Commit 8a68d64bb1 upstream.
These old CPUs are not tested against VMSCAPE, but are likely vulnerable.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit b7cc988723 upstream.
Cross-thread attacks are generally harder as they require the victim to be
co-located on a core. However, with VMSCAPE the adversary targets belong to
the same guest execution, that are more likely to get co-located. In
particular, a thread that is currently executing userspace hypervisor
(after the IBPB) may still be targeted by a guest execution from a sibling
thread.
Issue a warning about the potential risk, except when:
- SMT is disabled
- STIBP is enabled system-wide
- Intel eIBRS is enabled (which implies STIBP protection)
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 6449f5baf9 upstream.
cpu_bugs_smt_update() uses global variables from different mitigations. For
SMT updates it can't currently use vmscape_mitigation that is defined after
it.
Since cpu_bugs_smt_update() depends on many other mitigations, move it
after all mitigations are defined. With that, it can use vmscape_mitigation
in a moment.
No functional change.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 2f8f173413 upstream.
VMSCAPE is a vulnerability that exploits insufficient branch predictor
isolation between a guest and a userspace hypervisor (like QEMU). Existing
mitigations already protect kernel/KVM from a malicious guest. Userspace
can additionally be protected by flushing the branch predictors after a
VMexit.
Since it is the userspace that consumes the poisoned branch predictors,
conditionally issue an IBPB after a VMexit and before returning to
userspace. Workloads that frequently switch between hypervisor and
userspace will incur the most overhead from the new IBPB.
This new IBPB is not integrated with the existing IBPB sites. For
instance, a task can use the existing speculation control prctl() to
get an IBPB at context switch time. With this implementation, the
IBPB is doubled up: one at context switch and another before running
userspace.
The intent is to integrate and optimize these cases post-embargo.
[ dhansen: elaborate on suboptimal IBPB solution ]
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>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit a508cec6e5 upstream.
The VMSCAPE vulnerability may allow a guest to cause Branch Target
Injection (BTI) in userspace hypervisors.
Kernels (both host and guest) have existing defenses against direct BTI
attacks from guests. There are also inter-process BTI mitigations which
prevent processes from attacking each other. However, the threat in this
case is to a userspace hypervisor within the same process as the attacker.
Userspace hypervisors have access to their own sensitive data like disk
encryption keys and also typically have access to all guest data. This
means guest userspace may use the hypervisor as a confused deputy to attack
sensitive guest kernel data. There are no existing mitigations for these
attacks.
Introduce X86_BUG_VMSCAPE for this vulnerability and set it on affected
Intel and AMD CPUs.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c53cf8ce3b ]
Add missing microSD slot vqmmc-supply property, otherwise the kernel
might shut down LDO5 regulator and that would power off the microSD
card slot, possibly while it is in use. Add the property to make sure
the kernel is aware of the LDO5 regulator which supplies the microSD
slot and keeps the LDO5 enabled.
Fixes: 8d6712695b ("arm64: dts: imx8mp: Add support for DH electronics i.MX8M Plus DHCOM and PDK2")
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d1f9c49761 ]
As described in the pinebookpro_v2.1_mainboard_schematic.pdf page 10,
he SPI Flash's VCC connector is connected to VCC_3V0 power source.
This fixes the following warning:
spi-nor spi1.0: supply vcc not found, using dummy regulator
Fixes: 5a65505a69 ("arm64: dts: rockchip: Add initial support for Pinebook Pro")
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Dragan Simic <dsimic@manjaro.org>
Link: https://lore.kernel.org/r/20250730102129.224468-1-pbrobinson@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 88688a2c8a ]
When compiling for pseries or powernv defconfig with "make C=1",
these warning were reported bu sparse tool in powerpc/kernel/kvm.c
arch/powerpc/kernel/kvm.c:635:9: warning: switch with no cases
arch/powerpc/kernel/kvm.c:646:9: warning: switch with no cases
Currently #ifdef were added after the switch case which are specific
for BOOKE and PPC_BOOK3S_32. These are not enabled in pseries/powernv
defconfig. Fix it by moving the #ifdef before switch(){}
Fixes: cbe487fac7 ("KVM: PPC: Add mtsrin PV code")
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250518044107.39928-1-maddy@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8c431ea8f3 ]
Bindig requires a node name matching ‘^ethernet@[0-9a-f]+$’. This patch
changes the clock name from “etop” to “ethernet”.
This fixes the following warning:
arch/mips/boot/dts/lantiq/danube_easy50712.dtb: etop@e180000 (lantiq,etop-xway): $nodename:0: 'etop@e180000' does not match '^ethernet@[0-9a-f]+$'
from schema $id: http://devicetree.org/schemas/net/lantiq,etop-xway.yaml#
Fixes: dac0bad937 ("dt-bindings: net: lantiq,etop-xway: Document Lantiq Xway ETOP bindings")
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7b28232921 ]
The upstream dts lacks the lantiq,{rx/tx}-burst-length property. Other
issues were also fixed:
arch/mips/boot/dts/lantiq/danube_easy50712.dtb: etop@e180000 (lantiq,etop-xway): 'interrupt-names' is a required property
from schema $id: http://devicetree.org/schemas/net/lantiq,etop-xway.yaml#
arch/mips/boot/dts/lantiq/danube_easy50712.dtb: etop@e180000 (lantiq,etop-xway): 'lantiq,tx-burst-length' is a required property
from schema $id: http://devicetree.org/schemas/net/lantiq,etop-xway.yaml#
arch/mips/boot/dts/lantiq/danube_easy50712.dtb: etop@e180000 (lantiq,etop-xway): 'lantiq,rx-burst-length' is a required property
from schema $id: http://devicetree.org/schemas/net/lantiq,etop-xway.yaml#
Fixes: 14d4e308e0 ("net: lantiq: configure the burst length in ethernet drivers")
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3868f91044 ]
When kernel lockdown is active, debugfs_locked_down() blocks access to
hypfs files that register ioctl callbacks, even if the ioctl interface
is not required for a function. This unnecessarily breaks userspace
tools that only rely on read operations.
Resolve this by registering a minimal set of file operations during
lockdown, avoiding ioctl registration and preserving access for affected
tooling.
Note that this change restores hypfs functionality when lockdown is
active from early boot (e.g. via lockdown=integrity kernel parameter),
but does not apply to scenarios where lockdown is enabled dynamically
while Linux is running.
Tested-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Fixes: 5496197f9b ("debugfs: Restrict debugfs when the kernel is locked down")
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fec7bdfe7f ]
Currently, hypfs registers ioctl callbacks for all debugfs files,
despite only one file requiring them. This leads to unintended exposure
of unused interfaces to user space and can trigger side effects such as
restricted access when kernel lockdown is enabled.
Restrict ioctl registration to only those files that implement ioctl
functionality to avoid interface clutter and unnecessary access
restrictions.
Tested-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Fixes: 5496197f9b ("debugfs: Restrict debugfs when the kernel is locked down")
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit d8df126349 upstream.
Since
923f3a2b48 ("x86/resctrl: Query LLC monitoring properties once during boot")
resctrl_cpu_detect() has been moved from common CPU initialization code to
the vendor-specific BSP init helper, while Hygon didn't put that call in their
code.
This triggers a division by zero fault during early booting stage on our
machines with X86_FEATURE_CQM* supported, where get_rdt_mon_resources() tries
to calculate mon_l3_config with uninitialized boot_cpu_data.x86_cache_occ_scale.
Add the missing resctrl_cpu_detect() in the Hygon BSP init helper.
[ bp: Massage commit message. ]
Fixes: 923f3a2b48 ("x86/resctrl: Query LLC monitoring properties once during boot")
Signed-off-by: Tianxiang Peng <txpeng@tencent.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Hui Li <caelli@tencent.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/20250623093153.3016937-1-txpeng@tencent.com
Signed-off-by: Tianxiang Peng <txpeng@tencent.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8ea815399c ]
__ADDRESSABLE_ASM_STR() is where the necessary stringification happens.
As long as "sym" doesn't contain any odd characters, no quoting is
required for its use with .quad / .long. In fact the quotation gets in
the way with gas 2.25; it's only from 2.26 onwards that quoted symbols
are half-way properly supported.
However, assembly being different from C anyway, drop
__ADDRESSABLE_ASM_STR() and its helper macro altogether. A simple
.global directive will suffice to get the symbol "declared", i.e. into
the symbol table. While there also stop open-coding STATIC_CALL_TRAMP()
and STATIC_CALL_KEY().
Fixes: 0ef8047b73 ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <609d2c74-de13-4fae-ab1a-1ec44afb948d@suse.com>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Upstream commit fbc7e61195 ("KVM: arm64: Unconditionally save+flush
host FPSIMD/SVE/SME state") relies on interrupts being disabled during
fpsimd_save_and_flush_cpu_state() so that a softirq cannot be taken
while the host floating point context is being saved and potentially try
to use kernel-mode NEON.
Unfortunately, stable kernels without 9b19700e62 ("arm64: fpsimd: Drop
unneeded 'busy' flag") leave interrupts enabled in
fpsimd_save_and_flush_cpu_state() and so the BUG_ON(!may_use_simd()) in
kernel_neon_begin() has been observed to trigger in real-world usage:
| kernel BUG at arch/arm64/kernel/fpsimd.c:1904!
| Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
|
| Call trace:
| kernel_neon_begin+0xdc/0x12c
| ...
| crypto_aead_decrypt+0x5c/0x6c
| seqiv_aead_decrypt+0x88/0x9c
| crypto_aead_decrypt+0x5c/0x6c
| esp_input+0x280/0x364
| xfrm_input+0x6ac/0x16f8
| ...
| net_rx_action+0x13c/0x31c
| handle_softirqs+0x124/0x3d0
| __do_softirq+0x14/0x20
| ____do_softirq+0x10/0x20
| call_on_irq_stack+0x3c/0x74
| do_softirq_own_stack+0x1c/0x2c
| __irq_exit_rcu+0x54/0xb4
| irq_exit_rcu+0x10/0x1c
| el1_interrupt+0x38/0x58
| el1h_64_irq_handler+0x18/0x24
| el1h_64_irq+0x68/0x6c
| fpsimd_save+0xe4/0x130
| kvm_arch_vcpu_load_fp+0x2c/0x58
| kvm_arch_vcpu_load+0x88/0x26c
| kvm_sched_in+0x2c/0x3c
Given that 9b19700e62 ("arm64: fpsimd: Drop unneeded 'busy' flag") is
not a fix in its own right, has non-trivial dependencies and is a
reasonably invasive change to the in-kernel use of fpsimd, opt instead
for a simple fix to use the softirq-safe {get,put}_cpu_fpsimd_context()
helpers in fpsimd_save_and_flush_cpu_state().
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Lee Jones <lee@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: <stable@vger.kernel.org> # 5.15.y, 6.1.y and 6.6.y
Fixes: 806d5c1e1d ("KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state") # 6.6.y
Fixes: 04c50cc23a ("KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state") # 6.1.y
Fixes: 5289ac43b6 ("KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state") # 5.15.y
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a0ee1d5faf ]
Ensure the shadow VMCS cache is evicted during an emergency reboot to
prevent potential memory corruption if the cache is evicted after reboot.
This issue was identified through code inspection, as __loaded_vmcs_clear()
flushes both the normal VMCS and the shadow VMCS.
Avoid checking the "launched" state during an emergency reboot, unlike the
behavior in __loaded_vmcs_clear(). This is important because reboot NMIs
can interfere with operations like copy_shadow_to_vmcs12(), where shadow
VMCSes are loaded directly using VMPTRLD. In such cases, if NMIs occur
right after the VMCS load, the shadow VMCSes will be active but the
"launched" state may not be set.
Fixes: 16f5b9034b ("KVM: nVMX: Copy processor-specific shadow-vmcs to VMCS12")
Cc: stable@vger.kernel.org
Signed-off-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20250324140849.2099723-1-chao.gao@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 119b5cb4ff ]
Use KVM VMX's reboot/crash callback to do VMXOFF in an emergency instead
of manually and blindly doing VMXOFF. There's no need to attempt VMXOFF
if a hypervisor, i.e. KVM, isn't loaded/active, i.e. if the CPU can't
possibly be post-VMXON.
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20230721201859.2307736-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Stable-dep-of: a0ee1d5faf ("KVM: VMX: Flush shadow VMCS on emergency reboot")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5e408396c6 ]
Provide dedicated helpers to (un)register virt hooks used during an
emergency crash/reboot, and WARN if there is an attempt to overwrite
the registered callback, or an attempt to do an unpaired unregister.
Opportunsitically use rcu_assign_pointer() instead of RCU_INIT_POINTER(),
mainly so that the set/unset paths are more symmetrical, but also because
any performance gains from using RCU_INIT_POINTER() are meaningless for
this code.
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20230721201859.2307736-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Stable-dep-of: a0ee1d5faf ("KVM: VMX: Flush shadow VMCS on emergency reboot")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f1fb088d9c upstream.
Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure
irqfd->producer isn't modified while kvm_irq_routing_update() is running.
The only lock held when a producer is added/removed is irqbypass's mutex.
Fixes: 8727688006 ("KVM: x86: select IRQ_BYPASS_MANAGER")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250404193923.1413163-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[sean: account for lack of kvm_x86_call()]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e8cde32f11 upstream.
Enable ECBHB bits in ID_AA64MMFR1 register as per ARM DDI 0487K.a
specification.
When guest OS read ID_AA64MMFR1_EL1, kvm emulate this reg using
ftr_id_aa64mmfr1 and always return ID_AA64MMFR1_EL1.ECBHB=0 to guest.
It results in guest syscall jump to tramp ventry, which is not needed
in implementation with ID_AA64MMFR1_EL1.ECBHB=1.
Let's make the guest syscall process the same as the host.
Signed-off-by: Nianyao Tang <tangnianyao@huawei.com>
Link: https://lore.kernel.org/r/20240611122049.2758600-1-tangnianyao@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Patrick Roy <roypat@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 59305202c6 ]
Memory hot remove unmaps and tears down various kernel page table regions
as required. The ptdump code can race with concurrent modifications of
the kernel page tables. When leaf entries are modified concurrently, the
dump code may log stale or inconsistent information for a VA range, but
this is otherwise not harmful.
But when intermediate levels of kernel page table are freed, the dump code
will continue to use memory that has been freed and potentially
reallocated for another purpose. In such cases, the ptdump code may
dereference bogus addresses, leading to a number of potential problems.
To avoid the above mentioned race condition, platforms such as arm64,
riscv and s390 take memory hotplug lock, while dumping kernel page table
via the sysfs interface /sys/kernel/debug/kernel_page_tables.
Similar race condition exists while checking for pages that might have
been marked W+X via /sys/kernel/debug/kernel_page_tables/check_wx_pages
which in turn calls ptdump_check_wx(). Instead of solving this race
condition again, let's just move the memory hotplug lock inside generic
ptdump_check_wx() which will benefit both the scenarios.
Drop get_online_mems() and put_online_mems() combination from all existing
platform ptdump code paths.
Link: https://lkml.kernel.org/r/20250620052427.2092093-1-anshuman.khandual@arm.com
Fixes: bbd6ec605c ("arm64/mm: Enable memory hot remove")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> [s390]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d42e6c20de ]
`cpu_switch_to()` and `call_on_irq_stack()` manipulate SP to change
to different stacks along with the Shadow Call Stack if it is enabled.
Those two stack changes cannot be done atomically and both functions
can be interrupted by SErrors or Debug Exceptions which, though unlikely,
is very much broken : if interrupted, we can end up with mismatched stacks
and Shadow Call Stack leading to clobbered stacks.
In `cpu_switch_to()`, it can happen when SP_EL0 points to the new task,
but x18 stills points to the old task's SCS. When the interrupt handler
tries to save the task's SCS pointer, it will save the old task
SCS pointer (x18) into the new task struct (pointed to by SP_EL0),
clobbering it.
In `call_on_irq_stack()`, it can happen when switching from the task stack
to the IRQ stack and when switching back. In both cases, we can be
interrupted when the SCS pointer points to the IRQ SCS, but SP points to
the task stack. The nested interrupt handler pushes its return addresses
on the IRQ SCS. It then detects that SP points to the task stack,
calls `call_on_irq_stack()` and clobbers the task SCS pointer with
the IRQ SCS pointer, which it will also use !
This leads to tasks returning to addresses on the wrong SCS,
or even on the IRQ SCS, triggering kernel panics via CONFIG_VMAP_STACK
or FPAC if enabled.
This is possible on a default config, but unlikely.
However, when enabling CONFIG_ARM64_PSEUDO_NMI, DAIF is unmasked and
instead the GIC is responsible for filtering what interrupts the CPU
should receive based on priority.
Given the goal of emulating NMIs, pseudo-NMIs can be received by the CPU
even in `cpu_switch_to()` and `call_on_irq_stack()`, possibly *very*
frequently depending on the system configuration and workload, leading
to unpredictable kernel panics.
Completely mask DAIF in `cpu_switch_to()` and restore it when returning.
Do the same in `call_on_irq_stack()`, but restore and mask around
the branch.
Mask DAIF even if CONFIG_SHADOW_CALL_STACK is not enabled for consistency
of behaviour between all configurations.
Introduce and use an assembly macro for saving and masking DAIF,
as the existing one saves but only masks IF.
Cc: <stable@vger.kernel.org>
Signed-off-by: Ada Couprie Diaz <ada.coupriediaz@arm.com>
Reported-by: Cristian Prundeanu <cpru@amazon.com>
Fixes: 59b37fe52f ("arm64: Stash shadow stack pointer in the task struct on interrupt")
Tested-by: Cristian Prundeanu <cpru@amazon.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20250718142814.133329-1-ada.coupriediaz@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
[ removed duplicate save_and_disable_daif macro ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 87c4e1459e ]
After commit d5c8d6e0fa ("kbuild: Update assembler calls to use proper
flags and language target"), which updated as-instr to use the
'assembler-with-cpp' language option, the Kbuild version of as-instr
always fails internally for arch/arm with
<command-line>: fatal error: asm/unified.h: No such file or directory
compilation terminated.
because '-include' flags are now taken into account by the compiler
driver and as-instr does not have '$(LINUXINCLUDE)', so unified.h is not
found.
This went unnoticed at the time of the Kbuild change because the last
use of as-instr in Kbuild that arch/arm could reach was removed in 5.7
by commit 541ad0150c ("arm: Remove 32bit KVM host support") but a
stable backport of the Kbuild change to before that point exposed this
potential issue if one were to be reintroduced.
Follow the general pattern of '-include' paths throughout the tree and
make unified.h absolute using '$(srctree)' to ensure KBUILD_AFLAGS can
be used independently.
Closes: https://lore.kernel.org/CACo-S-1qbCX4WAVFA63dWfHtrRHZBTyyr2js8Lx=Az03XHTTHg@mail.gmail.com/
Cc: stable@vger.kernel.org
Fixes: d5c8d6e0fa ("kbuild: Update assembler calls to use proper flags and language target")
Reported-by: KernelCI bot <bot@kernelci.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
[ adapted to missing -Wa ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d66e1e90b1 ]
Ensure that sysfs init doesn't fail for new/unrecognized bank types or if
a bank has additional blocks available.
Most MCA banks have a single thresholding block, so the block takes the same
name as the bank.
Unified Memory Controllers (UMCs) are a special case where there are two
blocks and each has a unique name.
However, the microarchitecture allows for five blocks. Any new MCA bank types
with more than one block will be missing names for the extra blocks. The MCE
sysfs will fail to initialize in this case.
Fixes: 87a6d4091b ("x86/mce/AMD: Update sysfs bank names for SMCA systems")
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/20250624-wip-mca-updates-v4-3-236dd74f645f@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b0823d5fba ]
The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:
Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
CPU: 23 UID: 0 PID: 0 Comm: swapper/23
Tainted: [W]=WARN
Hardware name: Dell Inc. Precision 9660/0VJ762
RIP: 0010:native_read_pmc+0x7/0x40
Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
RSP: 000:fffb03100273de8 EFLAGS: 00010046
....
Call Trace:
<TASK>
icl_update_topdown_event+0x165/0x190
? ktime_get+0x38/0xd0
intel_pmu_read_event+0xf9/0x210
__perf_event_read+0xf9/0x210
CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.
It's a regression of commit:
f9bdf1f953 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.
Fix it.
Fixes: f9bdf1f953 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
[ omitted PEBS check ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cb22f247f3 upstream.
The following testcase exposed a problem with our read access checks
in get_user() and raw_copy_from_user():
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/mman.h>
#include <sys/types.h>
int main(int argc, char **argv)
{
unsigned long page_size = sysconf(_SC_PAGESIZE);
char *p = malloc(3 * page_size);
char *p_aligned;
/* initialize memory region. If not initialized, write syscall below will correctly return EFAULT. */
if (1)
memset(p, 'X', 3 * page_size);
p_aligned = (char *) ((((uintptr_t) p) + (2*page_size - 1)) & ~(page_size - 1));
/* Drop PROT_READ protection. Kernel and userspace should fault when accessing that memory region */
mprotect(p_aligned, page_size, PROT_NONE);
/* the following write() should return EFAULT, since PROT_READ was dropped by previous mprotect() */
int ret = write(2, p_aligned, 1);
if (!ret || errno != EFAULT)
printf("\n FAILURE: write() did not returned expected EFAULT value\n");
return 0;
}
Because of the way _PAGE_READ is handled, kernel code never generates
a read access fault when it access a page as the kernel privilege level
is always less than PL1 in the PTE.
This patch reworks the comments in the make_insert_tlb macro to try
to make this clearer.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f6334f4ae9 upstream.
We use load and stbys,e instructions to trigger memory reference
interruptions without writing to memory. Because of the way read
access support is implemented, read access interruptions are only
triggered at privilege levels 2 and 3. The kernel and gateway
page execute at privilege level 0, so this code never triggers
a read access interruption. Thus, it is currently possible for
user code to execute a LWS compare and swap operation at an
address that is read protected at privilege level 3 (PRIV_USER).
Fix this by probing read access rights at privilege level 3 and
branching to lws_fault if access isn't allowed.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 89f686a0fb upstream.
Because of the way read access support is implemented, read access
interruptions are only triggered at privilege levels 2 and 3. The
kernel executes at privilege level 0, so __get_user() never triggers
a read access interruption (code 26). Thus, it is currently possible
for user code to access a read protected address via a system call.
Fix this by probing read access rights at privilege level 3 (PRIV_USER)
and setting __gu_err to -EFAULT (-14) if access isn't allowed.
Note the cmpiclr instruction does a 32-bit compare because COND macro
doesn't work inside asm.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 305ab0a748 upstream.
For building a 64-bit kernel, both 32-bit and 64-bit VDSO binaries
are built, so both 32-bit and 64-bit compilers (and tools) should be
in the PATH environment variable.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 91428ca932 upstream.
Because of the way the _PAGE_READ is handled in the parisc PTE, an
access interruption is not generated when the kernel reads from a
region where the _PAGE_READ is zero. The current code was written
assuming read access faults would also occur in the kernel.
This change adds user access checks to raw_copy_from_user(). The
prober_user() define checks whether user code has read access to
a virtual address. Note that page faults are not handled in the
exception support for the probe instruction. For this reason, we
precede the probe by a ldb access check.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 22375adaa0 upstream.
The MIPS32r2 ChaCha code has never been buildable with the clang
assembler. First, clang doesn't support the 'rotl' pseudo-instruction:
error: unknown instruction, did you mean: rol, rotr?
Second, clang requires that both operands of the 'wsbh' instruction be
explicitly given:
error: too few operands for instruction
To fix this, align the code with the real instruction set by (1) using
the real instruction 'rotr' instead of the nonstandard pseudo-
instruction 'rotl', and (2) explicitly giving both operands to 'wsbh'.
To make removing the use of 'rotl' a bit easier, also remove the
unnecessary special-casing for big endian CPUs at
.Lchacha_mips_xor_bytes. The tail handling is actually
endian-independent since it processes one byte at a time. On big endian
CPUs the old code byte-swapped SAVED_X, then iterated through it in
reverse order. But the byteswap and reverse iteration canceled out.
Tested with chacha20poly1305-selftest in QEMU using "-M malta" with both
little endian and big endian mips32r2 kernels.
Fixes: 49aa7c00ed ("crypto: mips/chacha - import 32r2 ChaCha code from Zinc")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202505080409.EujEBwA0-lkp@intel.com/
Link: https://lore.kernel.org/r/20250619225535.679301-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 210a1ce8ed upstream.
Move the cursor position rightward after rendering the character,
not before. This avoids complications that arise when the recursive
console_putc call has to wrap the line and/or scroll the display.
This also fixes the linewrap bug that crops off the rightmost column.
When the cursor is at the bottom of the display, a linefeed will not
move the cursor position further downward. Instead, the display scrolls
upward. Avoid the repeated add/subtract sequence by way of a single
subtraction at the initialization of console_struct_num_rows.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Tested-by: Stan Johnson <userm57@yahoo.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/9d4e8c68a456d5f2bc254ac6f87a472d066ebd5e.1743115195.git.fthain@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9c9a7ff988 ]
request_mem_region() will return NULL instead of error code
when the memory request fails. Therefore, we should check if
the return value is non-zero instead of less than zero. In
this way, this patch also fixes the build warnings:
arch/mips/lantiq/falcon/sysctrl.c:214:50: error: ordered comparison of pointer with integer zero [-Werror=extra]
214 | res_status.name) < 0) ||
| ^
arch/mips/lantiq/falcon/sysctrl.c:216:47: error: ordered comparison of pointer with integer zero [-Werror=extra]
216 | res_ebu.name) < 0) ||
| ^
arch/mips/lantiq/falcon/sysctrl.c:219:50: error: ordered comparison of pointer with integer zero [-Werror=extra]
219 | res_sys[0].name) < 0) ||
| ^
arch/mips/lantiq/falcon/sysctrl.c:222:50: error: ordered comparison of pointer with integer zero [-Werror=extra]
222 | res_sys[1].name) < 0) ||
| ^
arch/mips/lantiq/falcon/sysctrl.c:225:50: error: ordered comparison of pointer with integer zero [-Werror=extra]
225 | res_sys[2].name) < 0))
|
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e9f4a6b342 ]
Not all tasks have an ABI associated or vDSO mapped,
for example kthreads never do.
If such a task ever ends up calling stack_top(), it will derefence the
NULL ABI pointer and crash.
This can for example happen when using kunit:
mips_stack_top+0x28/0xc0
arch_pick_mmap_layout+0x190/0x220
kunit_vm_mmap_init+0xf8/0x138
__kunit_add_resource+0x40/0xa8
kunit_vm_mmap+0x88/0xd8
usercopy_test_init+0xb8/0x240
kunit_try_run_case+0x5c/0x1a8
kunit_generic_run_threadfn_adapter+0x28/0x50
kthread+0x118/0x240
ret_from_kernel_thread+0x14/0x1c
Only dereference the ABI point if it is set.
The GIC page is also included as it is specific to the vDSO.
Also move the randomization adjustment into the same conditional.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 844615dd0f ]
These functions are exported but their prototypes are not defined.
This patch adds the missing function prototypes to fix the following
compilation warnings:
arch/mips/kernel/vpe-mt.c:180:7: error: no previous prototype for 'vpe_alloc' [-Werror=missing-prototypes]
180 | void *vpe_alloc(void)
| ^~~~~~~~~
arch/mips/kernel/vpe-mt.c:198:5: error: no previous prototype for 'vpe_start' [-Werror=missing-prototypes]
198 | int vpe_start(void *vpe, unsigned long start)
| ^~~~~~~~~
arch/mips/kernel/vpe-mt.c:208:5: error: no previous prototype for 'vpe_stop' [-Werror=missing-prototypes]
208 | int vpe_stop(void *vpe)
| ^~~~~~~~
arch/mips/kernel/vpe-mt.c:229:5: error: no previous prototype for 'vpe_free' [-Werror=missing-prototypes]
229 | int vpe_free(void *vpe)
| ^~~~~~~~
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cf183c1730 ]
The DMA map functions can fail and should be tested for errors.
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250620075602.12575-1-fourier.thomas@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 760b9b4f6d ]
If the device configuration fails (if `dma_dev->device_config()`),
`sg_dma_address(&sg)` is not initialized and the jump to `err_dma_prep`
leads to calling `dma_unmap_single()` on `sg_dma_address(&sg)`.
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250610142918.169540-2-fourier.thomas@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b367017cda ]
When an stp sync check is handled on a system with multiple
cpus each cpu gets a machine check but only the first one
actually handles the sync operation. All other CPUs spin
waiting for the first one to finish with a short udelay().
But udelay can't be used here as the first CPU modifies tod_clock_base
before performing the sync op. During this timeframe
get_tod_clock_monotonic() might return a non-monotonic time.
The time spent waiting should be very short and udelay is a busy loop
anyways, therefore simply remove the udelay.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b9e2f2246e ]
The thread flags may change during their processing.
For example a task_work can queue a new signal to be sent.
This signal should be delivered before returning to usespace again.
Evaluate the flags repeatedly similar to other architectures.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20250704-uml-thread_flags-v1-1-0e293fd8d627@linutronix.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d7ce7e3a84 ]
Set TAINT_MACHINE_CHECK when SError or Synchronous External Abort (SEA)
interrupts trigger a panic to flag potential hardware faults. This
tainting mechanism aids in debugging and enables correlation of
hardware-related crashes in large-scale deployments.
This change aligns with similar patches[1] that mark machine check
events when the system crashes due to hardware errors.
Link: https://lore.kernel.org/all/20250702-add_tain-v1-1-9187b10914b9@debian.org/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20250716-vmcore_hw_error-v2-1-f187f7d62aba@debian.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 09e7e29d2b ]
Otherwise the code might not work correctly when the clock
is changed.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9f85fdb9fc ]
The purpose of the warning is to prevent an unexpected change to the return
thunk mitigation. However, there are legitimate cases where the return
thunk is intentionally set more than once. For example, ITS and SRSO both
can set the return thunk after retbleed has set it. In both the cases
retbleed is still mitigated.
Replace the warning with an info about the active return thunk.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250611-eibrs-fix-v4-3-5ff86cac6c61@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7cdb433bb4 ]
In order to bring up secondary CPUs main CPU write trampoline
code to SRAM. The trampoline code is written while secondary
CPUs are powered on (at least that true for RK3188 CPU).
Sometimes that leads to kernel hang. Probably because secondary
CPU execute trampoline code while kernel doesn't expect.
The patch moves SRAM initialization step to the point where all
secondary CPUs are powered down.
That fixes rarely hangs on RK3188:
[ 0.091568] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[ 0.091996] rockchip_smp_prepare_cpus: ncores 4
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Link: https://lore.kernel.org/r/20250703140453.1273027-1-al.kochet@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
