Commit Graph

29401 Commits

Author SHA1 Message Date
Waiman Long
513e1073d5 locking/lockdep: Add debug_locks check in __lock_downgrade()
Tetsuo Handa had reported he saw an incorrect "downgrading a read lock"
warning right after a previous lockdep warning. It is likely that the
previous warning turned off lock debugging causing the lockdep to have
inconsistency states leading to the lock downgrade warning.

Fix that by add a check for debug_locks at the beginning of
__lock_downgrade().

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+53383ae265fb161ef488@syzkaller.appspotmail.com
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/1547093005-26085-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 09:03:27 +01:00
Ingo Molnar
31fe3cbbf2 Linux 5.0-rc5
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlxXYaEeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGkSQH/2yrfnviNPFYpZOR
 QQdc71Bfhkd8m85SmWIsSebkxmi3hKFVj15sGbWXd6+0/VxjEEGvQCZpvVwJceke
 LwDxtkKGg/74wAqJvlSAWxFNZ+Had4jDeoSoeQChddsBVXBBCxQx2v6ECg3o2x7W
 k8Z8t4+3RijDf8fYXY9ETyO2zW8R/wgT+dnl+DPgUH7u4dxh7FzAUfc4bgZIDg+i
 FzBQfbTJuz4BU7uRZ9IJiwhWKv0Iyi2DR3BY8Z1pqEpRaUMJMrCs2WGytHbTgt9e
 0EtO1airbVneU4eumU/ZaF9cyEbah9HousEPnP7J09WG4s/Odxc4zE+uK1QqS2im
 5Xv88is=
 =dVd1
 -----END PGP SIGNATURE-----

Merge tag 'v5.0-rc5' into locking/core to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:57:24 +01:00
Linus Torvalds
cc6810e36b Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cpu hotplug fixes from Thomas Gleixner:
 "Two fixes for the cpu hotplug machinery:

   - Replace the overly clever 'SMT disabled by BIOS' detection logic as
     it breaks KVM scenarios and prevents speculation control updates
     when the Hyperthreads are brought online late after boot.

   - Remove a redundant invocation of the speculation control update
     function"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM
  x86/speculation: Remove redundant arch_smt_update() invocation
2019-02-03 09:02:03 -08:00
Linus Torvalds
58f6d4287a Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A pile of perf updates:

   - Fix broken sanity check in the /proc/sys/kernel/perf_cpu_time_max_percent
     write handler

   - Cure a perf script crash which caused by an unitinialized data
     structure

   - Highlight the hottest instruction in perf top and not a random one

   - Cure yet another clang issue when building perf python

   - Handle topology entries with no CPU correctly in the tools

   - Handle perf data which contains both tracepoints and performance
     counter entries correctly.

   - Add a missing NULL pointer check in perf ordered_events_free()"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf script: Fix crash when processing recorded stat data
  perf top: Fix wrong hottest instruction highlighted
  perf tools: Handle TOPOLOGY headers with no CPU
  perf python: Remove -fstack-clash-protection when building with some clang versions
  perf core: Fix perf_proc_update_handler() bug
  perf script: Fix crash with printing mixed trace point and other events
  perf ordered_events: Fix crash in ordered_events__free
2019-02-03 08:59:51 -08:00
Johannes Weiner
1b69ac6b40 psi: fix aggregation idle shut-off
psi has provisions to shut off the periodic aggregation worker when
there is a period of no task activity - and thus no data that needs
aggregating.  However, while developing psi monitoring, Suren noticed
that the aggregation clock currently won't stay shut off for good.

Debugging this revealed a flaw in the idle design: an aggregation run
will see no task activity and decide to go to sleep; shortly thereafter,
the kworker thread that executed the aggregation will go idle and cause
a scheduling change, during which the psi callback will kick the
!pending worker again.  This will ping-pong forever, and is equivalent
to having no shut-off logic at all (but with more code!)

Fix this by exempting aggregation workers from psi's clock waking logic
when the state change is them going to sleep.  To do this, tag workers
with the last work function they executed, and if in psi we see a worker
going to sleep after aggregating psi data, we will not reschedule the
aggregation work item.

What if the worker is also executing other items before or after?

Any psi state times that were incurred by work items preceding the
aggregation work will have been collected from the per-cpu buckets
during the aggregation itself.  If there are work items following the
aggregation work, the worker's last_func tag will be overwritten and the
aggregator will be kept alive to process this genuine new activity.

If the aggregation work is the last thing the worker does, and we decide
to go idle, the brief period of non-idle time incurred between the
aggregation run and the kworker's dequeue will be stranded in the
per-cpu buckets until the clock is woken by later activity.  But that
should not be a problem.  The buckets can hold 4s worth of time, and
future activity will wake the clock with a 2s delay, giving us 2s worth
of data we can leave behind when disabling aggregation.  If it takes a
worker more than two seconds to go idle after it finishes its last work
item, we likely have bigger problems in the system, and won't notice one
sample that was averaged with a bogus per-CPU weight.

Link: http://lkml.kernel.org/r/20190116193501.1910-1-hannes@cmpxchg.org
Fixes: eb414681d5 ("psi: pressure stall information for CPU, memory, and IO")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-01 15:46:23 -08:00
Andrei Vagin
8fb335e078 kernel/exit.c: release ptraced tasks before zap_pid_ns_processes
Currently, exit_ptrace() adds all ptraced tasks in a dead list, then
zap_pid_ns_processes() waits on all tasks in a current pidns, and only
then are tasks from the dead list released.

zap_pid_ns_processes() can get stuck on waiting tasks from the dead
list.  In this case, we will have one unkillable process with one or
more dead children.

Thanks to Oleg for the advice to release tasks in find_child_reaper().

Link: http://lkml.kernel.org/r/20190110175200.12442-1-avagin@gmail.com
Fixes: 7c8bd2322c ("exit: ptrace: shift "reap dead" code from exit_ptrace() to forget_original_parent()")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-01 15:46:23 -08:00
Josh Poimboeuf
b284909aba cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM
With the following commit:

  73d5e2b472 ("cpu/hotplug: detect SMT disabled by BIOS")

... the hotplug code attempted to detect when SMT was disabled by BIOS,
in which case it reported SMT as permanently disabled.  However, that
code broke a virt hotplug scenario, where the guest is booted with only
primary CPU threads, and a sibling is brought online later.

The problem is that there doesn't seem to be a way to reliably
distinguish between the HW "SMT disabled by BIOS" case and the virt
"sibling not yet brought online" case.  So the above-mentioned commit
was a bit misguided, as it permanently disabled SMT for both cases,
preventing future virt sibling hotplugs.

Going back and reviewing the original problems which were attempted to
be solved by that commit, when SMT was disabled in BIOS:

  1) /sys/devices/system/cpu/smt/control showed "on" instead of
     "notsupported"; and

  2) vmx_vm_init() was incorrectly showing the L1TF_MSG_SMT warning.

I'd propose that we instead consider #1 above to not actually be a
problem.  Because, at least in the virt case, it's possible that SMT
wasn't disabled by BIOS and a sibling thread could be brought online
later.  So it makes sense to just always default the smt control to "on"
to allow for that possibility (assuming cpuid indicates that the CPU
supports SMT).

The real problem is #2, which has a simple fix: change vmx_vm_init() to
query the actual current SMT state -- i.e., whether any siblings are
currently online -- instead of looking at the SMT "control" sysfs value.

So fix it by:

  a) reverting the original "fix" and its followup fix:

     73d5e2b472 ("cpu/hotplug: detect SMT disabled by BIOS")
     bc2d8d262c ("cpu/hotplug: Fix SMT supported evaluation")

     and

  b) changing vmx_vm_init() to query the actual current SMT state --
     instead of the sysfs control value -- to determine whether the L1TF
     warning is needed.  This also requires the 'sched_smt_present'
     variable to exported, instead of 'cpu_smt_control'.

Fixes: 73d5e2b472 ("cpu/hotplug: detect SMT disabled by BIOS")
Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Joe Mario <jmario@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/e3a85d585da28cc333ecbc1e78ee9216e6da9396.1548794349.git.jpoimboe@redhat.com
2019-01-30 19:27:00 +01:00
Zhenzhong Duan
34d66caf25 x86/speculation: Remove redundant arch_smt_update() invocation
With commit a74cfffb03 ("x86/speculation: Rework SMT state change"),
arch_smt_update() is invoked from each individual CPU hotplug function.

Therefore the extra arch_smt_update() call in the sysfs SMT control is
redundant.

Fixes: a74cfffb03 ("x86/speculation: Rework SMT state change")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <konrad.wilk@oracle.com>
Cc: <dwmw@amazon.co.uk>
Cc: <bp@suse.de>
Cc: <srinivas.eeda@oracle.com>
Cc: <peterz@infradead.org>
Cc: <hpa@zytor.com>
Link: https://lkml.kernel.org/r/e2e064f2-e8ef-42ca-bf4f-76b612964752@default
2019-01-29 22:20:24 +01:00
Greg Kroah-Hartman
0365aeba50 futex: No need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the return
value.  The function can work or not, but the code logic should never do
something different based on this.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190122152151.16139-40-gregkh@linuxfoundation.org
2019-01-29 20:15:48 +01:00
Linus Torvalds
f907bb4c32 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Glexiner:
 "A single regression fix to address the unintended breakage of posix
  cpu timers.

  This is caused by a new sanity check in the common code, which fails
  for posix cpu timers under certain conditions because the posix cpu
  timer code never updates the variable which is checked"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-cpu-timers: Unbreak timer rearming
2019-01-27 11:55:06 -08:00
Linus Torvalds
9881051828 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
 "A small series of fixes which all address possible missed wakeups:

   - Document and fix the wakeup ordering of wake_q

   - Add the missing barrier in rcuwait_wake_up(), which was documented
     in the comment but missing in the code

   - Fix the possible missed wakeups in the rwsem and futex code"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Fix (possible) missed wakeup
  futex: Fix (possible) missed wakeup
  sched/wake_q: Fix wakeup ordering for wake_q
  sched/wake_q: Document wake_q_add()
  sched/wait: Fix rcuwait_wake_up() ordering
2019-01-27 11:52:50 -08:00
Linus Torvalds
0d484375d7 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "A small set of fixes for the interrupt subsystem:

   - Fix a double increment in the irq descriptor allocator which
     resulted in a sanity check only being done for every second
     affinity mask

   - Add a missing device tree translation in the stm32-exti driver.
     Without that the interrupt association is completely wrong.

   - Initialize the mutex in the GIC-V3 MBI driver

   - Fix the alignment for aliasing devices in the GIC-V3-ITS driver so
     multi MSI allocations work correctly

   - Ensure that the initial affinity of a interrupt is not empty at
     startup time.

   - Drop bogus include in the madera irq chip driver

   - Fix KernelDoc regression"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Align PCI Multi-MSI allocation on their size
  genirq/irqdesc: Fix double increment in alloc_descs()
  genirq: Fix the kerneldoc comment for struct irq_affinity_desc
  irqchip/madera: Drop GPIO includes
  irqchip/gic-v3-mbi: Fix uninitialized mbi_lock
  irqchip/stm32-exti: Add domain translate function
  genirq: Make sure the initial affinity is not empty
2019-01-27 11:25:38 -08:00
Ingo Molnar
d3c8c0af75 perf/urgent fixes:
Kernel:
 
   Stephane Eranian:
 
   - Fix perf_proc_update_handler() bug.
 
 perf script:
 
   Andi Kleen:
 
   - Fix crash with printing mixed trace point and other events.
 
   Tony Jones:
 
   - Fix crash when processing recorded stat data.
 
 perf top:
 
   He Kuang:
 
   - Fix wrong hottest instruction highlighted.
 
 perf python:
 
   Arnaldo Carvalho de Melo:
 
   - Remove -fstack-clash-protection when building with some clang versions.
 
 perf ordered_events:
 
   Jiri Olsa:
 
   - Fix out of buffers crash in ordered_events__free().
 
 perf cpu_map:
 
   Stephane Eranian:
 
   - Handle TOPOLOGY headers with no CPU.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXEYQMgAKCRCyPKLppCJ+
 J/pYAP0c+6frwxCAll72bigi+/+5t+1kc/zpM5jNgt97moGh2AD+KKrN5h4E0Z/J
 g5T2FOpiwB4cxpVjYTVRchDlx9JohgA=
 =X2zj
 -----END PGP SIGNATURE-----

Merge tag 'perf-urgent-for-mingo-5.0-20190121' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

Kernel:

  Stephane Eranian:

  - Fix perf_proc_update_handler() bug.

perf script:

  Andi Kleen:

  - Fix crash with printing mixed trace point and other events.

  Tony Jones:

  - Fix crash when processing recorded stat data.

perf top:

  He Kuang:

  - Fix wrong hottest instruction highlighted.

perf python:

  Arnaldo Carvalho de Melo:

  - Remove -fstack-clash-protection when building with some clang versions.

perf ordered_events:

  Jiri Olsa:

  - Fix out of buffers crash in ordered_events__free().

perf cpu_map:

  Stephane Eranian:

  - Handle TOPOLOGY headers with no CPU.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-22 11:08:47 +01:00
Frederic Weisbecker
bba2a8f1f9 locking/lockdep: Provide enum lock_usage_bit mask names
It makes the code more self-explanatory and tells throughout the code
what magic number refers to:

 - state (Hardirq/Softirq)
 - direction (used in or enabled above state)
 - read or write

We can even remove some comments that were compensating for the lack of
those constant names.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/1545973321-24422-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:56 +01:00
Frederic Weisbecker
436a49ae7b locking/lockdep: Simplify mark_held_locks()
The enum mark_type appears a bit artificial here. We can directly pass
the base enum lock_usage_bit value to mark_held_locks(). All we need
then is to add the read index for each lock if necessary. It makes the
code clearer.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/1545973321-24422-2-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:54 +01:00
Valentin Schneider
b5a4e2bb0f Revert "sched/core: Take the hotplug lock in sched_init_smp()"
This reverts commit 40fa3780ba.

Now that we have a system-wide muting of hotplug lockdep during init,
this is no longer needed.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: cai@gmx.us
Cc: daniel.lezcano@linaro.org
Cc: dietmar.eggemann@arm.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: longman@redhat.com
Cc: marc.zyngier@arm.com
Cc: mark.rutland@arm.com
Link: https://lkml.kernel.org/r/1545243796-23224-3-git-send-email-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:54 +01:00
Valentin Schneider
ce48c457b9 cpu/hotplug: Mute hotplug lockdep during init
Since we've had:

  commit cb538267ea ("jump_label/lockdep: Assert we hold the hotplug lock for _cpuslocked() operations")

we've been getting some lockdep warnings during init, such as on HiKey960:

[    0.820495] WARNING: CPU: 4 PID: 0 at kernel/cpu.c:316 lockdep_assert_cpus_held+0x3c/0x48
[    0.820498] Modules linked in:
[    0.820509] CPU: 4 PID: 0 Comm: swapper/4 Tainted: G S                4.20.0-rc5-00051-g4cae42a #34
[    0.820511] Hardware name: HiKey960 (DT)
[    0.820516] pstate: 600001c5 (nZCv dAIF -PAN -UAO)
[    0.820520] pc : lockdep_assert_cpus_held+0x3c/0x48
[    0.820523] lr : lockdep_assert_cpus_held+0x38/0x48
[    0.820526] sp : ffff00000a9cbe50
[    0.820528] x29: ffff00000a9cbe50 x28: 0000000000000000
[    0.820533] x27: 00008000b69e5000 x26: ffff8000bff4cfe0
[    0.820537] x25: ffff000008ba69e0 x24: 0000000000000001
[    0.820541] x23: ffff000008fce000 x22: ffff000008ba70c8
[    0.820545] x21: 0000000000000001 x20: 0000000000000003
[    0.820548] x19: ffff00000a35d628 x18: ffffffffffffffff
[    0.820552] x17: 0000000000000000 x16: 0000000000000000
[    0.820556] x15: ffff00000958f848 x14: 455f3052464d4d34
[    0.820559] x13: 00000000769dde98 x12: ffff8000bf3f65a8
[    0.820564] x11: 0000000000000000 x10: ffff00000958f848
[    0.820567] x9 : ffff000009592000 x8 : ffff00000958f848
[    0.820571] x7 : ffff00000818ffa0 x6 : 0000000000000000
[    0.820574] x5 : 0000000000000000 x4 : 0000000000000001
[    0.820578] x3 : 0000000000000000 x2 : 0000000000000001
[    0.820582] x1 : 00000000ffffffff x0 : 0000000000000000
[    0.820587] Call trace:
[    0.820591]  lockdep_assert_cpus_held+0x3c/0x48
[    0.820598]  static_key_enable_cpuslocked+0x28/0xd0
[    0.820606]  arch_timer_check_ool_workaround+0xe8/0x228
[    0.820610]  arch_timer_starting_cpu+0xe4/0x2d8
[    0.820615]  cpuhp_invoke_callback+0xe8/0xd08
[    0.820619]  notify_cpu_starting+0x80/0xb8
[    0.820625]  secondary_start_kernel+0x118/0x1d0

We've also had a similar warning in sched_init_smp() for every
asymmetric system that would enable the sched_asym_cpucapacity static
key, although that was singled out in:

  commit 40fa3780ba ("sched/core: Take the hotplug lock in sched_init_smp()")

Those warnings are actually harmless, since we cannot have hotplug
operations at the time they appear. Instead of starting to sprinkle
useless hotplug lock operations in the init codepaths, mute the
warnings until they start warning about real problems.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: cai@gmx.us
Cc: daniel.lezcano@linaro.org
Cc: dietmar.eggemann@arm.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: longman@redhat.com
Cc: marc.zyngier@arm.com
Cc: mark.rutland@arm.com
Link: https://lkml.kernel.org/r/1545243796-23224-2-git-send-email-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:53 +01:00
Waiman Long
7149258057 locking/lockdep: Add debug_locks check in __lock_downgrade()
Tetsuo Handa had reported he saw an incorrect "downgrading a read lock"
warning right after a previous lockdep warning. It is likely that the
previous warning turned off lock debugging causing the lockdep to have
inconsistency states leading to the lock downgrade warning.

Fix that by add a check for debug_locks at the beginning of
__lock_downgrade().

Debugged-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+53383ae265fb161ef488@syzkaller.appspotmail.com
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/1547093005-26085-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:51 +01:00
Davidlohr Bueso
87ff19cb2f sched/wake_q: Add branch prediction hint to wake_q_add() cmpxchg
The cmpxchg() will fail when the task is already in the process
of waking up, and as such is an extremely rare occurrence.
Micro-optimize the call and put an unlikely() around it.

To no surprise, when using CONFIG_PROFILE_ANNOTATED_BRANCHES
under a number of workloads the incorrect rate was a mere 1-2%.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yongji Xie <elohimes@gmail.com>
Cc: andrea.parri@amarulasolutions.com
Cc: lilin24@baidu.com
Cc: liuqi16@baidu.com
Cc: nixun@baidu.com
Cc: xieyongji@baidu.com
Cc: yuanlinsi01@baidu.com
Cc: zhangyu31@baidu.com
Link: https://lkml.kernel.org/r/20181203053130.gwkw6kg72azt2npb@linux-r8p5
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:18:50 +01:00
Xie Yongji
e158488be2 locking/rwsem: Fix (possible) missed wakeup
Because wake_q_add() can imply an immediate wakeup (cmpxchg failure
case), we must not rely on the wakeup being delayed. However, commit:

  e38513905e ("locking/rwsem: Rework zeroing reader waiter->task")

relies on exactly that behaviour in that the wakeup must not happen
until after we clear waiter->task.

[ peterz: Added changelog. ]

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e38513905e ("locking/rwsem: Rework zeroing reader waiter->task")
Link: https://lkml.kernel.org/r/1543495830-2644-1-git-send-email-xieyongji@baidu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:15:39 +01:00
Peter Zijlstra
b061c38bef futex: Fix (possible) missed wakeup
We must not rely on wake_q_add() to delay the wakeup; in particular
commit:

  1d0dcb3ad9 ("futex: Implement lockless wakeups")

moved wake_q_add() before smp_store_release(&q->lock_ptr, NULL), which
could result in futex_wait() waking before observing ->lock_ptr ==
NULL and going back to sleep again.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 1d0dcb3ad9 ("futex: Implement lockless wakeups")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:15:38 +01:00
Peter Zijlstra
4c4e373156 sched/wake_q: Fix wakeup ordering for wake_q
Notable cmpxchg() does not provide ordering when it fails, however
wake_q_add() requires ordering in this specific case too. Without this
it would be possible for the concurrent wakeup to not observe our
prior state.

Andrea Parri provided:

  C wake_up_q-wake_q_add

  {
	int next = 0;
	int y = 0;
  }

  P0(int *next, int *y)
  {
	int r0;

	/* in wake_up_q() */

	WRITE_ONCE(*next, 1);   /* node->next = NULL */
	smp_mb();               /* implied by wake_up_process() */
	r0 = READ_ONCE(*y);
  }

  P1(int *next, int *y)
  {
	int r1;

	/* in wake_q_add() */

	WRITE_ONCE(*y, 1);      /* wake_cond = true */
	smp_mb__before_atomic();
	r1 = cmpxchg_relaxed(next, 1, 2);
  }

  exists (0:r0=0 /\ 1:r1=0)

  This "exists" clause cannot be satisfied according to the LKMM:

  Test wake_up_q-wake_q_add Allowed
  States 3
  0:r0=0; 1:r1=1;
  0:r0=1; 1:r1=0;
  0:r0=1; 1:r1=1;
  No
  Witnesses
  Positive: 0 Negative: 3
  Condition exists (0:r0=0 /\ 1:r1=0)
  Observation wake_up_q-wake_q_add Never 0 3

Reported-by: Yongji Xie <elohimes@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:15:37 +01:00
Peter Zijlstra
e6018c0f5c sched/wake_q: Document wake_q_add()
The only guarantee provided by wake_q_add() is that a wakeup will
happen after it, it does _NOT_ guarantee the wakeup will be delayed
until the matching wake_up_q().

If wake_q_add() fails the cmpxchg() a concurrent wakeup is pending and
that can happen at any time after the cmpxchg(). This means we should
not rely on the wakeup happening at wake_q_up(), but should be ready
for wake_q_add() to issue the wakeup.

The delay; if provided (most likely); should only result in more efficient
behaviour.

Reported-by: Yongji Xie <elohimes@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:15:36 +01:00
Prateek Sood
6dc080eeb2 sched/wait: Fix rcuwait_wake_up() ordering
For some peculiar reason rcuwait_wake_up() has the right barrier in
the comment, but not in the code.

This mistake has been observed to cause a deadlock in the following
situation:

    P1					P2

    percpu_up_read()			percpu_down_write()
      rcu_sync_is_idle() // false
					  rcu_sync_enter()
					  ...
      __percpu_up_read()

[S] ,-  __this_cpu_dec(*sem->read_count)
    |   smp_rmb();
[L] |   task = rcu_dereference(w->task) // NULL
    |
    |				    [S]	    w->task = current
    |					    smp_mb();
    |				    [L]	    readers_active_check() // fail
    `-> <store happens here>

Where the smp_rmb() (obviously) fails to constrain the store.

[ peterz: Added changelog. ]

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8f95c90ceb ("sched/wait, RCU: Introduce rcuwait machinery")
Link: https://lkml.kernel.org/r/1543590656-7157-1-git-send-email-prsood@codeaurora.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:15:36 +01:00
Linus Torvalds
7d0ae236ed Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix endless loop in nf_tables, from Phil Sutter.

 2) Fix cross namespace ip6_gre tunnel hash list corruption, from
    Olivier Matz.

 3) Don't be too strict in phy_start_aneg() otherwise we might not allow
    restarting auto negotiation. From Heiner Kallweit.

 4) Fix various KMSAN uninitialized value cases in tipc, from Ying Xue.

 5) Memory leak in act_tunnel_key, from Davide Caratti.

 6) Handle chip errata of mv88e6390 PHY, from Andrew Lunn.

 7) Remove linear SKB assumption in fou/fou6, from Eric Dumazet.

 8) Missing udplite rehash callbacks, from Alexey Kodanev.

 9) Log dirty pages properly in vhost, from Jason Wang.

10) Use consume_skb() in neigh_probe() as this is a normal free not a
    drop, from Yang Wei. Likewise in macvlan_process_broadcast().

11) Missing device_del() in mdiobus_register() error paths, from Thomas
    Petazzoni.

12) Fix checksum handling of short packets in mlx5, from Cong Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (96 commits)
  bpf: in __bpf_redirect_no_mac pull mac only if present
  virtio_net: bulk free tx skbs
  net: phy: phy driver features are mandatory
  isdn: avm: Fix string plus integer warning from Clang
  net/mlx5e: Fix cb_ident duplicate in indirect block register
  net/mlx5e: Fix wrong (zero) TX drop counter indication for representor
  net/mlx5e: Fix wrong error code return on FEC query failure
  net/mlx5e: Force CHECKSUM_UNNECESSARY for short ethernet frames
  tools: bpftool: Cleanup license mess
  bpf: fix inner map masking to prevent oob under speculation
  bpf: pull in pkt_sched.h header for tooling to fix bpftool build
  selftests: forwarding: Add a test case for externally learned FDB entries
  selftests: mlxsw: Test FDB offload indication
  mlxsw: spectrum_switchdev: Do not treat static FDB entries as sticky
  net: bridge: Mark FDB entries that were added by user as such
  mlxsw: spectrum_fid: Update dummy FID index
  mlxsw: pci: Return error on PCI reset timeout
  mlxsw: pci: Increase PCI SW reset timeout
  mlxsw: pci: Ring CQ's doorbell before RDQ's
  MAINTAINERS: update email addresses of liquidio driver maintainers
  ...
2019-01-21 12:52:31 +13:00
Daniel Borkmann
9d5564ddcf bpf: fix inner map masking to prevent oob under speculation
During review I noticed that inner meta map setup for map in
map is buggy in that it does not propagate all needed data
from the reference map which the verifier is later accessing.

In particular one such case is index masking to prevent out of
bounds access under speculative execution due to missing the
map's unpriv_array/index_mask field propagation. Fix this such
that the verifier is generating the correct code for inlined
lookups in case of unpriviledged use.

Before patch (test_verifier's 'map in map access' dump):

  # bpftool prog dump xla id 3
     0: (62) *(u32 *)(r10 -4) = 0
     1: (bf) r2 = r10
     2: (07) r2 += -4
     3: (18) r1 = map[id:4]
     5: (07) r1 += 272                |
     6: (61) r0 = *(u32 *)(r2 +0)     |
     7: (35) if r0 >= 0x1 goto pc+6   | Inlined map in map lookup
     8: (54) (u32) r0 &= (u32) 0      | with index masking for
     9: (67) r0 <<= 3                 | map->unpriv_array.
    10: (0f) r0 += r1                 |
    11: (79) r0 = *(u64 *)(r0 +0)     |
    12: (15) if r0 == 0x0 goto pc+1   |
    13: (05) goto pc+1                |
    14: (b7) r0 = 0                   |
    15: (15) if r0 == 0x0 goto pc+11
    16: (62) *(u32 *)(r10 -4) = 0
    17: (bf) r2 = r10
    18: (07) r2 += -4
    19: (bf) r1 = r0
    20: (07) r1 += 272                |
    21: (61) r0 = *(u32 *)(r2 +0)     | Index masking missing (!)
    22: (35) if r0 >= 0x1 goto pc+3   | for inner map despite
    23: (67) r0 <<= 3                 | map->unpriv_array set.
    24: (0f) r0 += r1                 |
    25: (05) goto pc+1                |
    26: (b7) r0 = 0                   |
    27: (b7) r0 = 0
    28: (95) exit

After patch:

  # bpftool prog dump xla id 1
     0: (62) *(u32 *)(r10 -4) = 0
     1: (bf) r2 = r10
     2: (07) r2 += -4
     3: (18) r1 = map[id:2]
     5: (07) r1 += 272                |
     6: (61) r0 = *(u32 *)(r2 +0)     |
     7: (35) if r0 >= 0x1 goto pc+6   | Same inlined map in map lookup
     8: (54) (u32) r0 &= (u32) 0      | with index masking due to
     9: (67) r0 <<= 3                 | map->unpriv_array.
    10: (0f) r0 += r1                 |
    11: (79) r0 = *(u64 *)(r0 +0)     |
    12: (15) if r0 == 0x0 goto pc+1   |
    13: (05) goto pc+1                |
    14: (b7) r0 = 0                   |
    15: (15) if r0 == 0x0 goto pc+12
    16: (62) *(u32 *)(r10 -4) = 0
    17: (bf) r2 = r10
    18: (07) r2 += -4
    19: (bf) r1 = r0
    20: (07) r1 += 272                |
    21: (61) r0 = *(u32 *)(r2 +0)     |
    22: (35) if r0 >= 0x1 goto pc+4   | Now fixed inlined inner map
    23: (54) (u32) r0 &= (u32) 0      | lookup with proper index masking
    24: (67) r0 <<= 3                 | for map->unpriv_array.
    25: (0f) r0 += r1                 |
    26: (05) goto pc+1                |
    27: (b7) r0 = 0                   |
    28: (b7) r0 = 0
    29: (95) exit

Fixes: b2157399cc ("bpf: prevent out-of-bounds speculation")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-18 15:19:56 -08:00
Stephane Eranian
1a51c5da5a perf core: Fix perf_proc_update_handler() bug
The perf_proc_update_handler() handles /proc/sys/kernel/perf_event_max_sample_rate
syctl variable.  When the PMU IRQ handler timing monitoring is disabled, i.e,
when /proc/sys/kernel/perf_cpu_time_max_percent is equal to 0 or 100,
then no modification to sysctl_perf_event_sample_rate is allowed to prevent
possible hang from wrong values.

The problem is that the test to prevent modification is made after the
sysctl variable is modified in perf_proc_update_handler().

You get an error:

  $ echo 10001 >/proc/sys/kernel/perf_event_max_sample_rate
  echo: write error: invalid argument

But the value is still modified causing all sorts of inconsistencies:

  $ cat /proc/sys/kernel/perf_event_max_sample_rate
  10001

This patch fixes the problem by moving the parsing of the value after
the test.

Committer testing:

  # echo 100 > /proc/sys/kernel/perf_cpu_time_max_percent
  # echo 10001 > /proc/sys/kernel/perf_event_max_sample_rate
  -bash: echo: write error: Invalid argument
  # cat /proc/sys/kernel/perf_event_max_sample_rate
  10001
  #

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1547169436-6266-1-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-18 11:10:38 -03:00
Huacai Chen
12fee4cd5b genirq/irqdesc: Fix double increment in alloc_descs()
The recent rework of alloc_descs() introduced a double increment of the
loop counter. As a consequence only every second affinity mask is
validated.

Remove it.

[ tglx: Massaged changelog ]

Fixes: c410abbbac ("genirq/affinity: Add is_managed to struct irq_affinity_desc")
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: Huacai Chen <chenhuacai@gmail.com>
Cc: Dou Liyang <douliyangs@gmail.com>
Link: https://lkml.kernel.org/r/1547694009-16261-1-git-send-email-chenhc@lemote.com
2019-01-18 00:43:09 +01:00
Linus Torvalds
6d060fa390 Merge branch 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "A tiny fix for v5.0-rc2:

  This fixes an issue with GPU cards not working anymore with the DMA
  mapping work Christopher did - as the SWIOTLB is initialized first and
  then free'd (as IOMMU is available) but we forgot to clear our start
  and end entries which are used and BOOM"

* 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb: clear io_tlb_start and io_tlb_end in swiotlb_exit
2019-01-18 06:22:08 +12:00
Mathieu Malaterre
c8dc79806e bpf: Annotate implicit fall through in cgroup_dev_func_proto
There is a plan to build the kernel with -Wimplicit-fallthrough
and this place in the code produced a warnings (W=1).

This commit removes the following warning:

  kernel/bpf/cgroup.c:719:6: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-17 16:52:23 +01:00
Mathieu Malaterre
583c531853 bpf: Make function btf_name_offset_valid static
Initially in commit 69b693f0ae ("bpf: btf: Introduce BPF Type Format
(BTF)") the function 'btf_name_offset_valid' was introduced as static
function it was later on changed to a non-static one, and then finally
in commit 23127b33ec ("bpf: Create a new btf_name_by_offset() for
non type name use case") the function prototype was removed.

Revert back to original implementation and make the function static.
Remove warning triggered with W=1:

  kernel/bpf/btf.c:470:6: warning: no previous prototype for 'btf_name_offset_valid' [-Wmissing-prototypes]

Fixes: 23127b33ec ("bpf: Create a new btf_name_by_offset() for non type name use case")
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-17 16:47:05 +01:00
Stanislav Fomichev
4af396ae48 bpf: zero out build_id for BPF_STACK_BUILD_ID_IP
When returning BPF_STACK_BUILD_ID_IP from stack_map_get_build_id_offset,
make sure that build_id field is empty. Since we are using percpu
free list, there is a possibility that we might reuse some previous
bpf_stack_build_id with non-zero build_id.

Fixes: 615755a77b ("bpf: extend stackmap to save binary_build_id+offset instead of address")
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-17 16:42:35 +01:00
Stanislav Fomichev
0b698005a9 bpf: don't assume build-id length is always 20 bytes
Build-id length is not fixed to 20, it can be (`man ld` /--build-id):
  * 128-bit (uuid)
  * 160-bit (sha1)
  * any length specified in ld --build-id=0xhexstring

To fix the issue of missing BPF_STACK_BUILD_ID_VALID for shorter build-ids,
assume that build-id is somewhere in the range of 1 .. 20.
Set the remaining bytes to zero.

v2:
* don't introduce new "len = min(BPF_BUILD_ID_SIZE, nhdr->n_descsz)",
  we already know that nhdr->n_descsz <= BPF_BUILD_ID_SIZE if we enter
  this 'if' condition

Fixes: 615755a77b ("bpf: extend stackmap to save binary_build_id+offset instead of address")
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-17 16:42:35 +01:00
Christoph Hellwig
227a76b647 swiotlb: clear io_tlb_start and io_tlb_end in swiotlb_exit
Otherwise is_swiotlb_buffer will return false positives when
we first initialize a swiotlb buffer, but then free it because
we have an IOMMU available.

Fixes: 55897af630 ("dma-direct: merge swiotlb_dma_ops into the dma_direct code")
Reported-by: Sibren Vasse <sibren@sibrenvasse.nl>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Sibren Vasse <sibren@sibrenvasse.nl>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2019-01-16 09:59:17 -05:00
Tycho Andersen
a811dc6155 seccomp: fix UAF in user-trap code
On the failure path, we do an fput() of the listener fd if the filter fails
to install (e.g. because of a TSYNC race that's lost, or if the thread is
killed, etc.). fput() doesn't actually release the fd, it just ads it to a
work queue. Then the thread proceeds to free the filter, even though the
listener struct file has a reference to it.

To fix this, on the failure path let's set the private data to null, so we
know in ->release() to ignore the filter.

Reported-by: syzbot+981c26489b2d1c6316ba@syzkaller.appspotmail.com
Fixes: 6a21cc50f0 ("seccomp: add a return code to trap to userspace")
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
2019-01-15 09:43:12 -08:00
Linus Torvalds
7939f8beec Andrea Righi fixed a NULL pointer dereference in trace_kprobe_create()
It is possible to trigger a NULL pointer dereference by writing an
 incorrectly formatted string to the krpobe_events file.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXD4L1RQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qsv7AP9nzekt94AQC2t5OQ38ph/nYGBjLc3T
 yLqFMshqUSgyVAEAgFB88fvniwLOMFyAqbfRb0+4mq1SDeThBY7TtJBzSQI=
 =+Pyh
 -----END PGP SIGNATURE-----

Merge tag 'trace-v5.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Andrea Righi fixed a NULL pointer dereference in trace_kprobe_create()

  It is possible to trigger a NULL pointer dereference by writing an
  incorrectly formatted string to the krpobe_events file"

* tag 'trace-v5.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()
2019-01-16 05:28:26 +12:00
Linus Torvalds
e8746440bf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix regression in multi-SKB responses to RTM_GETADDR, from Arthur
    Gautier.

 2) Fix ipv6 frag parsing in openvswitch, from Yi-Hung Wei.

 3) Unbounded recursion in ipv4 and ipv6 GUE tunnels, from Stefano
    Brivio.

 4) Use after free in hns driver, from Yonglong Liu.

 5) icmp6_send() needs to handle the case of NULL skb, from Eric
    Dumazet.

 6) Missing rcu read lock in __inet6_bind() when operating on mapped
    addresses, from David Ahern.

 7) Memory leak in tipc-nl_compat_publ_dump(), from Gustavo A. R. Silva.

 8) Fix PHY vs r8169 module loading ordering issues, from Heiner
    Kallweit.

 9) Fix bridge vlan memory leak, from Ido Schimmel.

10) Dev refcount leak in AF_PACKET, from Jason Gunthorpe.

11) Infoleak in ipv6_local_error(), flow label isn't completely
    initialized. From Eric Dumazet.

12) Handle mv88e6390 errata, from Andrew Lunn.

13) Making vhost/vsock CID hashing consistent, from Zha Bin.

14) Fix lack of UMH cleanup when it unexpectedly exits, from Taehee Yoo.

15) Bridge forwarding must clear skb->tstamp, from Paolo Abeni.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
  bnxt_en: Fix context memory allocation.
  bnxt_en: Fix ring checking logic on 57500 chips.
  mISDN: hfcsusb: Use struct_size() in kzalloc()
  net: clear skb->tstamp in bridge forwarding path
  net: bpfilter: disallow to remove bpfilter module while being used
  net: bpfilter: restart bpfilter_umh when error occurred
  net: bpfilter: use cleanup callback to release umh_info
  umh: add exit routine for UMH process
  isdn: i4l: isdn_tty: Fix some concurrency double-free bugs
  vhost/vsock: fix vhost vsock cid hashing inconsistent
  net: stmmac: Prevent RX starvation in stmmac_napi_poll()
  net: stmmac: Fix the logic of checking if RX Watchdog must be enabled
  net: stmmac: Check if CBS is supported before configuring
  net: stmmac: dwxgmac2: Only clear interrupts that are active
  net: stmmac: Fix PCI module removal leak
  tools/bpf: fix bpftool map dump with bitfields
  tools/bpf: test btf bitfield with >=256 struct member offset
  bpf: fix bpffs bitfield pretty print
  net: ethernet: mediatek: fix warning in phy_start_aneg
  tcp: change txhash on SYN-data timeout
  ...
2019-01-16 05:13:36 +12:00
Andrea Righi
8b05a3a750 tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()
It is possible to trigger a NULL pointer dereference by writing an
incorrectly formatted string to krpobe_events (trying to create a
kretprobe omitting the symbol).

Example:

 echo "r:event_1 " >> /sys/kernel/debug/tracing/kprobe_events

That triggers this:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 #PF error: [normal kernel read fault]
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP PTI
 CPU: 6 PID: 1757 Comm: bash Not tainted 5.0.0-rc1+ #125
 Hardware name: Dell Inc. XPS 13 9370/0F6P3V, BIOS 1.5.1 08/09/2018
 RIP: 0010:kstrtoull+0x2/0x20
 Code: 28 00 00 00 75 17 48 83 c4 18 5b 41 5c 5d c3 b8 ea ff ff ff eb e1 b8 de ff ff ff eb da e8 d6 36 bb ff 66 0f 1f 44 00 00 31 c0 <80> 3f 2b 55 48 89 e5 0f 94 c0 48 01 c7 e8 5c ff ff ff 5d c3 66 2e
 RSP: 0018:ffffb5d482e57cb8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82b12720
 RDX: ffffb5d482e57cf8 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffffb5d482e57d70 R08: ffffa0c05e5a7080 R09: ffffa0c05e003980
 R10: 0000000000000000 R11: 0000000040000000 R12: ffffa0c04fe87b08
 R13: 0000000000000001 R14: 000000000000000b R15: ffffa0c058d749e1
 FS:  00007f137c7f7740(0000) GS:ffffa0c05e580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000000497d46004 CR4: 00000000003606e0
 Call Trace:
  ? trace_kprobe_create+0xb6/0x840
  ? _cond_resched+0x19/0x40
  ? _cond_resched+0x19/0x40
  ? __kmalloc+0x62/0x210
  ? argv_split+0x8f/0x140
  ? trace_kprobe_create+0x840/0x840
  ? trace_kprobe_create+0x840/0x840
  create_or_delete_trace_kprobe+0x11/0x30
  trace_run_command+0x50/0x90
  trace_parse_run_command+0xc1/0x160
  probes_write+0x10/0x20
  __vfs_write+0x3a/0x1b0
  ? apparmor_file_permission+0x1a/0x20
  ? security_file_permission+0x31/0xf0
  ? _cond_resched+0x19/0x40
  vfs_write+0xb1/0x1a0
  ksys_write+0x55/0xc0
  __x64_sys_write+0x1a/0x20
  do_syscall_64+0x5a/0x120
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix by doing the proper argument checks in trace_kprobe_create().

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/lkml/20190111095108.b79a2ee026185cbd62365977@kernel.org
Link: http://lkml.kernel.org/r/20190111060113.GA22841@xps-13
Fixes: 6212dd2968 ("tracing/kprobes: Use dyn_event framework for kprobe events")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-15 11:33:45 -05:00
Thomas Gleixner
93ad0fc088 posix-cpu-timers: Unbreak timer rearming
The recent commit which prevented a division by 0 issue in the alarm timer
code broke posix CPU timers as an unwanted side effect.

The reason is that the common rearm code checks for timer->it_interval
being 0 now. What went unnoticed is that the posix cpu timer setup does not
initialize timer->it_interval as it stores the interval in CPU timer
specific storage. The reason for the separate storage is historical as the
posix CPU timers always had a 64bit nanoseconds representation internally
while timer->it_interval is type ktime_t which used to be a modified
timespec representation on 32bit machines.

Instead of reverting the offending commit and fixing the alarmtimer issue
in the alarmtimer code, store the interval in timer->it_interval at CPU
timer setup time so the common code check works. This also repairs the
existing inconistency of the posix CPU timer code which kept a single shot
timer armed despite of the interval being 0.

The separate storage can be removed in mainline, but that needs to be a
separate commit as the current one has to be backported to stable kernels.

Fixes: 0e334db6bb ("posix-timers: Fix division by zero bug")
Reported-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190111133500.840117406@linutronix.de
2019-01-15 16:34:37 +01:00
Srinivas Ramana
bddda606ec genirq: Make sure the initial affinity is not empty
If all CPUs in the irq_default_affinity mask are offline when an interrupt
is initialized then irq_setup_affinity() can set an empty affinity mask for
a newly allocated interrupt.

Fix this by falling back to cpu_online_mask in case the resulting affinity
mask is zero.

Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Link: https://lkml.kernel.org/r/1545312957-8504-1-git-send-email-sramana@codeaurora.org
2019-01-15 11:23:27 +01:00
Jonathan Neuschäfer
b7285b4253 kernel/sys.c: Clarify that UNAME26 does not generate unique versions anymore
UNAME26 is a mechanism to report Linux's version as 2.6.x, for
compatibility with old/broken software.  Due to the way it is
implemented, it would have to be updated after 5.0, to keep the
resulting versions unique.  Linus Torvalds argued:

 "Do we actually need this?

  I'd rather let it bitrot, and just let it return random versions. It
  will just start again at 2.4.60, won't it?

  Anybody who uses UNAME26 for a 5.x kernel might as well think it's
  still 4.x. The user space is so old that it can't possibly care about
  differences between 4.x and 5.x, can it?

  The only thing that matters is that it shows "2.4.<largeenough>",
  which it will do regardless"

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-14 10:38:03 +12:00
Taehee Yoo
73ab1cb2de umh: add exit routine for UMH process
A UMH process which is created by the fork_usermode_blob() such as
bpfilter needs to release members of the umh_info when process is
terminated.
But the do_exit() does not release members of the umh_info. hence module
which uses UMH needs own code to detect whether UMH process is
terminated or not.
But this implementation needs extra code for checking the status of
UMH process. it eventually makes the code more complex.

The new PF_UMH flag is added and it is used to identify UMH processes.
The exit_umh() does not release members of the umh_info.
Hence umh_info->cleanup callback should release both members of the
umh_info and the private data.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-11 18:05:40 -08:00
Yonghong Song
17e3ac8125 bpf: fix bpffs bitfield pretty print
Commit 9d5f9f701b ("bpf: btf: fix struct/union/fwd types
with kind_flag") introduced kind_flag and used bitfield_size
in the btf_member to directly pretty print member values.

The commit contained a bug where the incorrect parameters could be
passed to function btf_bitfield_seq_show(). The bits_offset
parameter in the function expects a value less than 8.
Instead, the member offset in the structure is passed.

The below is btf_bitfield_seq_show() func signature:
  void btf_bitfield_seq_show(void *data, u8 bits_offset,
                             u8 nr_bits, struct seq_file *m)
both bits_offset and nr_bits are u8 type. If the bitfield
member offset is greater than 256, incorrect value will
be printed.

This patch fixed the issue by calculating correct proper
data offset and bits_offset similar to non kind_flag case.

Fixes: 9d5f9f701b ("bpf: btf: fix struct/union/fwd types with kind_flag")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-11 10:40:54 +01:00
Song Liu
beaf3d1901 bpf: fix panic in stack_map_get_build_id() on i386 and arm32
As Naresh reported, test_stacktrace_build_id() causes panic on i386 and
arm32 systems. This is caused by page_address() returns NULL in certain
cases.

This patch fixes this error by using kmap_atomic/kunmap_atomic instead
of page_address.

Fixes: 615755a77b (" bpf: extend stackmap to save binary_build_id+offset instead of address")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-10 16:02:17 +01:00
Linus Torvalds
a88cc8da02 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "14 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, page_alloc: do not wake kswapd with zone lock held
  hugetlbfs: revert "use i_mmap_rwsem for more pmd sharing synchronization"
  hugetlbfs: revert "Use i_mmap_rwsem to fix page fault/truncate race"
  mm: page_mapped: don't assume compound page is huge or THP
  mm/memory.c: initialise mmu_notifier_range correctly
  tools/vm/page_owner: use page_owner_sort in the use example
  kasan: fix krealloc handling for tag-based mode
  kasan: make tag based mode work with CONFIG_HARDENED_USERCOPY
  kasan, arm64: use ARCH_SLAB_MINALIGN instead of manual aligning
  mm, memcg: fix reclaim deadlock with writeback
  mm/usercopy.c: no check page span for stack objects
  slab: alien caches must not be initialized if the allocation of the alien cache failed
  fork, memcg: fix cached_stacks case
  zram: idle writeback fixes and cleanup
2019-01-08 18:58:29 -08:00
Shakeel Butt
ba4a45746c fork, memcg: fix cached_stacks case
Commit 5eed6f1dff ("fork,memcg: fix crash in free_thread_stack on
memcg charge fail") fixes a crash caused due to failed memcg charge of
the kernel stack.  However the fix misses the cached_stacks case which
this patch fixes.  So, the same crash can happen if the memcg charge of
a cached stack is failed.

Link: http://lkml.kernel.org/r/20190102180145.57406-1-shakeelb@google.com
Fixes: 5eed6f1dff ("fork,memcg: fix crash in free_thread_stack on memcg charge fail")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-08 17:15:11 -08:00
David Herrmann
7b55851367 fork: record start_time late
This changes the fork(2) syscall to record the process start_time after
initializing the basic task structure but still before making the new
process visible to user-space.

Technically, we could record the start_time anytime during fork(2).  But
this might lead to scenarios where a start_time is recorded long before
a process becomes visible to user-space.  For instance, with
userfaultfd(2) and TLS, user-space can delay the execution of fork(2)
for an indefinite amount of time (and will, if this causes network
access, or similar).

By recording the start_time late, it much closer reflects the point in
time where the process becomes live and can be observed by other
processes.

Lastly, this makes it much harder for user-space to predict and control
the start_time they get assigned.  Previously, user-space could fork a
process and stall it in copy_thread_tls() before its pid is allocated,
but after its start_time is recorded.  This can be misused to later-on
cycle through PIDs and resume the stalled fork(2) yielding a process
that has the same pid and start_time as a process that existed before.
This can be used to circumvent security systems that identify processes
by their pid+start_time combination.

Even though user-space was always aware that start_time recording is
flaky (but several projects are known to still rely on start_time-based
identification), changing the start_time to be recorded late will help
mitigate existing attacks and make it much harder for user-space to
control the start_time a process gets assigned.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-08 09:40:53 -08:00
Linus Torvalds
85e1ffbd42 Kbuild late updates for v4.21
- improve boolinit.cocci and use_after_iter.cocci semantic patches
 
 - fix alignment for kallsyms
 
 - move 'asm goto' compiler test to Kconfig and clean up jump_label
   CONFIG option
 
 - generate asm-generic wrappers automatically if arch does not implement
   mandatory UAPI headers
 
 - remove redundant generic-y defines
 
 - misc cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcMV5GAAoJED2LAQed4NsGs9gQAI/oGg8wJgk9a7+dJCX245W5
 F4ReftnQd4AFptFCi9geJkr+sfViXNgwPLqlJxiXz8Qe8XP7z3LcArDw3FUzwvGn
 bMSBiN9ggwWkOFgF523XesYgUVtcLpkNch/Migzf1Ac0FHk0G9o7gjcdsvAWHkUu
 qFwtNcUB6PElRbhsHsh5qCY1/6HaAXgf/7O7wztnaKRe9myN6f2HzT4wANS9HHde
 1e1r0LcIQeGWfG+3va3fZl6SDxSI/ybl244OcDmDyYl6RA1skSDlHbIBIFgUPoS0
 cLyzoVj+GkfI1fRFEIfou+dj7lpukoAXHsggHo0M+ofqtbMF+VB2T3jvg4txanCP
 TXzDc+04QUguK5yVnBfcnyC64Htrhnbq0eGy43kd1VZWAEGApl+680P8CRsWU3ZV
 kOiFvZQ6RP/Ssw+a42yU3SHr31WD7feuQqHU65osQt4rdyL5wnrfU1vaUvJSkltF
 cyPr9Kz/Ism0kPodhpFkuKxwtlKOw6/uwdCQoQHtxAPkvkcydhYx93x3iE0nxObS
 CRMximiRyE12DOcv/3uv69n0JOPn6AsITcMNp8XryASYrR2/52txhGKGhvo3+Zoq
 5pwc063JsuxJ/5/dcOw/erQar5d1eBRaBJyEWnXroxUjbsLPAznE+UIN8tmvyVly
 SunlxNOXBdYeWN6t6S3H
 =I+r6
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v4.21-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - improve boolinit.cocci and use_after_iter.cocci semantic patches

 - fix alignment for kallsyms

 - move 'asm goto' compiler test to Kconfig and clean up jump_label
   CONFIG option

 - generate asm-generic wrappers automatically if arch does not
   implement mandatory UAPI headers

 - remove redundant generic-y defines

 - misc cleanups

* tag 'kbuild-v4.21-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: rename generated .*conf-cfg to *conf-cfg
  kbuild: remove unnecessary stubs for archheader and archscripts
  kbuild: use assignment instead of define ... endef for filechk_* rules
  arch: remove redundant UAPI generic-y defines
  kbuild: generate asm-generic wrappers if mandatory headers are missing
  arch: remove stale comments "UAPI Header export list"
  riscv: remove redundant kernel-space generic-y
  kbuild: change filechk to surround the given command with { }
  kbuild: remove redundant target cleaning on failure
  kbuild: clean up rule_dtc_dt_yaml
  kbuild: remove UIMAGE_IN and UIMAGE_OUT
  jump_label: move 'asm goto' support test to Kconfig
  kallsyms: lower alignment on ARM
  scripts: coccinelle: boolinit: drop warnings on named constants
  scripts: coccinelle: check for redeclaration
  kconfig: remove unused "file" field of yylval union
  nds32: remove redundant kernel-space generic-y
  nios2: remove unneeded HAS_DMA define
2019-01-06 16:33:10 -08:00
Linus Torvalds
e2b745f469 dma-mapping fixes for Linux 4.21-rc1
Fix various regressions introduced in this cycles:
 
  - fix dma-debug tracking for the map_page / map_single consolidatation
  - properly stub out DMA mapping symbols for !HAS_DMA builds to avoid
    link failures
  - fix AMD Gart direct mappings
  - setup the dma address for no kernel mappings using the remap
    allocator
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAlwyR9ULHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYPvOA/+L+32p2pm8o6NTgvtRvqsKNrbOm02fORLrhBqAiok
 AcirFDxTfMuUWU2isr7E7WNqwEmUQ1nVUa+I0IJ/IJFfKdTggXcaTX1M19+62KWa
 1LHpZLg1t2rl2yFQHgTrFKr5sz1PwUKZO8UbrYaYYgLgQkWDRzJs4E/tFNju8pMm
 0Usexo/bkI5mreJBImMsFwAnuk0k3NT058XIeD+eNttKjcuz5kEH+bE/999vySW3
 sOj9Peic/EFelOGb4ODxUIPjhiGFMv5dVusSAsFBH26iwQfX/tFSmXhrI5cnDewg
 NlREennfyM+6uTH/DO+BlX7eGCRYbFc1GU5H9q4rRMXhEam6oc2AzVKuElJOVstZ
 XVjP6zTwmuOh/5ff0NG6EPjA/OFcmlBEsmeWu4xSS8KsNILOkpUaPed/uWnA7O+2
 mvU104NA5cHgVMgiGNM/4ilirkEZEFEHYhafH42bQxjMigm7ZHN14NtwM7StLTu6
 QgyfPUcW/LmHj2scgvB1AZ+iQX0z7yJJMGifUxtz+eMCWCC7neOJ7JLvNnS9WI5w
 9RwYaCOcDAZyAmCpbSADWxeG9cfsCDp8wmaGs3YVyhkDU8tCSqbxWJutvyDQnC17
 GtZ0vYLTaJXBCq1L/FC0y8NCCGgvySPXYU7/ZYuOCzS4q2jvjwTWD3dKodvnS+mb
 B0s=
 =H9J6
 -----END PGP SIGNATURE-----

Merge tag 'dma-mapping-4.21-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:
 "Fix various regressions introduced in this cycles:

   - fix dma-debug tracking for the map_page / map_single
     consolidatation

   - properly stub out DMA mapping symbols for !HAS_DMA builds to avoid
     link failures

   - fix AMD Gart direct mappings

   - setup the dma address for no kernel mappings using the remap
     allocator"

* tag 'dma-mapping-4.21-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-direct: fix DMA_ATTR_NO_KERNEL_MAPPING for remapped allocations
  x86/amd_gart: fix unmapping of non-GART mappings
  dma-mapping: remove a few unused exports
  dma-mapping: properly stub out the DMA API for !CONFIG_HAS_DMA
  dma-mapping: remove dmam_{declare,release}_coherent_memory
  dma-mapping: implement dmam_alloc_coherent using dmam_alloc_attrs
  dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs
2019-01-06 11:47:26 -08:00
Daniel Borkmann
d3bd7413e0 bpf: fix sanitation of alu op with pointer / scalar type from different paths
While 979d63d50c ("bpf: prevent out of bounds speculation on pointer
arithmetic") took care of rejecting alu op on pointer when e.g. pointer
came from two different map values with different map properties such as
value size, Jann reported that a case was not covered yet when a given
alu op is used in both "ptr_reg += reg" and "numeric_reg += reg" from
different branches where we would incorrectly try to sanitize based
on the pointer's limit. Catch this corner case and reject the program
instead.

Fixes: 979d63d50c ("bpf: prevent out of bounds speculation on pointer arithmetic")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-05 21:32:38 -08:00