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Merge 4.4.129 into android-4.4
Changes in 4.4.129
media: v4l2-compat-ioctl32: don't oops on overlay
parisc: Fix out of array access in match_pci_device()
perf intel-pt: Fix overlap detection to identify consecutive buffers correctly
perf intel-pt: Fix sync_switch
perf intel-pt: Fix error recovery from missing TIP packet
perf intel-pt: Fix timestamp following overflow
radeon: hide pointless #warning when compile testing
Revert "perf tests: Decompress kernel module before objdump"
block/loop: fix deadlock after loop_set_status
s390/qdio: don't retry EQBS after CCQ 96
s390/qdio: don't merge ERROR output buffers
s390/ipl: ensure loadparm valid flag is set
getname_kernel() needs to make sure that ->name != ->iname in long case
rtl8187: Fix NULL pointer dereference in priv->conf_mutex
hwmon: (ina2xx) Fix access to uninitialized mutex
cdc_ether: flag the Cinterion AHS8 modem by gemalto as WWAN
slip: Check if rstate is initialized before uncompressing
lan78xx: Correctly indicate invalid OTP
x86/hweight: Get rid of the special calling convention
x86/hweight: Don't clobber %rdi
tty: make n_tty_read() always abort if hangup is in progress
ubifs: Check ubifs_wbuf_sync() return code
ubi: fastmap: Don't flush fastmap work on detach
ubi: Fix error for write access
ubi: Reject MLC NAND
fs/reiserfs/journal.c: add missing resierfs_warning() arg
resource: fix integer overflow at reallocation
ipc/shm: fix use-after-free of shm file via remap_file_pages()
mm, slab: reschedule cache_reap() on the same CPU
usb: musb: gadget: misplaced out of bounds check
ARM: dts: at91: at91sam9g25: fix mux-mask pinctrl property
ARM: dts: at91: sama5d4: fix pinctrl compatible string
xen-netfront: Fix hang on device removal
regmap: Fix reversed bounds check in regmap_raw_write()
ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E
ACPI / hotplug / PCI: Check presence of slot itself in get_slot_status()
USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw
usb: dwc3: pci: Properly cleanup resource
HID: i2c-hid: fix size check and type usage
powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write()
powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently
powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops
powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops
HID: Fix hid_report_len usage
HID: core: Fix size as type u32
ASoC: ssm2602: Replace reg_default_raw with reg_default
thunderbolt: Resume control channel after hibernation image is created
random: use a tighter cap in credit_entropy_bits_safe()
jbd2: if the journal is aborted then don't allow update of the log tail
ext4: don't update checksum of new initialized bitmaps
ext4: fail ext4_iget for root directory if unallocated
RDMA/ucma: Don't allow setting RDMA_OPTION_IB_PATH without an RDMA device
ALSA: pcm: Fix UAF at PCM release via PCM timer access
IB/srp: Fix srp_abort()
IB/srp: Fix completion vector assignment algorithm
dmaengine: at_xdmac: fix rare residue corruption
um: Use POSIX ucontext_t instead of struct ucontext
iommu/vt-d: Fix a potential memory leak
mmc: jz4740: Fix race condition in IRQ mask update
clk: mvebu: armada-38x: add support for 1866MHz variants
clk: mvebu: armada-38x: add support for missing clocks
clk: bcm2835: De-assert/assert PLL reset signal when appropriate
thermal: imx: Fix race condition in imx_thermal_probe()
watchdog: f71808e_wdt: Fix WD_EN register read
ALSA: oss: consolidate kmalloc/memset 0 call to kzalloc
ALSA: pcm: Use ERESTARTSYS instead of EINTR in OSS emulation
ALSA: pcm: Avoid potential races between OSS ioctls and read/write
ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams
ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls
ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation
vfio-pci: Virtualize PCIe & AF FLR
vfio/pci: Virtualize Maximum Payload Size
vfio/pci: Virtualize Maximum Read Request Size
ext4: don't allow r/w mounts if metadata blocks overlap the superblock
drm/radeon: Fix PCIe lane width calculation
ext4: fix crashes in dioread_nolock mode
ext4: fix deadlock between inline_data and ext4_expand_extra_isize_ea()
ALSA: line6: Use correct endpoint type for midi output
ALSA: rawmidi: Fix missing input substream checks in compat ioctls
ALSA: hda - New VIA controller suppor no-snoop path
HID: hidraw: Fix crash on HIDIOCGFEATURE with a destroyed device
MIPS: uaccess: Add micromips clobbers to bzero invocation
MIPS: memset.S: EVA & fault support for small_memset
MIPS: memset.S: Fix return of __clear_user from Lpartial_fixup
MIPS: memset.S: Fix clobber of v1 in last_fixup
powerpc/eeh: Fix enabling bridge MMIO windows
powerpc/lib: Fix off-by-one in alternate feature patching
jffs2_kill_sb(): deal with failed allocations
hypfs_kill_super(): deal with failed allocations
rpc_pipefs: fix double-dput()
Don't leak MNT_INTERNAL away from internal mounts
autofs: mount point create should honour passed in mode
mm: allow GFP_{FS,IO} for page_cache_read page cache allocation
mm/filemap.c: fix NULL pointer in page_cache_tree_insert()
ext4: bugfix for mmaped pages in mpage_release_unused_pages()
fanotify: fix logic of events on child
writeback: safer lock nesting
Linux 4.4.129
Change-Id: I8806d2cc92fe512f27a349e8f630ced0cac9a8d7
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 615b2665fd20c327b631ff1e79426775de748094 upstream.
As found by the ubsan checker, the value of the 'index' variable can be
out of range for the bc[] array:
UBSAN: Undefined behaviour in arch/parisc/kernel/drivers.c:655:21
index 6 is out of range for type 'char [6]'
Backtrace:
[<104fa850>] __ubsan_handle_out_of_bounds+0x68/0x80
[<1019d83c>] check_parent+0xc0/0x170
[<1019d91c>] descend_children+0x30/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019cd54>] parse_tree_node+0x40/0x54
[<1019d86c>] check_parent+0xf0/0x170
[<1019d91c>] descend_children+0x30/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019d938>] descend_children+0x4c/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019cd54>] parse_tree_node+0x40/0x54
[<1019cffc>] hwpath_to_device+0xa4/0xc4
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.4.111 into android-4.4
Changes in 4.4.111
x86/kasan: Write protect kasan zero shadow
kernel/acct.c: fix the acct->needcheck check in check_free_space()
crypto: n2 - cure use after free
crypto: chacha20poly1305 - validate the digest size
crypto: pcrypt - fix freeing pcrypt instances
sunxi-rsb: Include OF based modalias in device uevent
fscache: Fix the default for fscache_maybe_release_page()
kernel: make groups_sort calling a responsibility group_info allocators
kernel/signal.c: protect the traced SIGNAL_UNKILLABLE tasks from SIGKILL
kernel/signal.c: protect the SIGNAL_UNKILLABLE tasks from !sig_kernel_only() signals
kernel/signal.c: remove the no longer needed SIGNAL_UNKILLABLE check in complete_signal()
ARC: uaccess: dont use "l" gcc inline asm constraint modifier
Input: elantech - add new icbody type 15
x86/microcode/AMD: Add support for fam17h microcode loading
parisc: Fix alignment of pa_tlb_lock in assembly on 32-bit SMP kernel
x86/tlb: Drop the _GPL from the cpu_tlbstate export
genksyms: Handle string literals with spaces in reference files
module: keep percpu symbols in module's symtab
module: Issue warnings when tainting kernel
proc: much faster /proc/vmstat
Map the vsyscall page with _PAGE_USER
Fix build error in vma.c
Linux 4.4.111
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 88776c0e70be0290f8357019d844aae15edaa967 upstream.
Qemu for PARISC reported on a 32bit SMP parisc kernel strange failures
about "Not-handled unaligned insn 0x0e8011d6 and 0x0c2011c9."
Those opcodes evaluate to the ldcw() assembly instruction which requires
(on 32bit) an alignment of 16 bytes to ensure atomicity.
As it turns out, qemu is correct and in our assembly code in entry.S and
pacache.S we don't pay attention to the required alignment.
This patch fixes the problem by aligning the lock offset in assembly
code in the same manner as we do in our C-code.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: 64145065
(cherry-picked from be7635e7287e0e8013af3c89a6354a9e0182594c)
Change-Id: Ib321eb9c2b76ef4785cf3fd522169f524348bd9a
Signed-off-by: Paul Lawrence <paullawrence@google.com>
commit 05f016d2ca7a4fab99d5d5472168506ddf95e74f upstream.
As noted by Christoph Biedl, passing a pointer size of 4 in the new CAS
implementation causes a kernel crash. The attached patch corrects the
off by one error in the argument validity check.
In reviewing the code, I noticed that we only perform word operations
with the pointer size argument. The subi instruction intentionally uses
a word condition on 64-bit kernels. Nullification was used instead of a
cmpib instruction as the branch should never be taken. The shlw
pseudo-operation generates a depw,z instruction and it clears the target
before doing a shift left word deposit. Thus, we don't need to clip the
upper 32 bits of this argument on 64-bit kernels.
Tested with a gcc testsuite run with a 64-bit kernel. The gcc atomic
code in libgcc is the only direct user of the new CAS implementation
that I am aware of.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 374b3bf8e8b519f61eb9775888074c6e46b3bf0c upstream.
As discussed on the debian-hppa list, double-wordcompare and exchange
operations fail on 32-bit kernels. Looking at the code, I realized that
the ",ma" completer does the wrong thing in the "ldw,ma 4(%r26), %r29"
instruction. This increments %r26 and causes the following store to
write to the wrong location.
Note by Helge Deller:
The patch applies cleanly to stable kernel series if this upstream
commit is merged in advance:
f4125cfdb300 ("parisc: Avoid trashing sr2 and sr3 in LWS code").
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Tested-by: Christoph Biedl <debian.axhn@manchmal.in-ulm.de>
Fixes: 8920649120 ("parisc: Implement new LWS CAS supporting 64 bit operations.")
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f4125cfdb3008363137f744c101e5d76ead760ba upstream.
There is no need to trash sr2 and sr3 in the Light-weight syscall (LWS). sr2
already points to kernel space (it's zero in userspace, otherwise syscalls
wouldn't work), and since the LWS code is executed in userspace, we can simply
ignore to preload sr3.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b0f94efd5aa8daa8a07d7601714c2573266cd4c9 upstream.
Architectures with a compat syscall table must put compat_sys_keyctl()
in it, not sys_keyctl(). The parisc architecture was not doing this;
fix it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[wt: backport to 4.11: adjust context]
[wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide]
[wt: backport to 4.4: adjust context ; drop ppc hugetlb_radix changes]
Signed-off-by: Willy Tarreau <w@1wt.eu>
[gkh: minor build fixes for 4.4]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 24d0492b7d5d321a9c5846c8c974eba9823ffaa0 upstream.
At bootup we run measurements to calculate the best threshold for when we
should be using full TLB flushes instead of just flushing a specific amount of
TLB entries. This performance test is run over the kernel text segment.
But running this TLB performance test on the kernel text segment turned out to
crash some SMP machines when the kernel text pages were mapped as huge pages.
To avoid those crashes this patch simply skips this test on some SMP machines
and calculates an optimal threshold based on the maximum number of available
TLB entries and number of online CPUs.
On a technical side, this seems to happen:
The TLB measurement code uses flush_tlb_kernel_range() to flush specific TLB
entries with a page size of 4k (pdtlb 0(sr1,addr)). On UP systems this purge
instruction seems to work without problems even if the pages were mapped as
huge pages. But on SMP systems the TLB purge instruction is broadcasted to
other CPUs. Those CPUs then crash the machine because the page size is not as
expected. C8000 machines with PA8800/PA8900 CPUs were not affected by this
problem, because the required cache coherency prohibits to use huge pages at
all. Sadly I didn't found any documentation about this behaviour, so this
finding is purely based on testing with phyiscal SMP machines (A500-44 and
J5000, both were 2-way boxes).
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit febe42964fe182281859b3d43d844bb25ca49367 upstream.
We have four routines in pacache.S that use temporary alias pages:
copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
flush_icache_page_asm(). copy_user_page_asm() and clear_user_page_asm()
don't purge the TLB entry used for the operation.
flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.
Presumably, this was thought to optimize TLB use. However, the
operation is quite heavy weight on PA 1.X processors as we need to take
the TLB lock and a TLB broadcast is sent to all processors.
This patch removes the purges from flush_dcache_page_asm() and
flush_icache_page_asm.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5035b230e7b67ac12691ed3b5495bbb617027b68 upstream.
This is the second issue I noticed in reviewing the parisc TLB code.
The fic instruction may use either the instruction or data TLB in
flushing the instruction cache. Thus, on machines with a split TLB, we
should also flush the data TLB after setting up the temporary alias
registers.
Although this has no functional impact, I changed the pdtlb and pitlb
instructions to consistently use the index register %r0. These
instructions do not support integer displacements.
Tested on rp3440 and c8000.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c0452fb9fb8f49c7d68ab9fa0ad092016be7b45f upstream.
We are still troubled by occasional random segmentation faults and
memory memory corruption on SMP machines. The causes quite a few
package builds to fail on the Debian buildd machines for parisc. When
gcc-6 failed to build three times in a row, I looked again at the TLB
related code. I found a couple of issues. This is the first.
In general, we need to ensure page table updates and corresponding TLB
purges are atomic. The attached patch fixes an instance in pci-dma.c
where the page table update was not guarded by the TLB lock.
Tested on rp3440 and c8000. So far, no further random segmentation
faults have been observed.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6ed518328d0189e0fdf1bb7c73290d546143ea66 upstream.
We have one critical section in the syscall entry path in which we switch from
the userspace stack to kernel stack. In the event of an external interrupt, the
interrupt code distinguishes between those two states by analyzing the value of
sr7. If sr7 is zero, it uses the kernel stack. Therefore it's important, that
the value of sr7 is in sync with the currently enabled stack.
This patch now disables interrupts while executing the critical section. This
prevents the interrupt handler to possibly see an inconsistent state which in
the worst case can lead to crashes.
Interestingly, in the syscall exit path interrupts were already disabled in the
critical section which switches back to the userspace stack.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f8850abb7ba68229838014b3409460e576751c6d upstream.
Architecturally we need to keep __gp below 0x1000000.
But because of ftrace and tracepoint support, the RO_DATA_SECTION now gets much
bigger than it was before. By moving the linkage tables before RO_DATA_SECTION
we can avoid that __gp gets positioned at a too high address.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 690d097c00c88fa9d93d198591e184164b1d8c20 upstream.
Increase the initial kernel default page mapping size for SMP kernels to 32MB
and add a runtime check which panics early if the kernel is bigger than the
initial mapping size.
This fixes boot crashes of 32bit SMP kernels. Due to the introduction of huge
page support in kernel 4.4 and it's required initial kernel layout in memory, a
32bit SMP kernel usually got bigger (in layout, not size) than 16MB.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8b78f260887df532da529f225c49195d18fef36b upstream.
One of the debian buildd servers had this crash in the syslog without
any other information:
Unaligned handler failed, ret = -2
clock_adjtime (pid 22578): Unaligned data reference (code 28)
CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G E 4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000
YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001001111100000001111 Tainted: G E
r00-03 000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
r04-07 00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
r08-11 0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
r12-15 000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
r16-19 0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
r20-23 0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
r24-27 0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
r28-31 0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
sr00-03 0000000001200000 0000000001200000 0000000000000000 0000000001200000
sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
IIR: 0ca0d089 ISR: 0000000001200000 IOR: 00000000fa6f7fff
CPU: 1 CR30: 00000001bde7c000 CR31: ffffffffffffffff
ORIG_R28: 00000002369fe628
IAOQ[0]: compat_get_timex+0x2dc/0x3c0
IAOQ[1]: compat_get_timex+0x2e0/0x3c0
RP(r2): compat_get_timex+0x40/0x3c0
Backtrace:
[<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
[<0000000040205024>] syscall_exit+0x0/0x14
This means the userspace program clock_adjtime called the clock_adjtime()
syscall and then crashed inside the compat_get_timex() function.
Syscalls should never crash programs, but instead return EFAULT.
The IIR register contains the executed instruction, which disassebles
into "ldw 0(sr3,r5),r9".
This load-word instruction is part of __get_user() which tried to read the word
at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in. The
unaligned handler is able to emulate all ldw instructions, but it fails if it
fails to read the source e.g. because of page fault.
The following program reproduces the problem:
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/mman.h>
int main(void) {
/* allocate 8k */
char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
/* free second half (upper 4k) and make it invalid. */
munmap(ptr+4096, 4096);
/* syscall where first int is unaligned and clobbers into invalid memory region */
/* syscall should return EFAULT */
return syscall(__NR_clock_adjtime, 0, ptr+4095);
}
To fix this issue we simply need to check if the faulting instruction address
is in the exception fixup table when the unaligned handler failed. If it
is, call the fixup routine instead of crashing.
While looking at the unaligned handler I found another issue as well: The
target register should not be modified if the handler was unsuccessful.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2ef4dfd9d9f288943e249b78365a69e3ea3ec072 upstream.
Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.
When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ef72f3110d8b19f4c098a0bff7ed7d11945e70c6 upstream.
The kernel module testcase (lib/test_user_copy.c) exhibited a kernel
crash on parisc if the parameters for copy_from_user were reversed
("illegal reversed copy_to_user" testcase).
Fix this potential crash by checking the fault handler if the faulting
address is in the exception table.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e3893027a300927049efc1572f852201eb785142 upstream.
We want to avoid the kernel module loader to create function pointers
for the kernel fixup routines of get_user() and put_user(). Changing
the external reference from function type to int type fixes this.
This unbreaks exception handling for get_user() and put_user() when
called from a kernel module.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 98e8b6c9ac9d1b1e9d1122dfa6783d5d566bb8f7 upstream.
Mike Frysinger reported that his ptrace testcase showed strange
behaviour on parisc: It was not possible to avoid a syscall and the
return value of a syscall couldn't be changed.
To modify a syscall number, we were missing to save the new syscall
number to gr20 which is then picked up later in assembly again.
The effect that the return value couldn't be changed is a side-effect of
another bug in the assembly code. When a process is ptraced, userspace
expects each syscall to report entrance and exit of a syscall. If a
syscall number was given which doesn't exist, we jumped to the normal
syscall exit code instead of informing userspace that the (non-existant)
syscall exits. This unexpected behaviour confuses userspace and thus the
bug was misinterpreted as if we can't change the return value.
This patch fixes both problems and was tested on 64bit kernel with
32bit userspace.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Mike Frysinger <vapier@gentoo.org>
Tested-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On parisc syscalls which are interrupted by signals sometimes failed to
restart and instead returned -ENOSYS which in the worst case lead to
userspace crashes.
A similiar problem existed on MIPS and was fixed by commit e967ef02
("MIPS: Fix restart of indirect syscalls").
On parisc the current syscall restart code assumes that all syscall
callers load the syscall number in the delay slot of the ble
instruction. That's how it is e.g. done in the unistd.h header file:
ble 0x100(%sr2, %r0)
ldi #syscall_nr, %r20
Because of that assumption the current code never restored %r20 before
returning to userspace.
This assumption is at least not true for code which uses the glibc
syscall() function, which instead uses this syntax:
ble 0x100(%sr2, %r0)
copy regX, %r20
where regX depend on how the compiler optimizes the code and register
usage.
This patch fixes this problem by adding code to analyze how the syscall
number is loaded in the delay branch and - if needed - copy the syscall
number to regX prior returning to userspace for the syscall restart.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
There are no callers of pcibios_init_bus(), so remove it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Pull parisc update from Helge Deller:
"This patchset adds Huge Page and HUGETLBFS support for parisc"
Honestly, the hugepage support should have gone through in the merge
window, and is not really an rc-time fix. But it only touches
arch/parisc, and I cannot find it in myself to care. If one of the
three parisc users notices a breakage, I will point at Helge and make
rude farting noises.
* 'parisc-4.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Map kernel text and data on huge pages
parisc: Add Huge Page and HUGETLBFS support
parisc: Use long branch to do_syscall_trace_exit
parisc: Increase initial kernel mapping to 32MB on 64bit kernel
parisc: Initialize the fault vector earlier in the boot process.
parisc: Add defines for Huge page support
parisc: Drop unused MADV_xxxK_PAGES flags from asm/mman.h
parisc: Drop definition of start_thread_som for HP-UX SOM binaries
parisc: Fix wrong comment regarding first pmd entry flags
This patch adds huge page support to allow userspace to allocate huge
pages and to use hugetlbfs filesystem on 32- and 64-bit Linux kernels.
A later patch will add kernel support to map kernel text and data on
huge pages.
The only requirement is, that the kernel needs to be compiled for a
PA8X00 CPU (PA2.0 architecture). Older PA1.X CPUs do not support
variable page sizes. 64bit Kernels are compiled for PA2.0 by default.
Technically on parisc multiple physical huge pages may be needed to
emulate standard 2MB huge pages.
Signed-off-by: Helge Deller <deller@gmx.de>
Use the 22bit instead of the 17bit branch instruction on a 64bit kernel
to reach the do_syscall_trace_exit function from the gateway page.
A huge page enabled kernel may need the additional branch distance bits.
Signed-off-by: Helge Deller <deller@gmx.de>
For the 64bit kernel the initially 16 MB kernel memory might become too
small if you build a kernel with many modules built-in and with kernel
text and data areas mapped on huge pages.
This patch increases the initial mapping to 32MB for 64bit kernels and
keeps 16MB for 32bit kernels.
Signed-off-by: Helge Deller <deller@gmx.de>
A fault vector on parisc needs to be 2K aligned. Furthermore the
checksum of the fault vector needs to sum up to 0 which is being
calculated and written at runtime.
Up to now we aligned both PA20 and PA11 fault vectors on the same 4K
page in order to easily write the checksum after having mapped the
kernel read-only (by mapping this page only as read-write).
But when we want to map the kernel text and data on huge pages this
makes things harder.
So, simplify it by aligning both fault vectors on 2K boundries and write
the checksum before we map the page read-only.
Signed-off-by: Helge Deller <deller@gmx.de>
No need to use CONFIG_SMP around update_cr16_clocksource(). It checks for
num_online_cpus() beeing greater than 1, which is always 1 in UP builds.
Signed-off-by: Helge Deller <deller@gmx.de>
The attached change fixes the condition used in the "sub" instruction.
A double word comparison is needed. This fixes the 64-bit LWS CAS
operation on 64-bit kernels.
I can now enable 64-bit atomic support in GCC.
Cc: <stable@vger.kernel.org>
Signed-off-by: John David Anglin <dave.anglin>
Signed-off-by: Helge Deller <deller@gmx.de>
When detecting a serial port on newer PA-RISC machines (with iosapic) we have a
long way to go to find the right IRQ line, registering it, then registering the
serial port and the irq handler for the serial port. During this phase spurious
interrupts for the serial port may happen which then crashes the kernel because
the action handler might not have been set up yet.
So, basically it's a race condition between the serial port hardware and the
CPU which sets up the necessary fields in the irq sructs. The main reason for
this race is, that we unmask the serial port irqs too early without having set
up everything properly before (which isn't easily possible because we need the
IRQ number to register the serial ports).
This patch is a work-around for this problem. It adds checks to the CPU irq
handler to verify if the IRQ action field has been initialized already. If not,
we just skip this interrupt (which isn't critical for a serial port at bootup).
The real fix would probably involve rewriting all PA-RISC specific IRQ code
(for CPU, IOSAPIC, GSC and EISA) to use IRQ domains with proper parenting of
the irq chips and proper irq enabling along this line.
This bug has been in the PA-RISC port since the beginning, but the crashes
happened very rarely with currently used hardware. But on the latest machine
which I bought (a C8000 workstation), which uses the fastest CPUs (4 x PA8900,
1GHz) and which has the largest possible L1 cache size (64MB each), the kernel
crashed at every boot because of this race. So, without this patch the machine
would currently be unuseable.
For the record, here is the flow logic:
1. serial_init_chip() in 8250_gsc.c calls iosapic_serial_irq().
2. iosapic_serial_irq() calls txn_alloc_irq() to find the irq.
3. iosapic_serial_irq() calls cpu_claim_irq() to register the CPU irq
4. cpu_claim_irq() unmasks the CPU irq (which it shouldn't!)
5. serial_init_chip() then registers the 8250 port.
Problems:
- In step 4 the CPU irq shouldn't have been registered yet, but after step 5
- If serial irq happens between 4 and 5 have finished, the kernel will crash
Signed-off-by: Helge Deller <deller@gmx.de>
The increased use of pdtlb/pitlb instructions seemed to increase the
frequency of random segmentation faults building packages. Further, we
had a number of cases where TLB inserts would repeatedly fail and all
forward progress would stop. The Haskell ghc package caused a lot of
trouble in this area. The final indication of a race in pte handling was
this syslog entry on sibaris (C8000):
swap_free: Unused swap offset entry 00000004
BUG: Bad page map in process mysqld pte:00000100 pmd:019bbec5
addr:00000000ec464000 vm_flags:00100073 anon_vma:0000000221023828 mapping: (null) index:ec464
CPU: 1 PID: 9176 Comm: mysqld Not tainted 4.0.0-2-parisc64-smp #1 Debian 4.0.5-1
Backtrace:
[<0000000040173eb0>] show_stack+0x20/0x38
[<0000000040444424>] dump_stack+0x9c/0x110
[<00000000402a0d38>] print_bad_pte+0x1a8/0x278
[<00000000402a28b8>] unmap_single_vma+0x3d8/0x770
[<00000000402a4090>] zap_page_range+0xf0/0x198
[<00000000402ba2a4>] SyS_madvise+0x404/0x8c0
Note that the pte value is 0 except for the accessed bit 0x100. This bit
shouldn't be set without the present bit.
It should be noted that the madvise system call is probably a trigger for many
of the random segmentation faults.
In looking at the kernel code, I found the following problems:
1) The pte_clear define didn't take TLB lock when clearing a pte.
2) We didn't test pte present bit inside lock in exception support.
3) The pte and tlb locks needed to merged in order to ensure consistency
between page table and TLB. This also has the effect of serializing TLB
broadcasts on SMP systems.
The attached change implements the above and a few other tweaks to try
to improve performance. Based on the timing code, TLB purges are very
slow (e.g., ~ 209 cycles per page on rp3440). Thus, I think it
beneficial to test the split_tlb variable to avoid duplicate purges.
Probably, all PA 2.0 machines have combined TLBs.
I dropped using __flush_tlb_range in flush_tlb_mm as I realized all
applications and most threads have a stack size that is too large to
make this useful. I added some comments to this effect.
Since implementing 1 through 3, I haven't had any random segmentation
faults on mx3210 (rp3440) in about one week of building code and running
as a Debian buildd.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # v3.18+
Signed-off-by: Helge Deller <deller@gmx.de>
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Merge tag 'module_init-device_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull module_init replacement part one from Paul Gortmaker:
"Replace module_init with equivalent device_initcall in non modules.
This series of commits converts non-modular code that is using the
module_init() call to hook itself into the system to instead use
device_initcall().
The conversion is a runtime no-op, since module_init actually becomes
__initcall in the non-modular case, and that in turn gets mapped onto
device_initcall. A couple files show a larger negative diffstat,
representing ones that had a module_exit function that we remove here
vs previously relying on the linker to dispose of it.
We make this conversion now, so that we can relocate module_init from
init.h into module.h in the future.
The files changed here are just limited to those that would otherwise
have to add module.h to obviously non-modular code, in order to avoid
a compile fail, as testing has shown"
* tag 'module_init-device_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
MIPS: don't use module_init in non-modular cobalt/mtd.c file
drivers/leds: don't use module_init in non-modular leds-cobalt-raq.c
cris: don't use module_init for non-modular core eeprom.c code
tty/metag_da: Avoid module_init/module_exit in non-modular code
drivers/clk: don't use module_init in clk-nomadik.c which is non-modular
xtensa: don't use module_init for non-modular core network.c code
sh: don't use module_init in non-modular psw.c code
mn10300: don't use module_init in non-modular flash.c code
parisc64: don't use module_init for non-modular core perf code
parisc: don't use module_init for non-modular core pdc_cons code
cris: don't use module_init for non-modular core intmem.c code
ia64: don't use module_init in non-modular sim/simscsi.c code
ia64: don't use module_init for non-modular core kernel/mca.c code
arm: don't use module_init in non-modular mach-vexpress/spc.c code
powerpc: don't use module_init in non-modular 83xx suspend code
powerpc: use device_initcall for registering rtc devices
x86: don't use module_init in non-modular devicetree.c code
x86: don't use module_init in non-modular intel_mid_vrtc.c
This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls. Since parisc doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element. But this can help find problems with
drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The perf.c code depends on CONFIG_64BIT, so it is either built-in
or absent. It will never be modular, so using module_init as an
alias for __initcall is rather misleading.
Fix this up now, so that we can relocate module_init from
init.h into module.h in the future. If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing. Aside from it not making sense, it also
causes a ~10% increase in CPP overhead due to module.h having a
large list of headers itself -- for example compare line counts:
device_initcall() and <linux/init.h>
20238 arch/parisc/kernel/perf.i
module_init() and <linux/module.h>
22194 arch/parisc/kernel/perf.i
Direct use of __initcall is discouraged, vs prioritized ones.
Use of device_initcall is consistent with what __initcall
maps onto, and hence does not change the init order, making the
impact of this change zero. Should someone with real hardware
for boot testing want to change it later to arch_initcall or
something different, they can do that at a later date.
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The pdc_cons.c code is always built in. It will never be modular,
so using module_init as an alias for __initcall is rather
misleading.
Fix this up now, so that we can relocate module_init from
init.h into module.h in the future. If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.
Direct use of __initcall is discouraged, vs prioritized ones.
Use of device_initcall is consistent with what __initcall
maps onto, and hence does not change the init order, making the
impact of this change zero. Should someone with real hardware
for boot testing want to change it later to arch_initcall or
something different, they can do that at a later date.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).
In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().
Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.
faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.
This patch is based on a patch from Thomas Gleixner.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On architectures where the stack grows upwards (CONFIG_STACK_GROWSUP=y,
currently parisc and metag only) stack randomization sometimes leads to crashes
when the stack ulimit is set to lower values than STACK_RND_MASK (which is 8 MB
by default if not defined in arch-specific headers).
The problem is, that when the stack vm_area_struct is set up in fs/exec.c, the
additional space needed for the stack randomization (as defined by the value of
STACK_RND_MASK) was not taken into account yet and as such, when the stack
randomization code added a random offset to the stack start, the stack
effectively got smaller than what the user defined via rlimit_max(RLIMIT_STACK)
which then sometimes leads to out-of-stack situations and crashes.
This patch fixes it by adding the maximum possible amount of memory (based on
STACK_RND_MASK) which theoretically could be added by the stack randomization
code to the initial stack size. That way, the user-defined stack size is always
guaranteed to be at minimum what is defined via rlimit_max(RLIMIT_STACK).
This bug is currently not visible on the metag architecture, because on metag
STACK_RND_MASK is defined to 0 which effectively disables stack randomization.
The changes to fs/exec.c are inside an "#ifdef CONFIG_STACK_GROWSUP"
section, so it does not affect other platformws beside those where the
stack grows upwards (parisc and metag).
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org # v3.16+
The 'arg' argument to copy_thread() is only ever used when forking a new
kernel thread. Hence, rename it to 'kthread_arg' for clarity (and
consistency with do_fork() and other arch-specific implementations of
copy_thread()).
Signed-off-by: Alex Dowad <alexinbeijing@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
The only reason to keep parisc's private asm/scatterlist.h was that it
had the macro sg_virt_addr(). Convert all callers to use something else
(sometimes just sg->offset was enough, others should use sg_virt()), and
we can just use the asm-generic scatterlist.h instead.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Dave Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
