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192,804 commits

Author SHA1 Message Date
Sean Christopherson
347201ced0 KVM: x86: Retry page fault if MMU reload is pending and root has no sp
[ Upstream commit 18c841e1f4 ]

Play nice with a NULL shadow page when checking for an obsolete root in
the page fault handler by flagging the page fault as stale if there's no
shadow page associated with the root and KVM_REQ_MMU_RELOAD is pending.
Invalidating memslots, which is the only case where _all_ roots need to
be reloaded, requests all vCPUs to reload their MMUs while holding
mmu_lock for lock.

The "special" roots, e.g. pae_root when KVM uses PAE paging, are not
backed by a shadow page.  Running with TDP disabled or with nested NPT
explodes spectaculary due to dereferencing a NULL shadow page pointer.

Skip the KVM_REQ_MMU_RELOAD check if there is a valid shadow page for the
root.  Zapping shadow pages in response to guest activity, e.g. when the
guest frees a PGD, can trigger KVM_REQ_MMU_RELOAD even if the current
vCPU isn't using the affected root.  I.e. KVM_REQ_MMU_RELOAD can be seen
with a completely valid root shadow page.  This is a bit of a moot point
as KVM currently unloads all roots on KVM_REQ_MMU_RELOAD, but that will
be cleaned up in the future.

Fixes: a955cad84c ("KVM: x86/mmu: Retry page fault if root is invalidated by memslot update")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211209060552.2956723-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-27 14:28:22 +02:00
Sean Christopherson
62ef67af18 KVM: x86: Check for invalid/obsolete root *after* making MMU pages available
[ Upstream commit 2abd5287f0 ]

Check for a "stale" page fault, i.e. for an invalid and/or obsolete root,
after making MMU pages available for the shadow MMU.  If reclaiming shadow
pages zaps an in-use root, i.e. marks it invalid, then KVM will attempt to
map memory into an invalid root.  On its own, populating an invalid root is
"fine", but because child shadow pages inherit their parent's role, any
children created during the map/fetch will be created as invalid pages,
thus violating KVM's invariant that invalid pages are never on the list of
active MMU pages.

Note, the underlying flaw has existed since KVM first started tracking
invalid roots in 2008 (commit 2e53d63acb, "KVM: MMU: ignore zapped root
pagetables"), but the true badness only came along in 2020 (Linux 5.9)
with the invariant that invalid shadow pages can't be on the list of
active pages.

Note #2, inheriting role.invalid when creating child shadow pages is also
far from ideal; that flaw will be addressed separately.

Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Fixes: f95eec9bed ("KVM: x86/mmu: Don't put invalid SPs back on the list of active pages")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[backport note: upstream passes struct kvm_page_fault to is_page_fault_stale();
 here individual parameters are used, as is_page_fault_stale() was
 backported with that interface in the preceding commit]
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:22 +02:00
David Matlack
c893b84a91 KVM: x86/mmu: Rename __direct_map() to direct_map()
[ Upstream commit 6c882ef4fc ]

Rename __direct_map() to direct_map() since the leading underscores are
unnecessary. This also makes the page fault handler names more
consistent: kvm_tdp_mmu_page_fault() calls kvm_tdp_mmu_map() and
direct_page_fault() calls direct_map().

Opportunistically make some trivial cleanups to comments that had to be
modified anyway since they mentioned __direct_map(). Specifically, use
"()" when referring to functions, and include kvm_tdp_mmu_map() among
the various callers of disallowed_hugepage_adjust().

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220921173546.2674386-11-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
David Matlack
851bb1a277 KVM: x86/mmu: Split out TDP MMU page fault handling
[ Upstream commit 9aa8ab43b3 ]

Split out the page fault handling for the TDP MMU to a separate
function.  This creates some duplicate code, but makes the TDP MMU fault
handler simpler to read by eliminating branches and will enable future
cleanups by allowing the TDP MMU and non-TDP MMU fault paths to diverge.

Only compile in the TDP MMU fault handler for 64-bit builds since
kvm_tdp_mmu_map() does not exist in 32-bit builds.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220921173546.2674386-9-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Chao Peng
29c0039ea1 KVM: Rename mmu_notifier_* to mmu_invalidate_*
[ Upstream commit 20ec3ebd70 ]

The motivation of this renaming is to make these variables and related
helper functions less mmu_notifier bound and can also be used for non
mmu_notifier based page invalidation. mmu_invalidate_* was chosen to
better describe the purpose of 'invalidating' a page that those
variables are used for.

  - mmu_notifier_seq/range_start/range_end are renamed to
    mmu_invalidate_seq/range_start/range_end.

  - mmu_notifier_retry{_hva} helper functions are renamed to
    mmu_invalidate_retry{_hva}.

  - mmu_notifier_count is renamed to mmu_invalidate_in_progress to
    avoid confusion with mn_active_invalidate_count.

  - While here, also update kvm_inc/dec_notifier_count() to
    kvm_mmu_invalidate_begin/end() to match the change for
    mmu_notifier_count.

No functional change intended.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Message-Id: <20220816125322.1110439-3-chao.p.peng@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Sean Christopherson
c602274e2b KVM: x86/mmu: Document the "rules" for using host_pfn_mapping_level()
[ Upstream commit 65e3b446bc ]

Add a comment to document how host_pfn_mapping_level() can be used safely,
as the line between safe and dangerous is quite thin.  E.g. if KVM were
to ever support in-place promotion to create huge pages, consuming the
level is safe if the caller holds mmu_lock and checks that there's an
existing _leaf_ SPTE, but unsafe if the caller only checks that there's a
non-leaf SPTE.

Opportunistically tweak the existing comments to explicitly document why
KVM needs to use READ_ONCE().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220715232107.3775620-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Sean Christopherson
94f50cc4f8 KVM: x86/mmu: Rename pte_list_{destroy,remove}() to show they zap SPTEs
[ Upstream commit 9202aee816 ]

Rename pte_list_remove() and pte_list_destroy() to kvm_zap_one_rmap_spte()
and kvm_zap_all_rmap_sptes() respectively to document that (a) they zap
SPTEs and (b) to better document how they differ (remove vs. destroy does
not exactly scream "one vs. all").

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220715224226.3749507-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Sean Christopherson
fde1c386a1 KVM: x86/mmu: Directly "destroy" PTE list when recycling rmaps
[ Upstream commit a42989e7fb ]

Use pte_list_destroy() directly when recycling rmaps instead of bouncing
through kvm_unmap_rmapp() and kvm_zap_rmapp().  Calling kvm_unmap_rmapp()
is unnecessary and odd as it requires passing dummy parameters; passing
NULL for @slot when __rmap_add() already has a valid slot is especially
weird and confusing.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220715224226.3749507-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2abd5287f0 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Sean Christopherson
b5093d507d KVM: x86/mmu: Retry page fault if root is invalidated by memslot update
[ Upstream commit a955cad84c ]

Bail from the page fault handler if the root shadow page was obsoleted by
a memslot update.  Do the check _after_ acuiring mmu_lock, as the TDP MMU
doesn't rely on the memslot/MMU generation, and instead relies on the
root being explicit marked invalid by kvm_mmu_zap_all_fast(), which takes
mmu_lock for write.

For the TDP MMU, inserting a SPTE into an obsolete root can leak a SP if
kvm_tdp_mmu_zap_invalidated_roots() has already zapped the SP, i.e. has
moved past the gfn associated with the SP.

For other MMUs, the resulting behavior is far more convoluted, though
unlikely to be truly problematic.  Installing SPs/SPTEs into the obsolete
root isn't directly problematic, as the obsolete root will be unloaded
and dropped before the vCPU re-enters the guest.  But because the legacy
MMU tracks shadow pages by their role, any SP created by the fault can
can be reused in the new post-reload root.  Again, that _shouldn't_ be
problematic as any leaf child SPTEs will be created for the current/valid
memslot generation, and kvm_mmu_get_page() will not reuse child SPs from
the old generation as they will be flagged as obsolete.  But, given that
continuing with the fault is pointess (the root will be unloaded), apply
the check to all MMUs.

Fixes: b7cccd397f ("KVM: x86/mmu: Fast invalidation for TDP MMU")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120045046.3940942-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[backport note: is_page_fault_stale() adapted to take individual parameters
 instead of struct kvm_page_fault, since 4326e57ef4 ("KVM: MMU: change
 direct_page_fault() arguments to kvm_page_fault") is not in 5.15.y;
 required by the following backport of 2abd5287f0 and by 0cb2af2ea6
 to be backported separately]
Assisted-by: Claude:claude-sonnet-4.6
Signed-off-by: Kenta Akagi <k@mgml.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-27 14:28:21 +02:00
Jon Hunter
0f75268098 arm64: tegra: Add EL2 virtual timer interrupt for Tegra194
[ Upstream commit a7c28483fd ]

Commit d87773de9e ("clocksource/drivers/arm_arch_timer: Default to EL2
virtual timer when running VHE") updated the ARM arch timer driver to
use the virtual timer by default if the CPU is running at EL2 with VHE
enabled. If the CPU is running at EL2 with VHE enabled but there is no
interrupt provided for the virtual timer, then the following warning is
displayed:

 arch_timer: [Firmware Bug]: VHE-capable CPU without EL2 virtual timer
  interrupt

This warning is observed on Tegra194 platforms. Tegra194 SoC includes
NVIDIA Carmel ARM v8.2 CPUs and support an EL2 virtual timer. Fix the
above warning by adding the PPI for the EL2 virtual timer interrupt for
Tegra194.

Fixes: 5425fb15d8 ("arm64: tegra: Add Tegra194 chip device tree")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-23 14:17:31 +02:00
Reinette Chatre
ad12e70d7d fs/resctrl: Fix double-add of pseudo-locked region's RMID to free list
[ Upstream commit b9f089723a ]

A pseudo-locked group's RMID is freed when it is created. On unmount
rmdir_all_sub() unconditionally frees all RMID of all groups, resulting
in a double-free of the pseudo-locked group's RMID. The consequence of this
is that the original free results in the pseudo-locked group's RMID being
added to the rmid_free_lru linked list and the second free then attempts
to add the same RMID entry to the rmid_free_lru again.

Do not double-free a pseudo-locked group's RMID.

Fixes: e0bdfe8e36 ("x86/intel_rdt: Support creation/removal of pseudo-locked region")
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/551432dd7e624a862b8e58314c38aaba0afff3e9.1783377598.git.reinette.chatre@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-23 14:17:24 +02:00
Ali Ahmet Memis
cf1b5514dd openrisc: signal: do not restore privileged SR bits on sigreturn
commit 32ef1b30ad upstream.

restore_sigcontext() copies the whole supervision register (SR) from the
signal frame and only clears SPR_SR_SM before the value is reloaded into
the hardware SR (through ESR and l.rfe) on the return to user space.  All
other SR bits are left under user control.

An unprivileged task can thus return from a signal handler through a
crafted sigframe that clears SPR_SR_DME.  With the data MMU disabled the
CPU performs no translation or protection on data accesses, so the task
gains read and write access to arbitrary physical memory, a local
privilege escalation.  SPR_SR_IME, SPR_SR_SUMRA, SPR_SR_LEE, SPR_SR_EPH
and the cache-enable bits are exposed the same way.  The ptrace GPR regset
already refuses any change to SR for exactly this reason.

Restore only the arithmetic flag bits (F, CY, OV) from the signal frame
and take every privileged control bit from the SR the kernel saved on
signal entry.

Verified with qemu-system-or1k -M or1k-sim: before this change an
unprivileged PoC clears SPR_SR_DME in rt_sigreturn and writes a marker to
physical address 0x03000000 (beyond the kernel's mem=32M); afterwards the
same PoC receives SIGSEGV and physical memory is unchanged.

Fixes: ac689eb7f9 ("OpenRISC: Signal handling")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-23 14:17:16 +02:00
George Wilson
f72ecff768 powerpc/pseries: lparcfg - fix kbuf[] underflow
commit fb442a6673 upstream.

In lparcfg_write(), a count of 0 results in kbuf[] being indexed at -1.
Check for count == 0 in the existing check for count > sizeof(kbuf) and
return -EINVAL if true.

Fixes: 74422e2b19 ("powerpc/pseries: Remove VLA from lparcfg_write()")
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 4.20
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-23 14:17:15 +02:00
George Wilson
4646da41f5 powerpc/pseries: pci - logic bug
commit 649c10bff5 upstream.

The checks on num_vfs in pseries_pci_sriov_enable() are ANDed where OR
was apparently intended.  Change it to OR.

Fixes: 9a7f6b4386 ("powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV")
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-23 14:17:15 +02:00
Yuho Choi
5da03db106 ARM: npcm: Fix OF node refcount leaks in SMP setup
[ Upstream commit 8eb052f483 ]

npcm7xx_smp_boot_secondary() and npcm7xx_smp_prepare_cpus() look up
the GCR and SCU nodes with of_find_compatible_node(). The returned
nodes are used for of_iomap(), but the node references are never
released.

of_iomap() does not consume the device node reference, and iounmap()
only releases the MMIO mapping. Drop each node reference after the
corresponding mapping attempt.

Fixes: 7bffa14c9a ("arm: npcm: add basic support for Nuvoton BMCs")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Reviewed-by: Avi Fishman <avifishman70@gmail.com>
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:14:13 +02:00
Michael Bommarito
a7bc015bb7 um: vector: fix use-after-free in vector_mmsg_rx()
commit af421e9aed upstream.

When vector_mmsg_rx() discards a packet whose overlay header fails
verify_header(), it frees the skb and continues the loop:

	if (header_check < 0) {
		dev_kfree_skb_irq(skb);
		vp->estats.rx_encaps_errors++;
		continue;
	}

The normal and short-packet paths fall through to the bottom of the
loop body, which clears the consumed slot and advances the cursors:

	(*skbuff_vector) = NULL;
	mmsg_vector++;
	skbuff_vector++;

The verify_header() < 0 path skips that via continue, so the freed skb
is left in skbuff_vector[] and the cursors do not advance. The next
iteration reads the same slot, gets the freed skb, and frees it again,
producing a refcount underflow / use-after-free in the RX path.

Discard the slot the same way the other paths do before continuing.

Only transports whose verify_header() can return negative are affected:
GRE and L2TPv3 do so on a cookie/session-id mismatch (raw/tap do not),
so any peer on such a transport can trigger it without authentication.

Fixes: 49da7e64f3 ("High Performance UML Vector Network Driver")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:14:10 +02:00
Thorsten Blum
92c4cae659 powerpc/ps3: Fix map failure path in dma_ioc0_map_pages()
commit 0bb024f11d upstream.

If lv1_put_iopte() fails in dma_ioc0_map_pages(), the error path
decrements iopage but keeps using the failed mapping's offset. As a
result, it repeatedly tries to invalidate the failed IOPTE slot and
leaves the already installed IOPTEs valid.

Recompute offset and invalidate the installed IOPTEs instead.

Fixes: 6bb5cf1025 ("[POWERPC] PS3: System-bus rework")
Cc: stable@vger.kernel.org
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260711130931.740719-3-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:14:10 +02:00
Thorsten Blum
8bdfe68ac8 powerpc/boot: Fix treeboot-akebono CPU node lookup check
[ Upstream commit b24fc8278b ]

fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: 2a2c74b2ef ("IBM Akebono: Add the Akebono platform")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-6-thorsten.blum@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:14:07 +02:00
Thorsten Blum
f725afafb8 powerpc/boot: Fix treeboot-currituck CPU node lookup check
[ Upstream commit 43863f6575 ]

fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: 228d550533 ("powerpc/47x: Add support for the new IBM currituck platform")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-5-thorsten.blum@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:14:07 +02:00
Thorsten Blum
60d03367c5 powerpc/boot: Fix simpleboot CPU node lookup check
[ Upstream commit c824ab6568 ]

fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: d2477b5cc8 ("[POWERPC] bootwrapper: Add a firmware-independent simpleboot target.")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-4-thorsten.blum@linux.dev
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:14:07 +02:00
Will Deacon
7ec6eebb43 Revert "arm64: syscall: Ensure saved x0 is kept in-sync with tracer updates"
commit 26b483d524 upstream.

This reverts commit e057b94772.

Sashiko points out that updating 'orig_x0' after secure_computing()
has returned is too late to handle the case where a seccomp filter is
re-evaluated after initially returning SECCOMP_RET_TRACE. This means
that a tracer can manipulate the first argument of the syscall behind
seccomp's back.

For now, revert the initial fix and we'll have another crack at it soon.
Since the incorrect fix was cc'd to stable, do the same here with an
appropriate fixes tag.

Cc: stable@vger.kernel.org
Fixes: e057b94772 ("arm64: syscall: Ensure saved x0 is kept in-sync with tracer updates")
Link: https://sashiko.dev/#/patchset/20260716120640.6590-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:14:03 +02:00
Will Deacon
6b3325c5ed arm64: syscall: Ensure saved x0 is kept in-sync with tracer updates
commit e057b94772 upstream.

When seccomp support was originally added to arm64 in a1ae65b219
("arm64: add seccomp support"), seccomp was erroneously called _before_
the ptrace syscall-enter-stop and therefore the tracer could trivially
manipulate the syscall register state after the seccomp check had
passed. This was subsequently fixed in a5cd110cb8 ("arm64/ptrace: run
seccomp after ptrace") by moving the seccomp check after the tracer has
run. Unfortunately, a decade later, that fix has been reported to be
incomplete.

On arm64, both the first argument to a syscall and its eventual return
value are allocated to register x0. In order to facilitate syscall
restarting and querying of syscall arguments on the syscall exit path,
the original value of x0 is stashed in 'struct pt_regs::orig_x0' early
during the syscall entry path and is returned for the first argument by
syscall_get_arguments(). Unlike 32-bit Arm, this stashed value is not
directly exposed via ptrace() and so changes to register x0 made by the
tracer on a syscall-enter-stop are not reflected in 'orig_x0'. This
means that seccomp, syscall tracepoints and audit can observe a stale
value for the register compared to the argument that will be observed by
the actual syscall.

Re-sync 'orig_x0' from x0 on the syscall entry path following a
potential ptrace stop (i.e. PTRACE_EVENTMSG_SYSCALL_ENTRY or
SECCOMP_RET_TRACE). This behaviour is limited to native tasks (because
compat tasks expose 'orig_r0' to ptrace) where the syscall is not being
skipped (because x0 is updated to hold the return value of -ENOSYS in
that case).

Cc: Kees Cook <kees@kernel.org>
Cc: Jinjie Ruan <ruanjinjie@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Reported-by: Yiqi Sun <sunyiqixm@gmail.com>
Link: https://lore.kernel.org/all/20260529065444.1336608-1-sunyiqixm@gmail.com/
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: a5cd110cb8 ("arm64/ptrace: run seccomp after ptrace")
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Tested-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:14:03 +02:00
Nathan Chancellor
f32620ba6a x86/boot/compressed: Disable jump tables
commit 4a9ec5ec95 upstream.

After a recent upstream LLVM change to start generating jump and lookup
tables in switch statements in more instances [1], linking the
compressed x86 boot image when CONFIG_KERNEL_ZSTD is enabled fails with:

  ld.lld: error: Unexpected run-time relocations (.rela) detected!

Dumping the relocations in misc.o, which is the only file influenced by
CONFIG_KERNEL_ZSTD in the decompressor, shows dynamic relocations to
some string constants, which correspond to the string literals in the
switch statement in handle_zstd_error():

  Relocation section '.rela.data.rel.ro' at offset 0x277b0 contains 31 entries:
      Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
  0000000000000000  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 73a
  0000000000000008  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  0000000000000010  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  0000000000000018  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  ...

This optimization is problematic for the decompressor environment, as it
is built as -fPIE without any explicit absolute references (as described
at the top of misc.c) while not applying any dynamic relocations, hence
the linker assertion. To opt out of this optimization, which is of
little value in this special early boot code, and to mirror the other
x86 startup code in arch/x86/boot/startup, disable jump tables in the
decompressor.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: fa02a6ed66 [1]
Link: https://patch.msgid.link/20260722-x86-boot-compressed-disable-jt-clang-v2-1-7373d38482fb@kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2165
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:14:02 +02:00
Shrikanth Hegde
406141d506 powerpc/vtime: Initialize starttime at boot for native accounting
[ Upstream commit c1c1ffa490 ]

It was observed that /proc/stat had very large value for one ore more
CPUs. It was more visible after recent code simplifications around
cpustats.

System has 240 CPUs.

cat /proc/uptime;
194.18 46500.55
cat /proc/stat
cpu  5966 39 837032887 4650070 164 185 100 0 0 0
cpu0 108 0 837030890 19109 24 4 23 0 0 0

Since uptime is 194s, system time of each CPU can't be more than 19400.
Sum of system time  of all CPUs can't be more than 19400*240 4656000.
In fact huge value is close to mftb(). Note mftb doesn't reset on powerVM
when the LPAR restart. It only resets when whole system resets. The same
issue exists for kexec too.

This happens since starttime is not setup at init time. Once it is set
then subsequent vtime_delta will return the right delta.

Fix it by initializing the starttime during CPU initialization. This
fixes the large times seen.

cat /proc/uptime; cat /proc/stat
15.78 3694.63
cpu  6035 35 1347 369479 23 144 49 0 0 0
cpu0 19 0 38 1508 0 1 14 0 0 0

Now, system time is reported as expected.

Fixes: cf9efce0ce ("powerpc: Account time using timebase rather  than PURR")
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Suggested-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260605124329.377533-1-sshegde@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:54 +02:00
Frederic Weisbecker
865777d8d5 powerpc/time: Prepare to stop elapsing in dynticks-idle
[ Upstream commit c8ba971cf8 ]

Currently the tick subsystem stores the idle cputime accounting in
private fields, allowing cohabitation with architecture idle vtime
accounting. The former is fetched on online CPUs, the latter on offline
CPUs.

For consolidation purpose, architecture vtime accounting will continue
to account the cputime but will make a break when the idle tick is
stopped. The dyntick cputime accounting will then be relayed by the tick
subsystem so that the idle cputime is still seen advancing coherently
even when the tick isn't there to flush the idle vtime.

Prepare for that and introduce three new APIs which will be used in
subsequent patches:

  - vtime_dynticks_start() is deemed to be called when idle enters in
    dyntick mode. The idle cputime that elapsed so far is accumulated.

  - vtime_dynticks_stop() is deemed to be called when idle exits from
    dyntick mode. The vtime entry clocks are fast-forward to current time
    so that idle accounting restarts elapsing from now.

  - vtime_reset() is deemed to be called from dynticks idle IRQ entry to
    fast-forward the clock to current time so that the IRQ time is still
    accounted by vtime while nohz cputime is paused.

Also accumulated vtime won't be flushed from dyntick-idle ticks to avoid
accounting twice the idle cputime, along with nohz accounting.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Link: https://patch.msgid.link/20260508131647.43868-6-frederic@kernel.org
Stable-dep-of: c1c1ffa490 ("powerpc/vtime: Initialize starttime at boot for native accounting")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:54 +02:00
Alexander Gordeev
f4b5a7d855 sched/vtime: Get rid of generic vtime_task_switch() implementation
[ Upstream commit 89d6910cc5 ]

The generic vtime_task_switch() implementation gets built only
if __ARCH_HAS_VTIME_TASK_SWITCH is not defined, but requires an
architecture to implement arch_vtime_task_switch() callback at
the same time, which is confusing.

Further, arch_vtime_task_switch() is implemented for 32-bit PowerPC
architecture only and vtime_task_switch() generic variant is rather
superfluous.

Simplify the whole vtime_task_switch() wiring by moving the existing
generic implementation to PowerPC.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2cb6e3caada93623f6d4f78ad938ac6cd0e2fda8.1712760275.git.agordeev@linux.ibm.com
Stable-dep-of: c1c1ffa490 ("powerpc/vtime: Initialize starttime at boot for native accounting")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:54 +02:00
Nicholas Piggin
2011951737 powerpc: remove the last remnants of cputime_t
[ Upstream commit f985adaf2f ]

cputime_t was a core kernel type, removed by commits
ed5c8c854f2b..b672592f0221. As explained in commit b672592f02
("sched/cputime: Remove generic asm headers"), the final cleanup
is for the arch to provide cputime_to_nsec[s](). Commit ade7667a98
("powerpc: Add cputime_to_nsecs()") did that, but justdidn't remove
the then-unused cputime_to_usecs(), cputime_t type, and associated
remnants.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221006105653.115829-1-npiggin@gmail.com
Stable-dep-of: c1c1ffa490 ("powerpc/vtime: Initialize starttime at boot for native accounting")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:54 +02:00
He Ying
22801da2f8 powerpc/time: Fix sparse warnings
[ Upstream commit ce0091a0e0 ]

We found these warnings in arch/powerpc/kernel/time.c as follows:
  warning: symbol 'decrementer_max' was not declared. Should it be static?
  warning: symbol 'rtc_lock' was not declared. Should it be static?
  warning: symbol 'dtl_consumer' was not declared. Should it be static?

Declare 'decrementer_max' in powerpc asm/time.h.

Include linux/mc146818rtc.h in powerpc kernel/time.c where 'rtc_lock' is
declared. And remove duplicated declaration of 'rtc_lock' in powerpc
platforms/chrp/time.c because it has included linux/mc146818rtc.h.

Move 'dtl_consumer' definition after "include <asm/dtl.h>" because it is
declared there.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210324090939.143477-1-heying24@huawei.com
Stable-dep-of: c1c1ffa490 ("powerpc/vtime: Initialize starttime at boot for native accounting")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:54 +02:00
Sean Christopherson
fc71c00ad5 KVM: VMX: Make vmread_error_trampoline() uncallable from C code
[ Upstream commit 0b5e7a16a0 ]

Declare vmread_error_trampoline() as an opaque symbol so that it cannot
be called from C code, at least not without some serious fudging.  The
trampoline always passes parameters on the stack so that the inline
VMREAD sequence doesn't need to clobber registers.  regparm(0) was
originally added to document the stack behavior, but it ended up being
confusing because regparm(0) is a nop for 64-bit targets.

Opportunustically wrap the trampoline and its declaration in #ifdeffery
to make it even harder to invoke incorrectly, to document why it exists,
and so that it's not left behind if/when CONFIG_CC_HAS_ASM_GOTO_OUTPUT
is true for all supported toolchains.

No functional change intended.

Cc: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220928232015.745948-1-seanjc@google.com
[ Vivian: Adjust context. Remove check for CONFIG_CC_HAS_ASM_GOTO_OUTPUT
  which does not apply for old kernel. ]
Signed-off-by: Vivian Wang <dramforever@live.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-08-19 17:13:52 +02:00
Phil Rosenthal
42272b0f23 KVM: x86/mmu: Fix use-after-free on vendor module reload
commit 52f2f7c301 upstream.

mmu_destroy_caches() destroys pte_list_desc_cache and
mmu_page_header_cache, but leaves both pointers unchanged.  The pointers
live in kvm.ko, and therefore survive when a vendor module is unloaded
while kvm.ko remains loaded.

If creation of pte_list_desc_cache fails during a subsequent vendor
module load, its assignment sets pte_list_desc_cache to NULL and the
error path calls mmu_destroy_caches().  mmu_page_header_cache still
points to the cache destroyed during the preceding vendor module
unload.  Passing that stale pointer to kmem_cache_destroy() causes a
slab use-after-free.

Reproduce the issue on a v7.1.3 kernel with CONFIG_KASAN=y,
CONFIG_KASAN_GENERIC=y, CONFIG_KVM=m, and CONFIG_KVM_INTEL=m.  A
one-shot test hook forces pte_list_desc_cache to NULL on the second
invocation of kvm_mmu_vendor_module_init():

  1. Load kvm.ko and kvm-intel.ko, creating both caches.
  2. Unload only kvm_intel, leaving kvm.ko loaded.
  3. Reload kvm_intel and force initialization through the -ENOMEM path.

KASAN reports:

  BUG: KASAN: slab-use-after-free in
  kvm_mmu_vendor_module_init+0x5b/0x170 [kvm]
  ...
  kmem_cache_destroy+0x21/0x1d0
  kvm_mmu_vendor_module_init+0x5b/0x170 [kvm]
  ...
  Allocated by task 16817:
  __kmem_cache_create_args+0x12c/0x3b0
  __kmem_cache_create.constprop.0+0xb6/0xf0 [kvm]
  kvm_mmu_vendor_module_init+0x13b/0x170 [kvm]
  ...
  Freed by task 16820:
  kmem_cache_destroy+0x117/0x1d0
  kvm_mmu_vendor_module_exit+0x21/0x30 [kvm]

Clear both pointers immediately after destroying their caches so that
the stored state reflects the caches' lifetime and repeated cleanup is
safe.

With the fix applied, the same injected vendor module reload fails with
-ENOMEM as expected and produces no KASAN report.

Fixes: cb498ea2ce ("KVM: Portability: Combine kvm_init and kvm_init_x86")
Cc: stable@vger.kernel.org
Signed-off-by: Phil Rosenthal <phil@phil.gs>
Message-ID: <20260718-kvm-mmu-cache-uaf-v3-1-e103b93c74e1@phil.gs>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:13:51 +02:00
Hyunwoo Kim
4f50e6aec1 KVM: nVMX: Hide shadow VMCS right after VMCLEAR
commit 622ebfac01 upstream.

free_nested() frees the shadow VMCS while vmcs01 still points to it. But
because it is asynchronous with respect to loaded_vmcs_clear(), the vCPU
might migrate before the pointer is cleared and __loaded_vmcs_clear()
may then execute VMCLEAR.

The VMCS needs to stay attached until its explicit VMCLEAR completes, but
then it can be hidden and the page safely freed.

Fixes: 355f4fb140 ("kvm: nVMX: VMCLEAR an active shadow VMCS after last use")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-19 17:13:51 +02:00
Borislav Petkov (AMD)
52db77a13b x86/bugs: Make Safe-RET robust against interrupt injection
An attacker injecting interrupts while the Safe-RET mitigation executes
on machines affected by SRSO can neutralize the safe return sequence,
potentially leading to data leakage through speculative execution.

Fixup register state as if the Safe-RET sequence executed successfully
by "emulating" it, in a manner of speaking, and avoid executing a RET
instruction after returning from the interrupt.

Co-developed-by: David Kaplan <David.Kaplan@amd.com>
Signed-off-by: David Kaplan <David.Kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Wenkuan Wang <Wenkuan.Wang@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-07 08:07:31 +02:00
Greg Kroah-Hartman
41285da140 Revert "x86/bugs: Make Safe-RET robust against interrupt injection"
This reverts commit 9c0b8105e9 which is
commit 7e7f81cf6f upstream.

It was incorrect, a more correct fix will be applied next.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-07 08:07:31 +02:00
Borislav Petkov (AMD)
9c0b8105e9 x86/bugs: Make Safe-RET robust against interrupt injection
commit 7e7f81cf6f upstream.

An attacker injecting interrupts while the Safe-RET mitigation executes
on machines affected by SRSO can neutralize the safe return sequence,
potentially leading to data leakage through speculative execution.

Fixup register state as if the Safe-RET sequence executed successfully
by "emulating" it, in a manner of speaking, and avoid executing a RET
instruction after returning from the interrupt.

Co-developed-by: David Kaplan <David.Kaplan@amd.com>
Signed-off-by: David Kaplan <David.Kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-06 19:22:14 +02:00
Sandipan Das
ddec1ef725 perf/x86/amd/core: Always use the NMI latency mitigation
commit 73a4c02f94 upstream.

Commit df4d29732f ("perf/x86/amd: Change/fix NMI latency mitigation
to use a timestamp") fixed handling of late-arriving NMIs but limited
the mitigation to processors having X86_FEATURE_PERFCTR_CORE. However,
it is unclear if processors without this feature are also affected.
When Mediated vPMU is enabled on affected hardware, it is also possible
to bypass the fix inside KVM guests if X86_FEATURE_PERFCTR_CORE is
removed from the guest CPUID (e.g. using "-cpu host,-perfctr-core" with
QEMU). Hence, use the mitigation at all times.

Fixes: df4d29732f ("perf/x86/amd: Change/fix NMI latency mitigation to use a timestamp")
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/29a3c970da289ab8f24282933bdb36545c0403e8.1780325517.git.sandipan.das@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:52:02 +02:00
Marc Zyngier
1b4a3c2f05 KVM: Move kvm_io_bus_get_dev() locking responsibilities to callers
commit 3a07249981 upstream.

kvm_io_bus_get_dev() returns a device that is only matched by the
address, and nothing else. This can cause a lifetime issue if
the matched device is not the expected type, as by the time
the caller can introspect the object, it might be gone (the srcu
lock having been dropped).

Given that there is only a single user of this helper, the simplest
option is to move the locking responsibility to the caller, which
can keep the srcu lock held for as long as it wants.

Note that this aligns with other kvm_io_bus*() helpers, which
already require the srcu lock to be held by the callers.

Reported-by: Will Deacon <will@kernel.org>
Fixes: 8a39d00670 ("KVM: kvm_io_bus: Add kvm_io_bus_get_dev() call")
Link: https://lore.kernel.org/all/20260626111344.802555-1-maz@kernel.org
Cc: stable@vger.kernel.org
Reviewed-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20260627105105.1005990-1-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:52:02 +02:00
Uwe Kleine-König
fc99a77aa2 gpio: pca953x: Make platform teardown callback return void
[ Upstream commit 6a8f359c31 ]

All platforms that provide a teardown callback return 0. New users are
supposed to not make use of platform support, so there is no
functionality lost.

This patch is a preparation for making i2c remove callbacks return void.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Stable-dep-of: 1f0bdc2884 ("usb: typec: ucsi: ccg: Fix use-after-free of ucsi on remove")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:52:01 +02:00
Junrui Luo
d479a7711f powerpc/spufs: fix out-of-bounds access in spufs_mem_mmap_access()
commit 47b87f469a upstream.

spufs_mem_mmap_access() computes the local store offset as
address - vma->vm_start, but bounds-checks it against vma->vm_end
instead of the local store size. On 64-bit, offset is always well
below vma->vm_end, so the clamp never fires and len stays unbounded
against the LS_SIZE buffer returned by ctx->ops->get_ls().

Reject offsets at or beyond LS_SIZE and clamp len to the remaining
space, mirroring the guard already used by spufs_mem_mmap_fault() and
spufs_ps_fault().

Fixes: a352894d07 ("spufs: use new vm_ops->access to allow local state access from gdb")
Reported-by: Yuhao Jiang <danisjiang@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/SYBPR01MB7881EE775E8B51C09F5A29E7AF152@SYBPR01MB7881.ausprd01.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:55 +02:00
Tao Liu
606cc45e87 riscv: Prevent NULL pointer dereference in machine_kexec_prepare()
commit 81bbcff0c0 upstream.

A NULL pointer dereference issue is noticed in riscv's
machine_kexec_prepare(), where image->segment[i].buf might be NULL and
copied unchecked.

The NULL buf comes from ima_add_kexec_buffer(), where kbuf is added by
kexec_add_buffer(), but kbuf.buffer is NULL, then it is copied without
a check in machine_kexec_prepare():

  kexec_file_load
    -> kimage_file_alloc_init()
       -> kimage_file_prepare_segments()
          -> ima_add_kexec_buffer()
             -> kexec_add_buffer()
    -> machine_kexec_prepare()
       -> memcpy()

Address this by adding a check before the data copy attempt.

Fixes: b7fb4d78a6 ("RISC-V: use memcpy for kexec_file mode")
Cc: stable@vger.kernel.org
Closes: https://lore.kernel.org/kexec/CAO7dBbVftLUhd2qrh7hmijTB3PEPfZAhykCGqEfrPoOcSrrj-w@mail.gmail.com/
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Nutty Liu <nutty.liu@hotmail.com>
Signed-off-by: Tao Liu <ltao@redhat.com>
Link: https://patch.msgid.link/20260705232706.30265-2-ltao@redhat.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:54 +02:00
Aaron Tomlin
d20ee42f82 mips: sched: Fix CPUMASK_OFFSTACK memory corruption
commit 98e37db4a3 upstream.

This patch addresses a critical memory management flaw. When
CONFIG_CPUMASK_OFFSTACK is enabled, cpumask_var_t is a pointer.
Consequently, sizeof(new_mask) evaluates to the pointer size, causing
copy_from_user() to clobber the mask pointer. Furthermore, the old
logic performed copy_from_user() before allocating the mask.

Fix this by allocating new_mask first. To handle variable-sized user
masks correctly, use cpumask_size() to truncate overly large user masks
or pad undersized masks with zeros before copying the data directly into
the allocated buffer.

Fixes: 295cbf6d63 ("[MIPS] Move FPU affinity code into separate file.")
Cc: stable@vger.kernel.org
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:49 +02:00
Maciej W. Rozycki
3394757c5d MIPS: DEC: Ensure 32-bit stack location for o32 prom_printf()
commit 5ff79e8bdc upstream.

In 64-bit configurations calling any firmware entry points from a kernel
thread other than the initial one will result in a situation where the
stack has been placed in the XKPHYS 64-bit memory segment.

Consequently the stack pointer is no longer a 32-bit value and when the
32-bit firmware code called uses 32-bit ALU operations to manipulate the
stack pointer, the calculated result is incorrect (in fact in the 64-bit
MIPS ISA almost all 32-bit ALU operations will produce an unpredictable
result when executed on 64-bit data) and control goes astray.

This may happen when no final console driver has been enabled in the
configuration and consequently the initial console continues being used
late into bootstrap, or with an upcoming change that will switch the zs
driver to use a platform device, which in turn will make the console
handover happen only after other kernel threads have already been
started, and the kernel will hang at:

  pid_max: default: 32768 minimum: 301

or somewhat later, but always before:

  cblist_init_generic: Setting adjustable number of callback queues.

has been printed.

It seems that only the prom_printf() entry point is affected.  Of all
the other entry points wired only rex_slot_address() and rex_gettcinfo()
are called from a kernel thread other than the initial one, specifically
kernel_init(), and they are leaf functions that do no business with the
stack, having worked with no issue ever since 64-bit support was added
for the platform back in 2002.

To address this issue then, arrange for the stack to be switched in the
o32 wrapper as required for prom_printf() only, by supplying call_o32()
with a pointer to a chunk of initdata space, which is placed in the
CKSEG0 32-bit compatibility segment, observing that prom_printf() is
only called from console output handler and therefore with the console
lock held, implying no need for this code to be reentrant.

Other firmware entry points may be called with interrupts enabled and no
lock held, and may therefore require that call_o32() be reentrant.  They
trigger no issue at this point and "if it ain't broke, don't fix it," so
just leave them alone.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Cc: stable@vger.kernel.org # v2.6.12+
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:49 +02:00
Johan Hovold
53b6f3593d MIPS: ip22-gio: fix device reference leak in probe
commit b82930a4c5 upstream.

The gio probe function needlessly takes a device reference which is
never released and therefore prevents unbound gio devices from being
freed.

Fixes: e84de0c619 ("MIPS: GIO bus support for SGI IP22/28")
Cc: stable@vger.kernel.org	# 3.3
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:49 +02:00
Johan Hovold
77b614016d MIPS: ip22-gio: fix kfree() of static object
commit c62cdd3e91 upstream.

The gio bus root device is a statically allocated object which must not
be freed by kfree() on failure to register the device or bus.

Fixes: 82242d28ff ("MIPS: IP22: Add missing put_device call")
Cc: stable@vger.kernel.org	# 3.17
Cc: Levente Kurusa <levex@linux.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:49 +02:00
Johan Hovold
9e74ea4769 MIPS: ip22-gio: fix gio device memory leak
commit 7de9a1b45f upstream.

The gio device release callback was never wired up so gio devices are
not freed when the last reference is dropped.

Fixes: e84de0c619 ("MIPS: GIO bus support for SGI IP22/28")
Cc: stable@vger.kernel.org	# 3.3
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:48 +02:00
Thorsten Blum
b6c0e07d66 x86/boot: Reject too long acpi_rsdp= values
commit d130041a7b upstream.

cmdline_find_option() returns the full length of the parsed acpi_rsdp=
value. get_cmdline_acpi_rsdp() then silently truncates values which do
not fit in the val[] buffer.

Prevent boot_kstrtoul() from parsing a truncated value and then the
kernel from silently using the wrong RSDP address, see discussion in
Link:.

Issue a warning so that the user is aware that s/he supplied a malformed
value and can get feedback instead of silent crashes.

  [ bp: Make commit message more precise. ]

Fixes: 3c98e71b42 ("x86/boot: Add "acpi_rsdp=" early parsing")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20260617130417.36651-4-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:47 +02:00
Thorsten Blum
24fbed0a2a x86/boot: Validate console=uart8250 baud rate to fix early boot hang
commit ffa0aa5b62 upstream.

When the baud rate is empty, 0, invalid, or overflows to 0 when stored
as an int, the system will hang during early boot because of a division
by zero in early_serial_init().

Fall back to DEFAULT_BAUD when the resulting baud rate is 0 to prevent
an early system hang.

Fixes: ce0aa5dd20 ("x86, setup: Make the setup code also accept console=uart8250")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260713194924.126472-3-thorsten.blum@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:47 +02:00
Hyunwoo Kim
cb3efe1a35 KVM: arm64: vgic: Check the interrupt is still ours before migrating it
commit 0074b82cdf upstream.

vgic_prune_ap_list() drops both ap_list_lock and irq_lock while migrating
an interrupt to another vCPU. After reacquiring the locks it only checks
that the affinity is unchanged (target_vcpu == vgic_target_oracle(irq))
before moving the interrupt, which assumes that an interrupt whose affinity
is preserved is still queued on this vCPU's ap_list.

That assumption no longer holds if the interrupt is taken off the ap_list
while the locks are dropped. vgic_flush_pending_lpis() removes the
interrupt from the list and sets irq->vcpu to NULL, but leaves
enabled/pending/target_vcpu untouched. As the interrupt is still enabled
and pending, vgic_target_oracle() returns the same target_vcpu, so the
affinity check passes and list_del() is run a second time on an entry that
has already been removed.

Also check that the interrupt is still assigned to this vCPU
(irq->vcpu == vcpu) before moving it.

Fixes: 0919e84c0f ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework")
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Link: https://patch.msgid.link/aiHnI1mu6SGQrgnz@v4bel
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:46 +02:00
Nickolay Goppen
625f9cc659 arm64: dts: qcom: sdm630: describe adsp_mem region properly
commit ce414263e9 upstream.

Downstream [1] this region is marked as shared, reusable and dynamic so
describe it that way.

[1]: https://github.com/xiaomi-sdm660/android_kernel_xiaomi_sdm660/blob/11-EAS/arch/arm/boot/dts/qcom/sdm660.dtsi#L448

Fixes: b190fb0106 ("arm64: dts: qcom: sdm630: Add sdm630 dts file")
Cc: stable@vger.kernel.org
Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Nickolay Goppen <setotau@mainlining.org>
Link: https://lore.kernel.org/r/20260429-qcom-sdm660-cdsp-adsp-fastrpc-dts-fix-v5-4-16bc82e622ad@mainlining.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-24 15:51:46 +02:00
Anshuman Khandual
ef80b36ff4 arm64/mm: Optimize TLB flush in unmap_hotplug_[pmd|pud]_range()
[ Upstream commit ff4c5a0de1 ]

Commit 48478b9f79 ("arm64/mm: Enable batched TLB flush in
unmap_hotplug_range") inadvertently introduced redundant TLB
invalidation when clearing a block entry, resulting in unnecessary
broadcast invalidation on CPUs without support for range-based
invalidation.

Re-introduce the old behaviour, along with some expanded comments to
help people working in this area next time around.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Closes: https://lore.kernel.org/all/b0d5836032ce3135bfc473f6bff791306d086925.camel@decadent.org.uk/
Fixes: 48478b9f79 ("arm64/mm: Enable batched TLB flush in unmap_hotplug_range()")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[will: Reword comments and commit message]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-07-24 15:51:43 +02:00
Krzysztof Wilczyński
dcb638b472 alpha/PCI: Fix __pci_mmap_fits() overflow for zero-length BARs
[ Upstream commit 802a3b3f47 ]

Currently, __pci_mmap_fits() computes the BAR size using
"pci_resource_len() - 1", which wraps to a large value when the BAR length
is zero, causing the bounds check to incorrectly succeed.

Add an early return for empty resources.

Fixes: 10a0ef39fb ("PCI/alpha: pci sysfs resources")
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://patch.msgid.link/20260508043543.217179-15-kwilczynski@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-07-24 15:51:41 +02:00