Commit graph

118141 commits

Author SHA1 Message Date
Masami Hiramatsu
3dda8d29b5 x86/kprobes: Verify stack frame on kretprobe
commit 3ff9c075cc767b3060bdac12da72fc94dd7da1b8 upstream.

Verify the stack frame pointer on kretprobe trampoline handler,
If the stack frame pointer does not match, it skips the wrong
entry and tries to find correct one.

This can happen if user puts the kretprobe on the function
which can be used in the path of ftrace user-function call.
Such functions should not be probed, so this adds a warning
message that reports which function should be blacklisted.

Tested-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/155094059185.6137.15527904013362842072.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:34:02 +02:00
Nathan Chancellor
bc76b595cd arm64: futex: Restore oldval initialization to work around buggy compilers
commit ff8acf929014b7f87315588e0daf8597c8aa9d1c upstream.

Commit 045afc24124d ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with
non-zero result value") removed oldval's zero initialization in
arch_futex_atomic_op_inuser because it is not necessary. Unfortunately,
Android's arm64 GCC 4.9.4 [1] does not agree:

../kernel/futex.c: In function 'do_futex':
../kernel/futex.c:1658:17: warning: 'oldval' may be used uninitialized
in this function [-Wmaybe-uninitialized]
   return oldval == cmparg;
                 ^
In file included from ../kernel/futex.c:73:0:
../arch/arm64/include/asm/futex.h:53:6: note: 'oldval' was declared here
  int oldval, ret, tmp;
      ^

GCC fails to follow that when ret is non-zero, futex_atomic_op_inuser
returns right away, avoiding the uninitialized use that it claims.
Restoring the zero initialization works around this issue.

[1]: https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/

Cc: stable@vger.kernel.org
Fixes: 045afc24124d ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:34:01 +02:00
Eric Biggers
7977328f42 crypto: x86/poly1305 - fix overflow during partial reduction
commit 678cce4019d746da6c680c48ba9e6d417803e127 upstream.

The x86_64 implementation of Poly1305 produces the wrong result on some
inputs because poly1305_4block_avx2() incorrectly assumes that when
partially reducing the accumulator, the bits carried from limb 'd4' to
limb 'h0' fit in a 32-bit integer.  This is true for poly1305-generic
which processes only one block at a time.  However, it's not true for
the AVX2 implementation, which processes 4 blocks at a time and
therefore can produce intermediate limbs about 4x larger.

Fix it by making the relevant calculations use 64-bit arithmetic rather
than 32-bit.  Note that most of the carries already used 64-bit
arithmetic, but the d4 -> h0 carry was different for some reason.

To be safe I also made the same change to the corresponding SSE2 code,
though that only operates on 1 or 2 blocks at a time.  I don't think
it's really needed for poly1305_block_sse2(), but it doesn't hurt
because it's already x86_64 code.  It *might* be needed for
poly1305_2block_sse2(), but overflows aren't easy to reproduce there.

This bug was originally detected by my patches that improve testmgr to
fuzz algorithms against their generic implementation.  But also add a
test vector which reproduces it directly (in the AVX2 case).

Fixes: b1ccc8f4b6 ("crypto: poly1305 - Add a four block AVX2 variant for x86_64")
Fixes: c70f4abef0 ("crypto: poly1305 - Add a SSE2 SIMD variant for x86_64")
Cc: <stable@vger.kernel.org> # v4.3+
Cc: Martin Willi <martin@strongswan.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:34:01 +02:00
Sean Christopherson
eaa303a2d6 KVM: x86: Don't clear EFER during SMM transitions for 32-bit vCPU
commit 8f4dc2e77cdfaf7e644ef29693fa229db29ee1de upstream.

Neither AMD nor Intel CPUs have an EFER field in the legacy SMRAM save
state area, i.e. don't save/restore EFER across SMM transitions.  KVM
somewhat models this, e.g. doesn't clear EFER on entry to SMM if the
guest doesn't support long mode.  But during RSM, KVM unconditionally
clears EFER so that it can get back to pure 32-bit mode in order to
start loading CRs with their actual non-SMM values.

Clear EFER only when it will be written when loading the non-SMM state
so as to preserve bits that can theoretically be set on 32-bit vCPUs,
e.g. KVM always emulates EFER_SCE.

And because CR4.PAE is cleared only to play nice with EFER, wrap that
code in the long mode check as well.  Note, this may result in a
compiler warning about cr4 being consumed uninitialized.  Re-read CR4
even though it's technically unnecessary, as doing so allows for more
readable code and RSM emulation is not a performance critical path.

Fixes: 660a5d517a ("KVM: x86: save/load state on SMM switch")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:34:01 +02:00
Yang Shi
4528b128bb ARM: 8839/1: kprobe: make patch_lock a raw_spinlock_t
[ Upstream commit 143c2a89e0e5fda6c6fd08d7bc1126438c19ae90 ]

When running kprobe on -rt kernel, the below bug is caught:

|BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:931
|in_atomic(): 1, irqs_disabled(): 128, pid: 14, name: migration/0
|Preemption disabled at:[<802f2b98>] cpu_stopper_thread+0xc0/0x140
|CPU: 0 PID: 14 Comm: migration/0 Tainted: G O 4.8.3-rt2 #1
|Hardware name: Freescale LS1021A
|[<8025a43c>] (___might_sleep)
|[<80b5b324>] (rt_spin_lock)
|[<80b5c31c>] (__patch_text_real)
|[<80b5c3ac>] (patch_text_stop_machine)
|[<802f2920>] (multi_cpu_stop)

Since patch_text_stop_machine() is called in stop_machine() which
disables IRQ, sleepable lock should be not used in this atomic context,
 so replace patch_lock to raw lock.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:59 +02:00
Ard Biesheuvel
cc8c23ad5e crypto: sha512/arm - fix crash bug in Thumb2 build
[ Upstream commit c64316502008064c158fa40cc250665e461b0f2a ]

The SHA512 code we adopted from the OpenSSL project uses a rather
peculiar way to take the address of the round constant table: it
takes the address of the sha256_block_data_order() routine, and
substracts a constant known quantity to arrive at the base of the
table, which is emitted by the same assembler code right before
the routine's entry point.

However, recent versions of binutils have helpfully changed the
behavior of references emitted via an ADR instruction when running
in Thumb2 mode: it now takes the Thumb execution mode bit into
account, which is bit 0 af the address. This means the produced
table address also has bit 0 set, and so we end up with an address
value pointing 1 byte past the start of the table, which results
in crashes such as

  Unable to handle kernel paging request at virtual address bf825000
  pgd = 42f44b11
  [bf825000] *pgd=80000040206003, *pmd=5f1bd003, *pte=00000000
  Internal error: Oops: 207 [#1] PREEMPT SMP THUMB2
  Modules linked in: sha256_arm(+) sha1_arm_ce sha1_arm ...
  CPU: 7 PID: 396 Comm: cryptomgr_test Not tainted 5.0.0-rc6+ #144
  Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
  PC is at sha256_block_data_order+0xaaa/0xb30 [sha256_arm]
  LR is at __this_module+0x17fd/0xffffe800 [sha256_arm]
  pc : [<bf820bca>]    lr : [<bf824ffd>]    psr: 800b0033
  sp : ebc8bbe8  ip : faaabe1c  fp : 2fdd3433
  r10: 4c5f1692  r9 : e43037df  r8 : b04b0a5a
  r7 : c369d722  r6 : 39c3693e  r5 : 7a013189  r4 : 1580d26b
  r3 : 8762a9b0  r2 : eea9c2cd  r1 : 3e9ab536  r0 : 1dea4ae7
  Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA Thumb  Segment user
  Control: 70c5383d  Table: 6b8467c0  DAC: dbadc0de
  Process cryptomgr_test (pid: 396, stack limit = 0x69e1fe23)
  Stack: (0xebc8bbe8 to 0xebc8c000)
  ...
  unwind: Unknown symbol address bf820bca
  unwind: Index not found bf820bca
  Code: 441a ea80 40f9 440a (f85e) 3b04
  ---[ end trace e560cce92700ef8a ]---

Given that this affects older kernels as well, in case they are built
with a recent toolchain, apply a minimal backportable fix, which is
to emit another non-code label at the start of the routine, and
reference that instead. (This is similar to the current upstream state
of this file in OpenSSL)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:59 +02:00
Ard Biesheuvel
8a2dd49a63 crypto: sha256/arm - fix crash bug in Thumb2 build
[ Upstream commit 69216a545cf81b2b32d01948f7039315abaf75a0 ]

The SHA256 code we adopted from the OpenSSL project uses a rather
peculiar way to take the address of the round constant table: it
takes the address of the sha256_block_data_order() routine, and
substracts a constant known quantity to arrive at the base of the
table, which is emitted by the same assembler code right before
the routine's entry point.

However, recent versions of binutils have helpfully changed the
behavior of references emitted via an ADR instruction when running
in Thumb2 mode: it now takes the Thumb execution mode bit into
account, which is bit 0 af the address. This means the produced
table address also has bit 0 set, and so we end up with an address
value pointing 1 byte past the start of the table, which results
in crashes such as

  Unable to handle kernel paging request at virtual address bf825000
  pgd = 42f44b11
  [bf825000] *pgd=80000040206003, *pmd=5f1bd003, *pte=00000000
  Internal error: Oops: 207 [#1] PREEMPT SMP THUMB2
  Modules linked in: sha256_arm(+) sha1_arm_ce sha1_arm ...
  CPU: 7 PID: 396 Comm: cryptomgr_test Not tainted 5.0.0-rc6+ #144
  Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
  PC is at sha256_block_data_order+0xaaa/0xb30 [sha256_arm]
  LR is at __this_module+0x17fd/0xffffe800 [sha256_arm]
  pc : [<bf820bca>]    lr : [<bf824ffd>]    psr: 800b0033
  sp : ebc8bbe8  ip : faaabe1c  fp : 2fdd3433
  r10: 4c5f1692  r9 : e43037df  r8 : b04b0a5a
  r7 : c369d722  r6 : 39c3693e  r5 : 7a013189  r4 : 1580d26b
  r3 : 8762a9b0  r2 : eea9c2cd  r1 : 3e9ab536  r0 : 1dea4ae7
  Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA Thumb  Segment user
  Control: 70c5383d  Table: 6b8467c0  DAC: dbadc0de
  Process cryptomgr_test (pid: 396, stack limit = 0x69e1fe23)
  Stack: (0xebc8bbe8 to 0xebc8c000)
  ...
  unwind: Unknown symbol address bf820bca
  unwind: Index not found bf820bca
  Code: 441a ea80 40f9 440a (f85e) 3b04
  ---[ end trace e560cce92700ef8a ]---

Given that this affects older kernels as well, in case they are built
with a recent toolchain, apply a minimal backportable fix, which is
to emit another non-code label at the start of the routine, and
reference that instead. (This is similar to the current upstream state
of this file in OpenSSL)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:58 +02:00
Bartlomiej Zolnierkiewicz
1e3975db46 ARM: samsung: Limit SAMSUNG_PM_CHECK config option to non-Exynos platforms
[ Upstream commit 6862fdf2201ab67cd962dbf0643d37db909f4860 ]

"S3C2410 PM Suspend Memory CRC" feature (controlled by
SAMSUNG_PM_CHECK config option) is incompatible with highmem
(uses phys_to_virt() instead of proper mapping) which is used by
the majority of Exynos boards. The issue manifests itself in OOPS
on affected boards, i.e. on Odroid-U3 I got the following one:

Unable to handle kernel paging request at virtual address f0000000
pgd = 1c0f9bb4
[f0000000] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[<c0458034>] (crc32_le) from [<c0121f8c>] (s3c_pm_makecheck+0x34/0x54)
[<c0121f8c>] (s3c_pm_makecheck) from [<c0121efc>] (s3c_pm_run_res+0x74/0x8c)
[<c0121efc>] (s3c_pm_run_res) from [<c0121ecc>] (s3c_pm_run_res+0x44/0x8c)
[<c0121ecc>] (s3c_pm_run_res) from [<c01210b8>] (exynos_suspend_enter+0x64/0x148)
[<c01210b8>] (exynos_suspend_enter) from [<c018893c>] (suspend_devices_and_enter+0x9ec/0xe74)
[<c018893c>] (suspend_devices_and_enter) from [<c0189534>] (pm_suspend+0x770/0xc04)
[<c0189534>] (pm_suspend) from [<c0186ce8>] (state_store+0x6c/0xcc)
[<c0186ce8>] (state_store) from [<c09db434>] (kobj_attr_store+0x14/0x20)
[<c09db434>] (kobj_attr_store) from [<c02fa63c>] (sysfs_kf_write+0x4c/0x50)
[<c02fa63c>] (sysfs_kf_write) from [<c02f97a4>] (kernfs_fop_write+0xfc/0x1e4)
[<c02f97a4>] (kernfs_fop_write) from [<c027b198>] (__vfs_write+0x2c/0x140)
[<c027b198>] (__vfs_write) from [<c027b418>] (vfs_write+0xa4/0x160)
[<c027b418>] (vfs_write) from [<c027b5d8>] (ksys_write+0x40/0x8c)
[<c027b5d8>] (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x28)

Add PLAT_S3C24XX, ARCH_S3C64XX and ARCH_S5PV210 dependencies to
SAMSUNG_PM_CHECK config option to hide it on Exynos platforms.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:58 +02:00
Nathan Chancellor
35ee305cfe x86/hw_breakpoints: Make default case in hw_breakpoint_arch_parse() return an error
[ Upstream commit e898e69d6b9475bf123f99b3c5d1a67bb7cb2361 ]

When building with -Wsometimes-uninitialized, Clang warns:

arch/x86/kernel/hw_breakpoint.c:355:2: warning: variable 'align' is used
uninitialized whenever switch default is taken
[-Wsometimes-uninitialized]

The default cannot be reached because arch_build_bp_info() initializes
hw->len to one of the specified cases. Nevertheless the warning is valid
and returning -EINVAL makes sure that this cannot be broken by future
modifications.

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: clang-built-linux@googlegroups.com
Link: https://github.com/ClangBuiltLinux/linux/issues/392
Link: https://lkml.kernel.org/r/20190307212756.4648-1-natechancellor@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:57 +02:00
Matthew Whitehead
1a883611e2 x86/cpu/cyrix: Use correct macros for Cyrix calls on Geode processors
[ Upstream commit 18fb053f9b827bd98cfc64f2a35df8ab19745a1d ]

There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:

  setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:

  outb(CX86_CCR2, 0x22);
  inb(0x23);

From the comments:

 * When using the old macros a line like
 *   setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 * gets expanded to:
 *  do {
 *    outb((CX86_CCR2), 0x22);
 *    outb((({
 *        outb((CX86_CCR2), 0x22);
 *        inb(0x23);
 *    }) | 0x88), 0x23);
 *  } while (0);

The new macros fix this problem, so use them instead. Tested on an
actual Geode processor.

Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: luto@kernel.org
Link: https://lkml.kernel.org/r/1552596361-8967-2-git-send-email-tedheadster@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:57 +02:00
Aditya Pakki
c2dc2fdc0c x86/hpet: Prevent potential NULL pointer dereference
[ Upstream commit 2e84f116afca3719c9d0a1a78b47b48f75fd5724 ]

hpet_virt_address may be NULL when ioremap_nocache fail, but the code lacks
a check.

Add a check to prevent NULL pointer dereference.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kjlu@umn.edu
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Roland Dreier <roland@purestorage.com>
Link: https://lkml.kernel.org/r/20190319021958.17275-1-pakki001@umn.edu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:57 +02:00
Max Filippov
34419534a7 xtensa: fix return_address
commit ada770b1e74a77fff2d5f539bf6c42c25f4784db upstream.

return_address returns the address that is one level higher in the call
stack than requested in its argument, because level 0 corresponds to its
caller's return address. Use requested level as the number of stack
frames to skip.

This fixes the address reported by might_sleep and friends.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:56 +02:00
Dan Carpenter
c082a57d41 xen: Prevent buffer overflow in privcmd ioctl
commit 42d8644bd77dd2d747e004e367cb0c895a606f39 upstream.

The "call" variable comes from the user in privcmd_ioctl_hypercall().
It's an offset into the hypercall_page[] which has (PAGE_SIZE / 32)
elements.  We need to put an upper bound on it to prevent an out of
bounds access.

Cc: stable@vger.kernel.org
Fixes: 1246ae0bb9 ("xen: add variable hypercall caller")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:56 +02:00
Will Deacon
442ebc6852 arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value
commit 045afc24124d80c6998d9c770844c67912083506 upstream.

Rather embarrassingly, our futex() FUTEX_WAKE_OP implementation doesn't
explicitly set the return value on the non-faulting path and instead
leaves it holding the result of the underlying atomic operation. This
means that any FUTEX_WAKE_OP atomic operation which computes a non-zero
value will be reported as having failed. Regrettably, I wrote the buggy
code back in 2011 and it was upstreamed as part of the initial arm64
support in 2012.

The reasons we appear to get away with this are:

  1. FUTEX_WAKE_OP is rarely used and therefore doesn't appear to get
     exercised by futex() test applications

  2. If the result of the atomic operation is zero, the system call
     behaves correctly

  3. Prior to version 2.25, the only operation used by GLIBC set the
     futex to zero, and therefore worked as expected. From 2.25 onwards,
     FUTEX_WAKE_OP is not used by GLIBC at all.

Fix the implementation by ensuring that the return value is either 0
to indicate that the atomic operation completed successfully, or -EFAULT
if we encountered a fault when accessing the user mapping.

Cc: <stable@kernel.org>
Fixes: 6170a97460 ("arm64: Atomic operations")
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:56 +02:00
David Engraf
e9b63a38da ARM: dts: at91: Fix typo in ISC_D0 on PC9
commit e7dfb6d04e4715be1f3eb2c60d97b753fd2e4516 upstream.

The function argument for the ISC_D0 on PC9 was incorrect. According to
the documentation it should be 'C' aka 3.

Signed-off-by: David Engraf <david.engraf@sysgo.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Fixes: 7f16cb676c ("ARM: at91/dt: add sama5d2 pinmux")
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:55 +02:00
Nick Desaulniers
7c45b45fd6 x86/vdso: Drop implicit common-page-size linker flag
commit ac3e233d29f7f77f28243af0132057d378d3ea58 upstream.

GNU linker's -z common-page-size's default value is based on the target
architecture. arch/x86/entry/vdso/Makefile sets it to the architecture
default, which is implicit and redundant. Drop it.

Fixes: 2aae950b21 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu")
Reported-by: Dmitry Golovin <dima@golovin.in>
Reported-by: Bill Wendling <morbo@google.com>
Suggested-by: Dmitry Golovin <dima@golovin.in>
Suggested-by: Rui Ueyama <ruiu@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Fangrui Song <maskray@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181206191231.192355-1-ndesaulniers@google.com
Link: https://bugs.llvm.org/show_bug.cgi?id=38774
Link: https://github.com/ClangBuiltLinux/linux/issues/31
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:54 +02:00
Alistair Strachan
79739ad2d0 x86: vdso: Use $LD instead of $CC to link
commit 379d98ddf41344273d9718556f761420f4dc80b3 upstream.

The vdso{32,64}.so can fail to link with CC=clang when clang tries to find
a suitable GCC toolchain to link these libraries with.

/usr/bin/ld: arch/x86/entry/vdso/vclock_gettime.o:
  access beyond end of merged section (782)

This happens because the host environment leaked into the cross compiler
environment due to the way clang searches for suitable GCC toolchains.

Clang is a retargetable compiler, and each invocation of it must provide
--target=<something> --gcc-toolchain=<something> to allow it to find the
correct binutils for cross compilation. These flags had been added to
KBUILD_CFLAGS, but the vdso code uses CC and not KBUILD_CFLAGS (for various
reasons) which breaks clang's ability to find the correct linker when cross
compiling.

Most of the time this goes unnoticed because the host linker is new enough
to work anyway, or is incompatible and skipped, but this cannot be reliably
assumed.

This change alters the vdso makefile to just use LD directly, which
bypasses clang and thus the searching problem. The makefile will just use
${CROSS_COMPILE}ld instead, which is always what we want. This matches the
method used to link vmlinux.

This drops references to DISABLE_LTO; this option doesn't seem to be set
anywhere, and not knowing what its possible values are, it's not clear how
to convert it from CC to LD flag.

Signed-off-by: Alistair Strachan <astrachan@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: kernel-team@android.com
Cc: joel@joelfernandes.org
Cc: Andi Kleen <andi.kleen@intel.com>
Link: https://lkml.kernel.org/r/20180803173931.117515-1-astrachan@google.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:54 +02:00
George Rimar
b79e268b1f x86/build: Specify elf_i386 linker emulation explicitly for i386 objects
commit 927185c124d62a9a4d35878d7f6d432a166b74e3 upstream.

The kernel uses the OUTPUT_FORMAT linker script command in it's linker
scripts. Most of the time, the -m option is passed to the linker with
correct architecture, but sometimes (at least for x86_64) the -m option
contradicts the OUTPUT_FORMAT directive.

Specifically, arch/x86/boot and arch/x86/realmode/rm produce i386 object
files, but are linked with the -m elf_x86_64 linker flag when building
for x86_64.

The GNU linker manpage doesn't explicitly state any tie-breakers between
-m and OUTPUT_FORMAT. But with BFD and Gold linkers, OUTPUT_FORMAT
overrides the emulation value specified with the -m option.

LLVM lld has a different behavior, however. When supplied with
contradicting -m and OUTPUT_FORMAT values it fails with the following
error message:

  ld.lld: error: arch/x86/realmode/rm/header.o is incompatible with elf_x86_64

Therefore, just add the correct -m after the incorrect one (it overrides
it), so the linker invocation looks like this:

  ld -m elf_x86_64 -z max-page-size=0x200000 -m elf_i386 --emit-relocs -T \
    realmode.lds header.o trampoline_64.o stack.o reboot.o -o realmode.elf

This is not a functional change for GNU ld, because (although not
explicitly documented) OUTPUT_FORMAT overrides -m EMULATION.

Tested by building x86_64 kernel with GNU gcc/ld toolchain and booting
it in QEMU.

 [ bp: massage and clarify text. ]

Suggested-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: George Rimar <grimar@accesssoftek.com>
Signed-off-by: Tri Vo <trong@android.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Tri Vo <trong@android.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Matz <matz@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: morbo@google.com
Cc: ndesaulniers@google.com
Cc: ruiu@google.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190111201012.71210-1-trong@android.com
[nc: Fix conflicts due to lack of commit 58ab5e0c2c40 ("Kbuild: arch:
     look for generated headers in obtree") in this tree]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:53 +02:00
Rafael Ávila de Espíndola
589562152f x86/build: Mark per-CPU symbols as absolute explicitly for LLD
[ Upstream commit d071ae09a4a1414c1433d5ae9908959a7325b0ad ]

Accessing per-CPU variables is done by finding the offset of the
variable in the per-CPU block and adding it to the address of the
respective CPU's block.

Section 3.10.8 of ld.bfd's documentation states:

  For expressions involving numbers, relative addresses and absolute
  addresses, ld follows these rules to evaluate terms:

  Other binary operations, that is, between two relative addresses
  not in the same section, or between a relative address and an
  absolute address, first convert any non-absolute term to an
  absolute address before applying the operator."

Note that LLVM's linker does not adhere to the GNU ld's implementation
and as such requires implicitly-absolute terms to be explicitly marked
as absolute in the linker script. If not, it fails currently with:

  ld.lld: error: ./arch/x86/kernel/vmlinux.lds:153: at least one side of the expression must be absolute
  ld.lld: error: ./arch/x86/kernel/vmlinux.lds:154: at least one side of the expression must be absolute
  Makefile:1040: recipe for target 'vmlinux' failed

This is not a functional change for ld.bfd which converts the term to an
absolute symbol anyways as specified above.

Based on a previous submission by Tri Vo <trong@android.com>.

Reported-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: Rafael Ávila de Espíndola <rafael@espindo.la>
[ Update commit message per Boris' and Michael's suggestions. ]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
[ Massage commit message more, fix typos. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Dmitry Golovin <dima@golovin.in>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Cao Jin <caoj.fnst@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tri Vo <trong@android.com>
Cc: dima@golovin.in
Cc: morbo@google.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181219190145.252035-1-ndesaulniers@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:53 +02:00
Russell King
d9c190a5ee ARM: avoid Cortex-A9 livelock on tight dmb loops
[ Upstream commit 5388a5b82199facacd3d7ac0d05aca6e8f902fed ]

machine_crash_nonpanic_core() does this:

	while (1)
		cpu_relax();

because the kernel has crashed, and we have no known safe way to deal
with the CPU.  So, we place the CPU into an infinite loop which we
expect it to never exit - at least not until the system as a whole is
reset by some method.

In the absence of erratum 754327, this code assembles to:

	b	.

In other words, an infinite loop.  When erratum 754327 is enabled,
this becomes:

1:	dmb
	b	1b

It has been observed that on some systems (eg, OMAP4) where, if a
crash is triggered, the system tries to kexec into the panic kernel,
but fails after taking the secondary CPU down - placing it into one
of these loops.  This causes the system to livelock, and the most
noticable effect is the system stops after issuing:

	Loading crashdump kernel...

to the system console.

The tested as working solution I came up with was to add wfe() to
these infinite loops thusly:

	while (1) {
		cpu_relax();
		wfe();
	}

which, without 754327 builds to:

1:	wfe
	b	1b

or with 754327 is enabled:

1:	dmb
	wfe
	b	1b

Adding "wfe" does two things depending on the environment we're running
under:
- where we're running on bare metal, and the processor implements
  "wfe", it stops us spinning endlessly in a loop where we're never
  going to do any useful work.
- if we're running in a VM, it allows the CPU to be given back to the
  hypervisor and rescheduled for other purposes (maybe a different VM)
  rather than wasting CPU cycles inside a crashed VM.

However, in light of erratum 794072, Will Deacon wanted to see 10 nops
as well - which is reasonable to cover the case where we have erratum
754327 enabled _and_ we have a processor that doesn't implement the
wfe hint.

So, we now end up with:

1:      wfe
        b       1b

when erratum 754327 is disabled, or:

1:      dmb
        nop
        nop
        nop
        nop
        nop
        nop
        nop
        nop
        nop
        nop
        wfe
        b       1b

when erratum 754327 is enabled.  We also get the dmb + 10 nop
sequence elsewhere in the kernel, in terminating loops.

This is reasonable - it means we get the workaround for erratum
794072 when erratum 754327 is enabled, but still relinquish the dead
processor - either by placing it in a lower power mode when wfe is
implemented as such or by returning it to the hypervisior, or in the
case where wfe is a no-op, we use the workaround specified in erratum
794072 to avoid the problem.

These as two entirely orthogonal problems - the 10 nops addresses
erratum 794072, and the wfe is an optimisation that makes the system
more efficient when crashed either in terms of power consumption or
by allowing the host/other VMs to make use of the CPU.

I don't see any reason not to use kexec() inside a VM - it has the
potential to provide automated recovery from a failure of the VMs
kernel with the opportunity for saving a crashdump of the failure.
A panic() with a reboot timeout won't do that, and reading the
libvirt documentation, setting on_reboot to "preserve" won't either
(the documentation states "The preserve action for an on_reboot event
is treated as a destroy".)  Surely it has to be a good thing to
avoiding having CPUs spinning inside a VM that is doing no useful
work.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:52 +02:00
Nathan Chancellor
b67ef52116 ARM: 8833/1: Ensure that NEON code always compiles with Clang
[ Upstream commit de9c0d49d85dc563549972edc5589d195cd5e859 ]

While building arm32 allyesconfig, I ran into the following errors:

  arch/arm/lib/xor-neon.c:17:2: error: You should compile this file with
  '-mfloat-abi=softfp -mfpu=neon'

  In file included from lib/raid6/neon1.c:27:
  /home/nathan/cbl/prebuilt/lib/clang/8.0.0/include/arm_neon.h:28:2:
  error: "NEON support not enabled"

Building V=1 showed NEON_FLAGS getting passed along to Clang but
__ARM_NEON__ was not getting defined. Ultimately, it boils down to Clang
only defining __ARM_NEON__ when targeting armv7, rather than armv6k,
which is the '-march' value for allyesconfig.

>From lib/Basic/Targets/ARM.cpp in the Clang source:

  // This only gets set when Neon instructions are actually available, unlike
  // the VFP define, hence the soft float and arch check. This is subtly
  // different from gcc, we follow the intent which was that it should be set
  // when Neon instructions are actually available.
  if ((FPU & NeonFPU) && !SoftFloat && ArchVersion >= 7) {
    Builder.defineMacro("__ARM_NEON", "1");
    Builder.defineMacro("__ARM_NEON__");
    // current AArch32 NEON implementations do not support double-precision
    // floating-point even when it is present in VFP.
    Builder.defineMacro("__ARM_NEON_FP",
                        "0x" + Twine::utohexstr(HW_FP & ~HW_FP_DP));
  }

Ard Biesheuvel recommended explicitly adding '-march=armv7-a' at the
beginning of the NEON_FLAGS definitions so that __ARM_NEON__ always gets
definined by Clang. This doesn't functionally change anything because
that code will only run where NEON is supported, which is implicitly
armv7.

Link: https://github.com/ClangBuiltLinux/linux/issues/287

Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:51 +02:00
Sebastian Andrzej Siewior
1c2bfc4636 ARM: 8840/1: use a raw_spinlock_t in unwind
[ Upstream commit 74ffe79ae538283bbf7c155e62339f1e5c87b55a ]

Mostly unwind is done with irqs enabled however SLUB may call it with
irqs disabled while creating a new SLUB cache.

I had system freeze while loading a module which called
kmem_cache_create() on init. That means SLUB's __slab_alloc() disabled
interrupts and then

->new_slab_objects()
 ->new_slab()
  ->setup_object()
   ->setup_object_debug()
    ->init_tracking()
     ->set_track()
      ->save_stack_trace()
       ->save_stack_trace_tsk()
        ->walk_stackframe()
         ->unwind_frame()
          ->unwind_find_idx()
           =>spin_lock_irqsave(&unwind_lock);

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:50 +02:00
Masahiro Yamada
09f4e69e09 h8300: use cc-cross-prefix instead of hardcoding h8300-unknown-linux-
[ Upstream commit fc2b47b55f17fd996f7a01975ce1c33c2f2513f6 ]

It believe it is a bad idea to hardcode a specific compiler prefix
that may or may not be installed on a user's system. It is annoying
when testing features that should not require compilers at all.

For example, mrproper, headers_install, etc. should work without
any compiler.

They look like follows on my machine.

$ make ARCH=h8300 mrproper
./scripts/gcc-version.sh: line 26: h8300-unknown-linux-gcc: command not found
./scripts/gcc-version.sh: line 27: h8300-unknown-linux-gcc: command not found
make: h8300-unknown-linux-gcc: Command not found
make: h8300-unknown-linux-gcc: Command not found
  [ a bunch of the same error messages continue ]

$ make ARCH=h8300 headers_install
./scripts/gcc-version.sh: line 26: h8300-unknown-linux-gcc: command not found
./scripts/gcc-version.sh: line 27: h8300-unknown-linux-gcc: command not found
make: h8300-unknown-linux-gcc: Command not found
  HOSTCC  scripts/basic/fixdep
make: h8300-unknown-linux-gcc: Command not found
  WRAP    arch/h8300/include/generated/uapi/asm/kvm_para.h
  [ snip ]

The solution is to delete this line, or to use cc-cross-prefix like
some architectures do. I chose the latter as a moderate fixup.

I added an alternative 'h8300-linux-' because it is available at:

https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/8.1.0/

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:33:48 +02:00
Will Deacon
20df60004a arm64: debug: Ensure debug handlers check triggering exception level
commit 6bd288569b50bc89fa5513031086746968f585cb upstream.

Debug exception handlers may be called for exceptions generated both by
user and kernel code. In many cases, this is checked explicitly, but
in other cases things either happen to work by happy accident or they
go slightly wrong. For example, executing 'brk #4' from userspace will
enter the kprobes code and be ignored, but the instruction will be
retried forever in userspace instead of delivering a SIGTRAP.

Fix this issue in the most stable-friendly fashion by simply adding
explicit checks of the triggering exception level to all of our debug
exception handlers.

Cc: <stable@vger.kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:47 +02:00
Will Deacon
a930f8ce20 arm64: debug: Don't propagate UNKNOWN FAR into si_code for debug signals
commit b9a4b9d084d978f80eb9210727c81804588b42ff upstream.

FAR_EL1 is UNKNOWN for all debug exceptions other than those caused by
taking a hardware watchpoint. Unfortunately, if a debug handler returns
a non-zero value, then we will propagate the UNKNOWN FAR value to
userspace via the si_addr field of the SIGTRAP siginfo_t.

Instead, let's set si_addr to take on the PC of the faulting instruction,
which we have available in the current pt_regs.

Cc: <stable@vger.kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:33:47 +02:00
Eric Biggers
455b9a675e arm64: support keyctl() system call in 32-bit mode
[ Upstream commit 5c2a625937ba49bc691089370638223d310cda9a ]

As is the case for a number of other architectures that have a 32-bit
compat mode, enable KEYS_COMPAT if both COMPAT and KEYS are enabled.
This allows AArch32 programs to use the keyctl() system call when
running on an AArch64 kernel.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:29 +02:00
Thomas Gleixner
5ce6e5bd23 x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y
commit bebd024e4815b1a170fcd21ead9c2222b23ce9e6 upstream.

The SMT disable 'nosmt' command line argument is not working properly when
CONFIG_HOTPLUG_CPU is disabled. The teardown of the sibling CPUs which are
required to be brought up due to the MCE issues, cannot work. The CPUs are
then kept in a half dead state.

As the 'nosmt' functionality has become popular due to the speculative
hardware vulnerabilities, the half torn down state is not a proper solution
to the problem.

Enforce CONFIG_HOTPLUG_CPU=y when SMP is enabled so the full operation is
possible.

Reported-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Rik van Riel <riel@surriel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Micheal Kelley <michael.h.kelley@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190326163811.598166056@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:28 +02:00
Kohji Okuno
ed2f3c82b0 ARM: imx6q: cpuidle: fix bug that CPU might not wake up at expected time
commit 91740fc8242b4f260cfa4d4536d8551804777fae upstream.

In the current cpuidle implementation for i.MX6q, the CPU that sets
'WAIT_UNCLOCKED' and the CPU that returns to 'WAIT_CLOCKED' are always
the same. While the CPU that sets 'WAIT_UNCLOCKED' is in IDLE state of
"WAIT", if the other CPU wakes up and enters IDLE state of "WFI"
istead of "WAIT", this CPU can not wake up at expired time.
 Because, in the case of "WFI", the CPU must be waked up by the local
timer interrupt. But, while 'WAIT_UNCLOCKED' is set, the local timer
is stopped, when all CPUs execute "wfi" instruction. As a result, the
local timer interrupt is not fired.
 In this situation, this CPU will wake up by IRQ different from local
timer. (e.g. broacast timer)

So, this fix changes CPU to return to 'WAIT_CLOCKED'.

Signed-off-by: Kohji Okuno <okuno.kohji@jp.panasonic.com>
Fixes: e5f9dec8ff ("ARM: imx6q: support WAIT mode using cpuidle")
Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:26 +02:00
Ezequiel Garcia
c89eceddfa arm64: kconfig: drop CONFIG_RTC_LIB dependency
[ Upstream commit 99a507771fa57238dc7ffe674ae06090333d02c9 ]

The rtc-lib dependency is not required, and seems it was just
copy-pasted from ARM's Kconfig. If platform requires rtc-lib,
they should select it individually.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:24 +02:00
James Morse
60e4a50d33 arm64: kernel: Include _AC definition in page.h
[ Upstream commit 812264550dcba6cdbe84bfac2f27e7d23b5b8733 ]

page.h uses '_AC' in the definition of PAGE_SIZE, but doesn't include
linux/const.h where this is defined. This produces build warnings when only
asm/page.h is included by asm code.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:23 +02:00
Ard Biesheuvel
08d870c51e arm64/kernel: fix incorrect EL0 check in inv_entry macro
[ Upstream commit b660950c60a7278f9d8deb7c32a162031207c758 ]

The implementation of macro inv_entry refers to its 'el' argument without
the required leading backslash, which results in an undefined symbol
'el' to be passed into the kernel_entry macro rather than the index of
the exception level as intended.

This undefined symbol strangely enough does not result in build failures,
although it is visible in vmlinux:

     $ nm -n vmlinux |head
                      U el
     0000000000000000 A _kernel_flags_le_hi32
     0000000000000000 A _kernel_offset_le_hi32
     0000000000000000 A _kernel_size_le_hi32
     000000000000000a A _kernel_flags_le_lo32
     .....

However, it does result in incorrect code being generated for invalid
exceptions taken from EL0, since the argument check in kernel_entry
assumes EL1 if its argument does not equal '0'.

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>
2019-04-03 06:23:23 +02:00
Lorenzo Pieralisi
823e262919 ARM: 8510/1: rework ARM_CPU_SUSPEND dependencies
[ Upstream commit 1b9bdf5c1661873a10e193b8cbb803a87fe5c4a1 ]

The code enabled by the ARM_CPU_SUSPEND config option is used by
kernel subsystems for purposes that go beyond system suspend so its
config entry should be augmented to take more default options into
account and avoid forcing its selection to prevent dependencies
override.

To achieve this goal, this patch reworks the ARM_CPU_SUSPEND config
entry and updates its default config value (by adding the BL_SWITCHER
option to it) and its dependencies (ARCH_SUSPEND_POSSIBLE), so that the
symbol is still selected by default by the subsystems requiring it and
at the same time enforcing the dependencies correctly.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:23 +02:00
Ard Biesheuvel
b6496f00a2 arm64: hide __efistub_ aliases from kallsyms
[ Upstream commit 75feee3d9d51775072d3a04f47d4a439a4c4590e ]

Commit e8f3010f73 ("arm64/efi: isolate EFI stub from the kernel
proper") isolated the EFI stub code from the kernel proper by prefixing
all of its symbols with __efistub_, and selectively allowing access to
core kernel symbols from the stub by emitting __efistub_ aliases for
functions and variables that the stub can access legally.

As an unintended side effect, these aliases are emitted into the
kallsyms symbol table, which means they may turn up in backtraces,
e.g.,

  ...
  PC is at __efistub_memset+0x108/0x200
  LR is at fixup_init+0x3c/0x48
  ...
  [<ffffff8008328608>] __efistub_memset+0x108/0x200
  [<ffffff8008094dcc>] free_initmem+0x2c/0x40
  [<ffffff8008645198>] kernel_init+0x20/0xe0
  [<ffffff8008085cd0>] ret_from_fork+0x10/0x40

The backtrace in question has nothing to do with the EFI stub, but
simply returns one of the several aliases of memset() that have been
recorded in the kallsyms table. This is undesirable, since it may
suggest to people who are not aware of this that the issue they are
seeing is somehow EFI related.

So hide the __efistub_ aliases from kallsyms, by emitting them as
absolute linker symbols explicitly. The distinction between those
and section relative symbols is completely irrelevant to these
definitions, and to the final link we are performing when these
definitions are being taken into account (the distinction is only
relevant to symbols defined inside a section definition when performing
a partial link), and so the resulting values are identical to the
original ones. Since absolute symbols are ignored by kallsyms, this
will result in these values to be omitted from its symbol table.

After this patch, the backtrace generated from the same address looks
like this:
  ...
  PC is at __memset+0x108/0x200
  LR is at fixup_init+0x3c/0x48
  ...
  [<ffffff8008328608>] __memset+0x108/0x200
  [<ffffff8008094dcc>] free_initmem+0x2c/0x40
  [<ffffff8008645198>] kernel_init+0x20/0xe0
  [<ffffff8008085cd0>] ret_from_fork+0x10/0x40

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:21 +02:00
Jungseung Lee
7276c3fbd3 ARM: 8494/1: mm: Enable PXN when running non-LPAE kernel on LPAE processor
[ Upstream commit ad84f56bf6d620fe6ed4d57ce6ec9945684d7f35 ]

The VMSA field of MMFR0 (bottom 4 bits) is incremented for each
added feature.  PXN is supported if the value is >= 4 and LPAE
is supported if it is >= 5.

In case a kernel with CONFIG_ARM_LPAE disabled is used on a
processor that supports LPAE, we can still use PXN in short
descriptors.  So check for >= 4 not == 4.

Signed-off-by: Jungseung Lee <js07.lee@samsung.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:20 +02:00
Arnd Bergmann
717da8c75b ARM: 8458/1: bL_switcher: add GIC dependency
[ Upstream commit 6c044fecdf78be3fda159a5036bb33700cdd5e59 ]

It is not possible to build the bL_switcher code if the GIC
driver is disabled, because it relies on calling into some
gic specific interfaces, and that would result in this build
error:

arch/arm/common/built-in.o: In function `bL_switch_to':
:(.text+0x1230): undefined reference to `gic_get_sgir_physaddr'
:(.text+0x1244): undefined reference to `gic_send_sgi'
:(.text+0x1268): undefined reference to `gic_migrate_target'
arch/arm/common/built-in.o: In function `bL_switcher_enable.part.4':
:(.text.unlikely+0x2f8): undefined reference to `gic_get_cpu_id'

This adds a Kconfig dependency to ensure we only build the big-little
switcher if the GIC driver is present as well.

Almost all ARMv7 platforms come with a GIC anyway, but it is possible
to build a kernel that disables all platforms.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:20 +02:00
Yury Norov
599dcbf7e8 arm64: fix COMPAT_SHMLBA definition for large pages
[ Upstream commit b9b7aebb42d1b1392f3111de61136bb6cf3aae3f ]

ARM glibc uses (4 * __getpagesize()) for SHMLBA, which is correct for
4KB pages and works fine for 64KB pages, but the kernel uses a hardcoded
16KB that is too small for 64KB page based kernels. This changes the
definition to what user space sees when using 64KB pages.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-03 06:23:20 +02:00
Qiao Zhou
e86206bd87 arm64: traps: disable irq in die()
commit 6f44a0bacb79a03972c83759711832b382b1b8ac upstream.

In current die(), the irq is disabled for __die() handle, not
including the possible panic() handling. Since the log in __die()
can take several hundreds ms, new irq might come and interrupt
current die().

If the process calling die() holds some critical resource, and some
other process scheduled later also needs it, then it would deadlock.
The first panic will not be executed.

So here disable irq for the whole flow of die().

Signed-off-by: Qiao Zhou <qiaozhou@asrmicro.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:19 +02:00
James Morse
aa8b7ed216 arm64: mm: Add trace_irqflags annotations to do_debug_exception()
commit 6afedcd23cfd7ac56c011069e4a8db37b46e4623 upstream.

With CONFIG_PROVE_LOCKING, CONFIG_DEBUG_LOCKDEP and CONFIG_TRACE_IRQFLAGS
enabled, lockdep will compare current->hardirqs_enabled with the flags from
local_irq_save().

When a debug exception occurs, interrupts are disabled in entry.S, but
lockdep isn't told, resulting in:
DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
------------[ cut here ]------------
WARNING: at ../kernel/locking/lockdep.c:3523
Modules linked in:
CPU: 3 PID: 1752 Comm: perf Not tainted 4.5.0-rc4+ #2204
Hardware name: ARM Juno development board (r1) (DT)
task: ffffffc974868000 ti: ffffffc975f40000 task.ti: ffffffc975f40000
PC is at check_flags.part.35+0x17c/0x184
LR is at check_flags.part.35+0x17c/0x184
pc : [<ffffff80080fc93c>] lr : [<ffffff80080fc93c>] pstate: 600003c5
[...]
---[ end trace 74631f9305ef5020 ]---
Call trace:
[<ffffff80080fc93c>] check_flags.part.35+0x17c/0x184
[<ffffff80080ffe30>] lock_acquire+0xa8/0xc4
[<ffffff8008093038>] breakpoint_handler+0x118/0x288
[<ffffff8008082434>] do_debug_exception+0x3c/0xa8
[<ffffff80080854b4>] el1_dbg+0x18/0x6c
[<ffffff80081e82f4>] do_filp_open+0x64/0xdc
[<ffffff80081d6e60>] do_sys_open+0x140/0x204
[<ffffff80081d6f58>] SyS_openat+0x10/0x18
[<ffffff8008085d30>] el0_svc_naked+0x24/0x28
possible reason: unannotated irqs-off.
irq event stamp: 65857
hardirqs last  enabled at (65857): [<ffffff80081fb1c0>] lookup_mnt+0xf4/0x1b4
hardirqs last disabled at (65856): [<ffffff80081fb188>] lookup_mnt+0xbc/0x1b4
softirqs last  enabled at (65790): [<ffffff80080bdca4>] __do_softirq+0x1f8/0x290
softirqs last disabled at (65757): [<ffffff80080be038>] irq_exit+0x9c/0xd0

This patch adds the annotations to do_debug_exception(), while trying not
to call trace_hardirqs_off() if el1_dbg() interrupted a task that already
had irqs disabled.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:18 +02:00
Archer Yan
8df0d57e5c MIPS: Fix kernel crash for R6 in jump label branch function
commit 47c25036b60f27b86ab44b66a8861bcf81cde39b upstream.

Insert Branch instruction instead of NOP to make sure assembler don't
patch code in forbidden slot. In jump label function, it might
be possible to patch Control Transfer Instructions(CTIs) into
forbidden slot, which will generate Reserved Instruction exception
in MIPS release 6.

Signed-off-by: Archer Yan <ayan@wavecomp.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
[paul.burton@mips.com:
  - Add MIPS prefix to subject.
  - Mark for stable from v4.0, which introduced r6 support, onwards.]
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:14 +02:00
Yifeng Li
5c06f24095 mips: loongson64: lemote-2f: Add IRQF_NO_SUSPEND to "cascade" irqaction.
commit 5f5f67da9781770df0403269bc57d7aae608fecd upstream.

Timekeeping IRQs from CS5536 MFGPT are routed to i8259, which then
triggers the "cascade" IRQ on MIPS CPU. Without IRQF_NO_SUSPEND in
cascade_irqaction, MFGPT interrupts will be masked in suspend mode,
and the machine would be unable to resume once suspended.

Previously, MIPS IRQs were not disabled properly, so the original
code appeared to work. Commit a3e6c1eff5 ("MIPS: IRQ: Fix disable_irq on
CPU IRQs") uncovers the bug. To fix it, add IRQF_NO_SUSPEND to
cascade_irqaction.

This commit is functionally identical to 0add9c2f1c ("MIPS:
Loongson-3: Add IRQF_NO_SUSPEND to Cascade irqaction"), but it forgot
to apply the same fix to Loongson2.

Signed-off-by: Yifeng Li <tomli@tomli.me>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # v3.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:23:14 +02:00
Wanpeng Li
5d8f03acc1 KVM: X86: Fix residual mmio emulation request to userspace
commit bbeac2830f4de270bb48141681cb730aadf8dce1 upstream.

Reported by syzkaller:

The kvm-intel.unrestricted_guest=0

   WARNING: CPU: 5 PID: 1014 at /home/kernel/data/kvm/arch/x86/kvm//x86.c:7227 kvm_arch_vcpu_ioctl_run+0x38b/0x1be0 [kvm]
   CPU: 5 PID: 1014 Comm: warn_test Tainted: G        W  OE   4.13.0-rc3+ #8
   RIP: 0010:kvm_arch_vcpu_ioctl_run+0x38b/0x1be0 [kvm]
   Call Trace:
    ? put_pid+0x3a/0x50
    ? rcu_read_lock_sched_held+0x79/0x80
    ? kmem_cache_free+0x2f2/0x350
    kvm_vcpu_ioctl+0x340/0x700 [kvm]
    ? kvm_vcpu_ioctl+0x340/0x700 [kvm]
    ? __fget+0xfc/0x210
    do_vfs_ioctl+0xa4/0x6a0
    ? __fget+0x11d/0x210
    SyS_ioctl+0x79/0x90
    entry_SYSCALL_64_fastpath+0x23/0xc2
    ? __this_cpu_preempt_check+0x13/0x20

The syszkaller folks reported a residual mmio emulation request to userspace
due to vm86 fails to emulate inject real mode interrupt(fails to read CS) and
incurs a triple fault. The vCPU returns to userspace with vcpu->mmio_needed == true
and KVM_EXIT_SHUTDOWN exit reason. However, the syszkaller testcase constructs
several threads to launch the same vCPU, the thread which lauch this vCPU after
the thread whichs get the vcpu->mmio_needed == true and KVM_EXIT_SHUTDOWN will
trigger the warning.

   #define _GNU_SOURCE
   #include <pthread.h>
   #include <stdio.h>
   #include <stdlib.h>
   #include <string.h>
   #include <sys/wait.h>
   #include <sys/types.h>
   #include <sys/stat.h>
   #include <sys/mman.h>
   #include <fcntl.h>
   #include <unistd.h>
   #include <linux/kvm.h>
   #include <stdio.h>

   int kvmcpu;
   struct kvm_run *run;

   void* thr(void* arg)
   {
     int res;
     res = ioctl(kvmcpu, KVM_RUN, 0);
     printf("ret1=%d exit_reason=%d suberror=%d\n",
         res, run->exit_reason, run->internal.suberror);
     return 0;
   }

   void test()
   {
     int i, kvm, kvmvm;
     pthread_t th[4];

     kvm = open("/dev/kvm", O_RDWR);
     kvmvm = ioctl(kvm, KVM_CREATE_VM, 0);
     kvmcpu = ioctl(kvmvm, KVM_CREATE_VCPU, 0);
     run = (struct kvm_run*)mmap(0, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, kvmcpu, 0);
     srand(getpid());
     for (i = 0; i < 4; i++) {
       pthread_create(&th[i], 0, thr, 0);
       usleep(rand() % 10000);
     }
     for (i = 0; i < 4; i++)
       pthread_join(th[i], 0);
   }

   int main()
   {
     for (;;) {
       int pid = fork();
       if (pid < 0)
         exit(1);
       if (pid == 0) {
         test();
         exit(0);
       }
       int status;
       while (waitpid(pid, &status, __WALL) != pid) {}
     }
     return 0;
   }

This patch fixes it by resetting the vcpu->mmio_needed once we receive
the triple fault to avoid the residue.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Zubin Mithra <zsm@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:40 +01:00
Sean Christopherson
8c7543e3b8 KVM: nVMX: Ignore limit checks on VMX instructions using flat segments
commit 34333cc6c2cb021662fd32e24e618d1b86de95bf upstream.

Regarding segments with a limit==0xffffffff, the SDM officially states:

    When the effective limit is FFFFFFFFH (4 GBytes), these accesses may
    or may not cause the indicated exceptions.  Behavior is
    implementation-specific and may vary from one execution to another.

In practice, all CPUs that support VMX ignore limit checks for "flat
segments", i.e. an expand-up data or code segment with base=0 and
limit=0xffffffff.  This is subtly different than wrapping the effective
address calculation based on the address size, as the flat segment
behavior also applies to accesses that would wrap the 4g boundary, e.g.
a 4-byte access starting at 0xffffffff will access linear addresses
0xffffffff, 0x0, 0x1 and 0x2.

Fixes: f9eb4af67c ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:40 +01:00
Sean Christopherson
2866808ffc KVM: nVMX: Sign extend displacements of VMX instr's mem operands
commit 946c522b603f281195af1df91837a1d4d1eb3bc9 upstream.

The VMCS.EXIT_QUALIFCATION field reports the displacements of memory
operands for various instructions, including VMX instructions, as a
naturally sized unsigned value, but masks the value by the addr size,
e.g. given a ModRM encoded as -0x28(%ebp), the -0x28 displacement is
reported as 0xffffffd8 for a 32-bit address size.  Despite some weird
wording regarding sign extension, the SDM explicitly states that bits
beyond the instructions address size are undefined:

    In all cases, bits of this field beyond the instruction’s address
    size are undefined.

Failure to sign extend the displacement results in KVM incorrectly
treating a negative displacement as a large positive displacement when
the address size of the VMX instruction is smaller than KVM's native
size, e.g. a 32-bit address size on a 64-bit KVM.

The very original decoding, added by commit 064aea7747 ("KVM: nVMX:
Decoding memory operands of VMX instructions"), sort of modeled sign
extension by truncating the final virtual/linear address for a 32-bit
address size.  I.e. it messed up the effective address but made it work
by adjusting the final address.

When segmentation checks were added, the truncation logic was kept
as-is and no sign extension logic was introduced.  In other words, it
kept calculating the wrong effective address while mostly generating
the correct virtual/linear address.  As the effective address is what's
used in the segment limit checks, this results in KVM incorreclty
injecting #GP/#SS faults due to non-existent segment violations when
a nested VMM uses negative displacements with an address size smaller
than KVM's native address size.

Using the -0x28(%ebp) example, an EBP value of 0x1000 will result in
KVM using 0x100000fd8 as the effective address when checking for a
segment limit violation.  This causes a 100% failure rate when running
a 32-bit KVM build as L1 on top of a 64-bit KVM L0.

Fixes: f9eb4af67c ("KVM: nVMX: VMX instructions: add checks for #GP/#SS exceptions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:40 +01:00
Gustavo A. R. Silva
fd2ebccb58 ARM: s3c24xx: Fix boolean expressions in osiris_dvs_notify
commit e2477233145f2156434afb799583bccd878f3e9f upstream.

Fix boolean expressions by using logical AND operator '&&' instead of
bitwise operator '&'.

This issue was detected with the help of Coccinelle.

Fixes: 4fa084af28 ("ARM: OSIRIS: DVS (Dynamic Voltage Scaling) supoort.")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
[krzk: Fix -Wparentheses warning]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:38 +01:00
Christophe Leroy
7ea0c2f978 powerpc/83xx: Also save/restore SPRG4-7 during suspend
commit 36da5ff0bea2dc67298150ead8d8471575c54c7d upstream.

The 83xx has 8 SPRG registers and uses at least SPRG4
for DTLB handling LRU.

Fixes: 2319f12395 ("powerpc/mm: e300c2/c3/c4 TLB errata workaround")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:38 +01:00
Jordan Niethe
d9fbe055bc powerpc/powernv: Make opal log only readable by root
commit 7b62f9bd2246b7d3d086e571397c14ba52645ef1 upstream.

Currently the opal log is globally readable. It is kernel policy to
limit the visibility of physical addresses / kernel pointers to root.
Given this and the fact the opal log may contain this information it
would be better to limit the readability to root.

Fixes: bfc36894a4 ("powerpc/powernv: Add OPAL message log interface")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Stewart Smith <stewart@linux.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:38 +01:00
Christophe Leroy
aa3995f04e powerpc/wii: properly disable use of BATs when requested.
commit 6d183ca8baec983dc4208ca45ece3c36763df912 upstream.

'nobats' kernel parameter or some options like CONFIG_DEBUG_PAGEALLOC
deny the use of BATS for mapping memory.

This patch makes sure that the specific wii RAM mapping function
takes it into account as well.

Fixes: de32400dd2 ("wii: use both mem1 and mem2 as ram")
Cc: stable@vger.kernel.org
Reviewed-by: Jonathan Neuschafer <j.neuschaefer@gmx.net>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:38 +01:00
Christophe Leroy
788b1a98f4 powerpc/32: Clear on-stack exception marker upon exception return
commit 9580b71b5a7863c24a9bd18bcd2ad759b86b1eff upstream.

Clear the on-stack STACK_FRAME_REGS_MARKER on exception exit in order
to avoid confusing stacktrace like the one below.

  Call Trace:
  [c0e9dca0] [c01c42a0] print_address_description+0x64/0x2bc (unreliable)
  [c0e9dcd0] [c01c4684] kasan_report+0xfc/0x180
  [c0e9dd10] [c0895130] memchr+0x24/0x74
  [c0e9dd30] [c00a9e38] msg_print_text+0x124/0x574
  [c0e9dde0] [c00ab710] console_unlock+0x114/0x4f8
  [c0e9de40] [c00adc60] vprintk_emit+0x188/0x1c4
  --- interrupt: c0e9df00 at 0x400f330
      LR = init_stack+0x1f00/0x2000
  [c0e9de80] [c00ae3c4] printk+0xa8/0xcc (unreliable)
  [c0e9df20] [c0c27e44] early_irq_init+0x38/0x108
  [c0e9df50] [c0c15434] start_kernel+0x310/0x488
  [c0e9dff0] [00003484] 0x3484

With this patch the trace becomes:

  Call Trace:
  [c0e9dca0] [c01c42c0] print_address_description+0x64/0x2bc (unreliable)
  [c0e9dcd0] [c01c46a4] kasan_report+0xfc/0x180
  [c0e9dd10] [c0895150] memchr+0x24/0x74
  [c0e9dd30] [c00a9e58] msg_print_text+0x124/0x574
  [c0e9dde0] [c00ab730] console_unlock+0x114/0x4f8
  [c0e9de40] [c00adc80] vprintk_emit+0x188/0x1c4
  [c0e9de80] [c00ae3e4] printk+0xa8/0xcc
  [c0e9df20] [c0c27e44] early_irq_init+0x38/0x108
  [c0e9df50] [c0c15434] start_kernel+0x310/0x488
  [c0e9dff0] [00003484] 0x3484

Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:37 +01:00
Finn Thain
22058c290c m68k: Add -ffreestanding to CFLAGS
commit 28713169d879b67be2ef2f84dcf54905de238294 upstream.

This patch fixes a build failure when using GCC 8.1:

/usr/bin/ld: block/partitions/ldm.o: in function `ldm_parse_tocblock':
block/partitions/ldm.c:153: undefined reference to `strcmp'

This is caused by a new optimization which effectively replaces a
strncmp() call with a strcmp() call. This affects a number of strncmp()
call sites in the kernel.

The entire class of optimizations is avoided with -fno-builtin, which
gets enabled by -ffreestanding. This may avoid possible future build
failures in case new optimizations appear in future compilers.

I haven't done any performance measurements with this patch but I did
count the function calls in a defconfig build. For example, there are now
23 more sprintf() calls and 39 fewer strcpy() calls. The effect on the
other libc functions is smaller.

If this harms performance we can tackle that regression by optimizing
the call sites, ideally using semantic patches. That way, clang and ICC
builds might benfit too.

Cc: stable@vger.kernel.org
Reference: https://marc.info/?l=linux-m68k&m=154514816222244&w=2
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:36 +01:00
Ard Biesheuvel
a2ef87f9d2 crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling
commit eaf46edf6ea89675bd36245369c8de5063a0272c upstream.

The NEON MAC calculation routine fails to handle the case correctly
where there is some data in the buffer, and the input fills it up
exactly. In this case, we enter the loop at the end with w8 == 0,
while a negative value is assumed, and so the loop carries on until
the increment of the 32-bit counter wraps around, which is quite
obviously wrong.

So omit the loop altogether in this case, and exit right away.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: a3fd82105b ("arm64/crypto: AES in CCM mode using ARMv8 Crypto ...")
Cc: stable@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 08:44:34 +01:00