Merge branch 'next' into for-linus

Prepare input updates for 6.11 merge window.

Merge tag 'v6.9' into next

Sync up with the mainline to bring in the new cleanup API.

Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch

Conflicts:
arch/x86/include/asm/percpu.h
arch/x86/include/asm/text-patching.h

Signed-off-by: Ingo Molnar <mingo@k

Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch

Conflicts:
arch/x86/include/asm/percpu.h
arch/x86/include/asm/text-patching.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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Merge drm/drm-next into drm-intel-gt-next

Work that needs to land in drm-intel-gt-next depends on two patches only
present in drm-intel-next, absence of which is causing a merge conflict:

3b918f4

Merge drm/drm-next into drm-intel-gt-next

Work that needs to land in drm-intel-gt-next depends on two patches only
present in drm-intel-next, absence of which is causing a merge conflict:

3b918f4f0c8b ("drm/i915/pxp: Optimize GET_PARAM:PXP_STATUS")
ac765b7018f6 ("drm/i915/pxp/mtl: intel_pxp_init_hw needs runtime-pm inside pm-complete")

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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Merge branch 'for-6.7/config_pm' into for-linus

- #ifdef CONFIG_PM removal from HID code (Thomas Weißschuh)

Merge branch 'linus' into smp/core

Pull in upstream to get the fixes so depending changes can be applied.

Merge drm/drm-next into drm-misc-next

Updating drm-misc-next to the state of Linux v6.6-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'v6.6-rc4' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'v6.6-rc2' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge drm/drm-next into drm-intel-next

Sync to v6.6-rc1.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR.

No conflicts.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'x86-urgent-2023-09-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
"Fix preemption delays in the SGX code, remove unnecessarily
UAPI-expor

Merge tag 'x86-urgent-2023-09-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
"Fix preemption delays in the SGX code, remove unnecessarily
UAPI-exported code, fix a ld.lld linker (in)compatibility quirk and
make the x86 SMP init code a bit more conservative to fix kexec()
lockups"

* tag 'x86-urgent-2023-09-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sgx: Break up long non-preemptible delays in sgx_vepc_release()
x86: Remove the arch_calc_vm_prot_bits() macro from the UAPI
x86/build: Fix linker fill bytes quirk/incompatibility for ld.lld
x86/smp: Don't send INIT to non-present and non-booted CPUs

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x86: Remove the arch_calc_vm_prot_bits() macro from the UAPI

The arch_calc_vm_prot_bits() macro uses VM_PKEY_BIT0 etc. which are
not part of the UAPI, so the macro is completely useless for userspac

x86: Remove the arch_calc_vm_prot_bits() macro from the UAPI

The arch_calc_vm_prot_bits() macro uses VM_PKEY_BIT0 etc. which are
not part of the UAPI, so the macro is completely useless for userspace.

It is also hidden behind the CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
config switch which we shouldn't expose to userspace. Thus let's move
this macro into a new internal header instead.

Fixes: 8f62c883222c ("x86/mm/pkeys: Add arch-specific VMA protection bits")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lore.kernel.org/r/20230906162658.142511-1-thuth@redhat.com

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Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 shadow stack support from Dave Hansen:
"This is the long awaited x86 shadow stack support, part o

Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 shadow stack support from Dave Hansen:
"This is the long awaited x86 shadow stack support, part of Intel's
Control-flow Enforcement Technology (CET).

CET consists of two related security features: shadow stacks and
indirect branch tracking. This series implements just the shadow stack
part of this feature, and just for userspace.

The main use case for shadow stack is providing protection against
return oriented programming attacks. It works by maintaining a
secondary (shadow) stack using a special memory type that has
protections against modification. When executing a CALL instruction,
the processor pushes the return address to both the normal stack and
to the special permission shadow stack. Upon RET, the processor pops
the shadow stack copy and compares it to the normal stack copy.

For more information, refer to the links below for the earlier
versions of this patch set"

Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/
Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/

* tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
x86/shstk: Change order of __user in type
x86/ibt: Convert IBT selftest to asm
x86/shstk: Don't retry vm_munmap() on -EINTR
x86/kbuild: Fix Documentation/ reference
x86/shstk: Move arch detail comment out of core mm
x86/shstk: Add ARCH_SHSTK_STATUS
x86/shstk: Add ARCH_SHSTK_UNLOCK
x86: Add PTRACE interface for shadow stack
selftests/x86: Add shadow stack test
x86/cpufeatures: Enable CET CR4 bit for shadow stack
x86/shstk: Wire in shadow stack interface
x86: Expose thread features in /proc/$PID/status
x86/shstk: Support WRSS for userspace
x86/shstk: Introduce map_shadow_stack syscall
x86/shstk: Check that signal frame is shadow stack mem
x86/shstk: Check that SSP is aligned on sigreturn
x86/shstk: Handle signals for shadow stack
x86/shstk: Introduce routines modifying shstk
x86/shstk: Handle thread shadow stack
x86/shstk: Add user-mode shadow stack support
...

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x86/shstk: Introduce map_shadow_stack syscall

When operating with shadow stacks enabled, the kernel will automatically
allocate shadow stacks for new threads, however in some cases userspace
will ne

x86/shstk: Introduce map_shadow_stack syscall

When operating with shadow stacks enabled, the kernel will automatically
allocate shadow stacks for new threads, however in some cases userspace
will need additional shadow stacks. The main example of this is the
ucontext family of functions, which require userspace allocating and
pivoting to userspace managed stacks.

Unlike most other user memory permissions, shadow stacks need to be
provisioned with special data in order to be useful. They need to be setup
with a restore token so that userspace can pivot to them via the RSTORSSP
instruction. But, the security design of shadow stacks is that they
should not be written to except in limited circumstances. This presents a
problem for userspace, as to how userspace can provision this special
data, without allowing for the shadow stack to be generally writable.

Previously, a new PROT_SHADOW_STACK was attempted, which could be
mprotect()ed from RW permissions after the data was provisioned. This was
found to not be secure enough, as other threads could write to the
shadow stack during the writable window.

The kernel can use a special instruction, WRUSS, to write directly to
userspace shadow stacks. So the solution can be that memory can be mapped
as shadow stack permissions from the beginning (never generally writable
in userspace), and the kernel itself can write the restore token.

First, a new madvise() flag was explored, which could operate on the
PROT_SHADOW_STACK memory. This had a couple of downsides:
1. Extra checks were needed in mprotect() to prevent writable memory from
ever becoming PROT_SHADOW_STACK.
2. Extra checks/vma state were needed in the new madvise() to prevent
restore tokens being written into the middle of pre-used shadow stacks.
It is ideal to prevent restore tokens being added at arbitrary
locations, so the check was to make sure the shadow stack had never been
written to.
3. It stood out from the rest of the madvise flags, as more of direct
action than a hint at future desired behavior.

So rather than repurpose two existing syscalls (mmap, madvise) that don't
quite fit, just implement a new map_shadow_stack syscall to allow
userspace to map and setup new shadow stacks in one step. While ucontext
is the primary motivator, userspace may have other unforeseen reasons to
setup its own shadow stacks using the WRSS instruction. Towards this
provide a flag so that stacks can be optionally setup securely for the
common case of ucontext without enabling WRSS. Or potentially have the
kernel set up the shadow stack in some new way.

The following example demonstrates how to create a new shadow stack with
map_shadow_stack:
void *shstk = map_shadow_stack(addr, stack_size, SHADOW_STACK_SET_TOKEN);

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-35-rick.p.edgecombe%40intel.com

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x86/mm: Introduce MAP_ABOVE4G

The x86 Control-flow Enforcement Technology (CET) feature includes a new
type of memory called shadow stack. This shadow stack memory has some
unusual properties, which

x86/mm: Introduce MAP_ABOVE4G

The x86 Control-flow Enforcement Technology (CET) feature includes a new
type of memory called shadow stack. This shadow stack memory has some
unusual properties, which require some core mm changes to function
properly.

One of the properties is that the shadow stack pointer (SSP), which is a
CPU register that points to the shadow stack like the stack pointer points
to the stack, can't be pointing outside of the 32 bit address space when
the CPU is executing in 32 bit mode. It is desirable to prevent executing
in 32 bit mode when shadow stack is enabled because the kernel can't easily
support 32 bit signals.

On x86 it is possible to transition to 32 bit mode without any special
interaction with the kernel, by doing a "far call" to a 32 bit segment.
So the shadow stack implementation can use this address space behavior
as a feature, by enforcing that shadow stack memory is always mapped
outside of the 32 bit address space. This way userspace will trigger a
general protection fault which will in turn trigger a segfault if it
tries to transition to 32 bit mode with shadow stack enabled.

This provides a clean error generating border for the user if they try
attempt to do 32 bit mode shadow stack, rather than leave the kernel in a
half working state for userspace to be surprised by.

So to allow future shadow stack enabling patches to map shadow stacks
out of the 32 bit address space, introduce MAP_ABOVE4G. The behavior
is pretty much like MAP_32BIT, except that it has the opposite address
range. The are a few differences though.

If both MAP_32BIT and MAP_ABOVE4G are provided, the kernel will use the
MAP_ABOVE4G behavior. Like MAP_32BIT, MAP_ABOVE4G is ignored in a 32 bit
syscall.

Since the default search behavior is top down, the normal kaslr base can
be used for MAP_ABOVE4G. This is unlike MAP_32BIT which has to add its
own randomization in the bottom up case.

For MAP_32BIT, only the bottom up search path is used. For MAP_ABOVE4G
both are potentially valid, so both are used. In the bottomup search
path, the default behavior is already consistent with MAP_ABOVE4G since
mmap base should be above 4GB.

Without MAP_ABOVE4G, the shadow stack will already normally be above 4GB.
So without introducing MAP_ABOVE4G, trying to transition to 32 bit mode
with shadow stack enabled would usually segfault anyway. This is already
pretty decent guard rails. But the addition of MAP_ABOVE4G is some small
complexity spent to make it make it more complete.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-21-rick.p.edgecombe%40intel.com

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Merge branch 'main' into zstd-linus

Merge branch 'main' into zstd-next

Merge drm/drm-next into drm-intel-gt-next

Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match
callback functions") in order to merge the DG2 HuC patches.

Signed-off-by: Tvrtko

Merge drm/drm-next into drm-intel-gt-next

Daniele needs 84d4333c1e28 ("misc/mei: Add NULL check to component match
callback functions") in order to merge the DG2 HuC patches.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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Merge part of branch 'for-next.instantiate' into for-next

Merge drm/drm-next into drm-intel-next

Sync up. In special to get the drm-intel-gt-next stuff.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge branch 'next' into for-linus

Prepare input updates for 5.20 (or 6.0) merge window.

Merge drm/drm-next into drm-misc-next-fixes

Backmerging from drm/drm-next for the final fixes that will go
into v5.20.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'v5.19-rc5' into next

Merge with mainline to bring up the latest definition from MFD subsystem
needed for Mediatek keypad driver.