It is safer and simpler to drop the uaccess assembly macros in favour of
inline C functions. Although this bloats the Image size slightly, it
aligns our user copy routines with '{get,put}_user()' and generally
makes the code a lot easier to reason about.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
[will: tweaked commit message and changed temporary variable names]
Signed-off-by: Will Deacon <will@kernel.org>
A number of our uaccess routines ('__arch_clear_user()' and
'__arch_copy_{in,from,to}_user()') fail to re-enable PAN if they
encounter an unhandled fault whilst accessing userspace.
For CPUs implementing both hardware PAN and UAO, this bug has no effect
when both extensions are in use by the kernel.
For CPUs implementing hardware PAN but not UAO, this means that a kernel
using hardware PAN may execute portions of code with PAN inadvertently
disabled, opening us up to potential security vulnerabilities that rely
on userspace access from within the kernel which would usually be
prevented by this mechanism. In other words, parts of the kernel run the
same way as they would on a CPU without PAN implemented/emulated at all.
For CPUs not implementing hardware PAN and instead relying on software
emulation via 'CONFIG_ARM64_SW_TTBR0_PAN=y', the impact is unfortunately
much worse. Calling 'schedule()' with software PAN disabled means that
the next task will execute in the kernel using the page-table and ASID
of the previous process even after 'switch_mm()', since the actual
hardware switch is deferred until return to userspace. At this point, or
if there is a intermediate call to 'uaccess_enable()', the page-table
and ASID of the new process are installed. Sadly, due to the changes
introduced by KPTI, this is not an atomic operation and there is a very
small window (two instructions) where the CPU is configured with the
page-table of the old task and the ASID of the new task; a speculative
access in this state is disastrous because it would corrupt the TLB
entries for the new task with mappings from the previous address space.
As Pavel explains:
| I was able to reproduce memory corruption problem on Broadcom's SoC
| ARMv8-A like this:
|
| Enable software perf-events with PERF_SAMPLE_CALLCHAIN so userland's
| stack is accessed and copied.
|
| The test program performed the following on every CPU and forking
| many processes:
|
| unsigned long *map = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE,
| MAP_SHARED | MAP_ANONYMOUS, -1, 0);
| map[0] = getpid();
| sched_yield();
| if (map[0] != getpid()) {
| fprintf(stderr, "Corruption detected!");
| }
| munmap(map, PAGE_SIZE);
|
| From time to time I was getting map[0] to contain pid for a
| different process.
Ensure that PAN is re-enabled when returning after an unhandled user
fault from our uaccess routines.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Fixes: 338d4f49d6 ("arm64: kernel: Add support for Privileged Access Never")
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
[will: rewrote commit message]
Signed-off-by: Will Deacon <will@kernel.org>
When the CC variable contains quotes, e.g. when using
ccache (make CC="ccache <compiler>"), this script always
fails, so CONFIG_RELR is never enabled, even when the
toolchain supports this feature. Removing the /dev/null
redirect and invoking the script manually shows the issue:
$ CC='/usr/bin/ccache clang' ./scripts/tools-support-relr.sh
./scripts/tools-support-relr.sh: 7: ./scripts/tools-support-relr.sh: /usr/bin/ccache clang: not found
Fix this by un-quoting the variables.
Before:
$ make ARCH=arm64 CC='/usr/bin/ccache clang' LD=ld.lld \
NM=llvm-nm OBJCOPY=llvm-objcopy defconfig
$ grep RELR .config
CONFIG_ARCH_HAS_RELR=y
With this change:
$ make ARCH=arm64 CC='/usr/bin/ccache clang' LD=ld.lld \
NM=llvm-nm OBJCOPY=llvm-objcopy defconfig
$ grep RELR .config
CONFIG_TOOLS_SUPPORT_RELR=y
CONFIG_ARCH_HAS_RELR=y
CONFIG_RELR=y
Fixes: 5cf896fb6b ("arm64: Add support for relocating the kernel with RELR relocations")
Reported-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/769
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Following commit 73e86cb03c ("arm64: Move PTE_RDONLY bit handling out
of set_pte_at()"), the PTE_RDONLY bit is no longer managed by
set_pte_at() but built into the PAGE_* attribute definitions.
Consequently, pte_same() must include this bit when checking two PTEs
for equality.
Remove the arm64-specific pte_same() function, practically reverting
commit 747a70e60b ("arm64: Fix copy-on-write referencing in HugeTLB")
Fixes: 73e86cb03c ("arm64: Move PTE_RDONLY bit handling out of set_pte_at()")
Cc: <stable@vger.kernel.org> # 4.14.x-
Cc: Will Deacon <will@kernel.org>
Cc: Steve Capper <steve.capper@arm.com>
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
The Broadcom Brahma-B53 core is susceptible to the issue described by
ARM64_ERRATUM_843419 so this commit enables the workaround to be applied
when executing on that core.
Since there are now multiple entries to match, we must convert the
existing ARM64_ERRATUM_843419 into an erratum list and use
cpucap_multi_entry_cap_matches to match our entries.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
Add the Brahma-B53 CPU (all versions) to the whitelists of CPUs for the
SSB and spectre v2 mitigations.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
The Broadcom Brahma-B53 core is susceptible to the issue described by
ARM64_ERRATUM_845719 so this commit enables the workaround to be applied
when executing on that core.
Since there are now multiple entries to match, we must convert the
existing ARM64_ERRATUM_845719 into an erratum list.
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
The Kryo cores share errata 1009 with Falkor, so add their model
definitions and enable it for them as well.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[will: Update entry in silicon-errata.rst]
Signed-off-by: Will Deacon <will@kernel.org>
With the introduction of 'cce360b54ce6 ("arm64: capabilities: Filter the
entries based on a given mask")' the Qualcomm Falkor/Kryo errata 1003 is
no long applied.
The result of not applying errata 1003 is that MSM8996 runs into various
RCU stalls and fails to boot most of the times.
Give 1003 a "type" to ensure they are not filtered out in
update_cpu_capabilities().
Fixes: cce360b54c ("arm64: capabilities: Filter the entries based on a given mask")
Cc: stable@vger.kernel.org
Reported-by: Mark Brown <broonie@kernel.org>
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Shared and writable mappings (__S.1.) should be clean (!dirty) initially
and made dirty on a subsequent write either through the hardware DBM
(dirty bit management) mechanism or through a write page fault. A clean
pte for the arm64 kernel is one that has PTE_RDONLY set and PTE_DIRTY
clear.
The PAGE_SHARED{,_EXEC} attributes have PTE_WRITE set (PTE_DBM) and
PTE_DIRTY clear. Prior to commit 73e86cb03c ("arm64: Move PTE_RDONLY
bit handling out of set_pte_at()"), it was the responsibility of
set_pte_at() to set the PTE_RDONLY bit and mark the pte clean if the
software PTE_DIRTY bit was not set. However, the above commit removed
the pte_sw_dirty() check and the subsequent setting of PTE_RDONLY in
set_pte_at() while leaving the PAGE_SHARED{,_EXEC} definitions
unchanged. The result is that shared+writable mappings are now dirty by
default
Fix the above by explicitly setting PTE_RDONLY in PAGE_SHARED{,_EXEC}.
In addition, remove the superfluous PTE_DIRTY bit from the kernel PROT_*
attributes.
Fixes: 73e86cb03c ("arm64: Move PTE_RDONLY bit handling out of set_pte_at()")
Cc: <stable@vger.kernel.org> # 4.14.x-
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Workaround for Cavium/Marvell ThunderX2 erratum #219.
* errata/tx2-219:
arm64: Allow CAVIUM_TX2_ERRATUM_219 to be selected
arm64: Avoid Cavium TX2 erratum 219 when switching TTBR
arm64: Enable workaround for Cavium TX2 erratum 219 when running SMT
arm64: KVM: Trap VM ops when ARM64_WORKAROUND_CAVIUM_TX2_219_TVM is set
Sign-extending TTBR1 addresses when converting to an untagged address
breaks the documented POSIX semantics for mlock() in some obscure error
cases where we end up returning -EINVAL instead of -ENOMEM as a direct
result of rewriting the upper address bits.
Rework the untagged_addr() macro to preserve the upper address bits for
TTBR1 addresses and only clear the tag bits for user addresses. This
matches the behaviour of the 'clear_address_tag' assembly macro, so
rename that and align the implementations at the same time so that they
use the same instruction sequences for the tag manipulation.
Link: https://lore.kernel.org/stable/20191014162651.GF19200@arrakis.emea.arm.com/
Reported-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
When detecting a spurious EL1 translation fault, we have the CPU retry
the translation using an AT S1E1R instruction, and inspect PAR_EL1 to
determine if the fault was spurious.
When PAR_EL1.F == 0, the AT instruction successfully translated the
address without a fault, which implies the original fault was spurious.
However, in this case we return false and treat the original fault as if
it was not spurious.
Invert the return value so that we treat such a case as spurious.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 42f91093b0 ("arm64: mm: Ignore spurious translation faults taken from the kernel")
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
The 'F' field of the PAR_EL1 register lives in bit 0, not bit 1.
Fix the broken definition in 'sysreg.h'.
Fixes: e8620cff99 ("arm64: sysreg: Add some field definitions for PAR_EL1")
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
Preempting from IRQ-return means that the task has its PSTATE saved
on the stack, which will get restored when the task is resumed and does
the actual IRQ return.
However, enabling some CPU features requires modifying the PSTATE. This
means that, if a task was scheduled out during an IRQ-return before all
CPU features are enabled, the task might restore a PSTATE that does not
include the feature enablement changes once scheduled back in.
* Task 1:
PAN == 0 ---| |---------------
| |<- return from IRQ, PSTATE.PAN = 0
| <- IRQ |
+--------+ <- preempt() +--
^
|
reschedule Task 1, PSTATE.PAN == 1
* Init:
--------------------+------------------------
^
|
enable_cpu_features
set PSTATE.PAN on all CPUs
Worse than this, since PSTATE is untouched when task switching is done,
a task missing the new bits in PSTATE might affect another task, if both
do direct calls to schedule() (outside of IRQ/exception contexts).
Fix this by preventing preemption on IRQ-return until features are
enabled on all CPUs.
This way the only PSTATE values that are saved on the stack are from
synchronous exceptions. These are expected to be fatal this early, the
exception is BRK for WARN_ON(), but as this uses do_debug_exception()
which keeps IRQs masked, it shouldn't call schedule().
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
[james: Replaced a really cool hack, with an even simpler static key in C.
expanded commit message with Julien's cover-letter ascii art]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
There is a bug in create_safe_exec_page(), when page table is allocated
it is not checked that table is allocated successfully:
But it is dereferenced in: pgd_none(READ_ONCE(*pgdp)). Check that
allocation was successful.
Fixes: 82869ac57b ("arm64: kernel: Add support for hibernate/suspend-to-disk")
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Will Deacon <will@kernel.org>
If CONFIG_ARM64_SVE=n then we fail to report ID_AA64ZFR0_EL1 as 0 when
read by userspace, despite being required by the architecture. Although
this is theoretically a change in ABI, userspace will first check for
the presence of SVE via the HWCAP or the ID_AA64PFR0_EL1.SVE field
before probing the ID_AA64ZFR0_EL1 register. Given that these are
reported correctly for this configuration, we can safely tighten up the
current behaviour.
Ensure ID_AA64ZFR0_EL1 is treated as RAZ when CONFIG_ARM64_SVE=n.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Fixes: 06a916feca ("arm64: Expose SVE2 features for userspace")
Signed-off-by: Will Deacon <will@kernel.org>
We export the entire kernel address space (i.e. the whole of the TTBR1
address range) via /proc/kcore. The kc_vaddr_to_offset() and
kc_offset_to_vaddr() macros are intended to convert between a kernel
virtual address and its offset relative to the start of the TTBR1
address space.
Prior to commit:
14c127c957 ("arm64: mm: Flip kernel VA space")
... the offset was calculated relative to VA_START, which at the time
was the start of the TTBR1 address space. At this time, PAGE_OFFSET
pointed to the high half of the TTBR1 address space where arm64's
linear map lived.
That commit swapped the position of VA_START and PAGE_OFFSET, but
failed to update kc_vaddr_to_offset() or kc_offset_to_vaddr(), so
since then the two macros behave incorrectly.
Note that VA_START was subsequently renamed to PAGE_END in commit:
77ad4ce693 ("arm64: memory: rename VA_START to PAGE_END")
As the generic implementations of the two macros calculate the offset
relative to PAGE_OFFSET (which is now the start of the TTBR1 address
space), we can delete the arm64 implementation and use those.
Fixes: 14c127c957 ("arm64: mm: Flip kernel VA space")
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
There are no return value checking when using kzalloc() and kcalloc() for
memory allocation. so add it.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
Allow the user to select the workaround for TX2-219, and update
the silicon-errata.rst file to reflect this.
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
As a PRFM instruction racing against a TTBR update can have undesirable
effects on TX2, NOP-out such PRFM on cores that are affected by
the TX2-219 erratum.
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
It appears that the only case where we need to apply the TX2_219_TVM
mitigation is when the core is in SMT mode. So let's condition the
enabling on detecting a CPU whose MPIDR_EL1.Aff0 is non-zero.
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
In order to workaround the TX2-219 erratum, it is necessary to trap
TTBRx_EL1 accesses to EL2. This is done by setting HCR_EL2.TVM on
guest entry, which has the side effect of trapping all the other
VM-related sysregs as well.
To minimize the overhead, a fast path is used so that we don't
have to go all the way back to the main sysreg handling code,
unless the rest of the hypervisor expects to see these accesses.
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
CONFIG_COMPAT_VDSO is defined by passing '-DCONFIG_COMPAT_VDSO' to the
compiler when the generic compat vDSO code is in use. It's much cleaner
and simpler to expose this as a proper Kconfig option (like x86 does),
so do that and remove the bodge.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
For consistency with CROSS_COMPILE_COMPAT, mechanically rename COMPATCC
to CC_COMPAT so that specifying aspects of the compat vDSO toolchain in
the environment isn't needlessly confusing.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Directly passing the '--target' option to clang by appending to
COMPATCC does not work if COMPATCC has been specified explicitly as
an argument to Make unless the 'override' directive is used, which is
ugly and different to what is done in the top-level Makefile.
Move the '--target' option for clang out of COMPATCC and into
VDSO_CAFLAGS, where it will be picked up when compiling and assembling
the 32-bit vDSO under clang.
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
KBUILD_CPPFLAGS is defined differently depending on whether the main
compiler is clang or not. This means that it is not possible to build
the compat vDSO with GCC if the rest of the kernel is built with clang.
Define VDSO_CPPFLAGS directly to break this dependency and allow a clang
kernel to build a compat vDSO with GCC:
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
CROSS_COMPILE_COMPAT=arm-linux-gnueabihf- CC=clang \
COMPATCC=arm-linux-gnueabihf-gcc
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
There's no need to export COMPATCC, so just define it locally in the
vdso32/Makefile, which is the only place where it is used.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Rather than force the use of GCC for the compat cross-compiler, instead
extract the target from CROSS_COMPILE_COMPAT and pass it to clang if the
main compiler is clang.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
arm64 was the last architecture using CROSS_COMPILE_COMPAT_VDSO config
option. With this patch series the dependency in the architecture has
been removed.
Remove CROSS_COMPILE_COMPAT_VDSO from the Unified vDSO library code.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
The jump labels are not used in vdso32 since it is not possible to run
runtime patching on them.
Remove the configuration option from the Makefile.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Older versions of binutils (prior to 2.24) do not support the "ISHLD"
option for memory barrier instructions, which leads to a build failure
when assembling the vdso32 library.
Add a compilation time mechanism that detects if binutils supports those
instructions and configure the kernel accordingly.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Moving over to the generic C implementation of the vDSO inadvertently
left some stale files behind which are no longer used. Remove them.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
The .config file and the generated include/config/auto.conf can
end up out of sync after a set of commands since
CONFIG_CROSS_COMPILE_COMPAT_VDSO is not updated correctly.
The sequence can be reproduced as follows:
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
[...]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig
[set CONFIG_CROSS_COMPILE_COMPAT_VDSO="arm-linux-gnueabihf-"]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-
Which results in:
arch/arm64/Makefile:62: CROSS_COMPILE_COMPAT not defined or empty,
the compat vDSO will not be built
even though the compat vDSO has been built:
$ file arch/arm64/kernel/vdso32/vdso.so
arch/arm64/kernel/vdso32/vdso.so: ELF 32-bit LSB pie executable, ARM,
EABI5 version 1 (SYSV), dynamically linked,
BuildID[sha1]=c67f6c786f2d2d6f86c71f708595594aa25247f6, stripped
A similar case that involves changing the configuration parameter
multiple times can be reconducted to the same family of problems.
Remove the use of CONFIG_CROSS_COMPILE_COMPAT_VDSO altogether and
instead rely on the cross-compiler prefix coming from the environment
via CROSS_COMPILE_COMPAT, much like we do for the rest of the kernel.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
When detecting a spurious EL1 translation fault, we attempt to compare
ESR_EL1.DFSC with PAR_EL1.FST. We erroneously use FIELD_PREP() to
extract PAR_EL1.FST, when we should be using FIELD_GET().
In the wise words of Robin Murphy:
| FIELD_GET() is a UBFX, FIELD_PREP() is a BFI
Using FIELD_PREP() means that that dfsc & ESR_ELx_FSC_TYPE is always
zero, and hence not equal to ESR_ELx_FSC_FAULT. Thus we detect any
unhandled translation fault as spurious.
... so let's use FIELD_GET() to ensure we don't decide all translation
faults are spurious. ESR_EL1.DFSC occupies bits [5:0], and requires no
shifting.
Fixes: 42f91093b0 ("arm64: mm: Ignore spurious translation faults taken from the kernel")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Robin Murphy <robin.murphy@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
In commit 4ed2863951 ("fs, elf: drop MAP_FIXED usage from elf_map") we
changed elf to use MAP_FIXED_NOREPLACE instead of MAP_FIXED for the
executable mappings.
Then, people reported that it broke some binaries that had overlapping
segments from the same file, and commit ad55eac74f ("elf: enforce
MAP_FIXED on overlaying elf segments") re-instated MAP_FIXED for some
overlaying elf segment cases. But only some - despite the summary line
of that commit, it only did it when it also does a temporary brk vma for
one obvious overlapping case.
Now Russell King reports another overlapping case with old 32-bit x86
binaries, which doesn't trigger that limited case. End result: we had
better just drop MAP_FIXED_NOREPLACE entirely, and go back to MAP_FIXED.
Yes, it's a sign of old binaries generated with old tool-chains, but we
do pride ourselves on not breaking existing setups.
This still leaves MAP_FIXED_NOREPLACE in place for the load_elf_interp()
and the old load_elf_library() use-cases, because nobody has reported
breakage for those. Yet.
Note that in all the cases seen so far, the overlapping elf sections
seem to be just re-mapping of the same executable with different section
attributes. We could possibly introduce a new MAP_FIXED_NOFILECHANGE
flag or similar, which acts like NOREPLACE, but allows just remapping
the same executable file using different protection flags.
It's not clear that would make a huge difference to anything, but if
people really hate that "elf remaps over previous maps" behavior, maybe
at least a more limited form of remapping would alleviate some concerns.
Alternatively, we should take a look at our elf_map() logic to see if we
end up not mapping things properly the first time.
In the meantime, this is the minimal "don't do that then" patch while
people hopefully think about it more.
Reported-by: Russell King <linux@armlinux.org.uk>
Fixes: 4ed2863951 ("fs, elf: drop MAP_FIXED usage from elf_map")
Fixes: ad55eac74f ("elf: enforce MAP_FIXED on overlaying elf segments")
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- revert an incorret hunk from a patch that caused problems
on various arm boards (Andrey Smirnov)
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Merge tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping regression fix from Christoph Hellwig:
"Revert an incorret hunk from a patch that caused problems on various
arm boards (Andrey Smirnov)"
* tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix false positive warnings in dma_common_free_remap()
A few fixes this time around:
- Fixup of some clock specifications for DRA7 (device-tree fix)
- Removal of some dead/legacy CPU OPP/PM code for OMAP that throws
warnings at boot
- A few more minor fixups for OMAPs, most around display
- Enable STM32 QSPI as =y since their rootfs sometimes comes from
there
- Switch CONFIG_REMOTEPROC to =y since it went from tristate to bool
- Fix of thermal zone definition for ux500 (5.4 regression)
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Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC fixes from Olof Johansson:
"A few fixes this time around:
- Fixup of some clock specifications for DRA7 (device-tree fix)
- Removal of some dead/legacy CPU OPP/PM code for OMAP that throws
warnings at boot
- A few more minor fixups for OMAPs, most around display
- Enable STM32 QSPI as =y since their rootfs sometimes comes from
there
- Switch CONFIG_REMOTEPROC to =y since it went from tristate to bool
- Fix of thermal zone definition for ux500 (5.4 regression)"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: multi_v7_defconfig: Fix SPI_STM32_QSPI support
ARM: dts: ux500: Fix up the CPU thermal zone
arm64/ARM: configs: Change CONFIG_REMOTEPROC from m to y
ARM: dts: am4372: Set memory bandwidth limit for DISPC
ARM: OMAP2+: Fix warnings with broken omap2_set_init_voltage()
ARM: OMAP2+: Add missing LCDC midlemode for am335x
ARM: OMAP2+: Fix missing reset done flag for am3 and am43
ARM: dts: Fix gpio0 flags for am335x-icev2
ARM: omap2plus_defconfig: Enable more droid4 devices as loadable modules
ARM: omap2plus_defconfig: Enable DRM_TI_TFP410
DTS: ARM: gta04: introduce legacy spi-cs-high to make display work again
ARM: dts: Fix wrong clocks for dra7 mcasp
clk: ti: dra7: Fix mcasp8 clock bits
- remove unneeded ar-option and KBUILD_ARFLAGS
- remove long-deprecated SUBDIRS
- fix modpost to suppress false-positive warnings for UML builds
- fix namespace.pl to handle relative paths to ${objtree}, ${srctree}
- make setlocalversion work for /bin/sh
- make header archive reproducible
- fix some Makefiles and documents
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Merge tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- remove unneeded ar-option and KBUILD_ARFLAGS
- remove long-deprecated SUBDIRS
- fix modpost to suppress false-positive warnings for UML builds
- fix namespace.pl to handle relative paths to ${objtree}, ${srctree}
- make setlocalversion work for /bin/sh
- make header archive reproducible
- fix some Makefiles and documents
* tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: make headers archive reproducible
kbuild: update compile-test header list for v5.4-rc2
kbuild: two minor updates for Documentation/kbuild/modules.rst
scripts/setlocalversion: clear local variable to make it work for sh
namespace: fix namespace.pl script to support relative paths
video/logo: do not generate unneeded logo C files
video/logo: remove unneeded *.o pattern from clean-files
integrity: remove pointless subdir-$(CONFIG_...)
integrity: remove unneeded, broken attempt to add -fshort-wchar
modpost: fix static EXPORT_SYMBOL warnings for UML build
kbuild: correct formatting of header in kbuild module docs
kbuild: remove SUBDIRS support
kbuild: remove ar-option and KBUILD_ARFLAGS
Twelve patches mostly small but obvious fixes or cosmetic but small
updates.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Twelve patches mostly small but obvious fixes or cosmetic but small
updates"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: qla2xxx: Fix Nport ID display value
scsi: qla2xxx: Fix N2N link up fail
scsi: qla2xxx: Fix N2N link reset
scsi: qla2xxx: Optimize NPIV tear down process
scsi: qla2xxx: Fix stale mem access on driver unload
scsi: qla2xxx: Fix unbound sleep in fcport delete path.
scsi: qla2xxx: Silence fwdump template message
scsi: hisi_sas: Make three functions static
scsi: megaraid: disable device when probe failed after enabled device
scsi: storvsc: setup 1:1 mapping between hardware queue and CPU queue
scsi: qedf: Remove always false 'tmp_prio < 0' statement
scsi: ufs: skip shutdown if hba is not powered
scsi: bnx2fc: Handle scope bits when array returns BUSY or TSF
This makes getdents() and getdents64() do sanity checking on the
pathname that it gives to user space. And to mitigate the performance
impact of that, it first cleans up the way it does the user copying, so
that the code avoids doing the SMAP/PAN updates between each part of the
dirent structure write.
I really wanted to do this during the merge window, but didn't have
time. The conversion of filldir to unsafe_put_user() is something I've
had around for years now in a private branch, but the extra pathname
checking finally made me clean it up to the point where it is mergable.
It's worth noting that the filename validity checking really should be a
bit smarter: it would be much better to delay the error reporting until
the end of the readdir, so that non-corrupted filenames are still
returned. But that involves bigger changes, so let's see if anybody
actually hits the corrupt directory entry case before worrying about it
further.
* branch 'readdir':
Make filldir[64]() verify the directory entry filename is valid
Convert filldir[64]() from __put_user() to unsafe_put_user()
This has been discussed several times, and now filesystem people are
talking about doing it individually at the filesystem layer, so head
that off at the pass and just do it in getdents{64}().
This is partially based on a patch by Jann Horn, but checks for NUL
bytes as well, and somewhat simplified.
There's also commentary about how it might be better if invalid names
due to filesystem corruption don't cause an immediate failure, but only
an error at the end of the readdir(), so that people can still see the
filenames that are ok.
There's also been discussion about just how much POSIX strictly speaking
requires this since it's about filesystem corruption. It's really more
"protect user space from bad behavior" as pointed out by Jann. But
since Eric Biederman looked up the POSIX wording, here it is for context:
"From readdir:
The readdir() function shall return a pointer to a structure
representing the directory entry at the current position in the
directory stream specified by the argument dirp, and position the
directory stream at the next entry. It shall return a null pointer
upon reaching the end of the directory stream. The structure dirent
defined in the <dirent.h> header describes a directory entry.
From definitions:
3.129 Directory Entry (or Link)
An object that associates a filename with a file. Several directory
entries can associate names with the same file.
...
3.169 Filename
A name consisting of 1 to {NAME_MAX} bytes used to name a file. The
characters composing the name may be selected from the set of all
character values excluding the slash character and the null byte. The
filenames dot and dot-dot have special meaning. A filename is
sometimes referred to as a 'pathname component'."
Note that I didn't bother adding the checks to any legacy interfaces
that nobody uses.
Also note that if this ends up being noticeable as a performance
regression, we can fix that to do a much more optimized model that
checks for both NUL and '/' at the same time one word at a time.
We haven't really tended to optimize 'memchr()', and it only checks for
one pattern at a time anyway, and we really _should_ check for NUL too
(but see the comment about "soft errors" in the code about why it
currently only checks for '/')
See the CONFIG_DCACHE_WORD_ACCESS case of hash_name() for how the name
lookup code looks for pathname terminating characters in parallel.
Link: https://lore.kernel.org/lkml/20190118161440.220134-2-jannh@google.com/
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We really should avoid the "__{get,put}_user()" functions entirely,
because they can easily be mis-used and the original intent of being
used for simple direct user accesses no longer holds in a post-SMAP/PAN
world.
Manually optimizing away the user access range check makes no sense any
more, when the range check is generally much cheaper than the "enable
user accesses" code that the __{get,put}_user() functions still need.
So instead of __put_user(), use the unsafe_put_user() interface with
user_access_{begin,end}() that really does generate better code these
days, and which is generally a nicer interface. Under some loads, the
multiple user writes that filldir() does are actually quite noticeable.
This also makes the dirent name copy use unsafe_put_user() with a couple
of macros. We do not want to make function calls with SMAP/PAN
disabled, and the code this generates is quite good when the
architecture uses "asm goto" for unsafe_put_user() like x86 does.
Note that this doesn't bother with the legacy cases. Nobody should use
them anyway, so performance doesn't really matter there.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking fixes from David Miller:
1) Fix ieeeu02154 atusb driver use-after-free, from Johan Hovold.
2) Need to validate TCA_CBQ_WRROPT netlink attributes, from Eric
Dumazet.
3) txq null deref in mac80211, from Miaoqing Pan.
4) ionic driver needs to select NET_DEVLINK, from Arnd Bergmann.
5) Need to disable bh during nft_connlimit GC, from Pablo Neira Ayuso.
6) Avoid division by zero in taprio scheduler, from Vladimir Oltean.
7) Various xgmac fixes in stmmac driver from Jose Abreu.
8) Avoid 64-bit division in mlx5 leading to link errors on 32-bit from
Michal Kubecek.
9) Fix bad VLAN check in rtl8366 DSA driver, from Linus Walleij.
10) Fix sleep while atomic in sja1105, from Vladimir Oltean.
11) Suspend/resume deadlock in stmmac, from Thierry Reding.
12) Various UDP GSO fixes from Josh Hunt.
13) Fix slab out of bounds access in tcp_zerocopy_receive(), from Eric
Dumazet.
14) Fix OOPS in __ipv6_ifa_notify(), from David Ahern.
15) Memory leak in NFC's llcp_sock_bind, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (72 commits)
selftests/net: add nettest to .gitignore
net: qlogic: Fix memory leak in ql_alloc_large_buffers
nfc: fix memory leak in llcp_sock_bind()
sch_dsmark: fix potential NULL deref in dsmark_init()
net: phy: at803x: use operating parameters from PHY-specific status
net: phy: extract pause mode
net: phy: extract link partner advertisement reading
net: phy: fix write to mii-ctrl1000 register
ipv6: Handle missing host route in __ipv6_ifa_notify
net: phy: allow for reset line to be tied to a sleepy GPIO controller
net: ipv4: avoid mixed n_redirects and rate_tokens usage
r8152: Set macpassthru in reset_resume callback
cxgb4:Fix out-of-bounds MSI-X info array access
Revert "ipv6: Handle race in addrconf_dad_work"
net: make sock_prot_memory_pressure() return "const char *"
rxrpc: Fix rxrpc_recvmsg tracepoint
qmi_wwan: add support for Cinterion CLS8 devices
tcp: fix slab-out-of-bounds in tcp_zerocopy_receive()
lib: textsearch: fix escapes in example code
udp: only do GSO if # of segs > 1
...
- Default configs updates.
- Fix build errors with CC_OPTIMIZE_FOR_SIZE due to usage of "i" constraint
for function arguments. Two kvm changes acked-by Christian Borntraeger.
- Fix -Wunused-but-set-variable warnings in mm code.
- Avoid a constant misuse in qdio.
- Handle a case when cpumf is temporarily unavailable.
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Merge tag 's390-5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik:
- defconfig updates
- Fix build errors with CC_OPTIMIZE_FOR_SIZE due to usage of "i"
constraint for function arguments. Two kvm changes acked-by Christian
Borntraeger.
- Fix -Wunused-but-set-variable warnings in mm code.
- Avoid a constant misuse in qdio.
- Handle a case when cpumf is temporarily unavailable.
* tag 's390-5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
KVM: s390: mark __insn32_query() as __always_inline
KVM: s390: fix __insn32_query() inline assembly
s390: update defconfigs
s390/pci: mark function(s) __always_inline
s390/mm: mark function(s) __always_inline
s390/jump_label: mark function(s) __always_inline
s390/cpu_mf: mark function(s) __always_inline
s390/atomic,bitops: mark function(s) __always_inline
s390/mm: fix -Wunused-but-set-variable warnings
s390: mark __cpacf_query() as __always_inline
s390/qdio: clarify size of the QIB parm area
s390/cpumf: Fix indentation in sampling device driver
s390/cpumsf: Check for CPU Measurement sampling
s390/cpumf: Use consistant debug print format
__insn32_query() will not compile if the compiler decides to not
inline it, since it contains an inline assembly with an "i" constraint
with variable contents.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The inline assembly constraints of __insn32_query() tell the compiler
that only the first byte of "query" is being written to. Intended was
probably that 32 bytes are written to.
Fix and simplify the code and just use a "memory" clobber.
Fixes: d668139718 ("KVM: s390: provide query function for instructions returning 32 byte")
Cc: stable@vger.kernel.org # v5.2+
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
In commit 43d8ce9d65 ("Provide in-kernel headers to make
extending kernel easier") a new mechanism was introduced, for kernels
>=5.2, which embeds the kernel headers in the kernel image or a module
and exposes them in procfs for use by userland tools.
The archive containing the header files has nondeterminism caused by
header files metadata. This patch normalizes the metadata and utilizes
KBUILD_BUILD_TIMESTAMP if provided and otherwise falls back to the
default behaviour.
In commit f7b101d330 ("kheaders: Move from proc to sysfs") it was
modified to use sysfs and the script for generation of the archive was
renamed to what is being patched.
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
