Freudenberger
17ac0bc866 s390/zcrypt: Improve EP11 CPRB length and overflow checks
The xcrb_msg_to_type6_ep11cprb_msgx() function lacks proper input
validation, creating security vulnerabilities:
1. Missing minimum size validation: The ep11_cprb structure and
   subsequent payload fields (pld_tag, pld_lenfmt) are copied from
   userspace without verifying sufficient buffer length.
2. Arithmetic overflow in length calculations: CEIL4 alignment could
   overflow, bypassing size checks and enabling buffer overflows.
3. The payload is asn1 encoded but the function just uses a simple c
   struct overlay to access some fields of the payload.

Fix by using size_t for length calculations, adding U32_MAX boundary
checks after alignment, and validating minimum request size and
minimum reply size before copying from userspace. Do a very simple
asn1 parsing of the payload up to the function value field.

Fixes: e2c6d91eb8 ("s390/zcrypt: Rework domain processing within zcrypt device driver")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Cc: stable@vger.kernel.org # 7.1+
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:12:22 +02:00
Harald Freudenberger
35ac6754ba s390/zcrypt: Improve CCA CPRB length and overflow checks
The xcrb_msg_to_type6cprb_msgx() function lacks proper input
validation, creating security vulnerabilities:
1. Integer overflow after CEIL4 alignment: Signed int variables could
   overflow during 4-byte boundary alignment, causing undersized
   buffer allocations or incorrect bounds checking.
2. Missing minimum size validation: The CPRBX structure is copied from
   userspace without verifying sufficient buffer length. Undersized
   buffers cause uninitialized memory access when reading structure
   fields like cprbx.cprb_len and cprbx.domain.
3. Arithmetic overflow in sum calculations: Adding control block and
   data block sizes could overflow, bypassing size checks and enabling
   buffer overflows.

Fix by using size_t for length calculations, adding U32_MAX boundary
checks after alignment, validating minimum control block size before
copying from userspace, and detecting sum calculation overflows.

Fixes: e2c6d91eb8 ("s390/zcrypt: Rework domain processing within zcrypt device driver")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 7.1+
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:12:22 +02:00
Harald Freudenberger
5004889551 s390/zcrypt: Fix CPRB memory allocation in zcrypt misc code
Both CPRB alloc functions in zcrypt_ccamisc.c and zcrypt_ep11misc.c
did not round up the memory allocation to a multiple of 4 bytes as it
is needed by the zcrypt layer to process the CPRBs.

Now the alloc_and_prep_cprbmem() and alloc_cprbmem() functions
guarantee that the base CPRB struct and a possible parameter block are
aligned to a 4-byte boundary and the backing memory allocation is
rounded up to the next multiple of 4 byte. Also the free_cprbmem() is
updated and scrubs the rounded up amount of memory.

Fixes: 9bdb5f7e83 ("s390/zcrypt: Introduce cprb mempool for cca misc functions")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 6.16+
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:12:22 +02:00
Finn Callies
bdce129e44 s390/ap: Fix queue depth field length
The queue depth field is defined as a 5 bit field in the Z architecture
instead of a 4 bit field.

The queue depth (qd) can be in range 0-31 and is reported in bits 59-63
of the TAPQ response. Currently this has no effect as all CEX generations
report a queue depth of 7, which fits into 4 bits. However, future CEX
generations reporting a value >15 would not be properly reflected by the
ap bus and therefore all user space applications relying on it.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:30 +02:00
Harald Freudenberger
01476391ae s390/zcrypt: Fix missing mem scrub at clear key import in cca_clr2cipherkey()
The helper function _ip_cprb_helper() uses internal buffer memory for
building and processing CPRBs. After use this buffer was never
scrubbed which could lead to leaving for example clear key material in
memory which could be exposed via tricky reuse of this same memory.

Extend the _ip_cprb_helper() function with another parameter 'scrub'
used to steer scrubbing of this buffer. So now the caller has the
opportunity to decide if scrubbing is needed or not.

Extend the clear key to secure key token import process in function
cca_clr2cipherkey() to tell the helper function from above to scrub
the cprb buffer when the clear key value is part of the request data.

Add explicit scrubbing on return from function cca_clr2cipherkey() for
the random EXOR buffer and the cprb buffer.

Overall this cleans the internal used buffer in case of clear key
import to prevent sensitive data to get exposed.

Fixes: 4bc123b18c ("s390/zcrypt: Add low level functions for CCA AES cipher keys")
Cc: stable@vger.kernel.org
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:20 +02:00
Harald Freudenberger
e935cd525a s390/zcrypt: Close speculative mem read possibility
The domain value is extracted from a given CCA or EP11 ioctl struct
when a CPRB is about to be sent. Thus this is a user controlled value.
Under some special conditions (custom device node used, administrative
load) this value is used as an array index after bounds checking, but
without speculation barrier.

Add the missing array_index_nospec() call to prevent speculative
execution where this domain value is used.

Fixes: cfd68b3309 ("s390/zcrypt: Filter admin CPRBs on custom devices")
Cc: stable@vger.kernel.org
Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:19 +02:00
Harald Freudenberger
983279d7f8 s390/zcrypt: Fix wrong domain value verification with EP11 CPRBs
There is a wrong upper limit check for the domain value when an EP11
CPRB is processed for sending to a crypto card. This check is only
active on custom device nodes but may lead to access heap memory
behind perms->adm when an administrative CPRB is sent.
Add correct limit (AP_DOMAINS = 256) checking to fix this.

Fixes: cfd68b3309 ("s390/zcrypt: Filter admin CPRBs on custom devices")
Cc: stable@vger.kernel.org
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:19 +02:00
Harald Freudenberger
36b230835b s390/zcrypt: Fix buffer over-read in cca_cipher2protkey
Add validation of both the actual key buffer size and token length
fields in all the cca_check_sec*token() functions. Additionally check
in cca_gencipherkey() for possible underflow with returned key size.

The CCA token structures contain user-controlled len fields that
were used in operations without proper validation against both the
actual buffer size and minimum token structure size. An attacker
could set this field larger than the actual buffer size, leading to
reading beyond buffer boundaries. This may result in a kernel crash or
exposure of memory via sending this as part of a request down to the
crypto card. Also an attacker could have used a very small len value
and thus enforce a buffer under-run which may produce similar effects
as a over-read.

So now a key must
- key buf length must be at least sizeof the token struct
- the key len field inside the token must fit into the range of
  sizeof key token struct ... key buf length

Fixes: 4bc123b18c ("s390/zcrypt: Add low level functions for CCA AES cipher keys")
Cc: stable@vger.kernel.org
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:19 +02:00
Holger Dengler
a9ae0f6dd4 s390/zcrypt: Validate length for CCA ECC private key requests
cca_ecc2protkey() derives the copy length for the CPRB parameter
block directly from the length field in the key token. Reject the
request early if the token length exceeds the available space in the
parameter block.

Fixes: fa6999e326 ("s390/pkey: support CCA and EP11 secure ECC private keys")
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 5.10+
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:19 +02:00
Holger Dengler
06afe425d5 s390/zcrypt: Validate length for CCA AES cipher key requests
cca_cipher2protkey() derives the copy length for the CPRB parameter
block directly from the length field in the key token. Reject the
request early if the token length exceeds the available space in the
parameter block.

Fixes: 4bc123b18c ("s390/zcrypt: Add low level functions for CCA AES cipher keys")
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 5.4+
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:19 +02:00
Harald Freudenberger
e6b197e8ec s390/pkey: Rework ioctl functions error paths
With the pkey rework there was the suggestion to rework the error and
free paths of the pkey ioctl functions. The complain was especially to
rewrite the failure handling with goto instead of all repeat the
nearly same code (kfree(), kfree_sensitive(), memzero_explicit()) for
each path. This patch removes all this duplicated code and introduces
one code block at the end of the functions which is jumped into via
goto out or executed on regular exit. As some helper functions return
an error pointer value (which is NOT NULL) make sure on the error path
there is not by accident kfree() or similar called on such ptr values.

Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:09 +02:00
Harald Freudenberger
2ba7ea7cb0 s390/ap: Use mutex_lock_killable() in ap_bus_force_rescan()
A deep dive into the AP bus code and zcrypt device driver about the
usage of mutex locking showed that there is one questionable call in
ap_bus.c in function ap_bus_force_rescan(). This function may be
called in kernel and process context. In both contexts only one info
is important: was there a AP bus scan running and did it result in
some updates on the AP devices. So only true/false is returned but no
info like -EINTR. But still the mutex lock call should be
interruptible to be able to kill a user space program blocked forever
on this. So this patch replaces mutex_lock_interruptible() with
mutex_lock_killable() to  be able to handle SIGKILL especially in user
space process context.

Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:08 +02:00
Rongguang Wei
575f87b9d4 s390/zcrypt: Remove the empty file
The files has no real user because CEX2 and CEX3 device drivers
are removed, also remove these empty files.

Fixes: 5ac8c72462 ("s390/zcrypt: remove CEX2 and CEX3 device drivers")
Signed-off-by: Rongguang Wei <weirongguang@kylinos.cn>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08 17:02:47 +02:00
Linus Torvalds
7404ce5163 s390 updates for 7.2-rc2
- Fix PKEY_VERIFYPROTK ioctl key type handling by removing the generic
   key-length based type check with its wrong bit-size calculation,
   and leaving protected key verification to the pkey handler
 
 - Fix monwriter buffer reuse by rejecting records that change the data
   length, preventing out of bounds user copy into the kernel buffer
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Merge tag 's390-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix PKEY_VERIFYPROTK ioctl key type handling by removing the generic
   key-length based type check with its wrong bit-size calculation, and
   leaving protected key verification to the pkey handler

 - Fix monwriter buffer reuse by rejecting records that change the data
   length, preventing out of bounds user copy into the kernel buffer

* tag 's390-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/monwriter: Reject buffer reuse with different data length
  pkey: Move keytype check from pkey api to handler
2026-07-04 06:28:45 -10:00
Uwe Kleine-König (The Capable Hub)
995832b2ce Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files)
Replace the #include of <linux/mod_devicetable.h> by the more specific
<linux/device-id/*.h> where applicable. For most cases the include
can be dropped completely, only a few drivers need one or two headers
added.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/1a3f2007c5c5dcf555c09a4035ce3ae8ef1b6c49.1782808461.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
2026-07-03 07:38:17 +02:00
Holger Dengler
754e9e49b7 pkey: Move keytype check from pkey api to handler
The PKEY_VERIFYPROTK ioctl takes data from user-space and verifies the
contained protected key. While checking the integrity of the ioctl
request structure is the responsibility of the generic pkey_api code,
the verification of the contained protected key is the responsibility
of the pkey handler.

The keytype verification (based on the calculated bitsize of the key)
is part of the protected key verification and therefore the
responsibility of the pkey handler (which already verifies
it). Therefore the keytype verification is removed from the generic
pkey_api code.

As the calculation of the key bitsize is currently wrong, the removal
of the keytype check in pkey_api also removes this wrong
calculation. For this reason, the commit is flagged with the Fixes:
tag.

Cc: stable@kernel.org # 6.12+
Fixes: 8fcc231ce3 ("s390/pkey: Introduce pkey base with handler registry and handler modules")
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-01 17:10:53 +02:00
Holger Dengler
1ac287e2af s390/pkey: Check length in pkey_pckmo handler implementation
Explicitly check the length of the target buffer in the pkey_pckmo
implementation of the key_to_protkey() handler function. The handler
function fails, if the generated output data exceeds the length of the
provided target buffer.

Cc: stable@vger.kernel.org
Fixes: 8fcc231ce3 ("s390/pkey: Introduce pkey base with handler registry and handler modules")
Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-19 14:51:08 +02:00
Holger Dengler
b3d4ab2d7d s390/pkey: Check length in PKEY_VERIFYPROTK ioctl
Explicitly check the buffer length request structure provided by
user-space and fail, if it exceeds the buffer size.

Cc: stable@vger.kernel.org
Fixes: 8fcc231ce3 ("s390/pkey: Introduce pkey base with handler registry and handler modules")
Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-19 14:51:08 +02:00
Harald Freudenberger
7ecac01cf1 s390/ap: Fix locking issue in SE bind and associate sysfs functions
Revisit and reorganize the locking and lock coverage of the
ap->lock spinlock as used in the two sysfs functions
se_bind_store() and se_associate_store().

A kernel run reported a possible deadlock situation, caused by
holding the spinlock (ap->lock) while triggering a uevent.
The fix rearranges the code protected by the spinlock by excluding
the uevent invocation, which does not require protection.

Additionally, the start of the protected region is moved earlier
to cover more lines, ensuring a consistent view of the AP queue
state between reading and updating its struct fields.

	=====================================================
	WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
	7.1.0-20260601.rc6.git12.516b5dbd4d4a.300.fc44.s390x+debug #1 Not tainted
	-----------------------------------------------------
	setupseguest.sh/11034 [HC0[0]:SC0[2]:HE1:SE0] is trying to acquire:
	000001c991f498e8 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x5a/0x6d0
	and this task is already holding:
	000000c4a1a12378 (&aq->lock){+.-.}-{2:2}, at: se_bind_store+0x96/0x3a0
	which would create a new lock dependency:
	 (&aq->lock){+.-.}-{2:2} -> (fs_reclaim){+.+.}-{0:0}
	but this new dependency connects a SOFTIRQ-irq-safe lock:
	 (&aq->lock){+.-.}-{2:2}
	... which became SOFTIRQ-irq-safe at:
	  __lock_acquire+0x5ae/0x15a0
	  lock_acquire+0x14c/0x400
	  _raw_spin_lock_bh+0x58/0xb0
	  ap_tasklet_fn+0x72/0xd0
	  tasklet_action_common+0x174/0x1b0
	  handle_softirqs+0x180/0x5c0
	  irq_exit_rcu+0x196/0x200
	  do_ext_irq+0x12a/0x4d0
	  ext_int_handler+0xc6/0xf0
	  folio_zero_user+0x1c6/0x240
	  folio_zero_user+0x182/0x240
	  vma_alloc_anon_folio_pmd+0xa0/0x1d0
	  __do_huge_pmd_anonymous_page+0x3a/0x200
	  __handle_mm_fault+0x56c/0x590
	  handle_mm_fault+0xa2/0x370
	  do_exception+0x292/0x590
	  __do_pgm_check+0x136/0x3e0
	  pgm_check_handler+0x114/0x160
	to a SOFTIRQ-irq-unsafe lock:
	 (fs_reclaim){+.+.}-{0:0}
	... which became SOFTIRQ-irq-unsafe at:
	...
	  __lock_acquire+0x5ae/0x15a0
	  lock_acquire+0x14c/0x400
	  __fs_reclaim_acquire+0x44/0x50
	  fs_reclaim_acquire+0xbe/0x100
	  fs_reclaim_correct_nesting+0x20/0x70
	  dotest+0x5e/0x148
	  locking_selftest+0x2854/0x2a88
	  start_kernel+0x3b2/0x4f0
	  startup_continue+0x2e/0x40
	other info that might help us debug this:
	 Possible interrupt unsafe locking scenario:
	       CPU0                    CPU1
	       ----                    ----
	  lock(fs_reclaim);
				       local_irq_disable();
				       lock(&aq->lock);
				       lock(fs_reclaim);
	  <Interrupt>
	    lock(&aq->lock);
	 *** DEADLOCK ***
	4 locks held by setupseguest.sh/11034:
	 #0: 000000c485d01440 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x2fc/0x380
	 #1: 000000c4d2283288 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x12a0x270
	 #2: 000000c4a1830e48 (kn->active#172){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1e/0x270
	 #3: 000000c4a1a12378 (&aq->lock){+.-.}-{2:2}, at: se_bind_store+0x96/0x3a0
	the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
	-> (&aq->lock){+.-.}-{2:2} {
	   HARDIRQ-ON-W at:
			    __lock_acquire+0x5ae/0x15a0
			    lock_acquire+0x14c/0x400
			    _raw_spin_lock_bh+0x58/0xb0
			    ap_queue_init_state+0x2e/0x50
			    ap_scan_domains+0x5d6/0x620
			    ap_scan_adapter+0x4c0/0x810
			    ap_scan_bus+0x70/0x350
			    ap_scan_bus_wq_callback+0x56/0x80
			    process_one_work+0x2ba/0x820
			    worker_thread+0x21a/0x400
			    kthread+0x164/0x190
			    __ret_from_fork+0x4c/0x340
			    ret_from_fork+0xa/0x30
	   IN-SOFTIRQ-W at:
			    __lock_acquire+0x5ae/0x15a0
			    lock_acquire+0x14c/0x400
			    _raw_spin_lock_bh+0x58/0xb0
			    ap_tasklet_fn+0x72/0xd0
			    tasklet_action_common+0x174/0x1b0
			    handle_softirqs+0x180/0x5c0
			    irq_exit_rcu+0x196/0x200
			    do_ext_irq+0x12a/0x4d0
			    ext_int_handler+0xc6/0xf0
			    folio_zero_user+0x1c6/0x240
			    folio_zero_user+0x182/0x240
			    vma_alloc_anon_folio_pmd+0xa0/0x1d0
			    __do_huge_pmd_anonymous_page+0x3a/0x200
			    __handle_mm_fault+0x56c/0x590
			    handle_mm_fault+0xa2/0x370
			    do_exception+0x292/0x590
			    __do_pgm_check+0x136/0x3e0
			    pgm_check_handler+0x114/0x160
	   INITIAL USE at:
			   __lock_acquire+0x5ae/0x15a0
			   lock_acquire+0x14c/0x400
			   _raw_spin_lock_bh+0x58/0xb0
			   ap_queue_init_state+0x2e/0x50
			   ap_scan_domains+0x5d6/0x620
			   ap_scan_adapter+0x4c0/0x810
			   ap_scan_bus+0x70/0x350
			   ap_scan_bus_wq_callback+0x56/0x80
			   process_one_work+0x2ba/0x820
			   worker_thread+0x21a/0x400
			   kthread+0x164/0x190
			   __ret_from_fork+0x4c/0x340
			   ret_from_fork+0xa/0x30
	 }
	 ... key      at: [<000001c9936e8aa0>] __key.7+0x0/0x10
	the dependencies between the lock to be acquired
	 and SOFTIRQ-irq-unsafe lock:
	-> (fs_reclaim){+.+.}-{0:0} {
	   HARDIRQ-ON-W at:
			    __lock_acquire+0x5ae/0x15a0
			    lock_acquire+0x14c/0x400
			    __fs_reclaim_acquire+0x44/0x50
			    fs_reclaim_acquire+0xbe/0x100
			    fs_reclaim_correct_nesting+0x20/0x70
			    dotest+0x5e/0x148
			    locking_selftest+0x2854/0x2a88
			    start_kernel+0x3b2/0x4f0
			    startup_continue+0x2e/0x40
	   SOFTIRQ-ON-W at:
			    __lock_acquire+0x5ae/0x15a0
			    lock_acquire+0x14c/0x400
			    __fs_reclaim_acquire+0x44/0x50
			    fs_reclaim_acquire+0xbe/0x100
			    fs_reclaim_correct_nesting+0x20/0x70
			    dotest+0x5e/0x148
			    locking_selftest+0x2854/0x2a88
			    start_kernel+0x3b2/0x4f0
			    startup_continue+0x2e/0x40
	   INITIAL USE at:
			   __lock_acquire+0x5ae/0x15a0
			   lock_acquire+0x14c/0x400
			   __fs_reclaim_acquire+0x44/0x50
			   fs_reclaim_acquire+0xbe/0x100
			   fs_reclaim_correct_nesting+0x20/0x70
			   dotest+0x5e/0x148
			   locking_selftest+0x2854/0x2a88
			   start_kernel+0x3b2/0x4f0
			   startup_continue+0x2e/0x40
	 }
	 ... key      at: [<000001c991f498e8>] __fs_reclaim_map+0x0/0x30
	 ... acquired at:
	   check_prev_add+0x178/0xf40
	   __lock_acquire+0x12aa/0x15a0
	   lock_acquire+0x14c/0x400
	   __fs_reclaim_acquire+0x44/0x50
	   fs_reclaim_acquire+0xbe/0x100
	   __kmalloc_cache_noprof+0x5a/0x6d0
	   kobject_uevent_env+0xd4/0x420
	   ap_send_se_bind_uevent+0x48/0x70
	   se_bind_store+0x146/0x3a0
	   kernfs_fop_write_iter+0x18c/0x270
	   vfs_write+0x23c/0x380
	   ksys_write+0x88/0x120
	   __do_syscall+0x170/0x750
	   system_call+0x72/0x90
	stack backtrace:
	CPU: 6 UID: 0 PID: 11034 Comm: setupseguest.sh Not tainted 7.1.0-20260601.rc6.git2.516b5dbd4d4a.300.fc44.s390x+debug #1 PREEMPT
	Hardware name: IBM 9175 ME1 701 (KVM/Linux)
	Call Trace:
	 [<000001c98ffa0a7e>] dump_stack_lvl+0xae/0x108
	 [<000001c9900a6d7a>] print_bad_irq_dependency+0x47a/0x480
	 [<000001c9900a7184>] check_irq_usage+0x404/0x4c0
	 [<000001c9900a73b8>] check_prev_add+0x178/0xf40
	 [<000001c9900aaf1a>] __lock_acquire+0x12aa/0x15a0
	 [<000001c9900ab35c>] lock_acquire+0x14c/0x400
	 [<000001c9903be454>] __fs_reclaim_acquire+0x44/0x50
	 [<000001c9903be51e>] fs_reclaim_acquire+0xbe/0x100
	 [<000001c9903cf4ca>] __kmalloc_cache_noprof+0x5a/0x6d0
	 [<000001c9910ca9d4>] kobject_uevent_env+0xd4/0x420
	 [<000001c990d84098>] ap_send_se_bind_uevent+0x48/0x70
	 [<000001c990d87416>] se_bind_store+0x146/0x3a0
	 [<000001c99057da7c>] kernfs_fop_write_iter+0x18c/0x270
	 [<000001c99047712c>] vfs_write+0x23c/0x380
	 [<000001c990477438>] ksys_write+0x88/0x120
	 [<000001c9910f64e0>] __do_syscall+0x170/0x750
	 [<000001c99110a412>] system_call+0x72/0x90
	INFO: lockdep is turned off.

Fixes: 4179c39842 ("s390/ap: Implement SE bind and associate uevents")
Reported-by: Ingo Franzki <ifranzki@linux.ibm.com>
Suggested-by: Finn Callies <fcallies@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-09 19:33:00 +02:00
Mike Rapoport (Microsoft)
a2b94afeb5 s390/zcrypt: Replace get_zeroed_page() with kzalloc()
zcrypt_rng_device_add() allocates a buffer for the software random
number generator data cache.

This buffer can be allocated with kmalloc() as there's nothing special
about it to go directly to the page allocator.

kmalloc() provides a better API that does not require ugly casts and
kfree() does not need to know the size of the freed object.

Performance difference between kmalloc() and __get_free_pages() is not
measurable as both allocators take an object/page from a per-CPU list for
fast path allocations.

For the slow path the performance is anyway determined by the amount of
reclaim involved rather than by what allocator is used.

Replace use of get_zeroed_page() with kzalloc() and free_page() with
kfree().

Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-03 15:32:45 +02:00
Harald Freudenberger
7321674d06 s390/ap/zcrypt: Rearrange fields within AP and zcrypt structs
Rearrange some fields within AP and zcrypt structs to reduce
memory consumption and unused holes with the help of pahole
analysis of the code.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Finn Callies <fcallies@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-03 15:32:43 +02:00
Harald Freudenberger
4179c39842 s390/ap: Implement SE bind and associate uevents
Notify userspace about two important events on AP queues
when run within Secure Execution (SE) environment:
- Send AP CHANGE uevent with "SE_BIND=1" on successful bind
  operation on this AP queue device.
- Send AP CHANGE uevent with "SE_ASSOC=<association_index>"
  on successful association operation with the secret of the
  reported index on this AP queue device.

Note there is no SE unbind/unassociate event. Unbind/unassociate
can have different triggers and technically there is no signaling
done which the AP code could catch. A user space application can,
if this information is crucial, query the sysfs attribute se_bind
on the AP queue which runs a synchronous TAPQ. If the attribute
returns with "unbound" a reset took place and SE bind and associate
states are unbound and unassociated.

Suggested-by: Marc Hartmayer mhartmay@linux.ibm.com
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11 16:42:31 +02:00
Linus Torvalds
2a4c0c11c0 s390 updates for 7.1 merge window
- Add support for CONFIG_PAGE_TABLE_CHECK and enable it in
   debug_defconfig. s390 can only tell user from kernel PTEs via the mm,
   so mm_struct is now passed into pxx_user_accessible_page() callbacks
 
 - Expose the PCI function UID as an arch-specific slot attribute in
   sysfs so a function can be identified by its user-defined id while
   still in standby. Introduces a generic ARCH_PCI_SLOT_GROUPS hook in
   drivers/pci/slot.c
 
 - Refresh s390 PCI documentation to reflect current behavior and cover
   previously undocumented sysfs attributes
 
 - zcrypt device driver cleanup series: consistent field types, clearer
   variable naming, a kernel-doc warning fix, and a comment explaining
   the intentional synchronize_rcu() in pkey_handler_register()
 
 - Provide an s390 arch_raw_cpu_ptr() that avoids the detour via
   get_lowcore() using alternatives, shrinking defconfig by ~27 kB
 
 - Guard identity-base randomization with kaslr_enabled() so nokaslr
   keeps the identity mapping at 0 even with
   CONFIG_RANDOMIZE_IDENTITY_BASE=y
 
 - Build S390_MODULES_SANITY_TEST as a module only by requiring
   KUNIT && m, since built-in would not exercise module loading
 
 - Remove the permanently commented-out HMCDRV_DEV_CLASS create_class()
   code in the hmcdrv driver
 
 - Drop stale ident_map_size extern conflicting with asm/page.h
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Merge tag 's390-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for CONFIG_PAGE_TABLE_CHECK and enable it in
   debug_defconfig. s390 can only tell user from kernel PTEs via the mm,
   so mm_struct is now passed into pxx_user_accessible_page() callbacks

 - Expose the PCI function UID as an arch-specific slot attribute in
   sysfs so a function can be identified by its user-defined id while
   still in standby. Introduces a generic ARCH_PCI_SLOT_GROUPS hook in
   drivers/pci/slot.c

 - Refresh s390 PCI documentation to reflect current behavior and cover
   previously undocumented sysfs attributes

 - zcrypt device driver cleanup series: consistent field types, clearer
   variable naming, a kernel-doc warning fix, and a comment explaining
   the intentional synchronize_rcu() in pkey_handler_register()

 - Provide an s390 arch_raw_cpu_ptr() that avoids the detour via
   get_lowcore() using alternatives, shrinking defconfig by ~27 kB

 - Guard identity-base randomization with kaslr_enabled() so nokaslr
   keeps the identity mapping at 0 even with RANDOMIZE_IDENTITY_BASE=y

 - Build S390_MODULES_SANITY_TEST as a module only by requiring KUNIT &&
   m, since built-in would not exercise module loading

 - Remove the permanently commented-out HMCDRV_DEV_CLASS create_class()
   code in the hmcdrv driver

 - Drop stale ident_map_size extern conflicting with asm/page.h

* tag 's390-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/zcrypt: Fix warning about wrong kernel doc comment
  PCI: s390: Expose the UID as an arch specific PCI slot attribute
  docs: s390/pci: Improve and update PCI documentation
  s390/pkey: Add comment about synchronize_rcu() to pkey base
  s390/hmcdrv: Remove commented out code
  s390/zcrypt: Slight rework on the agent_id field
  s390/zcrypt: Explicitly use a card variable in _zcrypt_send_cprb
  s390/zcrypt: Rework MKVP fields and handling
  s390/zcrypt: Make apfs a real unsigned int field
  s390/zcrypt: Rework domain processing within zcrypt device driver
  s390/zcrypt: Move inline function rng_type6cprb_msgx from header to code
  s390/percpu: Provide arch_raw_cpu_ptr()
  s390: Enable page table check for debug_defconfig
  s390/pgtable: Add s390 support for page table check
  s390/pgtable: Use set_pmd_bit() to invalidate PMD entry
  mm/page_table_check: Pass mm_struct to pxx_user_accessible_page()
  s390/boot: Respect kaslr_enabled() for identity randomization
  s390/Kconfig: Make modules sanity test a module-only option
  s390/setup: Drop stale ident_map_size declaration
2026-04-22 11:13:45 -07:00
Linus Torvalds
4793dae01f Driver core changes for 7.1-rc1
- debugfs:
   - Fix NULL pointer dereference in debugfs_create_str()
   - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str()
   - Fix soundwire debugfs NULL pointer dereference from uninitialized
     firmware_file
 
 - device property:
   - Make fwnode flags modifications thread safe; widen the field to
     unsigned long and use set_bit() / clear_bit() based accessors
   - Document how to check for the property presence
 
 - devres:
   - Separate struct devres_node from its "subclasses" (struct devres,
     struct devres_group); give struct devres_node its own release and
     free callbacks for per-type dispatch
   - Introduce struct devres_action for devres actions, avoiding the
     ARCH_DMA_MINALIGN alignment overhead of struct devres
   - Export struct devres_node and its init/add/remove/dbginfo
     primitives for use by Rust Devres<T>
   - Fix missing node debug info in devm_krealloc()
   - Use guard(spinlock_irqsave) where applicable; consolidate unlock
     paths in devres_release_group()
 
 - driver_override:
   - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the
     generic driver_override infrastructure, replacing per-bus
     driver_override strings, sysfs attributes, and match logic; fixes
     a potential UAF from unsynchronized access to driver_override in
     bus match() callbacks
   - Simplify __device_set_driver_override() logic
 
 - kernfs:
   - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs
     file and directory removal
   - Add corresponding selftests for memcg
 
 - platform:
   - Allow attaching software nodes when creating platform devices via
     a new 'swnode' field in struct platform_device_info
   - Add kerneldoc for struct platform_device_info
 
 - software node:
   - Move software node initialization from postcore_initcall() to
     driver_init(), making it available early in the boot process
   - Move kernel_kobj initialization (ksysfs_init) earlier to support
     the above
   - Remove software_node_exit(); dead code in a built-in unit
 
 - SoC:
   - Introduce of_machine_read_compatible() and of_machine_read_model()
     OF helpers and export soc_attr_read_machine() to replace direct
     accesses to of_root from SoC drivers; also enables
     CONFIG_COMPILE_TEST coverage for these drivers
 
 - sysfs:
   - Constify attribute group array pointers to
     'const struct attribute_group *const *' in sysfs functions,
     device_add_groups() / device_remove_groups(), and struct class
 
 - Rust:
   - Devres:
     - Embed struct devres_node directly in Devres<T> instead of going
       through devm_add_action(), avoiding the extra allocation and
       the unnecessary ARCH_DMA_MINALIGN alignment
 
   - I/O:
     - Turn IoCapable from a marker trait into a functional trait
       carrying the raw I/O accessor implementation (io_read /
       io_write), providing working defaults for the per-type Io
       methods
     - Add RelaxedMmio wrapper type, making relaxed accessors usable
       in code generic over the Io trait
     - Remove overloaded per-type Io methods and per-backend macros
       from Mmio and PCI ConfigSpace
 
   - I/O (Register):
     - Add IoLoc trait and generic read/write/update methods to the Io
       trait, making I/O operations parameterizable by typed locations
     - Add register! macro for defining hardware register types with
       typed bitfield accessors backed by Bounded values; supports
       direct, relative, and array register addressing
     - Add write_reg() / try_write_reg() and LocatedRegister trait
     - Update PCI sample driver to demonstrate the register! macro
 
         Example:
 
         ```
             register! {
                 /// UART control register.
                 CTRL(u32) @ 0x18 {
                     /// Receiver enable.
                     19:19   rx_enable => bool;
                     /// Parity configuration.
                     14:13   parity ?=> Parity;
                 }
 
                 /// FIFO watermark and counter register.
                 WATER(u32) @ 0x2c {
                     /// Number of datawords in the receive FIFO.
                     26:24   rx_count;
                     /// RX interrupt threshold.
                     17:16   rx_water;
                 }
             }
 
             impl WATER {
                 fn rx_above_watermark(&self) -> bool {
                     self.rx_count() > self.rx_water()
                 }
             }
 
             fn init(bar: &pci::Bar<BAR0_SIZE>) {
                 let water = WATER::zeroed()
                     .with_const_rx_water::<1>(); // > 3 would not compile
                 bar.write_reg(water);
 
                 let ctrl = CTRL::zeroed()
                     .with_parity(Parity::Even)
                     .with_rx_enable(true);
                 bar.write_reg(ctrl);
             }
 
             fn handle_rx(bar: &pci::Bar<BAR0_SIZE>) {
                 if bar.read(WATER).rx_above_watermark() {
                     // drain the FIFO
                 }
             }
 
             fn set_parity(bar: &pci::Bar<BAR0_SIZE>, parity: Parity) {
                 bar.update(CTRL, |r| r.with_parity(parity));
             }
         ```
 
   - IRQ:
     - Move 'static bounds from where clauses to trait declarations
       for IRQ handler traits
 
   - Misc:
     - Enable the generic_arg_infer Rust feature
     - Extend Bounded with shift operations, single-bit bool conversion,
       and const get()
 
 - Misc:
   - Make deferred_probe_timeout default a Kconfig option
   - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM
     callbacks when no bus type PM ops are set
   - Add conditional guard support for device_lock()
   - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry
   - Fix kernel-doc warnings in base.h
   - Fix stale reference to memory_block_add_nid() in documentation
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Merge tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Fix NULL pointer dereference in debugfs_create_str()
   - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str()
   - Fix soundwire debugfs NULL pointer dereference from uninitialized
     firmware_file

  device property:
   - Make fwnode flags modifications thread safe; widen the field to
     unsigned long and use set_bit() / clear_bit() based accessors
   - Document how to check for the property presence

  devres:
   - Separate struct devres_node from its "subclasses" (struct devres,
     struct devres_group); give struct devres_node its own release and
     free callbacks for per-type dispatch
   - Introduce struct devres_action for devres actions, avoiding the
     ARCH_DMA_MINALIGN alignment overhead of struct devres
   - Export struct devres_node and its init/add/remove/dbginfo
     primitives for use by Rust Devres<T>
   - Fix missing node debug info in devm_krealloc()
   - Use guard(spinlock_irqsave) where applicable; consolidate unlock
     paths in devres_release_group()

  driver_override:
   - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the
     generic driver_override infrastructure, replacing per-bus
     driver_override strings, sysfs attributes, and match logic; fixes a
     potential UAF from unsynchronized access to driver_override in bus
     match() callbacks
   - Simplify __device_set_driver_override() logic

  kernfs:
   - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file
     and directory removal
   - Add corresponding selftests for memcg

  platform:
   - Allow attaching software nodes when creating platform devices via a
     new 'swnode' field in struct platform_device_info
   - Add kerneldoc for struct platform_device_info

  software node:
   - Move software node initialization from postcore_initcall() to
     driver_init(), making it available early in the boot process
   - Move kernel_kobj initialization (ksysfs_init) earlier to support
     the above
   - Remove software_node_exit(); dead code in a built-in unit

  SoC:
   - Introduce of_machine_read_compatible() and of_machine_read_model()
     OF helpers and export soc_attr_read_machine() to replace direct
     accesses to of_root from SoC drivers; also enables
     CONFIG_COMPILE_TEST coverage for these drivers

  sysfs:
   - Constify attribute group array pointers to
     'const struct attribute_group *const *' in sysfs functions,
     device_add_groups() / device_remove_groups(), and struct class

  Rust:
   - Devres:
      - Embed struct devres_node directly in Devres<T> instead of going
        through devm_add_action(), avoiding the extra allocation and the
        unnecessary ARCH_DMA_MINALIGN alignment

   - I/O:
      - Turn IoCapable from a marker trait into a functional trait
        carrying the raw I/O accessor implementation (io_read /
        io_write), providing working defaults for the per-type Io
        methods
      - Add RelaxedMmio wrapper type, making relaxed accessors usable in
        code generic over the Io trait
      - Remove overloaded per-type Io methods and per-backend macros
        from Mmio and PCI ConfigSpace

   - I/O (Register):
      - Add IoLoc trait and generic read/write/update methods to the Io
        trait, making I/O operations parameterizable by typed locations
      - Add register! macro for defining hardware register types with
        typed bitfield accessors backed by Bounded values; supports
        direct, relative, and array register addressing
      - Add write_reg() / try_write_reg() and LocatedRegister trait
      - Update PCI sample driver to demonstrate the register! macro

         Example:

         ```
             register! {
                 /// UART control register.
                 CTRL(u32) @ 0x18 {
                     /// Receiver enable.
                     19:19   rx_enable => bool;
                     /// Parity configuration.
                     14:13   parity ?=> Parity;
                 }

                 /// FIFO watermark and counter register.
                 WATER(u32) @ 0x2c {
                     /// Number of datawords in the receive FIFO.
                     26:24   rx_count;
                     /// RX interrupt threshold.
                     17:16   rx_water;
                 }
             }

             impl WATER {
                 fn rx_above_watermark(&self) -> bool {
                     self.rx_count() > self.rx_water()
                 }
             }

             fn init(bar: &pci::Bar<BAR0_SIZE>) {
                 let water = WATER::zeroed()
                     .with_const_rx_water::<1>(); // > 3 would not compile
                 bar.write_reg(water);

                 let ctrl = CTRL::zeroed()
                     .with_parity(Parity::Even)
                     .with_rx_enable(true);
                 bar.write_reg(ctrl);
             }

             fn handle_rx(bar: &pci::Bar<BAR0_SIZE>) {
                 if bar.read(WATER).rx_above_watermark() {
                     // drain the FIFO
                 }
             }

             fn set_parity(bar: &pci::Bar<BAR0_SIZE>, parity: Parity) {
                 bar.update(CTRL, |r| r.with_parity(parity));
             }
         ```

   - IRQ:
      - Move 'static bounds from where clauses to trait declarations for
        IRQ handler traits

   - Misc:
      - Enable the generic_arg_infer Rust feature
      - Extend Bounded with shift operations, single-bit bool
        conversion, and const get()

  Misc:
   - Make deferred_probe_timeout default a Kconfig option
   - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM
     callbacks when no bus type PM ops are set
   - Add conditional guard support for device_lock()
   - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry
   - Fix kernel-doc warnings in base.h
   - Fix stale reference to memory_block_add_nid() in documentation"

* tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits)
  bus: fsl-mc: use generic driver_override infrastructure
  s390/ap: use generic driver_override infrastructure
  s390/cio: use generic driver_override infrastructure
  vdpa: use generic driver_override infrastructure
  platform/wmi: use generic driver_override infrastructure
  PCI: use generic driver_override infrastructure
  driver core: make software nodes available earlier
  software node: remove software_node_exit()
  kernel: ksysfs: initialize kernel_kobj earlier
  MAINTAINERS: add ksysfs.c to the DRIVER CORE entry
  drivers/base/memory: fix stale reference to memory_block_add_nid()
  device property: Document how to check for the property presence
  soundwire: debugfs: initialize firmware_file to empty string
  debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str()
  debugfs: check for NULL pointer in debugfs_create_str()
  driver core: Make deferred_probe_timeout default a Kconfig option
  driver core: simplify __device_set_driver_override() clearing logic
  driver core: auxiliary bus: Drop auxiliary_dev_pm_ops
  device property: Make modifications of fwnode "flags" thread safe
  rust: devres: embed struct devres_node directly
  ...
2026-04-13 19:03:11 -07:00
Harald Freudenberger
8d7ea40011 s390/zcrypt: Fix warning about wrong kernel doc comment
Fix this warning:
  Warning: drivers/s390/crypto/zcrypt_msgtype6.c:1253 This comment
  starts with '/**', but isn't a kernel-doc comment. Refer to
  Documentation/doc-guide/kernel-doc.rst

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603252022.vEojGo3V-lkp@intel.com/
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-04-11 11:18:15 +02:00
Danilo Krummrich
81d6f7c3a7 s390/ap: use generic driver_override infrastructure
When the AP masks are updated via apmask_store() or aqmask_store(),
ap_bus_revise_bindings() is called after ap_attr_mutex has been
released.

This calls __ap_revise_reserved(), which accesses the driver_override
field without holding any lock, racing against a concurrent
driver_override_store() that may free the old string, resulting in a
potential UAF.

Fix this by using the driver-core driver_override infrastructure, which
protects all accesses with an internal spinlock.

Note that unlike most other buses, the AP bus does not check
driver_override in its match() callback; the override is checked in
ap_device_probe() and __ap_revise_reserved() instead.

Also note that we do not enable the driver_override feature of struct
bus_type, as AP - in contrast to most other buses - passes "" to
sysfs_emit() when the driver_override pointer is NULL. Thus, printing
"\n" instead of "(null)\n".

Additionally, AP has a custom counter that is modified in the
corresponding custom driver_override_store().

Fixes: d38a87d7c0 ("s390/ap: Support driver_override for AP queue devices")
Tested-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Link: https://patch.msgid.link/20260324005919.2408620-11-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-04-04 00:49:22 +02:00
Harald Freudenberger
e3d074b5e6 s390/pkey: Add comment about synchronize_rcu() to pkey base
Add a comment about the use of the synchronize_rcu() invocation.
There are two invocations of the synchronize_rcu() call in the
pkey base code. On one place it is optional but used to enforce
a fast path update to the other CPUs. As some people and code
checkers complain about this redundant invocation the suggestion
came up to add a comment to explain why the call is meaningful
at that place.

Closes: https://lore.kernel.org/linux-s390/20260313052312.2389-1-lirongqing@baidu.com/
Suggested-by: Li Rongqing <lirongqing@baidu.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-04-02 12:06:29 +02:00
Harald Freudenberger
2a0a1db508 s390/zcrypt: Slight rework on the agent_id field
The agent_id field is a two byte ascii field addressing
the target agent on the crypto card. Some code however
addresses this field as unsigned short. Rework these
places to treat this field always as a two byte array.
Unfortunately this field also shows up as __u16 in
struct ica_xcRB as part of the zcrypt ioctl interface.
Leave this untouched as it would break the API.

There are two other places (func_id) where a byte array
gets assigned with hex values but in fact these are ascii
value. So replace these assignments with real ascii values
for more readability.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24 21:00:42 +01:00
Harald Freudenberger
0e72b785b6 s390/zcrypt: Explicitly use a card variable in _zcrypt_send_cprb
Use an explicit variable "card" for the card addressing in
function _zcrypt_send_cprb instead of the confusing field
"user_defined" from the ica_xcRB struct. This makes the code
somewhat cleaner and easier to understand.

Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24 21:00:42 +01:00
Harald Freudenberger
227a9197ba s390/zcrypt: Rework MKVP fields and handling
In general all MKVPs (Master Key Verification Pattern) are binary
data - usually some kind of shortened hash value e.g. sha256.
Some code parts however used some u64 type which made compares
a little bit easier. Anyway this is binary data and so all
fields related to MKVP are now u8[] and function parameters
use (const) u8 * now. The sysfs emit for the MKVPs also has
been adapted to first format the MKVP as hex string into a
buffer and then use %s with sysfs_emit_at() to generate the
sysfs output. The patch also include a simple whitespace fix.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24 21:00:42 +01:00
Harald Freudenberger
ecd2fd113e s390/zcrypt: Make apfs a real unsigned int field
Slight rework on the apfs field: Instead of unsigned char[4]
make this a real 32 bit unsigned int field. With that done,
some assignments and some printouts can be simplified.
With that comes a slight move of the anonymous struct covering
the message type 86 header to dedupe some code lines.

Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24 21:00:41 +01:00
Harald Freudenberger
e2c6d91eb8 s390/zcrypt: Rework domain processing within zcrypt device driver
Slight rework of the domain handling within the zcrypt dd:
Remove this curious construct to give a pointer to the
domain field within the CPRB struct to the zcrypt API and
later fill in the target domain via this pointer.
Now the domain is filled in with the send function when
the ready constructed AP message is about to be pushed
down into the software queue for AP queue processing.
So now the domain handling for CCA, EP11 and (internal) rng
CPRBs is the same. With this comes a slight reshuffle of the
code related to domain processing in the zcrypt API and the
message type 60 protocol implementation code.

Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24 21:00:41 +01:00