Commit Graph

22625 Commits

Author SHA1 Message Date
Tao Huang
04026c23c8 Merge branch 'linux-linaro-lsk-v4.4-android' of git://git.linaro.org/kernel/linux-linaro-stable.git
* linux-linaro-lsk-v4.4-android: (812 commits)
  Linux 4.4.167
  mac80211: ignore NullFunc frames in the duplicate detection
  mac80211: fix reordering of buffered broadcast packets
  mac80211: ignore tx status for PS stations in ieee80211_tx_status_ext
  mac80211: Clear beacon_int in ieee80211_do_stop
  mac80211_hwsim: Timer should be initialized before device registered
  kgdboc: fix KASAN global-out-of-bounds bug in param_set_kgdboc_var()
  tty: serial: 8250_mtk: always resume the device in probe.
  cifs: Fix separator when building path from dentry
  Staging: lustre: remove two build warnings
  xhci: Prevent U1/U2 link pm states if exit latency is too long
  SUNRPC: Fix leak of krb5p encode pages
  virtio/s390: fix race in ccw_io_helper()
  virtio/s390: avoid race on vcdev->config
  ALSA: pcm: Fix interval evaluation with openmin/max
  ALSA: pcm: Call snd_pcm_unlink() conditionally at closing
  ALSA: pcm: Fix starvation on down_write_nonblock()
  ALSA: hda: Add support for AMD Stoney Ridge
  ALSA: usb-audio: Fix UAF decrement if card has no live interfaces in card.c
  USB: check usb_get_extra_descriptor for proper size
  ...

Conflicts:
	drivers/gpu/drm/rockchip/rockchip_drm_drv.c
	drivers/usb/host/xhci-ring.c

Change-Id: I4304b0875908403a7d88a0d77da52cea04563c11
2018-12-19 18:46:58 +08:00
Mark Brown
b6b5ee6576 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2018-12-14 11:52:31 +00:00
Mark Brown
5f783fd0a8 Merge tag 'v4.4.167' into linux-linaro-lsk-v4.4
This is the 4.4.167 stable release
2018-12-14 11:11:33 +00:00
Andrea Parri
c9271209b6 uprobes: Fix handle_swbp() vs. unregister() + register() race once more
commit 09d3f015d1 upstream.

Commit:

  142b18ddc8 ("uprobes: Fix handle_swbp() vs unregister() + register() race")

added the UPROBE_COPY_INSN flag, and corresponding smp_wmb() and smp_rmb()
memory barriers, to ensure that handle_swbp() uses fully-initialized
uprobes only.

However, the smp_rmb() is mis-placed: this barrier should be placed
after handle_swbp() has tested for the flag, thus guaranteeing that
(program-order) subsequent loads from the uprobe can see the initial
stores performed by prepare_uprobe().

Move the smp_rmb() accordingly.  Also amend the comments associated
to the two memory barriers to indicate their actual locations.

Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@kernel.org
Fixes: 142b18ddc8 ("uprobes: Fix handle_swbp() vs unregister() + register() race")
Link: http://lkml.kernel.org/r/20181122161031.15179-1-andrea.parri@amarulasolutions.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-13 09:21:29 +01:00
Arnd Bergmann
e1885163d5 kdb: use memmove instead of overlapping memcpy
commit 2cf2f0d5b9 upstream.

gcc discovered that the memcpy() arguments in kdbnearsym() overlap, so
we should really use memmove(), which is defined to handle that correctly:

In function 'memcpy',
    inlined from 'kdbnearsym' at /git/arm-soc/kernel/debug/kdb/kdb_support.c:132:4:
/git/arm-soc/include/linux/string.h:353:9: error: '__builtin_memcpy' accessing 792 bytes at offsets 0 and 8 overlaps 784 bytes at offset 8 [-Werror=restrict]
  return __builtin_memcpy(p, q, size);

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-13 09:21:29 +01:00
Amit Pundir
770f7163da Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
* linux-linaro-lsk-v4.4: (622 commits)
  Linux 4.4.166
  drm/ast: Remove existing framebuffers before loading driver
  s390/mm: Check for valid vma before zapping in gmap_discard
  namei: allow restricted O_CREAT of FIFOs and regular files
  sched/core: Allow __sched_setscheduler() in interrupts when PI is not used
  btrfs: Ensure btrfs_trim_fs can trim the whole filesystem
  usb: xhci: fix uninitialized completion when USB3 port got wrong status
  tty: wipe buffer if not echoing data
  tty: wipe buffer.
  iwlwifi: mvm: fix regulatory domain update when the firmware starts
  scsi: qla2xxx: do not queue commands when unloading
  scsi: ufshcd: release resources if probe fails
  scsi: ufs: fix race between clock gating and devfreq scaling work
  scsi: ufshcd: Fix race between clk scaling and ungate work
  scsi: ufs: fix bugs related to null pointer access and array size
  netfilter: nf_tables: fix oops when inserting an element into a verdict map
  mwifiex: fix p2p device doesn't find in scan problem
  mwifiex: Fix NULL pointer dereference in skb_dequeue()
  cw1200: Don't leak memory if krealloc failes
  Input: xpad - add support for Xbox1 PDP Camo series gamepad
  ...

  Conflicts:
    Makefile
    arch/x86/Makefile
    drivers/base/power/main.c
    drivers/block/zram/zram_drv.c
    kernel/debug/kdb/kdb_io.c
    net/ipv6/route.c
    scripts/Kbuild.include
      Conflicts in above files are fixed as done in AOSP Change-Id:
      I5bd20327e0c1139c46f74e8d5916fa0530a307d3 ("Merge 4.4.165 into android-4.4").

    arch/arm64/include/asm/cpufeature.h
    arch/arm64/kernel/cpufeature.c
      Conflicts in above files is due to AOSP Change-Id:
      I11cb874d12a7d0921f452c62b0752e0028a8e0a7 ("FROMLIST: arm64: entry: Add
      fake CPU feature for unmapping the kernel at EL0"), which needed a minor
      rebasing.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-12-11 00:07:21 +05:30
Kees Cook
aa8893750a UPSTREAM: seccomp: Fix tracer exit notifications during fatal signals
This fixes a ptrace vs fatal pending signals bug as manifested in
seccomp now that seccomp was reordered to happen after ptrace. The
short version is that seccomp should not attempt to call do_exit()
while fatal signals are pending under a tracer. The existing code was
trying to be as defensively paranoid as possible, but it now ends up
confusing ptrace. Instead, the syscall can just be skipped (which solves
the original concern that the do_exit() was addressing) and normal signal
handling, tracer notification, and process death can happen.

Paraphrasing from the original bug report:

If a tracee task is in a PTRACE_EVENT_SECCOMP trap, or has been resumed
after such a trap but not yet been scheduled, and another task in the
thread-group calls exit_group(), then the tracee task exits without the
ptracer receiving a PTRACE_EVENT_EXIT notification. Test case here:
https://gist.github.com/khuey/3c43ac247c72cef8c956ca73281c9be7

The bug happens because when __seccomp_filter() detects
fatal_signal_pending(), it calls do_exit() without dequeuing the fatal
signal. When do_exit() sends the PTRACE_EVENT_EXIT notification and
that task is descheduled, __schedule() notices that there is a fatal
signal pending and changes its state from TASK_TRACED to TASK_RUNNING.
That prevents the ptracer's waitpid() from returning the ptrace event.
A more detailed analysis is here:
https://github.com/mozilla/rr/issues/1762#issuecomment-237396255.

Reported-by: Robert O'Callahan <robert@ocallahan.org>
Reported-by: Kyle Huey <khuey@kylehuey.com>
Tested-by: Kyle Huey <khuey@kylehuey.com>
Fixes: 93e35efb8d ("x86/ptrace: run seccomp after ptrace")
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
(cherry picked from commit 485a252a55)

Bug: 119769499
Change-Id: I444e69093e88d58587b4d5c4f2d777985591c32d
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-12-10 23:47:10 +05:30
Kees Cook
9cf8a2391a UPSTREAM: seccomp: recheck the syscall after RET_TRACE
When RET_TRACE triggers, a tracer may change a syscall into something that
should be filtered by seccomp. This re-runs seccomp after a trace event
to make sure things continue to pass.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
(cherry picked from commit ce6526e8af)

Bug: 119769499
Change-Id: Ib67732df3c2ac8c6b1de87e75f96aaed02f4627d
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-12-10 23:46:31 +05:30
Kees Cook
ceb1e1cda7 UPSTREAM: seccomp: remove 2-phase API
Since nothing is using the 2-phase API, and it adds more complexity than
benefit, remove it.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
(cherry picked from commit 8112c4f140)

Bug: 119769499
Change-Id: Iff6246c1e6e9dd0161b80b666a5e796f78a5c785
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-12-10 23:46:22 +05:30
Andy Lutomirski
ec8e12f60f BACKPORT: seccomp: Add a seccomp_data parameter secure_computing()
Currently, if arch code wants to supply seccomp_data directly to
seccomp (which is generally much faster than having seccomp do it
using the syscall_get_xyz() API), it has to use the two-phase
seccomp hooks. Add it to the easy hooks, too.

Cc: linux-arch@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit 2f275de5d1)

Bug: 119769499
Change-Id: I96876ecd8d1743c289ecef6d2deb65361d1f5baa
[ghackmann@google.com: drop changes to parisc, tile, and um, which
 didn't implement seccomp support in this kernel version]
Signed-off-by: Greg Hackmann <ghackmann@google.com>

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-12-10 23:46:03 +05:30
Mark Brown
684d5e05df Merge tag 'v4.4.166' into linux-linaro-lsk-v4.4
This is the 4.4.166 stable release
2018-12-04 10:49:55 +00:00
Salvatore Mesoraca
3658ccbbac namei: allow restricted O_CREAT of FIFOs and regular files
commit 30aba6656f upstream.

Disallows open of FIFOs or regular files not owned by the user in world
writable sticky directories, unless the owner is the same as that of the
directory or the file is opened without the O_CREAT flag.  The purpose
is to make data spoofing attacks harder.  This protection can be turned
on and off separately for FIFOs and regular files via sysctl, just like
the symlinks/hardlinks protection.  This patch is based on Openwall's
"HARDEN_FIFO" feature by Solar Designer.

This is a brief list of old vulnerabilities that could have been prevented
by this feature, some of them even allow for privilege escalation:

CVE-2000-1134
CVE-2007-3852
CVE-2008-0525
CVE-2009-0416
CVE-2011-4834
CVE-2015-1838
CVE-2015-7442
CVE-2016-7489

This list is not meant to be complete.  It's difficult to track down all
vulnerabilities of this kind because they were often reported without any
mention of this particular attack vector.  In fact, before
hardlinks/symlinks restrictions, fifos/regular files weren't the favorite
vehicle to exploit them.

[s.mesoraca16@gmail.com: fix bug reported by Dan Carpenter]
  Link: https://lkml.kernel.org/r/20180426081456.GA7060@mwanda
  Link: http://lkml.kernel.org/r/1524829819-11275-1-git-send-email-s.mesoraca16@gmail.com
[keescook@chromium.org: drop pr_warn_ratelimited() in favor of audit changes in the future]
[keescook@chromium.org: adjust commit subjet]
Link: http://lkml.kernel.org/r/20180416175918.GA13494@beast
Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Solar Designer <solar@openwall.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Loic <hackurx@opensec.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-01 09:46:41 +01:00
Steven Rostedt (VMware)
4f29112ec9 sched/core: Allow __sched_setscheduler() in interrupts when PI is not used
commit 896bbb2522 upstream.

When priority inheritance was added back in 2.6.18 to sched_setscheduler(), it
added a path to taking an rt-mutex wait_lock, which is not IRQ safe. As PI
is not a common occurrence, lockdep will likely never trigger if
sched_setscheduler was called from interrupt context. A BUG_ON() was added
to trigger if __sched_setscheduler() was ever called from interrupt context
because there was a possibility to take the wait_lock.

Today the wait_lock is irq safe, but the path to taking it in
sched_setscheduler() is the same as the path to taking it from normal
context. The wait_lock is taken with raw_spin_lock_irq() and released with
raw_spin_unlock_irq() which will indiscriminately enable interrupts,
which would be bad in interrupt context.

The problem is that normalize_rt_tasks, which is called by triggering the
sysrq nice-all-RT-tasks was changed to call __sched_setscheduler(), and this
is done from interrupt context!

Now __sched_setscheduler() takes a "pi" parameter that is used to know if
the priority inheritance should be called or not. As the BUG_ON() only cares
about calling the PI code, it should only bug if called from interrupt
context with the "pi" parameter set to true.

Reported-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Tested-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: dbc7f069b9 ("sched: Use replace normalize_task() with __sched_setscheduler()")
Link: http://lkml.kernel.org/r/20170308124654.10e598f2@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-01 09:46:41 +01:00
Prarit Bhargava
a4cfd4595d kdb: Use strscpy with destination buffer size
[ Upstream commit c2b94c72d9 ]

gcc 8.1.0 warns with:

kernel/debug/kdb/kdb_support.c: In function ‘kallsyms_symbol_next’:
kernel/debug/kdb/kdb_support.c:239:4: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
     strncpy(prefix_name, name, strlen(name)+1);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/debug/kdb/kdb_support.c:239:31: note: length computed here

Use strscpy() with the destination buffer size, and use ellipses when
displaying truncated symbols.

v2: Use strscpy()

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Toppins <jtoppins@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: kgdb-bugreport@lists.sourceforge.net
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-01 09:46:35 +01:00
Mark Brown
375fef4f04 Merge tag 'v4.4.164' into linux-linaro-lsk-v4.4
This is the 4.4.164 stable release
2018-11-22 15:19:34 +00:00
Lukas Wunner
59ba12331e genirq: Fix race on spurious interrupt detection
commit 746a923b86 upstream.

Commit 1e77d0a1ed ("genirq: Sanitize spurious interrupt detection of
threaded irqs") made detection of spurious interrupts work for threaded
handlers by:

a) incrementing a counter every time the thread returns IRQ_HANDLED, and
b) checking whether that counter has increased every time the thread is
   woken.

However for oneshot interrupts, the commit unmasks the interrupt before
incrementing the counter.  If another interrupt occurs right after
unmasking but before the counter is incremented, that interrupt is
incorrectly considered spurious:

time
 |  irq_thread()
 |    irq_thread_fn()
 |      action->thread_fn()
 |      irq_finalize_oneshot()
 |        unmask_threaded_irq()            /* interrupt is unmasked */
 |
 |                  /* interrupt fires, incorrectly deemed spurious */
 |
 |    atomic_inc(&desc->threads_handled); /* counter is incremented */
 v

This is observed with a hi3110 CAN controller receiving data at high volume
(from a separate machine sending with "cangen -g 0 -i -x"): The controller
signals a huge number of interrupts (hundreds of millions per day) and
every second there are about a dozen which are deemed spurious.

In theory with high CPU load and the presence of higher priority tasks, the
number of incorrectly detected spurious interrupts might increase beyond
the 99,900 threshold and cause disablement of the interrupt.

In practice it just increments the spurious interrupt count. But that can
cause people to waste time investigating it over and over.

Fix it by moving the accounting before the invocation of
irq_finalize_oneshot().

[ tglx: Folded change log update ]

Fixes: 1e77d0a1ed ("genirq: Sanitize spurious interrupt detection of threaded irqs")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Akshay Bhat <akshay.bhat@timesys.com>
Cc: Casey Fitzpatrick <casey.fitzpatrick@timesys.com>
Cc: stable@vger.kernel.org # v3.16+
Link: https://lkml.kernel.org/r/1dfd8bbd16163940648045495e3e9698e63b50ad.1539867047.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
He Zhe
d24a12ef98 printk: Fix panic caused by passing log_buf_len to command line
commit 277fcdb2cf upstream.

log_buf_len_setup does not check input argument before passing it to
simple_strtoull. The argument would be a NULL pointer if "log_buf_len",
without its value, is set in command line and thus causes the following
panic.

PANIC: early exception 0xe3 IP 10:ffffffffaaeacd0d error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc4-yocto-standard+ #1
[    0.000000] RIP: 0010:_parse_integer_fixup_radix+0xd/0x70
...
[    0.000000] Call Trace:
[    0.000000]  simple_strtoull+0x29/0x70
[    0.000000]  memparse+0x26/0x90
[    0.000000]  log_buf_len_setup+0x17/0x22
[    0.000000]  do_early_param+0x57/0x8e
[    0.000000]  parse_args+0x208/0x320
[    0.000000]  ? rdinit_setup+0x30/0x30
[    0.000000]  parse_early_options+0x29/0x2d
[    0.000000]  ? rdinit_setup+0x30/0x30
[    0.000000]  parse_early_param+0x36/0x4d
[    0.000000]  setup_arch+0x336/0x99e
[    0.000000]  start_kernel+0x6f/0x4ee
[    0.000000]  x86_64_start_reservations+0x24/0x26
[    0.000000]  x86_64_start_kernel+0x6f/0x72
[    0.000000]  secondary_startup_64+0xa4/0xb0

This patch adds a check to prevent the panic.

Link: http://lkml.kernel.org/r/1538239553-81805-1-git-send-email-zhe.he@windriver.com
Cc: stable@vger.kernel.org
Cc: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
Arnd Bergmann
52458d09b5 kbuild: fix kernel/bounds.c 'W=1' warning
commit 6a32c2469c upstream.

Building any configuration with 'make W=1' produces a warning:

kernel/bounds.c:16:6: warning: no previous prototype for 'foo' [-Wmissing-prototypes]

When also passing -Werror, this prevents us from building any other files.
Nobody ever calls the function, but we can't make it 'static' either
since we want the compiler output.

Calling it 'main' instead however avoids the warning, because gcc
does not insist on having a declaration for main.

Link: http://lkml.kernel.org/r/20181005083313.2088252-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
Eric W. Biederman
9ab9fc44d3 signal: Always deliver the kernel's SIGKILL and SIGSTOP to a pid namespace init
[ Upstream commit 3597dfe01d ]

Instead of playing whack-a-mole and changing SEND_SIG_PRIV to
SEND_SIG_FORCED throughout the kernel to ensure a pid namespace init
gets signals sent by the kernel, stop allowing a pid namespace init to
ignore SIGKILL or SIGSTOP sent by the kernel.  A pid namespace init is
only supposed to be able to ignore signals sent from itself and
children with SIG_DFL.

Fixes: 921cf9f630 ("signals: protect cinit from unblocked SIG_DFL signals")
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:33 +01:00
Masami Hiramatsu
0524e92e0f kprobes: Return error if we fail to reuse kprobe instead of BUG_ON()
[ Upstream commit 819319fc93 ]

Make reuse_unused_kprobe() to return error code if
it fails to reuse unused kprobe for optprobe instead
of calling BUG_ON().

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>
Link: http://lkml.kernel.org/r/153666124040.21306.14150398706331307654.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:32 +01:00
Waiman Long
ef42ef8451 locking/lockdep: Fix debug_locks off performance problem
[ Upstream commit 9506a7425b ]

It was found that when debug_locks was turned off because of a problem
found by the lockdep code, the system performance could drop quite
significantly when the lock_stat code was also configured into the
kernel. For instance, parallel kernel build time on a 4-socket x86-64
server nearly doubled.

Further analysis into the cause of the slowdown traced back to the
frequent call to debug_locks_off() from the __lock_acquired() function
probably due to some inconsistent lockdep states with debug_locks
off. The debug_locks_off() function did an unconditional atomic xchg
to write a 0 value into debug_locks which had already been set to 0.
This led to severe cacheline contention in the cacheline that held
debug_locks.  As debug_locks is being referenced in quite a few different
places in the kernel, this greatly slow down the system performance.

To prevent that trashing of debug_locks cacheline, lock_acquired()
and lock_contended() now checks the state of debug_locks before
proceeding. The debug_locks_off() function is also modified to check
debug_locks before calling __debug_locks_off().

Signed-off-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>
Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:31 +01:00
Mark Brown
e0745aa91b Merge tag 'v4.4.163' into linux-linaro-lsk-v4.4
This is the 4.4.163 stable release
2018-11-13 09:21:06 -08:00
Catalin Marinas
8a1d3de19b cpuidle: Do not access cpuidle_devices when !CONFIG_CPU_IDLE
commit 9bd616e3db upstream.

The cpuidle_devices per-CPU variable is only defined when CPU_IDLE is
enabled. Commit c8cc7d4de7 ("sched/idle: Reorganize the idle loop")
removed the #ifdef CONFIG_CPU_IDLE around cpuidle_idle_call() with the
compiler optimising away __this_cpu_read(cpuidle_devices). However, with
CONFIG_UBSAN && !CONFIG_CPU_IDLE, this optimisation no longer happens
and the kernel fails to link since cpuidle_devices is not defined.

This patch introduces an accessor function for the current CPU cpuidle
device (returning NULL when !CONFIG_CPU_IDLE) and uses it in
cpuidle_idle_call().

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: 4.5+ <stable@vger.kernel.org> # 4.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10 07:41:43 -08:00
Phil Auld
4a2b54a750 sched/fair: Fix throttle_list starvation with low CFS quota
commit baa9be4ffb upstream.

With a very low cpu.cfs_quota_us setting, such as the minimum of 1000,
distribute_cfs_runtime may not empty the throttled_list before it runs
out of runtime to distribute. In that case, due to the change from
c06f04c704 to put throttled entries at the head of the list, later entries
on the list will starve.  Essentially, the same X processes will get pulled
off the list, given CPU time and then, when expired, get put back on the
head of the list where distribute_cfs_runtime will give runtime to the same
set of processes leaving the rest.

Fix the issue by setting a bit in struct cfs_bandwidth when
distribute_cfs_runtime is running, so that the code in throttle_cfs_rq can
decide to put the throttled entry on the tail or the head of the list.  The
bit is set/cleared by the callers of distribute_cfs_runtime while they hold
cfs_bandwidth->lock.

This is easy to reproduce with a handful of CPU consumers. I use 'crash' on
the live system. In some cases you can simply look at the throttled list and
see the later entries are not changing:

  crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1"  "$4}' | pr -t -n3
    1     ffff90b56cb2d200  -976050
    2     ffff90b56cb2cc00  -484925
    3     ffff90b56cb2bc00  -658814
    4     ffff90b56cb2ba00  -275365
    5     ffff90b166a45600  -135138
    6     ffff90b56cb2da00  -282505
    7     ffff90b56cb2e000  -148065
    8     ffff90b56cb2fa00  -872591
    9     ffff90b56cb2c000  -84687
   10     ffff90b56cb2f000  -87237
   11     ffff90b166a40a00  -164582

  crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1"  "$4}' | pr -t -n3
    1     ffff90b56cb2d200  -994147
    2     ffff90b56cb2cc00  -306051
    3     ffff90b56cb2bc00  -961321
    4     ffff90b56cb2ba00  -24490
    5     ffff90b166a45600  -135138
    6     ffff90b56cb2da00  -282505
    7     ffff90b56cb2e000  -148065
    8     ffff90b56cb2fa00  -872591
    9     ffff90b56cb2c000  -84687
   10     ffff90b56cb2f000  -87237
   11     ffff90b166a40a00  -164582

Sometimes it is easier to see by finding a process getting starved and looking
at the sched_info:

  crash> task ffff8eb765994500 sched_info
  PID: 7800   TASK: ffff8eb765994500  CPU: 16  COMMAND: "cputest"
    sched_info = {
      pcount = 8,
      run_delay = 697094208,
      last_arrival = 240260125039,
      last_queued = 240260327513
    },
  crash> task ffff8eb765994500 sched_info
  PID: 7800   TASK: ffff8eb765994500  CPU: 16  COMMAND: "cputest"
    sched_info = {
      pcount = 8,
      run_delay = 697094208,
      last_arrival = 240260125039,
      last_queued = 240260327513
    },

Signed-off-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: c06f04c704 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop")
Link: http://lkml.kernel.org/r/20181008143639.GA4019@pauld.bos.csb
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10 07:41:43 -08:00
Daniel Borkmann
e25dc63aa3 bpf: generally move prog destruction to RCU deferral
[ Upstream commit 1aacde3d22 ]

Jann Horn reported following analysis that could potentially result
in a very hard to trigger (if not impossible) UAF race, to quote his
event timeline:

 - Set up a process with threads T1, T2 and T3
 - Let T1 set up a socket filter F1 that invokes another filter F2
   through a BPF map [tail call]
 - Let T1 trigger the socket filter via a unix domain socket write,
   don't wait for completion
 - Let T2 call PERF_EVENT_IOC_SET_BPF with F2, don't wait for completion
 - Now T2 should be behind bpf_prog_get(), but before bpf_prog_put()
 - Let T3 close the file descriptor for F2, dropping the reference
   count of F2 to 2
 - At this point, T1 should have looked up F2 from the map, but not
   finished executing it
 - Let T3 remove F2 from the BPF map, dropping the reference count of
   F2 to 1
 - Now T2 should call bpf_prog_put() (wrong BPF program type), dropping
   the reference count of F2 to 0 and scheduling bpf_prog_free_deferred()
   via schedule_work()
 - At this point, the BPF program could be freed
 - BPF execution is still running in a freed BPF program

While at PERF_EVENT_IOC_SET_BPF time it's only guaranteed that the perf
event fd we're doing the syscall on doesn't disappear from underneath us
for whole syscall time, it may not be the case for the bpf fd used as
an argument only after we did the put. It needs to be a valid fd pointing
to a BPF program at the time of the call to make the bpf_prog_get() and
while T2 gets preempted, F2 must have dropped reference to 1 on the other
CPU. The fput() from the close() in T3 should also add additionally delay
to the reference drop via exit_task_work() when bpf_prog_release() gets
called as well as scheduling bpf_prog_free_deferred().

That said, it makes nevertheless sense to move the BPF prog destruction
generally after RCU grace period to guarantee that such scenario above,
but also others as recently fixed in ceb5607035 ("bpf, perf: delay release
of BPF prog after grace period") with regards to tail calls won't happen.
Integrating bpf_prog_free_deferred() directly into the RCU callback is
not allowed since the invocation might happen from either softirq or
process context, so we're not permitted to block. Reviewing all bpf_prog_put()
invocations from eBPF side (note, cBPF -> eBPF progs don't use this for
their destruction) with call_rcu() look good to me.

Since we don't know whether at the time of attaching the program, we're
already part of a tail call map, we need to use RCU variant. However, due
to this, there won't be severely more stress on the RCU callback queue:
situations with above bpf_prog_get() and bpf_prog_put() combo in practice
normally won't lead to releases, but even if they would, enough effort/
cycles have to be put into loading a BPF program into the kernel already.

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: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:37 -08:00
Alexander Shishkin
5796c70e5b perf/core: Don't leak event in the syscall error path
[ Upstream commit 201c2f85bd ]

In the error path, event_file not being NULL is used to determine
whether the event itself still needs to be free'd, so fix it up to
avoid leaking.

Reported-by: Leon Yu <chianglungyu@gmail.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 130056275a ("perf: Do not double free")
Link: http://lkml.kernel.org/r/87twk06yxp.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:36 -08:00
Peter Zijlstra
137b1ce318 sched/cgroup: Fix cgroup entity load tracking tear-down
[ Upstream commit 6fe1f348b3 ]

When a cgroup's CPU runqueue is destroyed, it should remove its
remaining load accounting from its parent cgroup.

The current site for doing so it unsuited because its far too late and
unordered against other cgroup removal (->css_free() will be, but we're also
in an RCU callback).

Put it in the ->css_offline() callback, which is the start of cgroup
destruction, right after the group has been made unavailable to
userspace. The ->css_offline() callbacks are called in hierarchical order
after the following v4.4 commit:

  aa226ff4a1 ("cgroup: make sure a parent css isn't offlined before its children")

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160121212416.GL6357@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:35 -08:00
Steven Rostedt (Red Hat)
70b3d6c5aa tracing: Skip more functions when doing stack tracing of events
[ Upstream commit be54f69c26 ]

 # echo 1 > options/stacktrace
 # echo 1 > events/sched/sched_switch/enable
 # cat trace
          <idle>-0     [002] d..2  1982.525169: <stack trace>
 => save_stack_trace
 => __ftrace_trace_stack
 => trace_buffer_unlock_commit_regs
 => event_trigger_unlock_commit
 => trace_event_buffer_commit
 => trace_event_raw_event_sched_switch
 => __schedule
 => schedule
 => schedule_preempt_disabled
 => cpu_startup_entry
 => start_secondary

The above shows that we are seeing 6 functions before ever making it to the
caller of the sched_switch event.

 # echo stacktrace > events/sched/sched_switch/trigger
 # cat trace
          <idle>-0     [002] d..3  2146.335208: <stack trace>
 => trace_event_buffer_commit
 => trace_event_raw_event_sched_switch
 => __schedule
 => schedule
 => schedule_preempt_disabled
 => cpu_startup_entry
 => start_secondary

The stacktrace trigger isn't as bad, because it adds its own skip to the
stacktracing, but still has two events extra.

One issue is that if the stacktrace passes its own "regs" then there should
be no addition to the skip, as the regs will not include the functions being
called. This was an issue that was fixed by commit 7717c6be69 ("tracing:
Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()" as adding
the skip number for kprobes made the probes not have any stack at all.

But since this is only an issue when regs is being used, a skip should be
added if regs is NULL. Now we have:

 # echo 1 > options/stacktrace
 # echo 1 > events/sched/sched_switch/enable
 # cat trace
          <idle>-0     [000] d..2  1297.676333: <stack trace>
 => __schedule
 => schedule
 => schedule_preempt_disabled
 => cpu_startup_entry
 => rest_init
 => start_kernel
 => x86_64_start_reservations
 => x86_64_start_kernel

 # echo stacktrace > events/sched/sched_switch/trigger
 # cat trace
          <idle>-0     [002] d..3  1370.759745: <stack trace>
 => __schedule
 => schedule
 => schedule_preempt_disabled
 => cpu_startup_entry
 => start_secondary

And kprobes are not touched.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:35 -08:00
Jiri Olsa
4f0336a8a0 perf/ring_buffer: Prevent concurent ring buffer access
[ Upstream commit cd6fb677ce ]

Some of the scheduling tracepoints allow the perf_tp_event
code to write to ring buffer under different cpu than the
code is running on.

This results in corrupted ring buffer data demonstrated in
following perf commands:

  # perf record -e 'sched:sched_switch,sched:sched_wakeup' perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

       Total time: 0.383 [sec]
  [ perf record: Woken up 8 times to write data ]
  0x42b890 [0]: failed to process type: -1765585640
  [ perf record: Captured and wrote 4.825 MB perf.data (29669 samples) ]

  # perf report --stdio
  0x42b890 [0]: failed to process type: -1765585640

The reason for the corruption are some of the scheduling tracepoints,
that have __perf_task dfined and thus allow to store data to another
cpu ring buffer:

  sched_waking
  sched_wakeup
  sched_wakeup_new
  sched_stat_wait
  sched_stat_sleep
  sched_stat_iowait
  sched_stat_blocked

The perf_tp_event function first store samples for current cpu
related events defined for tracepoint:

    hlist_for_each_entry_rcu(event, head, hlist_entry)
      perf_swevent_event(event, count, &data, regs);

And then iterates events of the 'task' and store the sample
for any task's event that passes tracepoint checks:

  ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]);

  list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
    if (event->attr.type != PERF_TYPE_TRACEPOINT)
      continue;
    if (event->attr.config != entry->type)
      continue;

    perf_swevent_event(event, count, &data, regs);
  }

Above code can race with same code running on another cpu,
ending up with 2 cpus trying to store under the same ring
buffer, which is specifically not allowed.

This patch prevents the problem, by allowing only events with the same
current cpu to receive the event.

NOTE: this requires the use of (per-task-)per-cpu buffers for this
feature to work; perf-record does this.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
[peterz: small edits to Changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: e6dab5ffab ("perf/trace: Add ability to set a target task for events")
Link: http://lkml.kernel.org/r/20180923161343.GB15054@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:34 -08:00
Mark Brown
ebbfef1f74 Merge tag 'v4.4.161' into linux-linaro-lsk-v4.4
This is the 4.4.161 stable release
2018-10-15 10:19:18 +01:00
Prateek Sood
75fe5488b2 cgroup: Fix deadlock in cpu hotplug path
commit 116d2f7496 upstream.

Deadlock during cgroup migration from cpu hotplug path when a task T is
being moved from source to destination cgroup.

kworker/0:0
cpuset_hotplug_workfn()
   cpuset_hotplug_update_tasks()
      hotplug_update_tasks_legacy()
        remove_tasks_in_empty_cpuset()
          cgroup_transfer_tasks() // stuck in iterator loop
            cgroup_migrate()
              cgroup_migrate_add_task()

In cgroup_migrate_add_task() it checks for PF_EXITING flag of task T.
Task T will not migrate to destination cgroup. css_task_iter_start()
will keep pointing to task T in loop waiting for task T cg_list node
to be removed.

Task T
do_exit()
  exit_signals() // sets PF_EXITING
  exit_task_namespaces()
    switch_task_namespaces()
      free_nsproxy()
        put_mnt_ns()
          drop_collected_mounts()
            namespace_unlock()
              synchronize_rcu()
                _synchronize_rcu_expedited()
                  schedule_work() // on cpu0 low priority worker pool
                  wait_event() // waiting for work item to execute

Task T inserted a work item in the worklist of cpu0 low priority
worker pool. It is waiting for expedited grace period work item
to execute. This work item will only be executed once kworker/0:0
complete execution of cpuset_hotplug_workfn().

kworker/0:0 ==> Task T ==>kworker/0:0

In case of PF_EXITING task being migrated from source to destination
cgroup, migrate next available task in source cgroup.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
[AmitP: Upstream commit cherry-pick failed, so I picked the
        backported changes from CAF/msm-4.9 tree instead:
        https://source.codeaurora.org/quic/la/kernel/msm-4.9/commit/?id=49b74f1696417b270c89cd893ca9f37088928078]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-13 09:11:33 +02:00
Tao Huang
d376ad8f23 Merge branch 'linux-linaro-lsk-v4.4-android' of git://git.linaro.org/kernel/linux-linaro-stable.git
* linux-linaro-lsk-v4.4-android: (1212 commits)
  ANDROID: sdcardfs: Change current->fs under lock
  ANDROID: sdcardfs: Don't use OVERRIDE_CRED macro
  ANDROID: restrict store of prefer_idle as boolean
  BACKPORT: arm/syscalls: Optimize address limit check
  UPSTREAM: syscalls: Use CHECK_DATA_CORRUPTION for addr_limit_user_check
  BACKPORT: arm64/syscalls: Check address limit on user-mode return
  BACKPORT: x86/syscalls: Check address limit on user-mode return
  BACKPORT: lkdtm: add bad USER_DS test
  UPSTREAM: bug: switch data corruption check to __must_check
  BACKPORT: lkdtm: Add tests for struct list corruption
  UPSTREAM: bug: Provide toggle for BUG on data corruption
  UPSTREAM: list: Split list_del() debug checking into separate function
  UPSTREAM: rculist: Consolidate DEBUG_LIST for list_add_rcu()
  BACKPORT: list: Split list_add() debug checking into separate function
  FROMLIST: ANDROID: binder: Add BINDER_GET_NODE_INFO_FOR_REF ioctl.
  BACKPORT: arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW
  ANDROID: arm64: mm: fix 4.4.154 merge
  BACKPORT: zsmalloc: introduce zs_huge_class_size()
  BACKPORT: zram: drop max_zpage_size and use zs_huge_class_size()
  ANDROID: tracing: fix race condition reading saved tgids
  ...

Change-Id: I9f23db35eb926b6fa0d7af7dbbb55c9a37d536fc
2018-10-10 19:37:13 +08:00
Mark Brown
cf21042898 Merge tag 'v4.4.160' into linux-linaro-lsk-v4.4
This is the 4.4.160 stable release
2018-10-10 11:44:15 +01:00
Jessica Yu
10d721285d module: exclude SHN_UNDEF symbols from kallsyms api
[ Upstream commit 9f2d1e68cf ]

Livepatch modules are special in that we preserve their entire symbol
tables in order to be able to apply relocations after module load. The
unwanted side effect of this is that undefined (SHN_UNDEF) symbols of
livepatch modules are accessible via the kallsyms api and this can
confuse symbol resolution in livepatch (klp_find_object_symbol()) and
cause subtle bugs in livepatch.

Have the module kallsyms api skip over SHN_UNDEF symbols. These symbols
are usually not available for normal modules anyway as we cut down their
symbol tables to just the core (non-undefined) symbols, so this should
really just affect livepatch modules. Note that this patch doesn't
affect the display of undefined symbols in /proc/kallsyms.

Reported-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:07 +02:00
Thomas Gleixner
2e17841715 alarmtimer: Prevent overflow for relative nanosleep
[ Upstream commit 5f936e19cc ]

Air Icy reported:

  UBSAN: Undefined behaviour in kernel/time/alarmtimer.c:811:7
  signed integer overflow:
  1529859276030040771 + 9223372036854775807 cannot be represented in type 'long long int'
  Call Trace:
   alarm_timer_nsleep+0x44c/0x510 kernel/time/alarmtimer.c:811
   __do_sys_clock_nanosleep kernel/time/posix-timers.c:1235 [inline]
   __se_sys_clock_nanosleep kernel/time/posix-timers.c:1213 [inline]
   __x64_sys_clock_nanosleep+0x326/0x4e0 kernel/time/posix-timers.c:1213
   do_syscall_64+0xb8/0x3a0 arch/x86/entry/common.c:290

alarm_timer_nsleep() uses ktime_add() to add the current time and the
relative expiry value. ktime_add() has no sanity checks so the addition
can overflow when the relative timeout is large enough.

Use ktime_add_safe() which has the necessary sanity checks in place and
limits the result to the valid range.

Fixes: 9a7adcf5c6 ("timers: Posix interface for alarm-timers")
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1807020926360.1595@nanos.tec.linutronix.de
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:05 +02:00
Wei Wang
bec291181b ANDROID: restrict store of prefer_idle as boolean
It works as boolean so stores like a boolean too.

Bug: 116734731
Test: Set stune
Change-Id: I0daa3cc1723d009ed5bc2a71fa1c2e3d4ece6a7f
Signed-off-by: Wei Wang <wvw@google.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-10-04 14:20:38 +05:30
Adrian Salido
4c0933247e ANDROID: tracing: fix race condition reading saved tgids
Commit 939c7a4f04 ("tracing: Introduce saved_cmdlines_size file")
introduced ability to change saved cmdlines size. This resized saved
command lines but missed resizing tgid mapping as well.

Another issue is that when the resize happens, it removes saved command
lines and reallocates new memory for it. This introduced a race
condition when reading the global savecmd as this can be freed in the
middle of accessing it causing a use after free access. Fix this by
implementing locking.

Signed-off-by: Adrian Salido <salidoa@google.com>
Bug: 36007735
Change-Id: I334791ac35f8bcbd34362ed112aa624275a46947
(cherry picked from commit 7116d306da66de0de21e982024b4d3a3056f4461)
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-10-04 14:16:57 +05:30
Amit Pundir
c8f435d8fd Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
* linux-linaro-lsk-v4.4: (783 commits)
  Linux 4.4.159
  iw_cxgb4: only allow 1 flush on user qps
  HID: sony: Support DS4 dongle
  HID: sony: Update device ids
  arm64: Add trace_hardirqs_off annotation in ret_to_user
  ext4: don't mark mmp buffer head dirty
  ext4: fix online resizing for bigalloc file systems with a 1k block size
  ext4: fix online resize's handling of a too-small final block group
  ext4: recalucate superblock checksum after updating free blocks/inodes
  ext4: avoid divide by zero fault when deleting corrupted inline directories
  tty: vt_ioctl: fix potential Spectre v1
  drm/nouveau/drm/nouveau: Use pm_runtime_get_noresume() in connector_detect()
  ocfs2: fix ocfs2 read block panic
  scsi: target: iscsi: Use hex2bin instead of a re-implementation
  neighbour: confirm neigh entries when ARP packet is received
  net: hp100: fix always-true check for link up state
  net/appletalk: fix minor pointer leak to userspace in SIOCFINDIPDDPRT
  ipv6: fix possible use-after-free in ip6_xmit()
  gso_segment: Reset skb->mac_len after modifying network header
  mm: shmem.c: Correctly annotate new inodes for lockdep
  ...

Conflicts:
    Makefile
    fs/squashfs/block.c
    include/uapi/linux/prctl.h
    kernel/fork.c
    kernel/sys.c
        Trivial merge conflicts in above files. Resolved by rebasing
        corresponding AOSP changes.

    arch/arm64/mm/init.c
        Pick the changes from upstream version of AOSP patch
        "arm64: check for upper PAGE_SHIFT bits in pfn_valid" instead.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2018-10-03 15:00:28 +05:30
Mark Brown
c6ee9e74b2 Merge tag 'v4.4.159' into linux-linaro-lsk-v4.4
This is the 4.4.159 stable release

# gpg: Signature made Sat 29 Sep 2018 11:08:56 BST
# gpg:                using RSA key 647F28654894E3BD457199BE38DBBDC86092693E
# gpg: Good signature from "Greg Kroah-Hartman <gregkh@linuxfoundation.org>" [unknown]
# gpg:                 aka "Greg Kroah-Hartman (Linux kernel stable release signing key) <greg@kroah.com>" [unknown]
# gpg:                 aka "Greg Kroah-Hartman <gregkh@kernel.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 647F 2865 4894 E3BD 4571  99BE 38DB BDC8 6092 693E
2018-10-01 12:13:41 +01:00
Vaibhav Nagarnaik
fed4d566a8 ring-buffer: Allow for rescheduling when removing pages
commit 83f365554e upstream.

When reducing ring buffer size, pages are removed by scheduling a work
item on each CPU for the corresponding CPU ring buffer. After the pages
are removed from ring buffer linked list, the pages are free()d in a
tight loop. The loop does not give up CPU until all pages are removed.
In a worst case behavior, when lot of pages are to be freed, it can
cause system stall.

After the pages are removed from the list, the free() can happen while
the work is rescheduled. Call cond_resched() in the loop to prevent the
system hangup.

Link: http://lkml.kernel.org/r/20180907223129.71994-1-vnagarnaik@google.com

Cc: stable@vger.kernel.org
Fixes: 83f40318da ("ring-buffer: Make removal of ring buffer pages atomic")
Reported-by: Jason Behmer <jbehmer@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-29 03:08:52 -07:00
Biswajit Paul
88f6853de6 ANDROID: kernel: Restrict permissions of /proc/iomem.
The permissions of /proc/iomem currently are -r--r--r--. Everyone can
see its content. As iomem contains information about the physical memory
content of the device, restrict the information only to root.

Fix sts testPocCVE_2015_8944

Change-Id: If0be35c3fac5274151bea87b738a48e6ec0ae891
CRs-Fixed: 786116
Signed-off-by: Biswajit Paul <biswajitpaul@codeaurora.org>
Signed-off-by: Avijit Kanti Das <avijitnsec@codeaurora.org>
(cherry picked from https://android.googlesource.com/kernel/msm
 commit 60c6b65403b4c9567b53baadca0740915f698ca8)
2018-09-29 09:51:29 +08:00
Ronny Chevalier
20d6cff3fc audit: fix use-after-free in audit_add_watch
[ Upstream commit baa2a4fdd5 ]

audit_add_watch stores locally krule->watch without taking a reference
on watch. Then, it calls audit_add_to_parent, and uses the watch stored
locally.

Unfortunately, it is possible that audit_add_to_parent updates
krule->watch.
When it happens, it also drops a reference of watch which
could free the watch.

How to reproduce (with KASAN enabled):

    auditctl -w /etc/passwd -F success=0 -k test_passwd
    auditctl -w /etc/passwd -F success=1 -k test_passwd2

The second call to auditctl triggers the use-after-free, because
audit_to_parent updates krule->watch to use a previous existing watch
and drops the reference to the newly created watch.

To fix the issue, we grab a reference of watch and we release it at the
end of the function.

Signed-off-by: Ronny Chevalier <ronny.chevalier@hp.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:35:08 +02:00
Mark Brown
f4150b38ac Merge tag 'v4.4.157' into linux-linaro-lsk-v4.4
This is the 4.4.157 stable release
2018-09-20 08:35:34 -07:00
Prateek Sood
d914882c93 locking/osq_lock: Fix osq_lock queue corruption
commit 50972fe78f upstream.

Fix ordering of link creation between node->prev and prev->next in
osq_lock(). A case in which the status of optimistic spin queue is
CPU6->CPU2 in which CPU6 has acquired the lock.

        tail
          v
  ,-. <- ,-.
  |6|    |2|
  `-' -> `-'

At this point if CPU0 comes in to acquire osq_lock, it will update the
tail count.

  CPU2			CPU0
  ----------------------------------

				       tail
				         v
			  ,-. <- ,-.    ,-.
			  |6|    |2|    |0|
			  `-' -> `-'    `-'

After tail count update if CPU2 starts to unqueue itself from
optimistic spin queue, it will find an updated tail count with CPU0 and
update CPU2 node->next to NULL in osq_wait_next().

  unqueue-A

	       tail
	         v
  ,-. <- ,-.    ,-.
  |6|    |2|    |0|
  `-'    `-'    `-'

  unqueue-B

  ->tail != curr && !node->next

If reordering of following stores happen then prev->next where prev
being CPU2 would be updated to point to CPU0 node:

				       tail
				         v
			  ,-. <- ,-.    ,-.
			  |6|    |2|    |0|
			  `-'    `-' -> `-'

  osq_wait_next()
    node->next <- 0
    xchg(node->next, NULL)

	       tail
	         v
  ,-. <- ,-.    ,-.
  |6|    |2|    |0|
  `-'    `-'    `-'

  unqueue-C

At this point if next instruction
	WRITE_ONCE(next->prev, prev);
in CPU2 path is committed before the update of CPU0 node->prev = prev then
CPU0 node->prev will point to CPU6 node.

	       tail
    v----------. v
  ,-. <- ,-.    ,-.
  |6|    |2|    |0|
  `-'    `-'    `-'
     `----------^

At this point if CPU0 path's node->prev = prev is committed resulting
in change of CPU0 prev back to CPU2 node. CPU2 node->next is NULL
currently,

				       tail
			                 v
			  ,-. <- ,-. <- ,-.
			  |6|    |2|    |0|
			  `-'    `-'    `-'
			     `----------^

so if CPU0 gets into unqueue path of osq_lock it will keep spinning
in infinite loop as condition prev->next == node will never be true.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
[ Added pictures, rewrote comments. ]
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>
Cc: sramana@codeaurora.org
Link: http://lkml.kernel.org/r/1500040076-27626-1-git-send-email-prsood@codeaurora.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-19 22:48:56 +02:00
Prateek Sood
70cc08c44f locking/rwsem-xadd: Fix missed wakeup due to reordering of load
commit 9c29c31830 upstream.

If a spinner is present, there is a chance that the load of
rwsem_has_spinner() in rwsem_wake() can be reordered with
respect to decrement of rwsem count in __up_write() leading
to wakeup being missed:

 spinning writer                  up_write caller
 ---------------                  -----------------------
 [S] osq_unlock()                 [L] osq
  spin_lock(wait_lock)
  sem->count=0xFFFFFFFF00000001
            +0xFFFFFFFF00000000
  count=sem->count
  MB
                                   sem->count=0xFFFFFFFE00000001
                                             -0xFFFFFFFF00000001
                                   spin_trylock(wait_lock)
                                   return
 rwsem_try_write_lock(count)
 spin_unlock(wait_lock)
 schedule()

Reordering of atomic_long_sub_return_release() in __up_write()
and rwsem_has_spinner() in rwsem_wake() can cause missing of
wakeup in up_write() context. In spinning writer, sem->count
and local variable count is 0XFFFFFFFE00000001. It would result
in rwsem_try_write_lock() failing to acquire rwsem and spinning
writer going to sleep in rwsem_down_write_failed().

The smp_rmb() will make sure that the spinner state is
consulted after sem->count is updated in up_write context.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
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>
Cc: dave@stgolabs.net
Cc: longman@redhat.com
Cc: parri.andrea@gmail.com
Cc: sramana@codeaurora.org
Link: http://lkml.kernel.org/r/1504794658-15397-1-git-send-email-prsood@codeaurora.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-19 22:48:56 +02:00
Vegard Nossum
798ef283a8 kthread: Fix use-after-free if kthread fork fails
commit 4d6501dce0 upstream.

If a kthread forks (e.g. usermodehelper since commit 1da5c46fa9) but
fails in copy_process() between calling dup_task_struct() and setting
p->set_child_tid, then the value of p->set_child_tid will be inherited
from the parent and get prematurely freed by free_kthread_struct().

    kthread()
     - worker_thread()
        - process_one_work()
        |  - call_usermodehelper_exec_work()
        |     - kernel_thread()
        |        - _do_fork()
        |           - copy_process()
        |              - dup_task_struct()
        |                 - arch_dup_task_struct()
        |                    - tsk->set_child_tid = current->set_child_tid // implied
        |              - ...
        |              - goto bad_fork_*
        |              - ...
        |              - free_task(tsk)
        |                 - free_kthread_struct(tsk)
        |                    - kfree(tsk->set_child_tid)
        - ...
        - schedule()
           - __schedule()
              - wq_worker_sleeping()
                 - kthread_data(task)->flags // UAF

The problem started showing up with commit 1da5c46fa9 since it reused
->set_child_tid for the kthread worker data.

A better long-term solution might be to get rid of the ->set_child_tid
abuse. The comment in set_kthread_struct() also looks slightly wrong.

Debugged-by: Jamie Iles <jamie.iles@oracle.com>
Fixes: 1da5c46fa9 ("kthread: Make struct kthread kmalloc'ed")
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jamie Iles <jamie.iles@oracle.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170509073959.17858-1-vegard.nossum@oracle.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-19 22:48:55 +02:00
Sudeep Holla
27e83f7dd9 genirq: Delay incrementing interrupt count if it's disabled/pending
commit a946e8c717 upstream.

In case of a wakeup interrupt, irq_pm_check_wakeup disables the interrupt
and marks it pending and suspended, disables it and notifies the pm core
about the wake event. The interrupt gets handled later once the system
is resumed.

However the irq stats is updated twice: once when it's disabled waiting
for the system to resume and later when it's handled, resulting in wrong
counting of the wakeup interrupt when waking up the system.

This patch updates the interrupt count so that it's updated only when
the interrupt gets handled. It's already handled correctly in
handle_edge_irq and handle_edge_eoi_irq.

Reported-by: Manoil Claudiu <claudiu.manoil@freescale.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1446661957-1019-1-git-send-email-sudeep.holla@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:40:40 +02:00
Jann Horn
b7befd11e0 fork: don't copy inconsistent signal handler state to child
[ Upstream commit 06e62a46bb ]

Before this change, if a multithreaded process forks while one of its
threads is changing a signal handler using sigaction(), the memcpy() in
copy_sighand() can race with the struct assignment in do_sigaction().  It
isn't clear whether this can cause corruption of the userspace signal
handler pointer, but it definitely can cause inconsistency between
different fields of struct sigaction.

Take the appropriate spinlock to avoid this.

I have tested that this patch prevents inconsistency between sa_sigaction
and sa_flags, which is possible before this patch.

Link: http://lkml.kernel.org/r/20180702145108.73189-1-jannh@google.com
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:40:38 +02:00
Mark Brown
ff05cdd619 Merge tag 'v4.4.155' into linux-linaro-lsk-v4.4
This is the 4.4.155 stable release
2018-09-10 10:16:13 +01:00
Jann Horn
3d4c43c8f0 userns: move user access out of the mutex
commit 5820f140ed upstream.

The old code would hold the userns_state_mutex indefinitely if
memdup_user_nul stalled due to e.g. a userfault region. Prevent that by
moving the memdup_user_nul in front of the mutex_lock().

Note: This changes the error precedence of invalid buf/count/*ppos vs
map already written / capabilities missing.

Fixes: 22d917d80e ("userns: Rework the user_namespace adding uid/gid...")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Christian Brauner <christian@brauner.io>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09 20:04:35 +02:00