linux-stable.git/arch/arm64/kernel, branch linux-5.0.y Linux kernel stable tree arm64: cpu_ops: fix a leaked reference by adding missing of_node_put 2019-05-31T13:45:12+00:00 Wen Yang wen.yang99@zte.com.cn 2019-03-05T11:34:05+00:00 685f8804590f74aa1d7008e662c397e4b41c4003 [ Upstream commit 92606ec9285fb84cd9b5943df23f07d741384bfc ] The call to of_get_next_child returns a node pointer with refcount incremented thus it must be explicitly decremented after the last usage. Detected by coccinelle with the following warnings: ./arch/arm64/kernel/cpu_ops.c:102:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 69, but without a corresponding object release within this function. Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 92606ec9285fb84cd9b5943df23f07d741384bfc ]

The call to of_get_next_child returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
  ./arch/arm64/kernel/cpu_ops.c:102:1-7: ERROR: missing of_node_put;
  acquired a node pointer with refcount incremented on line 69, but
  without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: vdso: Fix clock_getres() for CLOCK_REALTIME 2019-05-31T13:45:05+00:00 Vincenzo Frascino vincenzo.frascino@arm.com 2019-04-16T16:14:30+00:00 d306fa351148b04a158b208439d11f77df10145d [ Upstream commit 81fb8736dd81da3fe94f28968dac60f392ec6746 ] clock_getres() in the vDSO library has to preserve the same behaviour of posix_get_hrtimer_res(). In particular, posix_get_hrtimer_res() does: sec = 0; ns = hrtimer_resolution; where 'hrtimer_resolution' depends on whether or not high resolution timers are enabled, which is a runtime decision. The vDSO incorrectly returns the constant CLOCK_REALTIME_RES. Fix this by exposing 'hrtimer_resolution' in the vDSO datapage and returning that instead. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> [will: Use WRITE_ONCE(), move adr off COARSE path, renumber labels, use 'w' reg] Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 81fb8736dd81da3fe94f28968dac60f392ec6746 ]

clock_getres() in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().

In particular, posix_get_hrtimer_res() does:

    sec = 0;
    ns = hrtimer_resolution;

where 'hrtimer_resolution' depends on whether or not high resolution
timers are enabled, which is a runtime decision.

The vDSO incorrectly returns the constant CLOCK_REALTIME_RES. Fix this
by exposing 'hrtimer_resolution' in the vDSO datapage and returning that
instead.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[will: Use WRITE_ONCE(), move adr off COARSE path, renumber labels, use 'w' reg]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: errata: Add workaround for Cortex-A76 erratum #1463225 2019-05-31T13:44:47+00:00 Will Deacon will.deacon@arm.com 2019-04-29T12:03:57+00:00 e4c2027048b048079fb1b306fe365921a14a055f commit 969f5ea627570e91c9d54403287ee3ed657f58fe upstream. Revisions of the Cortex-A76 CPU prior to r4p0 are affected by an erratum that can prevent interrupts from being taken when single-stepping. This patch implements a software workaround to prevent userspace from effectively being able to disable interrupts. Cc: <stable@vger.kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 969f5ea627570e91c9d54403287ee3ed657f58fe upstream.

Revisions of the Cortex-A76 CPU prior to r4p0 are affected by an erratum
that can prevent interrupts from being taken when single-stepping.

This patch implements a software workaround to prevent userspace from
effectively being able to disable interrupts.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64/kernel: kaslr: reduce module randomization range to 2 GB 2019-05-31T13:44:45+00:00 Ard Biesheuvel ard.biesheuvel@arm.com 2019-05-23T09:17:37+00:00 ea6a37ae940e99fb49386a75a45825156d9a415d commit b2eed9b58811283d00fa861944cb75797d4e52a7 upstream. The following commit 7290d5809571 ("module: use relative references for __ksymtab entries") updated the ksymtab handling of some KASLR capable architectures so that ksymtab entries are emitted as pairs of 32-bit relative references. This reduces the size of the entries, but more importantly, it gets rid of statically assigned absolute addresses, which require fixing up at boot time if the kernel is self relocating (which takes a 24 byte RELA entry for each member of the ksymtab struct). Since ksymtab entries are always part of the same module as the symbol they export, it was assumed at the time that a 32-bit relative reference is always sufficient to capture the offset between a ksymtab entry and its target symbol. Unfortunately, this is not always true: in the case of per-CPU variables, a per-CPU variable's base address (which usually differs from the actual address of any of its per-CPU copies) is allocated in the vicinity of the ..data.percpu section in the core kernel (i.e., in the per-CPU reserved region which follows the section containing the core kernel's statically allocated per-CPU variables). Since we randomize the module space over a 4 GB window covering the core kernel (based on the -/+ 4 GB range of an ADRP/ADD pair), we may end up putting the core kernel out of the -/+ 2 GB range of 32-bit relative references of module ksymtab entries that refer to per-CPU variables. So reduce the module randomization range a bit further. We lose 1 bit of randomization this way, but this is something we can tolerate. Cc: <stable@vger.kernel.org> # v4.19+ Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b2eed9b58811283d00fa861944cb75797d4e52a7 upstream.

The following commit

  7290d5809571 ("module: use relative references for __ksymtab entries")

updated the ksymtab handling of some KASLR capable architectures
so that ksymtab entries are emitted as pairs of 32-bit relative
references. This reduces the size of the entries, but more
importantly, it gets rid of statically assigned absolute
addresses, which require fixing up at boot time if the kernel
is self relocating (which takes a 24 byte RELA entry for each
member of the ksymtab struct).

Since ksymtab entries are always part of the same module as the
symbol they export, it was assumed at the time that a 32-bit
relative reference is always sufficient to capture the offset
between a ksymtab entry and its target symbol.

Unfortunately, this is not always true: in the case of per-CPU
variables, a per-CPU variable's base address (which usually differs
from the actual address of any of its per-CPU copies) is allocated
in the vicinity of the ..data.percpu section in the core kernel
(i.e., in the per-CPU reserved region which follows the section
containing the core kernel's statically allocated per-CPU variables).

Since we randomize the module space over a 4 GB window covering
the core kernel (based on the -/+ 4 GB range of an ADRP/ADD pair),
we may end up putting the core kernel out of the -/+ 2 GB range of
32-bit relative references of module ksymtab entries that refer to
per-CPU variables.

So reduce the module randomization range a bit further. We lose
1 bit of randomization this way, but this is something we can
tolerate.

Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: Clear OSDLR_EL1 on CPU boot 2019-05-22T05:38:36+00:00 Jean-Philippe Brucker jean-philippe.brucker@arm.com 2019-04-08T17:17:18+00:00 bd254f9d1157194586d1b535387e377306149d7b commit 6fda41bf12615ee7c3ddac88155099b1a8cf8d00 upstream. Some firmwares may reboot CPUs with OS Double Lock set. Make sure that it is unlocked, in order to use debug exceptions. Cc: <stable@vger.kernel.org> Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6fda41bf12615ee7c3ddac88155099b1a8cf8d00 upstream.

Some firmwares may reboot CPUs with OS Double Lock set. Make sure that
it is unlocked, in order to use debug exceptions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: arch_timer: Ensure counter register reads occur with seqlock held 2019-05-22T05:38:36+00:00 Will Deacon will.deacon@arm.com 2019-04-29T16:26:22+00:00 e57320e0177a27634263aa020b7ede884b7f72b8 commit 75a19a0202db21638a1c2b424afb867e1f9a2376 upstream. When executing clock_gettime(), either in the vDSO or via a system call, we need to ensure that the read of the counter register occurs within the seqlock reader critical section. This ensures that updates to the clocksource parameters (e.g. the multiplier) are consistent with the counter value and therefore avoids the situation where time appears to go backwards across multiple reads. Extend the vDSO logic so that the seqlock critical section covers the read of the counter register as well as accesses to the data page. Since reads of the counter system registers are not ordered by memory barrier instructions, introduce dependency ordering from the counter read to a subsequent memory access so that the seqlock memory barriers apply to the counter access in both the vDSO and the system call paths. Cc: <stable@vger.kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/ Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 75a19a0202db21638a1c2b424afb867e1f9a2376 upstream.

When executing clock_gettime(), either in the vDSO or via a system call,
we need to ensure that the read of the counter register occurs within
the seqlock reader critical section. This ensures that updates to the
clocksource parameters (e.g. the multiplier) are consistent with the
counter value and therefore avoids the situation where time appears to
go backwards across multiple reads.

Extend the vDSO logic so that the seqlock critical section covers the
read of the counter register as well as accesses to the data page. Since
reads of the counter system registers are not ordered by memory barrier
instructions, introduce dependency ordering from the counter read to a
subsequent memory access so that the seqlock memory barriers apply to
the counter access in both the vDSO and the system call paths.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: mmap: Ensure file offset is treated as unsigned 2019-05-22T05:38:36+00:00 Boyang Zhou zhouby_cn@126.com 2019-04-29T14:27:19+00:00 32e802d947ca415b11d27c4adda63044ff184100 commit f08cae2f28db24d95be5204046b60618d8de4ddc upstream. The file offset argument to the arm64 sys_mmap() implementation is scaled from bytes to pages by shifting right by PAGE_SHIFT. Unfortunately, the offset is passed in as a signed 'off_t' type and therefore large offsets (i.e. with the top bit set) are incorrectly sign-extended by the shift. This has been observed to cause false mmap() failures when mapping GPU doorbells on an arm64 server part. Change the type of the file offset argument to sys_mmap() from 'off_t' to 'unsigned long' so that the shifting scales the value as expected. Cc: <stable@vger.kernel.org> Signed-off-by: Boyang Zhou <zhouby_cn@126.com> [will: rewrote commit message] Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f08cae2f28db24d95be5204046b60618d8de4ddc upstream.

The file offset argument to the arm64 sys_mmap() implementation is
scaled from bytes to pages by shifting right by PAGE_SHIFT.
Unfortunately, the offset is passed in as a signed 'off_t' type and
therefore large offsets (i.e. with the top bit set) are incorrectly
sign-extended by the shift. This has been observed to cause false mmap()
failures when mapping GPU doorbells on an arm64 server part.

Change the type of the file offset argument to sys_mmap() from 'off_t'
to 'unsigned long' so that the shifting scales the value as expected.

Cc: <stable@vger.kernel.org>
Signed-off-by: Boyang Zhou <zhouby_cn@126.com>
[will: rewrote commit message]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64/module: ftrace: deal with place relative nature of PLTs 2019-05-16T17:40:24+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2019-04-13T06:59:25+00:00 28e4593bb1489f2dbb6406b4130337246e63d1a0 [ Upstream commit 4e69ecf4da1ee0b2ac735e1f1bb13935acd5a38d ] Another bodge for the ftrace PLT code: plt_entries_equal() now takes the place relative nature of the ADRP/ADD based PLT entries into account, which means that a struct trampoline instance on the stack is no longer equal to the same set of opcodes in the module struct, given that they don't point to the same place in memory anymore. Work around this by using memcmp() in the ftrace PLT handling code. Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: dann frazier <dann.frazier@canonical.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4e69ecf4da1ee0b2ac735e1f1bb13935acd5a38d ]

Another bodge for the ftrace PLT code: plt_entries_equal() now takes
the place relative nature of the ADRP/ADD based PLT entries into
account, which means that a struct trampoline instance on the stack
is no longer equal to the same set of opcodes in the module struct,
given that they don't point to the same place in memory anymore.

Work around this by using memcmp() in the ftrace PLT handling code.

Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: fix wrong check of on_sdei_stack in nmi context 2019-05-08T05:22:53+00:00 Wei Li liwei391@huawei.com 2019-04-01T03:55:57+00:00 26ac3d804822b757a6a4f73c0497bc9404f9a8e1 [ Upstream commit 1c41860864c8ae0387ef7d44f0000e99cbb2e06d ] When doing unwind_frame() in the context of pseudo nmi (need enable CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0, pc != 0), function on_sdei_stack() will return true while the sdei acpi table is not inited in fact. This will cause a "NULL pointer dereference" oops when going on. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org> 
[ Upstream commit 1c41860864c8ae0387ef7d44f0000e99cbb2e06d ]

When doing unwind_frame() in the context of pseudo nmi (need enable
CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0,
pc != 0), function on_sdei_stack() will return true while the sdei acpi
table is not inited in fact. This will cause a "NULL pointer dereference"
oops when going on.

Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
arm64/ftrace: fix inadvertent BUG() in trampoline check 2019-04-17T06:39:52+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2019-04-07T19:06:16+00:00 6b3b09cd4daa81bab35375f54c4548dea930c238 commit 5a3ae7b314a2259b1188b22b392f5eba01e443ee upstream. The ftrace trampoline code (which deals with modules loaded out of BL range of the core kernel) uses plt_entries_equal() to check whether the per-module trampoline equals a zero buffer, to decide whether the trampoline has already been initialized. This triggers a BUG() in the opcode manipulation code, since we end up checking the ADRP offset of a 0x0 opcode, which is not an ADRP instruction. So instead, add a helper to check whether a PLT is initialized, and call that from the frace code. Cc: <stable@vger.kernel.org> # v5.0 Fixes: bdb85cd1d206 ("arm64/module: switch to ADRP/ADD sequences for PLT entries") Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5a3ae7b314a2259b1188b22b392f5eba01e443ee upstream.

The ftrace trampoline code (which deals with modules loaded out of
BL range of the core kernel) uses plt_entries_equal() to check whether
the per-module trampoline equals a zero buffer, to decide whether the
trampoline has already been initialized.

This triggers a BUG() in the opcode manipulation code, since we end
up checking the ADRP offset of a 0x0 opcode, which is not an ADRP
instruction.

So instead, add a helper to check whether a PLT is initialized, and
call that from the frace code.

Cc: <stable@vger.kernel.org> # v5.0
Fixes: bdb85cd1d206 ("arm64/module: switch to ADRP/ADD sequences for PLT entries")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>