Commit graph

138 commits

Author SHA1 Message Date
Arnd Bergmann
1c790815cd x86/amd_nb: Fix compile-testing without CONFIG_AMD_NB
[ Upstream commit fce9642c765a18abd1db0339a7d832c29b68456a ]

node_to_amd_nb() is defined to NULL in non-AMD configs:

  drivers/platform/x86/amd/hsmp/plat.c: In function 'init_platform_device':
  drivers/platform/x86/amd/hsmp/plat.c:165:68: error: dereferencing 'void *' pointer [-Werror]
    165 |                 sock->root                      = node_to_amd_nb(i)->root;
        |                                                                    ^~
  drivers/platform/x86/amd/hsmp/plat.c:165:68: error: request for member 'root' in something not a structure or union

Users of the interface who also allow COMPILE_TEST will cause the above build
error so provide an inline stub to fix that.

  [ bp: Massage commit message. ]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20241029092329.3857004-1-arnd@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-17 13:23:57 +01:00
Sean Christopherson
f1e091e52c KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN
commit aa0d42cacf093a6fcca872edc954f6f812926a17 upstream.

Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y.  There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.

For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check).  Per the SDM:

  If the logical processor is operating with Intel PT enabled (if
  IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
  IA32_RTIT_CTL" VM-entry control must be 0.

On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit.  E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc.

Fixes: f99e3daf94ff ("KVM: x86: Add Intel PT virtualization work mode")
Cc: stable@vger.kernel.org
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
Message-ID: <20241101185031.1799556-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-17 13:20:51 +01:00
Baoquan He
69f47a131e x86/mm: Fix a kdump kernel failure on SME system when CONFIG_IMA_KEXEC=y
commit 8d9ffb2fe65a6c4ef114e8d4f947958a12751bbe upstream.

The kdump kernel is broken on SME systems with CONFIG_IMA_KEXEC=y enabled.
Debugging traced the issue back to

  b69a2afd5afc ("x86/kexec: Carry forward IMA measurement log on kexec").

Testing was previously not conducted on SME systems with CONFIG_IMA_KEXEC
enabled, which led to the oversight, with the following incarnation:

...
  ima: No TPM chip found, activating TPM-bypass!
  Loading compiled-in module X.509 certificates
  Loaded X.509 cert 'Build time autogenerated kernel key: 18ae0bc7e79b64700122bb1d6a904b070fef2656'
  ima: Allocated hash algorithm: sha256
  Oops: general protection fault, probably for non-canonical address 0xcfacfdfe6660003e: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0-rc2+ #14
  Hardware name: Dell Inc. PowerEdge R7425/02MJ3T, BIOS 1.20.0 05/03/2023
  RIP: 0010:ima_restore_measurement_list
  Call Trace:
   <TASK>
   ? show_trace_log_lvl
   ? show_trace_log_lvl
   ? ima_load_kexec_buffer
   ? __die_body.cold
   ? die_addr
   ? exc_general_protection
   ? asm_exc_general_protection
   ? ima_restore_measurement_list
   ? vprintk_emit
   ? ima_load_kexec_buffer
   ima_load_kexec_buffer
   ima_init
   ? __pfx_init_ima
   init_ima
   ? __pfx_init_ima
   do_one_initcall
   do_initcalls
   ? __pfx_kernel_init
   kernel_init_freeable
   kernel_init
   ret_from_fork
   ? __pfx_kernel_init
   ret_from_fork_asm
   </TASK>
  Modules linked in:
  ---[ end trace 0000000000000000 ]---
  ...
  Kernel panic - not syncing: Fatal exception
  Kernel Offset: disabled
  Rebooting in 10 seconds..

Adding debug printks showed that the stored addr and size of ima_kexec buffer
are not decrypted correctly like:

  ima: ima_load_kexec_buffer, buffer:0xcfacfdfe6660003e, size:0xe48066052d5df359

Three types of setup_data info

  — SETUP_EFI,
  - SETUP_IMA, and
  - SETUP_RNG_SEED

are passed to the kexec/kdump kernel. Only the ima_kexec buffer
experienced incorrect decryption. Debugging identified a bug in
early_memremap_is_setup_data(), where an incorrect range calculation
occurred due to the len variable in struct setup_data ended up only
representing the length of the data field, excluding the struct's size,
and thus leading to miscalculation.

Address a similar issue in memremap_is_setup_data() while at it.

  [ bp: Heavily massage. ]

Fixes: b3c72fc9a78e ("x86/boot: Introduce setup_indirect")
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20240911081615.262202-3-bhe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-17 13:20:50 +01:00
Ksawlii
92c7fd94e3 Revert "x86/ibt,ftrace: Search for __fentry__ location"
This reverts commit f6f1a8e333.
2024-11-24 00:23:31 +01:00
Ksawlii
5fcfbc6d9d Revert "xen: use correct end address of kernel for conflict checking"
This reverts commit 5e2ec8dda3.
2024-11-24 00:23:24 +01:00
Ksawlii
ac6c389c56 Revert "x86/mm: Switch to new Intel CPU model defines"
This reverts commit d0b89ceba6.
2024-11-24 00:23:18 +01:00
Ksawlii
e998f5437f Revert "perf/x86/intel/pt: Fix sampling synchronization"
This reverts commit 8cfe7610cd.
2024-11-24 00:23:16 +01:00
Ksawlii
f6fecb09e8 Revert "x86/syscall: Avoid memcpy() for ia32 syscall_get_arguments()"
This reverts commit 23a2b0d100.
2024-11-24 00:23:07 +01:00
Ksawlii
f1cb82372f Revert "x86/resctrl: Annotate get_mem_config() functions as __init"
This reverts commit 8436a07c7a.
2024-11-24 00:22:51 +01:00
Ksawlii
57c42b3af7 Revert "x86/apic: Always explicitly disarm TSC-deadline timer"
This reverts commit 5a5d98e292.
2024-11-24 00:22:51 +01:00
Ksawlii
e19e6b3388 Revert "x86/entry_32: Do not clobber user EFLAGS.ZF"
This reverts commit 632fba79b9.
2024-11-24 00:22:51 +01:00
Ksawlii
5e83655d80 Revert "x86/entry_32: Clear CPU buffers after register restore in NMI return"
This reverts commit 0c7e61432d.
2024-11-24 00:22:51 +01:00
Pawan Gupta
9bae1af719 x86/bugs: Use code segment selector for VERW operand
commit e4d2102018542e3ae5e297bc6e229303abff8a0f upstream.

Robert Gill reported below #GP in 32-bit mode when dosemu software was
executing vm86() system call:

  general protection fault: 0000 [#1] PREEMPT SMP
  CPU: 4 PID: 4610 Comm: dosemu.bin Not tainted 6.6.21-gentoo-x86 #1
  Hardware name: Dell Inc. PowerEdge 1950/0H723K, BIOS 2.7.0 10/30/2010
  EIP: restore_all_switch_stack+0xbe/0xcf
  EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000
  ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: ff8affdc
  DS: 0000 ES: 0000 FS: 0000 GS: 0033 SS: 0068 EFLAGS: 00010046
  CR0: 80050033 CR2: 00c2101c CR3: 04b6d000 CR4: 000406d0
  Call Trace:
   show_regs+0x70/0x78
   die_addr+0x29/0x70
   exc_general_protection+0x13c/0x348
   exc_bounds+0x98/0x98
   handle_exception+0x14d/0x14d
   exc_bounds+0x98/0x98
   restore_all_switch_stack+0xbe/0xcf
   exc_bounds+0x98/0x98
   restore_all_switch_stack+0xbe/0xcf

This only happens in 32-bit mode when VERW based mitigations like MDS/RFDS
are enabled. This is because segment registers with an arbitrary user value
can result in #GP when executing VERW. Intel SDM vol. 2C documents the
following behavior for VERW instruction:

  #GP(0) - If a memory operand effective address is outside the CS, DS, ES,
	   FS, or GS segment limit.

CLEAR_CPU_BUFFERS macro executes VERW instruction before returning to user
space. Use %cs selector to reference VERW operand. This ensures VERW will
not #GP for an arbitrary user %ds.

[ mingo: Fixed the SOB chain. ]

Fixes: a0e2dab44d22 ("x86/entry_32: Add VERW just before userspace transition")
Reported-by: Robert Gill <rtgill82@gmail.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com
Cc: stable@vger.kernel.org # 5.10+
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218707
Closes: https://lore.kernel.org/all/8c77ccfd-d561-45a1-8ed5-6b75212c7a58@leemhuis.info/
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Suggested-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:22:06 +01:00
Sean Christopherson
5007c03ef5 KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory
commit f559b2e9c5c5308850544ab59396b7d53cfc67bd upstream.

Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits
4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't
enforce 32-byte alignment of nCR3.

In the absolute worst case scenario, failure to ignore bits 4:0 can result
in an out-of-bounds read, e.g. if the target page is at the end of a
memslot, and the VMM isn't using guard pages.

Per the APM:

  The CR3 register points to the base address of the page-directory-pointer
  table. The page-directory-pointer table is aligned on a 32-byte boundary,
  with the low 5 address bits 4:0 assumed to be 0.

And the SDM's much more explicit:

  4:0    Ignored

Note, KVM gets this right when loading PDPTRs, it's only the nSVM flow
that is broken.

Fixes: e4e517b4be01 ("KVM: MMU: Do not unconditionally read PDPTE from guest memory")
Reported-by: Kirk Swidowski <swidowski@google.com>
Cc: Andy Nguyen <theflow@google.com>
Cc: 3pvd <3pvd@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20241009140838.1036226-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:22:01 +01:00
Pawan Gupta
0c7e61432d x86/entry_32: Clear CPU buffers after register restore in NMI return
commit 48a2440d0f20c826b884e04377ccc1e4696c84e9 upstream.

CPU buffers are currently cleared after call to exc_nmi, but before
register state is restored. This may be okay for MDS mitigation but not for
RDFS. Because RDFS mitigation requires CPU buffers to be cleared when
registers don't have any sensitive data.

Move CLEAR_CPU_BUFFERS after RESTORE_ALL_NMI.

Fixes: a0e2dab44d22 ("x86/entry_32: Add VERW just before userspace transition")
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240925-fix-dosemu-vm86-v7-2-1de0daca2d42%40linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:57 +01:00
Pawan Gupta
632fba79b9 x86/entry_32: Do not clobber user EFLAGS.ZF
commit 2e2e5143d4868163d6756c8c6a4d28cbfa5245e5 upstream.

Opportunistic SYSEXIT executes VERW to clear CPU buffers after user EFLAGS
are restored. This can clobber user EFLAGS.ZF.

Move CLEAR_CPU_BUFFERS before the user EFLAGS are restored. This ensures
that the user EFLAGS.ZF is not clobbered.

Closes: https://lore.kernel.org/lkml/yVXwe8gvgmPADpRB6lXlicS2fcHoV5OHHxyuFbB_MEleRPD7-KhGe5VtORejtPe-KCkT8Uhcg5d7-IBw4Ojb4H7z5LQxoZylSmJ8KNL3A8o=@protonmail.com/
Fixes: a0e2dab44d22 ("x86/entry_32: Add VERW just before userspace transition")
Reported-by: Jari Ruusu <jariruusu@protonmail.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240925-fix-dosemu-vm86-v7-1-1de0daca2d42%40linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:57 +01:00
Zhang Rui
5a5d98e292 x86/apic: Always explicitly disarm TSC-deadline timer
commit ffd95846c6ec6cf1f93da411ea10d504036cab42 upstream.

New processors have become pickier about the local APIC timer state
before entering low power modes. These low power modes are used (for
example) when you close your laptop lid and suspend. If you put your
laptop in a bag and it is not in this low power mode, it is likely
to get quite toasty while it quickly sucks the battery dry.

The problem boils down to some CPUs' inability to power down until the
CPU recognizes that the local APIC timer is shut down. The current
kernel code works in one-shot and periodic modes but does not work for
deadline mode. Deadline mode has been the supported and preferred mode
on Intel CPUs for over a decade and uses an MSR to drive the timer
instead of an APIC register.

Disable the TSC Deadline timer in lapic_timer_shutdown() by writing to
MSR_IA32_TSC_DEADLINE when in TSC-deadline mode. Also avoid writing
to the initial-count register (APIC_TMICT) which is ignored in
TSC-deadline mode.

Note: The APIC_LVTT|=APIC_LVT_MASKED operation should theoretically be
enough to tell the hardware that the timer will not fire in any of the
timer modes. But mitigating AMD erratum 411[1] also requires clearing
out APIC_TMICT. Solely setting APIC_LVT_MASKED is also ineffective in
practice on Intel Lunar Lake systems, which is the motivation for this
change.

1. 411 Processor May Exit Message-Triggered C1E State Without an Interrupt if Local APIC Timer Reaches Zero - https://www.amd.com/content/dam/amd/en/documents/archived-tech-docs/revision-guides/41322_10h_Rev_Gd.pdf

Fixes: 279f1461432c ("x86: apic: Use tsc deadline for oneshot when available")
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: Todd Brandt <todd.e.brandt@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20241015061522.25288-1-rui.zhang%40intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:57 +01:00
Nathan Chancellor
8436a07c7a x86/resctrl: Annotate get_mem_config() functions as __init
commit d5fd042bf4cfb557981d65628e1779a492cd8cfa upstream.

After a recent LLVM change [1] that deduces __cold on functions that only call
cold code (such as __init functions), there is a section mismatch warning from
__get_mem_config_intel(), which got moved to .text.unlikely. as a result of
that optimization:

  WARNING: modpost: vmlinux: section mismatch in reference: \
  __get_mem_config_intel+0x77 (section: .text.unlikely.) -> thread_throttle_mode_init (section: .init.text)

Mark __get_mem_config_intel() as __init as well since it is only called
from __init code, which clears up the warning.

While __rdt_get_mem_config_amd() does not exhibit a warning because it
does not call any __init code, it is a similar function that is only
called from __init code like __get_mem_config_intel(), so mark it __init
as well to keep the code symmetrical.

CONFIG_SECTION_MISMATCH_WARN_ONLY=n would turn this into a fatal error.

Fixes: 05b93417ce5b ("x86/intel_rdt/mba: Add primary support for Memory Bandwidth Allocation (MBA)")
Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: <stable@kernel.org>
Link: 6b11573b8c [1]
Link: https://lore.kernel.org/r/20240917-x86-restctrl-get_mem_config_intel-init-v3-1-10d521256284@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:57 +01:00
Johannes Wikner
7550b4d26a x86/bugs: Do not use UNTRAIN_RET with IBPB on entry
commit c62fa117c32bd1abed9304c58e0da6940f8c7fc2 upstream.

Since X86_FEATURE_ENTRY_IBPB will invalidate all harmful predictions
with IBPB, no software-based untraining of returns is needed anymore.
Currently, this change affects retbleed and SRSO mitigations so if
either of the mitigations is doing IBPB and the other one does the
software sequence, the latter is not needed anymore.

  [ bp: Massage commit message. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Johannes Wikner <kwikner@ethz.ch>
Cc: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:55 +01:00
Johannes Wikner
d71cd4c6a9 x86/bugs: Skip RSB fill at VMEXIT
commit 0fad2878642ec46225af2054564932745ac5c765 upstream.

entry_ibpb() is designed to follow Intel's IBPB specification regardless
of CPU. This includes invalidating RSB entries.

Hence, if IBPB on VMEXIT has been selected, entry_ibpb() as part of the
RET untraining in the VMEXIT path will take care of all BTB and RSB
clearing so there's no need to explicitly fill the RSB anymore.

  [ bp: Massage commit message. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Johannes Wikner <kwikner@ethz.ch>
Cc: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:55 +01:00
Johannes Wikner
aaf7a8b6e6 x86/entry: Have entry_ibpb() invalidate return predictions
commit 50e4b3b94090babe8d4bb85c95f0d3e6b07ea86e upstream.

entry_ibpb() should invalidate all indirect predictions, including return
target predictions. Not all IBPB implementations do this, in which case the
fallback is RSB filling.

Prevent SRSO-style hijacks of return predictions following IBPB, as the return
target predictor can be corrupted before the IBPB completes.

  [ bp: Massage. ]

Signed-off-by: Johannes Wikner <kwikner@ethz.ch>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:55 +01:00
Johannes Wikner
dafb148361 x86/cpufeatures: Add a IBPB_NO_RET BUG flag
commit 3ea87dfa31a7b0bb0ff1675e67b9e54883013074 upstream.

Set this flag if the CPU has an IBPB implementation that does not
invalidate return target predictions. Zen generations < 4 do not flush
the RSB when executing an IBPB and this bug flag denotes that.

  [ bp: Massage. ]

Signed-off-by: Johannes Wikner <kwikner@ethz.ch>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:55 +01:00
Jim Mattson
f5f4b24070 x86/cpufeatures: Define X86_FEATURE_AMD_IBPB_RET
commit ff898623af2ed564300752bba83a680a1e4fec8d upstream.

AMD's initial implementation of IBPB did not clear the return address
predictor. Beginning with Zen4, AMD's IBPB *does* clear the return address
predictor. This behavior is enumerated by CPUID.80000008H:EBX.IBPB_RET[30].

Define X86_FEATURE_AMD_IBPB_RET for use in KVM_GET_SUPPORTED_CPUID,
when determining cross-vendor capabilities.

Suggested-by: Venkatesh Srinivas <venkateshs@chromium.org>
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:55 +01:00
Kees Cook
23a2b0d100 x86/syscall: Avoid memcpy() for ia32 syscall_get_arguments()
[ Upstream commit d19d638b1e6cf746263ef60b7d0dee0204d8216a ]

Modern (fortified) memcpy() prefers to avoid writing (or reading) beyond
the end of the addressed destination (or source) struct member:

In function ‘fortify_memcpy_chk’,
    inlined from ‘syscall_get_arguments’ at ./arch/x86/include/asm/syscall.h:85:2,
    inlined from ‘populate_seccomp_data’ at kernel/seccomp.c:258:2,
    inlined from ‘__seccomp_filter’ at kernel/seccomp.c:1231:3:
./include/linux/fortify-string.h:580:25: error: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning]
  580 |                         __read_overflow2_field(q_size_field, size);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

As already done for x86_64 and compat mode, do not use memcpy() to
extract syscall arguments from struct pt_regs but rather just perform
direct assignments. Binary output differences are negligible, and actually
ends up using less stack space:

-       sub    $0x84,%esp
+       sub    $0x6c,%esp

and less text size:

   text    data     bss     dec     hex filename
  10794     252       0   11046    2b26 gcc-32b/kernel/seccomp.o.stock
  10714     252       0   10966    2ad6 gcc-32b/kernel/seccomp.o.after

Closes: https://lore.kernel.org/lkml/9b69fb14-df89-4677-9c82-056ea9e706f5@gmail.com/
Reported-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Link: https://lore.kernel.org/all/20240708202202.work.477-kees%40kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:21:39 +01:00
Adrian Hunter
8cfe7610cd perf/x86/intel/pt: Fix sampling synchronization
commit d92792a4b26e50b96ab734cbe203d8a4c932a7a9 upstream.

pt_event_snapshot_aux() uses pt->handle_nmi to determine if tracing
needs to be stopped, however tracing can still be going because
pt->handle_nmi is set to zero before tracing is stopped in pt_event_stop,
whereas pt_event_snapshot_aux() requires that tracing must be stopped in
order to copy a sample of trace from the buffer.

Instead call pt_config_stop() always, which anyway checks config for
RTIT_CTL_TRACEEN and does nothing if it is already clear.

Note pt_event_snapshot_aux() can continue to use pt->handle_nmi to
determine if the trace needs to be restarted afterwards.

Fixes: 25e8920b301c ("perf/x86/intel/pt: Add sampling support")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20240715160712.127117-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:31 +01:00
Tony Luck
d0b89ceba6 x86/mm: Switch to new Intel CPU model defines
commit 2eda374e883ad297bd9fe575a16c1dc850346075 upstream.

New CPU #defines encode vendor and family as well as model.

[ dhansen: vertically align 0's in invlpg_miss_ids[] ]

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/all/20240424181518.41946-1-tony.luck%40intel.com
[ Ricardo: I used the old match macro X86_MATCH_INTEL_FAM6_MODEL()
  instead of X86_MATCH_VFM() as in the upstream commit.
  I also kept the ALDERLAKE_N name instead of ATOM_GRACEMONT. Both refer
  to the same CPU model. ]
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:29 +01:00
Juergen Gross
5e2ec8dda3 xen: use correct end address of kernel for conflict checking
[ Upstream commit fac1bceeeb04886fc2ee952672e6e6c85ce41dca ]

When running as a Xen PV dom0 the kernel is loaded by the hypervisor
using a different memory map than that of the host. In order to
minimize the required changes in the kernel, the kernel adapts its
memory map to that of the host. In order to do that it is checking
for conflicts of its load address with the host memory map.

Unfortunately the tested memory range does not include the .brk
area, which might result in crashes or memory corruption when this
area does conflict with the memory map of the host.

Fix the test by using the _end label instead of __bss_stop.

Fixes: 808fdb71936c ("xen: check for kernel memory conflicting with memory layout")

Signed-off-by: Juergen Gross <jgross@suse.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:21:22 +01:00
Peter Zijlstra
f6f1a8e333 x86/ibt,ftrace: Search for __fentry__ location
commit aebfd12521d9c7d0b502cf6d06314cfbcdccfe3b upstream.

Currently a lot of ftrace code assumes __fentry__ is at sym+0. However
with Intel IBT enabled the first instruction of a function will most
likely be ENDBR.

Change ftrace_location() to not only return the __fentry__ location
when called for the __fentry__ location, but also when called for the
sym+0 location.

Then audit/update all callsites of this function to consistently use
these new semantics.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154318.227581603@infradead.org
Stable-dep-of: e60b613df8b6 ("ftrace: Fix possible use-after-free issue in ftrace_location()")
[Shivani: Modified to apply on v5.10.y]
Signed-off-by: Shivani Agarwal <shivani.agarwal@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:16 +01:00
Michael Kelley
cda86a0cb1 x86/hyperv: Set X86_FEATURE_TSC_KNOWN_FREQ when Hyper-V provides frequency
[ Upstream commit 8fcc514809de41153b43ccbe1a0cdf7f72b78e7e ]

A Linux guest on Hyper-V gets the TSC frequency from a synthetic MSR, if
available. In this case, set X86_FEATURE_TSC_KNOWN_FREQ so that Linux
doesn't unnecessarily do refined TSC calibration when setting up the TSC
clocksource.

With this change, a message such as this is no longer output during boot
when the TSC is used as the clocksource:

[    1.115141] tsc: Refined TSC clocksource calibration: 2918.408 MHz

Furthermore, the guest and host will have exactly the same view of the
TSC frequency, which is important for features such as the TSC deadline
timer that are emulated by the Hyper-V host.

Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Roman Kisel <romank@linux.microsoft.com>
Link: https://lore.kernel.org/r/20240606025559.1631-1-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240606025559.1631-1-mhklinux@outlook.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:21:15 +01:00
Kees Cook
b619193f93 x86: Increase brk randomness entropy for 64-bit systems
[ Upstream commit 44c76825d6eefee9eb7ce06c38e1a6632ac7eb7d ]

In commit c1d171a00294 ("x86: randomize brk"), arch_randomize_brk() was
defined to use a 32MB range (13 bits of entropy), but was never increased
when moving to 64-bit. The default arch_randomize_brk() uses 32MB for
32-bit tasks, and 1GB (18 bits of entropy) for 64-bit tasks.

Update x86_64 to match the entropy used by arm64 and other 64-bit
architectures.

Reported-by: y0un9n132@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jiri Kosina <jkosina@suse.com>
Closes: https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzOUG5E4gV7ayCbu0MPJTZzWkw@mail.gmail.com/
Link: https://lore.kernel.org/r/20240217062545.1631668-1-keescook@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:46 +01:00
Andi Kleen
86b7095f72 x86/mtrr: Check if fixed MTRRs exist before saving them
commit 919f18f961c03d6694aa726c514184f2311a4614 upstream.

MTRRs have an obsolete fixed variant for fine grained caching control
of the 640K-1MB region that uses separate MSRs. This fixed variant has
a separate capability bit in the MTRR capability MSR.

So far all x86 CPUs which support MTRR have this separate bit set, so it
went unnoticed that mtrr_save_state() does not check the capability bit
before accessing the fixed MTRR MSRs.

Though on a CPU that does not support the fixed MTRR capability this
results in a #GP.  The #GP itself is harmless because the RDMSR fault is
handled gracefully, but results in a WARN_ON().

Add the missing capability check to prevent this.

Fixes: 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before booting an AP")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240808000244.946864-1-ak@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:20:30 +01:00
Peter Zijlstra
169950cfb4 x86/mm: Fix pti_clone_pgtable() alignment assumption
[ Upstream commit 41e71dbb0e0a0fe214545fe64af031303a08524c ]

Guenter reported dodgy crashes on an i386-nosmp build using GCC-11
that had the form of endless traps until entry stack exhaust and then
#DF from the stack guard.

It turned out that pti_clone_pgtable() had alignment assumptions on
the start address, notably it hard assumes start is PMD aligned. This
is true on x86_64, but very much not true on i386.

These assumptions can cause the end condition to malfunction, leading
to a 'short' clone. Guess what happens when the user mapping has a
short copy of the entry text?

Use the correct increment form for addr to avoid alignment
assumptions.

Fixes: 16a3fe634f6a ("x86/mm/pti: Clone kernel-image on PTE level for 32 bit")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20240731163105.GG33588@noisy.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:21 +01:00
Adrian Hunter
1202678b83 perf/x86/intel/pt: Fix a topa_entry base address calculation
commit ad97196379d0b8cb24ef3d5006978a6554e6467f upstream.

topa_entry->base is a bit-field. Bit-fields are not promoted to a 64-bit
type, even if the underlying type is 64-bit, and so, if necessary, must
be cast to a larger type when calculations are done.

Fix a topa_entry->base address calculation by adding a cast.

Without the cast, the address was limited to 36-bits i.e. 64GiB.

The address calculation is used on systems that do not support Multiple
Entry ToPA (only Broadwell), and affects physical addresses on or above
64GiB. Instead of writing to the correct address, the address comprising
the first 36 bits would be written to.

Intel PT snapshot and sampling modes are not affected.

Fixes: 52ca9ced3f70 ("perf/x86/intel/pt: Add Intel PT PMU driver")
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240624201101.60186-3-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:20:15 +01:00
Marco Cavenati
e17436440f perf/x86/intel/pt: Fix topa_entry base length
commit 5638bd722a44bbe97c1a7b3fae5b9efddb3e70ff upstream.

topa_entry->base needs to store a pfn.  It obviously needs to be
large enough to store the largest possible x86 pfn which is
MAXPHYADDR-PAGE_SIZE (52-12).  So it is 4 bits too small.

Increase the size of topa_entry->base from 36 bits to 40 bits.

Note, systems where physical addresses can be 256TiB or more are affected.

[ Adrian: Amend commit message as suggested by Dave Hansen ]

Fixes: 52ca9ced3f70 ("perf/x86/intel/pt: Add Intel PT PMU driver")
Signed-off-by: Marco Cavenati <cavenati.marco@gmail.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240624201101.60186-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:20:15 +01:00
Sean Christopherson
3cb4bafb59 KVM: VMX: Split out the non-virtualization part of vmx_interrupt_blocked()
commit 322a569c4b4188a0da2812f9e952780ce09b74ba upstream.

Move the non-VMX chunk of the "interrupt blocked" checks to a separate
helper so that KVM can reuse the code to detect if interrupts are blocked
for L2, e.g. to determine if a virtual interrupt _for L2_ is a valid wake
event.  If L1 disables HLT-exiting for L2, nested APICv is enabled, and L2
HLTs, then L2 virtual interrupts are valid wake events, but if and only if
interrupts are unblocked for L2.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240607172609.3205077-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:20:13 +01:00
Adrian Hunter
7947c2a479 perf/x86/intel/pt: Fix pt_topa_entry_for_page() address calculation
[ Upstream commit 3520b251dcae2b4a27b95cd6f745c54fd658bda5 ]

Currently, perf allocates an array of page pointers which is limited in
size by MAX_PAGE_ORDER. That in turn limits the maximum Intel PT buffer
size to 2GiB. Should that limitation be lifted, the Intel PT driver can
support larger sizes, except for one calculation in
pt_topa_entry_for_page(), which is limited to 32-bits.

Fix pt_topa_entry_for_page() address calculation by adding a cast.

Fixes: 39152ee51b77 ("perf/x86/intel/pt: Get rid of reverse lookup table for ToPA")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240624201101.60186-4-adrian.hunter@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:07 +01:00
Chen Ni
35dac179ce x86/xen: Convert comma to semicolon
[ Upstream commit 349d271416c61f82b853336509b1d0dc04c1fcbb ]

Replace a comma between expression statements by a semicolon.

Fixes: 8310b77b48c5 ("Xen/gnttab: handle p2m update errors on a per-slot basis")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20240702031010.1411875-1-nichen@iscas.ac.cn
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:06 +01:00
Ilpo Järvinen
1dd248abe6 x86/platform/iosf_mbi: Convert PCIBIOS_* return codes to errnos
[ Upstream commit 7821fa101eab529521aa4b724bf708149d70820c ]

iosf_mbi_pci_{read,write}_mdr() use pci_{read,write}_config_dword()
that return PCIBIOS_* codes but functions also return -ENODEV which are
not compatible error codes. As neither of the functions are related to
PCI read/write functions, they should return normal errnos.

Convert PCIBIOS_* returns code using pcibios_err_to_errno() into normal
errno before returning it.

Fixes: 46184415368a ("arch: x86: New MailBox support driver for Intel SOC's")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240527125538.13620-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:19:56 +01:00
Ilpo Järvinen
f7a37f0e61 x86/pci/xen: Fix PCIBIOS_* return code handling
[ Upstream commit e9d7b435dfaec58432f4106aaa632bf39f52ce9f ]

xen_pcifront_enable_irq() uses pci_read_config_byte() that returns
PCIBIOS_* codes. The error handling, however, assumes the codes are
normal errnos because it checks for < 0.

xen_pcifront_enable_irq() also returns the PCIBIOS_* code back to the
caller but the function is used as the (*pcibios_enable_irq) function
which should return normal errnos.

Convert the error check to plain non-zero check which works for
PCIBIOS_* return codes and convert the PCIBIOS_* return code using
pcibios_err_to_errno() into normal errno before returning it.

Fixes: 3f2a230caf21 ("xen: handled remapped IRQs when enabling a pcifront PCI device.")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20240527125538.13620-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:19:56 +01:00
Ilpo Järvinen
75196cdd48 x86/pci/intel_mid_pci: Fix PCIBIOS_* return code handling
[ Upstream commit 724852059e97c48557151b3aa4af424614819752 ]

intel_mid_pci_irq_enable() uses pci_read_config_byte() that returns
PCIBIOS_* codes. The error handling, however, assumes the codes are
normal errnos because it checks for < 0.

intel_mid_pci_irq_enable() also returns the PCIBIOS_* code back to the
caller but the function is used as the (*pcibios_enable_irq) function
which should return normal errnos.

Convert the error check to plain non-zero check which works for
PCIBIOS_* return codes and convert the PCIBIOS_* return code using
pcibios_err_to_errno() into normal errno before returning it.

Fixes: 5b395e2be6c4 ("x86/platform/intel-mid: Make IRQ allocation a bit more flexible")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240527125538.13620-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:19:56 +01:00
Ilpo Järvinen
cde52d3c67 x86/of: Return consistent error type from x86_of_pci_irq_enable()
[ Upstream commit ec0b4c4d45cf7cf9a6c9626a494a89cb1ae7c645 ]

x86_of_pci_irq_enable() returns PCIBIOS_* code received from
pci_read_config_byte() directly and also -EINVAL which are not
compatible error types. x86_of_pci_irq_enable() is used as
(*pcibios_enable_irq) function which should not return PCIBIOS_* codes.

Convert the PCIBIOS_* return code from pci_read_config_byte() into
normal errno using pcibios_err_to_errno().

Fixes: 96e0a0797eba ("x86: dtb: Add support for PCI devices backed by dtb nodes")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240527125538.13620-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:19:56 +01:00
Jim Mattson
bb2c67dee6 x86/retpoline: Move a NOENDBR annotation to the SRSO dummy return thunk
The linux-5.10-y backport of commit b377c66ae350 ("x86/retpoline: Add
NOENDBR annotation to the SRSO dummy return thunk") misplaced the new
NOENDBR annotation, repeating the annotation on __x86_return_thunk,
rather than adding the annotation to the !CONFIG_CPU_SRSO version of
srso_alias_untrain_ret, as intended.

Move the annotation to the right place.

Fixes: 0bdc64e9e716 ("x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk")
Reported-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:45 +01:00
Ard Biesheuvel
2aa6501b2f efi/x86: Free EFI memory map only when installing a new one.
[ Commit 75dde792d6f6c2d0af50278bd374bf0c512fe196 upstream ]

The logic in __efi_memmap_init() is shared between two different
execution flows:
- mapping the EFI memory map early or late into the kernel VA space, so
  that its entries can be accessed;
- the x86 specific cloning of the EFI memory map in order to insert new
  entries that are created as a result of making a memory reservation
  via a call to efi_mem_reserve().

In the former case, the underlying memory containing the kernel's view
of the EFI memory map (which may be heavily modified by the kernel
itself on x86) is not modified at all, and the only thing that changes
is the virtual mapping of this memory, which is different between early
and late boot.

In the latter case, an entirely new allocation is created that carries a
new, updated version of the kernel's view of the EFI memory map. When
installing this new version, the old version will no longer be
referenced, and if the memory was allocated by the kernel, it will leak
unless it gets freed.

The logic that implements this freeing currently lives on the code path
that is shared between these two use cases, but it should only apply to
the latter. So move it to the correct spot.

While at it, drop the dummy definition for non-x86 architectures, as
that is no longer needed.

Cc: <stable@vger.kernel.org>
Fixes: f0ef6523475f ("efi: Fix efi_memmap_alloc() leaks")
Tested-by: Ashish Kalra <Ashish.Kalra@amd.com>
Link: https://lore.kernel.org/all/36ad5079-4326-45ed-85f6-928ff76483d3@amd.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:35 +01:00
Ard Biesheuvel
0c7592211f efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architectures
[ Commit d85e3e34940788578eeffd94e8b7e1d28e7278e9 upstream ]

Currently, the EFI_PARAVIRT flag is only used by Xen dom0 boot on x86,
even though other architectures also support pseudo-EFI boot, where the
core kernel is invoked directly and provided with a set of data tables
that resemble the ones constructed by the EFI stub, which never actually
runs in that case.

Let's fix this inconsistency, and always set this flag when booting dom0
via the EFI boot path. Note that Xen on x86 does not provide the EFI
memory map in this case, whereas other architectures do, so move the
associated EFI_PARAVIRT check into the x86 platform code.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:35 +01:00
Ard Biesheuvel
67c6fa1332 efi: memmap: Move manipulation routines into x86 arch tree
[ Commit fdc6d38d64a20c542b1867ebeb8dd03b98829336 upstream ]

The EFI memory map is a description of the memory layout as provided by
the firmware, and only x86 manipulates it in various different ways for
its own memory bookkeeping. So let's move the memmap routines that are
only used by x86 into the x86 arch tree.

[ardb: minor tweaks for linux-5.10.y backport]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:35 +01:00
Arnd Bergmann
e0221b0a4a syscalls: fix compat_sys_io_pgetevents_time64 usage
commit d3882564a77c21eb746ba5364f3fa89b88de3d61 upstream.

Using sys_io_pgetevents() as the entry point for compat mode tasks
works almost correctly, but misses the sign extension for the min_nr
and nr arguments.

This was addressed on parisc by switching to
compat_sys_io_pgetevents_time64() in commit 6431e92fc827 ("parisc:
io_pgetevents_time64() needs compat syscall in 32-bit compat mode"),
as well as by using more sophisticated system call wrappers on x86 and
s390. However, arm64, mips, powerpc, sparc and riscv still have the
same bug.

Change all of them over to use compat_sys_io_pgetevents_time64()
like parisc already does. This was clearly the intention when the
function was originally added, but it got hooked up incorrectly in
the tables.

Cc: stable@vger.kernel.org
Fixes: 48166e6ea47d ("y2038: add 64-bit time_t syscalls to all 32-bit architectures")
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:34 +01:00
Linus Torvalds
9561ddb626 x86: stop playing stack games in profile_pc()
[ Upstream commit 093d9603b60093a9aaae942db56107f6432a5dca ]

The 'profile_pc()' function is used for timer-based profiling, which
isn't really all that relevant any more to begin with, but it also ends
up making assumptions based on the stack layout that aren't necessarily
valid.

Basically, the code tries to account the time spent in spinlocks to the
caller rather than the spinlock, and while I support that as a concept,
it's not worth the code complexity or the KASAN warnings when no serious
profiling is done using timers anyway these days.

And the code really does depend on stack layout that is only true in the
simplest of cases.  We've lost the comment at some point (I think when
the 32-bit and 64-bit code was unified), but it used to say:

	Assume the lock function has either no stack frame or a copy
	of eflags from PUSHF.

which explains why it just blindly loads a word or two straight off the
stack pointer and then takes a minimal look at the values to just check
if they might be eflags or the return pc:

	Eflags always has bits 22 and up cleared unlike kernel addresses

but that basic stack layout assumption assumes that there isn't any lock
debugging etc going on that would complicate the code and cause a stack
frame.

It causes KASAN unhappiness reported for years by syzkaller [1] and
others [2].

With no real practical reason for this any more, just remove the code.

Just for historical interest, here's some background commits relating to
this code from 2006:

  0cb91a229364 ("i386: Account spinlocks to the caller during profiling for !FP kernels")
  31679f38d886 ("Simplify profile_pc on x86-64")

and a code unification from 2009:

  ef4512882dbe ("x86: time_32/64.c unify profile_pc")

but the basics of this thing actually goes back to before the git tree.

Link: https://syzkaller.appspot.com/bug?extid=84fe685c02cd112a2ac3 [1]
Link: https://lore.kernel.org/all/CAK55_s7Xyq=nh97=K=G1sxueOFrJDAvPOJAL4TPTCAYvmxO9_A@mail.gmail.com/ [2]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:33 +01:00
Yazen Ghannam
80852dba1a x86/amd_nb: Check for invalid SMN reads
[ Upstream commit c625dabbf1c4a8e77e4734014f2fde7aa9071a1f ]

AMD Zen-based systems use a System Management Network (SMN) that
provides access to implementation-specific registers.

SMN accesses are done indirectly through an index/data pair in PCI
config space. The PCI config access may fail and return an error code.
This would prevent the "read" value from being updated.

However, the PCI config access may succeed, but the return value may be
invalid. This is in similar fashion to PCI bad reads, i.e. return all
bits set.

Most systems will return 0 for SMN addresses that are not accessible.
This is in line with AMD convention that unavailable registers are
Read-as-Zero/Writes-Ignored.

However, some systems will return a "PCI Error Response" instead. This
value, along with an error code of 0 from the PCI config access, will
confuse callers of the amd_smn_read() function.

Check for this condition, clear the return value, and set a proper error
code.

Fixes: ddfe43cdc0da ("x86/amd_nb: Add SMN and Indirect Data Fabric access for AMD Fam17h")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230403164244.471141-1-yazen.ghannam@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:30 +01:00
Tony Luck
329eef5594 x86/cpu: Fix x86_match_cpu() to match just X86_VENDOR_INTEL
[ Upstream commit 93022482b2948a9a7e9b5a2bb685f2e1cb4c3348 ]

Code in v6.9 arch/x86/kernel/smpboot.c was changed by commit

  4db64279bc2b ("x86/cpu: Switch to new Intel CPU model defines") from:

  static const struct x86_cpu_id intel_cod_cpu[] = {
          X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, 0),       /* COD */
          X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, 0),     /* COD */
          X86_MATCH_INTEL_FAM6_MODEL(ANY, 1),             /* SNC */	<--- 443
          {}
  };

  static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
  {
          const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);

to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
           X86_MATCH_VFM(INTEL_HASWELL_X,   0),    /* COD */
           X86_MATCH_VFM(INTEL_BROADWELL_X, 0),    /* COD */
           X86_MATCH_VFM(INTEL_ANY,         1),    /* SNC */
           {}
   };

  static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
  {
          const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);

On an Intel CPU with SNC enabled this code previously matched the rule on line
443 to avoid printing messages about insane cache configuration.  The new code
did not match any rules.

Expanding the macros for the intel_cod_cpu[] array shows that the old is
equivalent to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
  [0] = { .vendor = 0, .family = 6, .model = 0x3F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [1] = { .vendor = 0, .family = 6, .model = 0x4F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [2] = { .vendor = 0, .family = 6, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 1 },
  [3] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 0 }
  }

while the new code expands to:

  static const struct x86_cpu_id intel_cod_cpu[] = {
  [0] = { .vendor = 0, .family = 6, .model = 0x3F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [1] = { .vendor = 0, .family = 6, .model = 0x4F, .steppings = 0, .feature = 0, .driver_data = 0 },
  [2] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 1 },
  [3] = { .vendor = 0, .family = 0, .model = 0x00, .steppings = 0, .feature = 0, .driver_data = 0 }
  }

Looking at the code for x86_match_cpu():

  const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
  {
           const struct x86_cpu_id *m;
           struct cpuinfo_x86 *c = &boot_cpu_data;

           for (m = match;
                m->vendor | m->family | m->model | m->steppings | m->feature;
                m++) {
       		...
           }
           return NULL;

it is clear that there was no match because the ANY entry in the table (array
index 2) is now the loop termination condition (all of vendor, family, model,
steppings, and feature are zero).

So this code was working before because the "ANY" check was looking for any
Intel CPU in family 6. But fails now because the family is a wild card. So the
root cause is that x86_match_cpu() has never been able to match on a rule with
just X86_VENDOR_INTEL and all other fields set to wildcards.

Add a new flags field to struct x86_cpu_id that has a bit set to indicate that
this entry in the array is valid. Update X86_MATCH*() macros to set that bit.
Change the end-marker check in x86_match_cpu() to just check the flags field
for this bit.

Backporter notes: The commit in Fixes is really the one that is broken:
you can't have m->vendor as part of the loop termination conditional in
x86_match_cpu() because it can happen - as it has happened above
- that that whole conditional is 0 albeit vendor == 0 is a valid case
- X86_VENDOR_INTEL is 0.

However, the only case where the above happens is the SNC check added by
4db64279bc2b1 so you only need this fix if you have backported that
other commit

  4db64279bc2b ("x86/cpu: Switch to new Intel CPU model defines")

Fixes: 644e9cbbe3fc ("Add driver auto probing for x86 features v4")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable+noautosel@kernel.org> # see above
Link: https://lore.kernel.org/r/20240517144312.GBZkdtAOuJZCvxhFbJ@fat_crate.local
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:29 +01:00
Tony Luck
765a859979 x86/cpu/vfm: Add new macros to work with (vendor/family/model) values
[ Upstream commit e6dfdc2e89a0adedf455814c91b977d6a584cc88 ]

To avoid adding a slew of new macros for each new Intel CPU family
switch over from providing CPU model number #defines to a new
scheme that encodes vendor, family, and model in a single number.

  [ bp: s/casted/cast/g ]

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240416211941.9369-3-tony.luck@intel.com
Stable-dep-of: 93022482b294 ("x86/cpu: Fix x86_match_cpu() to match just X86_VENDOR_INTEL")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:29 +01:00