The following commit introduced a bug in one of our error paths:
819319fc93 ("kprobes: Return error if we fail to reuse kprobe instead of BUG_ON()")
it missed to handle the return value of kprobe_optready() as
error-value. In reality, the kprobe_optready() returns a bool
result, so "true" case must be passed instead of 0.
This causes some errors on kprobe boot-time selftests on ARM:
[ ] Beginning kprobe tests...
[ ] Probe ARM code
[ ] kprobe
[ ] kretprobe
[ ] ARM instruction simulation
[ ] Check decoding tables
[ ] Run test cases
[ ] FAIL: test_case_handler not run
[ ] FAIL: Test andge r10, r11, r14, asr r7
[ ] FAIL: Scenario 11
...
[ ] FAIL: Scenario 7
[ ] Total instruction simulation tests=1631, pass=1433 fail=198
[ ] kprobe tests failed
This can happen if an optimized probe is unregistered and next
kprobe is registered on same address until the previous probe
is not reclaimed.
If this happens, a hidden aggregated probe may be kept in memory,
and no new kprobe can probe same address. Also, in that case
register_kprobe() will return "1" instead of minus error value,
which can mislead caller logic.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naveen N . Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # v5.0+
Fixes: 819319fc93 ("kprobes: Return error if we fail to reuse kprobe instead of BUG_ON()")
Link: http://lkml.kernel.org/r/155530808559.32517.539898325433642204.stgit@devnote2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull libnvdimm fixes from Dan Williams:
"I debated holding this back for the v5.2 merge window due to the size
of the "zero-key" changes, but affected users would benefit from
having the fixes sooner. It did not make sense to change the zero-key
semantic in isolation for the "secure-erase" command, but instead
include it for all security commands.
The short background on the need for these changes is that some NVDIMM
platforms enable security with a default zero-key rather than let the
OS specify the initial key. This makes the security enabling that
landed in v5.0 unusable for some users.
Summary:
- Compatibility fix for nvdimm-security implementations with a
default zero-key.
- Miscellaneous small fixes for out-of-bound accesses, cleanup after
initialization failures, and missing debug messages"
* tag 'libnvdimm-fixes-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
tools/testing/nvdimm: Retain security state after overwrite
libnvdimm/pmem: fix a possible OOB access when read and write pmem
libnvdimm/security, acpi/nfit: unify zero-key for all security commands
libnvdimm/security: provide fix for secure-erase to use zero-key
libnvdimm/btt: Fix a kmemdup failure check
libnvdimm/namespace: Fix a potential NULL pointer dereference
acpi/nfit: Always dump _DSM output payload
Pull fsdax fix from Dan Williams:
"A single filesystem-dax fix. It has been lingering in -next for a long
while and there are no other fsdax fixes on the horizon:
- Avoid a crash scenario with architectures like powerpc that require
'pgtable_deposit' for the zero page"
* tag 'fsdax-fix-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
fs/dax: Deposit pagetable even when installing zero page
Merge page ref overflow branch.
Jann Horn reported that he can overflow the page ref count with
sufficient memory (and a filesystem that is intentionally extremely
slow).
Admittedly it's not exactly easy. To have more than four billion
references to a page requires a minimum of 32GB of kernel memory just
for the pointers to the pages, much less any metadata to keep track of
those pointers. Jann needed a total of 140GB of memory and a specially
crafted filesystem that leaves all reads pending (in order to not ever
free the page references and just keep adding more).
Still, we have a fairly straightforward way to limit the two obvious
user-controllable sources of page references: direct-IO like page
references gotten through get_user_pages(), and the splice pipe page
duplication. So let's just do that.
* branch page-refs:
fs: prevent page refcount overflow in pipe_buf_get
mm: prevent get_user_pages() from overflowing page refcount
mm: add 'try_get_page()' helper function
mm: make page ref count overflow check tighter and more explicit
Change pipe_buf_get() to return a bool indicating whether it succeeded
in raising the refcount of the page (if the thing in the pipe is a page).
This removes another mechanism for overflowing the page refcount. All
callers converted to handle a failure.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the page refcount wraps around past zero, it will be freed while
there are still four billion references to it. One of the possible
avenues for an attacker to try to make this happen is by doing direct IO
on a page multiple times. This patch makes get_user_pages() refuse to
take a new page reference if there are already more than two billion
references to the page.
Reported-by: Jann Horn <jannh@google.com>
Acked-by: Matthew Wilcox <willy@infradead.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the same as the traditional 'get_page()' function, but instead
of unconditionally incrementing the reference count of the page, it only
does so if the count was "safe". It returns whether the reference count
was incremented (and is marked __must_check, since the caller obviously
has to be aware of it).
Also like 'get_page()', you can't use this function unless you already
had a reference to the page. The intent is that you can use this
exactly like get_page(), but in situations where you want to limit the
maximum reference count.
The code currently does an unconditional WARN_ON_ONCE() if we ever hit
the reference count issues (either zero or negative), as a notification
that the conditional non-increment actually happened.
NOTE! The count access for the "safety" check is inherently racy, but
that doesn't matter since the buffer we use is basically half the range
of the reference count (ie we look at the sign of the count).
Acked-by: Matthew Wilcox <willy@infradead.org>
Cc: Jann Horn <jannh@google.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have a VM_BUG_ON() to check that the page reference count doesn't
underflow (or get close to overflow) by checking the sign of the count.
That's all fine, but we actually want to allow people to use a "get page
ref unless it's already very high" helper function, and we want that one
to use the sign of the page ref (without triggering this VM_BUG_ON).
Change the VM_BUG_ON to only check for small underflows (or _very_ close
to overflowing), and ignore overflows which have strayed into negative
territory.
Acked-by: Matthew Wilcox <willy@infradead.org>
Cc: Jann Horn <jannh@google.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block fixes from Jens Axboe:
"Set of fixes that should go into this round. This pull is larger than
I'd like at this time, but there's really no specific reason for that.
Some are fixes for issues that went into this merge window, others are
not. Anyway, this contains:
- Hardware queue limiting for virtio-blk/scsi (Dongli)
- Multi-page bvec fixes for lightnvm pblk
- Multi-bio dio error fix (Jason)
- Remove the cache hint from the io_uring tool side, since we didn't
move forward with that (me)
- Make io_uring SETUP_SQPOLL root restricted (me)
- Fix leak of page in error handling for pc requests (Jérôme)
- Fix BFQ regression introduced in this merge window (Paolo)
- Fix break logic for bio segment iteration (Ming)
- Fix NVMe cancel request error handling (Ming)
- NVMe pull request with two fixes (Christoph):
- fix the initial CSN for nvme-fc (James)
- handle log page offsets properly in the target (Keith)"
* tag 'for-linus-20190412' of git://git.kernel.dk/linux-block:
block: fix the return errno for direct IO
nvmet: fix discover log page when offsets are used
nvme-fc: correct csn initialization and increments on error
block: do not leak memory in bio_copy_user_iov()
lightnvm: pblk: fix crash in pblk_end_partial_read due to multipage bvecs
nvme: cancel request synchronously
blk-mq: introduce blk_mq_complete_request_sync()
scsi: virtio_scsi: limit number of hw queues by nr_cpu_ids
virtio-blk: limit number of hw queues by nr_cpu_ids
block, bfq: fix use after free in bfq_bfqq_expire
io_uring: restrict IORING_SETUP_SQPOLL to root
tools/io_uring: remove IOCQE_FLAG_CACHEHIT
block: don't use for-inside-for in bio_for_each_segment_all
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
Stable fix:
- Fix a deadlock in close() due to incorrect draining of RDMA queues
Bugfixes:
- Revert "SUNRPC: Micro-optimise when the task is known not to be
sleeping" as it is causing stack overflows
- Fix a regression where NFSv4 getacl and fs_locations stopped
working
- Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family.
- Fix xfstests failures due to incorrect copy_file_range() return
values"
* tag 'nfs-for-5.1-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
Revert "SUNRPC: Micro-optimise when the task is known not to be sleeping"
NFSv4.1 fix incorrect return value in copy_file_range
xprtrdma: Fix helper that drains the transport
NFS: Fix handling of reply page vector
NFS: Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family.
Pull SCSI fix from James Bottomley:
"One obvious fix for a ciostor data corruption on error bug"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: csiostor: fix missing data copy in csio_scsi_err_handler()
Pull clk fixes from Stephen Boyd:
"Here's more than a handful of clk driver fixes for changes that came
in during the merge window:
- Fix the AT91 sama5d2 programmable clk prescaler formula
- A bunch of Amlogic meson clk driver fixes for the VPU clks
- A DMI quirk for Intel's Bay Trail SoC's driver to properly mark pmc
clks as critical only when really needed
- Stop overwriting CLK_SET_RATE_PARENT flag in mediatek's clk gate
implementation
- Use the right structure to test for a frequency table in i.MX's
PLL_1416x driver"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: imx: Fix PLL_1416X not rounding rates
clk: mediatek: fix clk-gate flag setting
platform/x86: pmc_atom: Drop __initconst on dmi table
clk: x86: Add system specific quirk to mark clocks as critical
clk: meson: vid-pll-div: remove warning and return 0 on invalid config
clk: meson: pll: fix rounding and setting a rate that matches precisely
clk: meson-g12a: fix VPU clock parents
clk: meson: g12a: fix VPU clock muxes mask
clk: meson-gxbb: round the vdec dividers to closest
clk: at91: fix programmable clock for sama5d2
Pull PCI fixes from Bjorn Helgaas:
- Add a DMA alias quirk for another Marvell SATA device (Andre
Przywara)
- Fix a pciehp regression that broke safe removal of devices (Sergey
Miroshnichenko)
* tag 'pci-v5.1-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: pciehp: Ignore Link State Changes after powering off a slot
PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller
Pull powerpc fixes from Michael Ellerman:
"A minor build fix for 64-bit FLATMEM configs.
A fix for a boot failure on 32-bit powermacs.
My commit to fix CLOCK_MONOTONIC across Y2038 broke the 32-bit VDSO on
64-bit kernels, ie. compat mode, which is only used on big endian.
The rewrite of the SLB code we merged in 4.20 missed the fact that the
0x380 exception is also used with the Radix MMU to report out of range
accesses. This could lead to an oops if userspace tried to read from
addresses outside the user or kernel range.
Thanks to: Aneesh Kumar K.V, Christophe Leroy, Larry Finger, Nicholas
Piggin"
* tag 'powerpc-5.1-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm: Define MAX_PHYSMEM_BITS for all 64-bit configs
powerpc/64s/radix: Fix radix segment exception handling
powerpc/vdso32: fix CLOCK_MONOTONIC on PPC64
powerpc/32: Fix early boot failure with RTAS built-in
Pull arm64 fixes from Will Deacon:
"The main thing is a fix to our FUTEX_WAKE_OP implementation which was
unbelievably broken, but did actually work for the one scenario that
GLIBC used to use.
Summary:
- Fix stack unwinding so we ignore user stacks
- Fix ftrace module PLT trampoline initialisation checks
- Fix terminally broken implementation of FUTEX_WAKE_OP atomics"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value
arm64: backtrace: Don't bother trying to unwind the userspace stack
arm64/ftrace: fix inadvertent BUG() in trampoline check
Pull x86 fixes from Ingo Molnar:
"Fix typos in user-visible resctrl parameters, and also fix assembly
constraint bugs that might result in miscompilation"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Use stricter assembly constraints in bitops
x86/resctrl: Fix typos in the mba_sc mount option
Pull timer fix from Ingo Molnar:
"Fix the alarm_timer_remaining() return value"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Return correct remaining time
Pull scheduler fix from Ingo Molnar:
"Fix a NULL pointer dereference crash in certain environments"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Do not re-read ->h_load_next during hierarchical load calculation
Pull perf fixes from Ingo Molnar:
"Six kernel side fixes: three related to NMI handling on AMD systems, a
race fix, a kexec initialization fix and a PEBS sampling fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix perf_event_disable_inatomic() race
x86/perf/amd: Remove need to check "running" bit in NMI handler
x86/perf/amd: Resolve NMI latency issues for active PMCs
x86/perf/amd: Resolve race condition when disabling PMC
perf/x86/intel: Initialize TFA MSR
perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS
Pull locking fix from Ingo Molnar:
"Fixes a crash when accessing /proc/lockdep"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Zap lock classes even with lock debugging disabled
Kan Liang
Alexander Shishkin
Masami Hiramatsu
Linus Torvalds
Matthew Wilcox