It turns out that people do actually depend on the shebang string being
truncated, and on the fact that an interpreter (like perl) will often
just re-interpret it entirely to get the full argument list.
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&idev->info_lock);
lock(&mm->mmap_sem);
lock(&idev->info_lock);
lock(&mm->mmap_sem);
*** DEADLOCK ***
1 lock held by XXX/1910:
#0: (&idev->info_lock){+.+...}, at: [<ffffffffc0638a06>] uio_write+0x46/0x130 [uio]
uio_mmap has multiple fail paths to set return value to nonzero then
goto out. However, it always returns *0* from the *out* at end, and
this will mislead callers who check the return value of this function.
Fixes: 57c5f4df0a5a0ee ("uio: fix crash after the device is unregistered") CC: Xiubo Li <xiubli@redhat.com> Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn> Cc: stable <stable@vger.kernel.org> Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uio: Prevent device destruction while fds are open
The problem is the addition of spin_lock_irqsave in uio_write. This
leads to hitting uio_write -> copy_from_user -> _copy_from_user ->
might_fault and the logs filling up with sleeping warnings.
I also noticed some uio drivers allocate memory, sleep, grab mutexes
from callouts like open() and release and uio is now doing
spin_lock_irqsave while calling them.
Reported-by: Mike Christie <mchristi@redhat.com> CC: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Signed-off-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prevent destruction of a uio_device while user space apps hold open
file descriptors to that device. Further, access to the 'info' member
of the struct uio_device is protected by spinlock. This is to ensure
stale pointers to data not under control of the UIO subsystem are not
dereferenced.
Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[4.14 change __poll_t to unsigned int] Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The perf_event_attr::task is 1 by default for first (tracking) event in
the session. Setting task=1 as default and adding task=0 for cases that
need it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20170703145030.12903-16-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "Rantala, Tommi T. (Nokia - FI/Espoo)" <tommi.t.rantala@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The caller of ndo_start_xmit may not already have called
skb_reset_mac_header. The returned value of skb_mac_header/eth_hdr
therefore can be in the wrong position and even outside the current skbuff.
This for example happens when the user binds to the device using a
PF_PACKET-SOCK_RAW with enabled qdisc-bypass:
int opt = 4;
setsockopt(sock, SOL_PACKET, PACKET_QDISC_BYPASS, &opt, sizeof(opt));
Since eth_hdr is used all over the codebase, the batadv_interface_tx
function must always take care of resetting it.
It is not allowed to use WARN* helpers on potential incorrect input from
the user or transient problems because systems configured as panic_on_warn
will reboot due to such a problem.
A NULL return value of __dev_get_by_index can be caused by various problems
which can either be related to the system configuration or problems
(incorrectly returned network namespaces) in other (virtual) net_device
drivers. batman-adv should not cause a (harmful) WARN in this situation and
instead only report it via a simple message.
Fixes: b7eddd0b3950 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface") Reported-by: syzbot+c764de0fcfadca9a8595@syzkaller.appspotmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The check assumes that in transport mode, the first templates family
must match the address family of the policy selector.
Syzkaller managed to build a template using MODE_ROUTEOPTIMIZATION,
with ipv4-in-ipv6 chain, leading to following splat:
BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x1db/0x1854
Read of size 4 at addr ffff888063e57aa0 by task a.out/2050
xfrm_state_find+0x1db/0x1854
xfrm_tmpl_resolve+0x100/0x1d0
xfrm_resolve_and_create_bundle+0x108/0x1000 [..]
Problem is that addresses point into flowi4 struct, but xfrm_state_find
treats them as being ipv6 because it uses templ->encap_family is used
(AF_INET6 in case of reproducer) rather than family (AF_INET).
This patch inverts the logic: Enforce 'template family must match
selector' EXCEPT for tunnel and BEET mode.
In BEET and Tunnel mode, xfrm_tmpl_resolve_one will have remote/local
address pointers changed to point at the addresses found in the template,
rather than the flowi ones, so no oob read will occur.
con_fault() can transition the connection into STANDBY right after
ceph_con_keepalive() clears STANDBY in clear_standby():
libceph user thread ceph-msgr worker
ceph_con_keepalive()
mutex_lock(&con->mutex)
clear_standby(con)
mutex_unlock(&con->mutex)
mutex_lock(&con->mutex)
con_fault()
...
if KEEPALIVE_PENDING isn't set
set state to STANDBY
...
mutex_unlock(&con->mutex)
set KEEPALIVE_PENDING
set WRITE_PENDING
This triggers warnings in clear_standby() when either ceph_con_send()
or ceph_con_keepalive() get to clearing STANDBY next time.
I don't see a reason to condition queue_con() call on the previous
value of KEEPALIVE_PENDING, so move the setting of KEEPALIVE_PENDING
into the critical section -- unlike WRITE_PENDING, KEEPALIVE_PENDING
could have been a non-atomic flag.
As Jan Kara pointed out, this change was unsafe since it means we lose
the call to sync_mapping_buffers() in the nojournal case. The
original point of the commit was avoid taking the inode mutex (since
it causes a lockdep warning in generic/113); but we need the mutex in
order to call sync_mapping_buffers().
The proposed patch was to fix a syzbot complaint, but the problem can
also demonstrated via "kvm-xfstests -c nojournal generic/113".
Multiple solutions were discused in the e-mail thread, but none have
landed in the kernel as of this writing. Anyway, commit ad211f3e94b314 is absolutely the wrong way to suppress the lockdep, so
revert it.
Fixes: ad211f3e94b314a910d4af03178a0b52a7d1ee0a ("ext4: use ext4_write_inode() when fsyncing w/o a journal") Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ring buffer implementation in hid_debug_event() and hid_debug_events_read()
is strange allowing lost or corrupted data. After commit 717adfdaf147
("HID: debug: check length before copy_to_user()") it is possible to enter
an infinite loop in hid_debug_events_read() by providing 0 as count, this
locks up a system. Fix this by rewriting the ring buffer implementation
with kfifo and simplify the code.
This fixes CVE-2019-3819.
v2: fix an execution logic and add a comment
v3: use __set_current_state() instead of set_current_state()
Backport to v4.14: 2 tree-wide patches 6396bb22151 ("treewide: kzalloc() ->
kcalloc()") and a9a08845e9ac ("vfs: do bulk POLL* -> EPOLL* replacement")
are missing in v4.14 so cherry-pick relevant pieces.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1669187 Cc: stable@vger.kernel.org # v4.18+ Fixes: cd667ce24796 ("HID: use debugfs for events/reports dumping") Fixes: 717adfdaf147 ("HID: debug: check length before copy_to_user()") Signed-off-by: Vladis Dronov <vdronov@redhat.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function was unconditionally returning 0, and a caller would have to
rely on the returned fence pointer being NULL to detect errors. However,
the function vmw_execbuf_copy_fence_user() would expect a non-zero error
code in that case and would BUG otherwise.
So make sure we return a proper non-zero error code if the fence pointer
returned is NULL.
Some drivers use IEEE80211_KEY_FLAG_SW_MGMT_TX to indicate that management
frames need to be software encrypted. Since normal data packets are still
encrypted by the hardware, crypto_tx_tailroom_needed_cnt gets decremented
after key upload to hw. This can lead to passing skbs to ccmp_encrypt_skb,
which don't have the necessary tailroom for software encryption.
Change the code to add tailroom for encrypted management packets, even if
crypto_tx_tailroom_needed_cnt is 0.
Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When generating vdso-o32.lds & vdso-n32.lds for use with programs
running as compat ABIs under 64b kernels, we previously haven't included
the compiler flags that are supposedly common to all ABIs - ie. those in
the ccflags-vdso variable.
This is problematic in cases where we need to provide the -m%-float flag
in order to ensure that we don't attempt to use a floating point ABI
that's incompatible with the target CPU & ABI. For example a toolchain
using current gcc trunk configured --with-fp-32=xx fails to build a
64r6el_defconfig kernel with the following error:
Include $(ccflags-vdso) for the compat VDSO .lds builds, just as it is
included for the native VDSO .lds & when compiling objects for the
compat VDSOs. This ensures we consistently provide the -msoft-float flag
amongst others, avoiding the problem by ensuring we're agnostic to the
toolchain defaults.
Signed-off-by: Paul Burton <paul.burton@mips.com> Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO") Cc: linux-mips@vger.kernel.org Cc: Kevin Hilman <khilman@baylibre.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Maciej W . Rozycki <macro@linux-mips.org> Cc: stable@vger.kernel.org # v4.4+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Accordingly to the documentation
---cut---
The GCR_ERROR_CAUSE.ERR_TYPE field and the GCR_ERROR_MULT.ERR_TYPE
fields can be cleared by either a reset or by writing the current
value of GCR_ERROR_CAUSE.ERR_TYPE to the
GCR_ERROR_CAUSE.ERR_TYPE register.
---cut---
Do exactly this. Original value of cm_error may be safely written back;
it clears error cause and keeps other bits untouched.
Fixes: 3885c2b463f6 ("MIPS: CM: Add support for reporting CM cache errors") Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@linux.intel.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # v4.3+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
debugfs_rename() needs to check that the dentries passed into it really
are valid, as sometimes they are not (i.e. if the return value of
another debugfs call is passed into this one.) So fix this up by
properly checking if the two parent directories are errors (they are
allowed to be NULL), and if the dentry to rename is not NULL or an
error.
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop failing
to deliver SIGHUP but always trying.
When the stack overflows delivery of SIGHUP fails and force_sigsegv is
called. Unfortunately because SIGSEGV is numerically higher than
SIGHUP next_signal tries again to deliver a SIGHUP.
From a quality of implementation standpoint attempting to deliver the
timer SIGHUP signal is wrong. We should attempt to deliver the
synchronous SIGSEGV signal we just forced.
We can make that happening in a fairly straight forward manner by
instead of just looking at the signal number we also look at the
si_code. In particular for exceptions (aka synchronous signals) the
si_code is always greater than 0.
That still has the potential to pick up a number of asynchronous
signals as in a few cases the same si_codes that are used
for synchronous signals are also used for asynchronous signals,
and SI_KERNEL is also included in the list of possible si_codes.
Still the heuristic is much better and timer signals are definitely
excluded. Which is enough to prevent all known ways for someone
sending a process signals fast enough to cause unexpected and
arguably incorrect behavior.
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop
failing to deliver SIGHUP but always trying.
Upon examination it turns out part of the problem is actually most of
the solution. Since 2.5 signal delivery has found all fatal signals,
marked the signal group for death, and queued SIGKILL in every threads
thread queue relying on signal->group_exit_code to preserve the
information of which was the actual fatal signal.
The conversion of all fatal signals to SIGKILL results in the
synchronous signal heuristic in next_signal kicking in and preferring
SIGHUP to SIGKILL. Which is especially problematic as all
fatal signals have already been transformed into SIGKILL.
Instead of dequeueing signals and depending upon SIGKILL to
be the first signal dequeued, first test if the signal group
has already been marked for death. This guarantees that
nothing in the signal queue can prevent a process that needs
to exit from exiting.
Prior to this commit there were 3 issues with our handling of the TS-pin:
1) There are 2 ways how the firmware can disable monitoring of the TS-pin
for designs which do not have a temperature-sensor for the battery:
a) Clearing bit 0 of the AXP20X_ADC_EN1 register
b) Setting bit 2 of the AXP288_ADC_TS_PIN_CTRL monitoring
Prior to this commit we were unconditionally setting both bits to the
value used on devices with a TS. This causes the temperature protection to
kick in on devices without a TS, such as the Jumper ezbook v2, causing
them to not charge under Linux.
This commit fixes this by using regmap_update_bits when updating these 2
registers, leaving the 2 mentioned bits alone.
The next 2 problems are related to our handling of the current-source
for the TS-pin. The current-source used for the battery temp-sensor (TS)
is shared with the GPADC. For proper fuel-gauge and charger operation the
TS current-source needs to be permanently on. But to read the GPADC we
need to temporary switch the TS current-source to ondemand, so that the
GPADC can use it, otherwise we will always read an all 0 value.
2) Problem 2 is we were writing hardcoded values to the ADC TS pin-ctrl
register, overwriting various other unrelated bits. Specifically we were
overwriting the current-source setting for the TS and GPIO0 pins, forcing
it to 80ųA independent of its original setting. On a Chuwi Vi10 tablet
this was causing us to get a too high adc value (due to a too high
current-source) resulting in the following errors being logged:
ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion]
ACPI Error: Method parse/execution failed \_SB.SXP1._TMP, AE_ERROR
This commit fixes this by using regmap_update_bits to change only the
relevant bits.
3) After reading the GPADC channel we were unconditionally enabling the
TS current-source even on devices where the TS-pin is not used and the
current-source thus was off before axp288_adc_read_raw call.
This commit fixes this by making axp288_adc_set_ts a nop on devices where
the ADC is not enabled for the TS-pin.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1610545 Fixes: 3091141d7803 ("iio: adc: axp288: Fix the GPADC pin ...") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Disable BCH soft reset according to MX23 erratum #2847 ("BCH soft
reset may cause bus master lock up") for MX28 too. It has the same
problem.
Observed problem: once per 100,000+ MX28 reboots NAND read failed on
DMA timeout errors:
[ 1.770823] UBI: attaching mtd3 to ubi0
[ 2.768088] gpmi_nand: DMA timeout, last DMA :1
[ 3.958087] gpmi_nand: BCH timeout, last DMA :1
[ 4.156033] gpmi_nand: Error in ECC-based read: -110
[ 4.161136] UBI warning: ubi_io_read: error -110 while reading 64
bytes from PEB 0:0, read only 0 bytes, retry
[ 4.171283] step 1 error
[ 4.173846] gpmi_nand: Chip: 0, Error -1
Without BCH soft reset we successfully executed 1,000,000 MX28 reboots.
I have a quote from NXP regarding this problem, from July 18th 2016:
"As the i.MX23 and i.MX28 are of the same generation, they share many
characteristics. Unfortunately, also the erratas may be shared.
In case of the documented erratas and the workarounds, you can also
apply the workaround solution of one device on the other one. This have
been reported, but I’m afraid that there are not an estimated date for
updating the Errata documents.
Please accept our apologies for any inconveniences this may cause."
intel_pmu_cpu_prepare() allocated memory for ->shared_regs among other
members of struct cpu_hw_events. This memory is released in
intel_pmu_cpu_dying() which is wrong. The counterpart of the
intel_pmu_cpu_prepare() callback is x86_pmu_dead_cpu().
Otherwise if the CPU fails on the UP path between CPUHP_PERF_X86_PREPARE
and CPUHP_AP_PERF_X86_STARTING then it won't release the memory but
allocate new memory on the next attempt to online the CPU (leaking the
old memory).
Also, if the CPU down path fails between CPUHP_AP_PERF_X86_STARTING and
CPUHP_PERF_X86_PREPARE then the CPU will go back online but never
allocate the memory that was released in x86_pmu_dying_cpu().
Make the memory allocation/free symmetrical in regard to the CPU hotplug
notifier by moving the deallocation to intel_pmu_cpu_dead().
This started in commit:
a7e3ed1e47011 ("perf: Add support for supplementary event registers").
In principle the bug was introduced in v2.6.39 (!), but it will almost
certainly not backport cleanly across the big CPU hotplug rewrite between v4.7-v4.15...
Reported-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With developer hat on Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With maintainer hat on Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> 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: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: bp@alien8.de Cc: hpa@zytor.com Cc: jolsa@kernel.org Cc: kan.liang@linux.intel.com Cc: namhyung@kernel.org Cc: <stable@vger.kernel.org> Fixes: a7e3ed1e47011 ("perf: Add support for supplementary event registers"). Link: https://lkml.kernel.org/r/20181219165350.6s3jvyxbibpvlhtq@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ He Zhe: Fixes conflict caused by missing disable_counter_freeze which is
introduced since v4.20 af3bdb991a5cb. ] Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix potential memory corruption and panic in loopback for IB_WR_SEND
variants.
The code blindly assumes the posted length will fit in the fetched rwqe,
which is not a valid assumption.
Fix by adding a limit test, and triggering the appropriate send completion
and putting the QP in an error state. This mimics the handling for
non-loopback QPs.
Fixes: 15703461533a ("IB/{hfi1, qib, rdmavt}: Move ruc_loopback to rdmavt") Cc: <stable@vger.kernel.org> #v4.20+ Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
The spec allows us to return NFS4ERR_SEQ_FALSE_RETRY if we notice that
the client is making a call that matches a previous (slot, seqid) pair
but that *isn't* actually a replay, because some detail of the call
doesn't actually match the previous one.
Catching every such case is difficult, but we may as well catch a few
easy ones. This also handles the case described in the previous patch,
in a different way.
The spec does however require us to catch the case where the difference
is in the rpc credentials. This prevents somebody from snooping another
user's replies by fabricating retries.
(But the practical value of the attack is limited by the fact that the
replies with the most sensitive data are READ replies, which are not
normally cached.)
Tested-by: Olga Kornievskaia <aglo@umich.edu> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Donald Buczek <buczek@molgen.mpg.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently our handling of 4.1+ requests without "cachethis" set is
confusing and not quite correct.
Suppose a client sends a compound consisting of only a single SEQUENCE
op, and it matches the seqid in a session slot (so it's a retry), but
the previous request with that seqid did not have "cachethis" set.
The obvious thing to do might be to return NFS4ERR_RETRY_UNCACHED_REP,
but the protocol only allows that to be returned on the op following the
SEQUENCE, and there is no such op in this case.
The protocol permits us to cache replies even if the client didn't ask
us to. And it's easy to do so in the case of solo SEQUENCE compounds.
So, when we get a solo SEQUENCE, we can either return the previously
cached reply or NFSERR_SEQ_FALSE_RETRY if we notice it differs in some
way from the original call.
Currently, we're returning a corrupt reply in the case a solo SEQUENCE
matches a previous compound with more ops. This actually matters
because the Linux client recently started doing this as a way to recover
from lost replies to idempotent operations in the case the process doing
the original reply was killed: in that case it's difficult to keep the
original arguments around to do a real retry, and the client no longer
cares what the result is anyway, but it would like to make sure that the
slot's sequence id has been incremented, and the solo SEQUENCE assures
that: if the server never got the original reply, it will increment the
sequence id. If it did get the original reply, it won't increment, and
nothing else that about the reply really matters much. But we can at
least attempt to return valid xdr!
Tested-by: Olga Kornievskaia <aglo@umich.edu> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Donald Buczek <buczek@molgen.mpg.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There still is a race window after the commit b027e2298bd588
("tty: fix data race between tty_init_dev and flush of buf"),
and we encountered this crash issue if receive_buf call comes
before tty initialization completes in tty_open and
tty->driver_data may be NULL.
it can be fixed by extending ldisc semaphore lock in tty_init_dev
to driver_data initialized completely after tty->ops->open(), but
this will lead to get lock on one function and unlock in some other
function, and hard to maintain, so fix this race only by checking
tty->driver_data when receiving, and return if tty->driver_data
is NULL, and n_tty_receive_buf_common maybe calls uart_unthrottle,
so add the same check.
Because the tty layer knows nothing about the driver associated with the
device, the tty layer can not do anything here, it is up to the tty
driver itself to check for this type of race. Fix up the serial driver
to correctly check to see if it is finished binding with the device when
being called, and if not, abort the tty calls.
[Description and problem report and testing from Li RongQing, I rewrote
the patch to be in the serial layer, not in the tty core - gregkh]
Reported-by: Li RongQing <lirongqing@baidu.com> Tested-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Wang Li <wangli39@baidu.com> Signed-off-by: Zhang Yu <zhangyu31@baidu.com> Signed-off-by: Li RongQing <lirongqing@baidu.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Notice that the use of the bitwise OR operator '|' always leads to true
in this particular case, which seems a bit suspicious due to the context
in which this expression is being used.
Fix this by using bitwise AND operator '&' instead.
This bug was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields") Link: http://lkml.kernel.org/r/20190122233439.GA5868@embeddedor Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The perf tool uses /proc/sys/kernel/perf_event_mlock_kb to determine how
large its ringbuffer mmap should be. This can be configured to arbitrary
values, which can be larger than the maximum possible allocation from
kmalloc.
When this is configured to a suitably large value (e.g. thanks to the
perf fuzzer), attempting to use perf record triggers a WARN_ON_ONCE() in
__alloc_pages_nodemask():
WARNING: CPU: 2 PID: 5666 at mm/page_alloc.c:4511 __alloc_pages_nodemask+0x3f8/0xbc8
Let's avoid this by checking that the requested allocation is possible
before calling kzalloc.
Reported-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> 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: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20190110142745.25495-1-mark.rutland@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Internal injection testing crashed with a console log that said:
mce: [Hardware Error]: CPU 7: Machine Check Exception: f Bank 0: bd80000000100134
This caused a lot of head scratching because the MCACOD (bits 15:0) of
that status is a signature from an L1 data cache error. But Linux says
that it found it in "Bank 0", which on this model CPU only reports L1
instruction cache errors.
The answer was that Linux doesn't initialize "m->bank" in the case that
it finds a fatal error in the mce_no_way_out() pre-scan of banks. If
this was a local machine check, then this partially initialized struct
mce is being passed to mce_panic().
Fix is simple: just initialize m->bank in the case of a fatal error.
Fixes: 40c36e2741d7 ("x86/mce: Fix incorrect "Machine check from unknown source" message") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Cc: stable@vger.kernel.org # v4.18 Note pre-v5.0 arch/x86/kernel/cpu/mce/core.c was called arch/x86/kernel/cpu/mcheck/mce.c Link: https://lkml.kernel.org/r/20190201003341.10638-1-tony.luck@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some PCI uncore PMUs cannot be registered on an 8-socket system (HPE
Superdome Flex).
To understand which Socket the PCI uncore PMUs belongs to, perf retrieves
the local Node ID of the uncore device from CPUNODEID(0xC0) of the PCI
configuration space, and the mapping between Socket ID and Node ID from
GIDNIDMAP(0xD4). The Socket ID can be calculated accordingly.
The local Node ID is only available at bit 2:0, but current code doesn't
mask it. If a BIOS doesn't clear the rest of the bits, an incorrect Node ID
will be fetched.
Filter the Node ID by adding a mask.
Reported-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> 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: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> # v3.7+ Fixes: 7c94ee2e0917 ("perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support") Link: https://lkml.kernel.org/r/1548600794-33162-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
73d5e2b47264 ("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:
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: 73d5e2b47264 ("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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple code paths where an hrtimer may have been started to
emulate an L1 VMX preemption timer that can result in a call to free_nested
without an intervening L2 exit where the hrtimer is normally
cancelled. Unconditionally cancel in free_nested to cover all cases.
Embargoed until Feb 7th 2019.
Signed-off-by: Peter Shier <pshier@google.com> Reported-by: Jim Mattson <jmattson@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reported-by: Felix Wilhelm <fwilhelm@google.com> Cc: stable@kernel.org
Message-Id: <20181011184646.154065-1-pshier@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. creates a device that holds a reference to the VM object (with a borrowed
reference, the VM's refcount has not been bumped yet)
2. initializes the device
3. transfers the reference to the device to the caller's file descriptor table
4. calls kvm_get_kvm() to turn the borrowed reference to the VM into a real
reference
The ownership transfer in step 3 must not happen before the reference to the VM
becomes a proper, non-borrowed reference, which only happens in step 4.
After step 3, an attacker can close the file descriptor and drop the borrowed
reference, which can cause the refcount of the kvm object to drop to zero.
This means that we need to grab a reference for the device before
anon_inode_getfd(), otherwise the VM can disappear from under us.
Emulation of certain instructions (VMXON, VMCLEAR, VMPTRLD, VMWRITE with
memory operand, INVEPT, INVVPID) can incorrectly inject a page fault
when passed an operand that points to an MMIO address. The page fault
will use uninitialized kernel stack memory as the CR2 and error code.
The right behavior would be to abort the VM with a KVM_EXIT_INTERNAL_ERROR
exit to userspace; however, it is not an easy fix, so for now just
ensure that the error code and CR2 are zero.
Embargoed until Feb 7th 2019.
Reported-by: Felix Wilhelm <fwilhelm@google.com> Cc: stable@kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because the PCI code had recently added a file named 'revision' to every
PCI device. Fix this by renaming the aic94xx revision file to
aic_revision. This is safe to do for us because as far as I can tell,
there's nothing in userspace relying on the current aic94xx revision file
so it can be renamed without breaking anything.
Fixes: 702ed3be1b1b (PCI: Create revision file in sysfs) Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Presently when an error is encountered during probe of the cxlflash
adapter, a deadlock is seen with cpu thread stuck inside
cxlflash_remove(). Below is the trace of the deadlock as logged by
khungtaskd:
cxlflash 0006:00:00.0: cxlflash_probe: init_afu failed rc=-16
INFO: task kworker/80:1:890 blocked for more than 120 seconds.
Not tainted 5.0.0-rc4-capi2-kexec+ #2
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/80:1 D 0 890 2 0x00000808
Workqueue: events work_for_cpu_fn
Call Trace:
0x4d72136320 (unreliable)
__switch_to+0x2cc/0x460
__schedule+0x2bc/0xac0
schedule+0x40/0xb0
cxlflash_remove+0xec/0x640 [cxlflash]
cxlflash_probe+0x370/0x8f0 [cxlflash]
local_pci_probe+0x6c/0x140
work_for_cpu_fn+0x38/0x60
process_one_work+0x260/0x530
worker_thread+0x280/0x5d0
kthread+0x1a8/0x1b0
ret_from_kernel_thread+0x5c/0x80
INFO: task systemd-udevd:5160 blocked for more than 120 seconds.
The deadlock occurs as cxlflash_remove() is called from cxlflash_probe()
without setting 'cxlflash_cfg->state' to STATE_PROBED and the probe thread
starts to wait on 'cxlflash_cfg->reset_waitq'. Since the device was never
successfully probed the 'cxlflash_cfg->state' never changes from
STATE_PROBING hence the deadlock occurs.
We fix this deadlock by setting the variable 'cxlflash_cfg->state' to
STATE_PROBED in case an error occurs during cxlflash_probe() and just
before calling cxlflash_remove().
Cc: stable@vger.kernel.org Fixes: c21e0bbfc485("cxlflash: Base support for IBM CXL Flash Adapter") Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The send_xchar() and tiocmset() tty operations are optional. Add the
missing sanity checks to prevent user-space triggerable NULL-pointer
dereferences.
Fixes: 6b9ad1c742bf ("staging: speakup: add send_xchar, tiocmset and input functionality for tty") Cc: stable <stable@vger.kernel.org> # 4.13 Cc: Okash Khawaja <okash.khawaja@gmail.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Handling short packets (length < max packet size) in the Inventra DMA
engine in the MUSB driver causes the MUSB DMA controller to hang. An
example of a problem that is caused by this problem is when streaming
video out of a UVC gadget, only the first video frame is transferred.
For short packets (mode-0 or mode-1 DMA), MUSB_TXCSR_TXPKTRDY must be
set manually by the driver. This was previously done in musb_g_tx
(musb_gadget.c), but incorrectly (all csr flags were cleared, and only
MUSB_TXCSR_MODE and MUSB_TXCSR_TXPKTRDY were set). Fixing that problem
allows some requests to be transferred correctly, but multiple requests
were often put together in one USB packet, and caused problems if the
packet size was not a multiple of 4. Instead, set MUSB_TXCSR_TXPKTRDY
in dma_controller_irq (musbhsdma.c), just like host mode transfers.
This topic was originally tackled by Nicolas Boichat [0] [1] and is
discussed further at [2] as part of his GSoC project [3].
power off the phy should be done before populate the phy. Otherwise,
am335x_init() could be called by the phy owner to power on the phy first,
then am335x_phy_probe() turns off the phy again without the caller knowing
it.
Fixes: 2fc711d76352 ("usb: phy: am335x: Enable USB remote wakeup using PHY wakeup") Cc: stable@vger.kernel.org # v3.18+ Signed-off-by: Bin Liu <b-liu@ti.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On systems or VMs where multiple devices share a single DevID
(because they sit behind a PCI bridge, or because the HW is
broken in funky ways), we reuse the save its_device structure
in order to reflect this.
It turns out that there is a distinct lack of locking when looking
up the its_device, and two device being probed concurrently can result
in double allocations. That's obviously not nice.
A solution for this is to have a per-ITS mutex that serializes device
allocation.
A similar issue exists on the freeing side, which can run concurrently
with the allocation. On top of now taking the appropriate lock, we
also make sure that a shared device is never freed, as we have no way
to currently track the life cycle of such object.
commit 56222b212e8e ("futex: Drop hb->lock before enqueueing on the
rtmutex") changed the locking rules in the futex code so that the hash
bucket lock is not longer held while the waiter is enqueued into the
rtmutex wait list. This made the lock and the unlock path symmetric, but
unfortunately the possible early exit from __rt_mutex_proxy_start() due to
a detected deadlock was not updated accordingly. That allows a concurrent
unlocker to observe inconsitent state which triggers the warning in the
unlock path.
The problem is caused by the remove(rtmutex_waiter) in the failure case of
__rt_mutex_proxy_start() as this lets the unlocker observe a waiter in the
hash bucket but no waiter on the rtmutex, i.e. inconsistent state.
The original commit handles this correctly for the other early return cases
(timeout, signal) by delaying the removal of the rtmutex waiter until the
returning task reacquired the hash bucket lock.
Treat the failure case of __rt_mutex_proxy_start() in the same way and let
the existing cleanup code handle the eventual handover of the rtmutex
gracefully. The regular rt_mutex_proxy_start() gains the rtmutex waiter
removal for the failure case, so that the other callsites are still
operating correctly.
Add proper comments to the code so all these details are fully documented.
Thanks to Peter for helping with the analysis and writing the really
valuable code comments.
Fixes: 56222b212e8e ("futex: Drop hb->lock before enqueueing on the rtmutex") Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Co-developed-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: Stefan Liebler <stli@linux.ibm.com> Cc: Sebastian Sewior <bigeasy@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1901292311410.1950@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Once the "ld_queue" list is not empty, next descriptor will migrate
into "ld_active" list. The "desc" variable will be overwritten
during that transition. And later the dmaengine_desc_get_callback_invoke()
will use it as an argument. As result we invoke wrong callback.
That behaviour was in place since:
commit fcaaba6c7136 ("dmaengine: imx-dma: fix callback path in tasklet").
But after commit 4cd13c21b207 ("softirq: Let ksoftirqd do its job")
things got worse, since possible delay between tasklet_schedule()
from DMA irq handler and actual tasklet function execution got bigger.
And that gave more time for new DMA request to be submitted and
to be put into "ld_queue" list.
It has been noticed that DMA issue is causing problems for "mxc-mmc"
driver. While stressing the system with heavy network traffic and
writing/reading to/from sd card simultaneously the timeout may happen:
10013000.sdhci: mxcmci_watchdog: read time out (status = 0x30004900)
There are multiple issues with bcm2835_dma_abort() (which is called on
termination of a transaction):
* The algorithm to abort the transaction first pauses the channel by
clearing the ACTIVE flag in the CS register, then waits for the PAUSED
flag to clear. Page 49 of the spec documents the latter as follows:
"Indicates if the DMA is currently paused and not transferring data.
This will occur if the active bit has been cleared [...]"
https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
So the function is entering an infinite loop because it is waiting for
PAUSED to clear which is always set due to the function having cleared
the ACTIVE flag. The only thing that's saving it from itself is the
upper bound of 10000 loop iterations.
The code comment says that the intention is to "wait for any current
AXI transfer to complete", so the author probably wanted to check the
WAITING_FOR_OUTSTANDING_WRITES flag instead. Amend the function
accordingly.
* The CS register is only read at the beginning of the function. It
needs to be read again after pausing the channel and before checking
for outstanding writes, otherwise writes which were issued between
the register read at the beginning of the function and pausing the
channel may not be waited for.
* The function seeks to abort the transfer by writing 0 to the NEXTCONBK
register and setting the ABORT and ACTIVE flags. Thereby, the 0 in
NEXTCONBK is sought to be loaded into the CONBLK_AD register. However
experimentation has shown this approach to not work: The CONBLK_AD
register remains the same as before and the CS register contains
0x00000030 (PAUSED | DREQ_STOPS_DMA). In other words, the control
block is not aborted but merely paused and it will be resumed once the
next DMA transaction is started. That is absolutely not the desired
behavior.
A simpler approach is to set the channel's RESET flag instead. This
reliably zeroes the NEXTCONBK as well as the CS register. It requires
less code and only a single MMIO write. This is also what popular
user space DMA drivers do, e.g.:
https://github.com/metachris/RPIO/blob/master/source/c_pwm/pwm.c
Note that the spec is contradictory whether the NEXTCONBK register
is writeable at all. On the one hand, page 41 claims:
"The value loaded into the NEXTCONBK register can be overwritten so
that the linked list of Control Block data structures can be
dynamically altered. However it is only safe to do this when the DMA
is paused."
On the other hand, page 40 specifies:
"Only three registers in each channel's register set are directly
writeable (CS, CONBLK_AD and DEBUG). The other registers (TI,
SOURCE_AD, DEST_AD, TXFR_LEN, STRIDE & NEXTCONBK), are automatically
loaded from a Control Block data structure held in external memory."
If IRQ handlers are threaded (either because CONFIG_PREEMPT_RT_BASE is
enabled or "threadirqs" was passed on the command line) and if system
load is sufficiently high that wakeup latency of IRQ threads degrades,
SPI DMA transactions on the BCM2835 occasionally break like this:
ks8851 spi0.0: SPI transfer timed out
bcm2835-dma 3f007000.dma: DMA transfer could not be terminated
ks8851 spi0.0 eth2: ks8851_rdfifo: spi_sync() failed
The root cause is an assumption made by the DMA driver which is
documented in a code comment in bcm2835_dma_terminate_all():
/*
* Stop DMA activity: we assume the callback will not be called
* after bcm_dma_abort() returns (even if it does, it will see
* c->desc is NULL and exit.)
*/
That assumption falls apart if the IRQ handler bcm2835_dma_callback() is
threaded: A client may terminate a descriptor and issue a new one
before the IRQ handler had a chance to run. In fact the IRQ handler may
miss an *arbitrary* number of descriptors. The result is the following
race condition:
1. A descriptor finishes, its interrupt is deferred to the IRQ thread.
2. A client calls dma_terminate_async() which sets channel->desc = NULL.
3. The client issues a new descriptor. Because channel->desc is NULL,
bcm2835_dma_issue_pending() immediately starts the descriptor.
4. Finally the IRQ thread runs and writes BCM2835_DMA_INT to the CS
register to acknowledge the interrupt. This clears the ACTIVE flag,
so the newly issued descriptor is paused in the middle of the
transaction. Because channel->desc is not NULL, the IRQ thread
finalizes the descriptor and tries to start the next one.
I see two possible solutions: The first is to call synchronize_irq()
in bcm2835_dma_issue_pending() to wait until the IRQ thread has
finished before issuing a new descriptor. The downside of this approach
is unnecessary latency if clients desire rapidly terminating and
re-issuing descriptors and don't have any use for an IRQ callback.
(The SPI TX DMA channel is a case in point.)
A better alternative is to make the IRQ thread recognize that it has
missed descriptors and avoid finalizing the newly issued descriptor.
So first of all, set the ACTIVE flag when acknowledging the interrupt.
This keeps a newly issued descriptor running.
If the descriptor was finished, the channel remains idle despite the
ACTIVE flag being set. However the ACTIVE flag can then no longer be
used to check whether the channel is idle, so instead check whether
the register containing the current control block address is zero
and finalize the current descriptor only if so.
That way, there is no impact on latency and throughput if the client
doesn't care for the interrupt: Only minimal additional overhead is
introduced for non-cyclic descriptors as one further MMIO read is
necessary per interrupt to check for idleness of the channel. Cyclic
descriptors are sped up slightly by removing one MMIO write per
interrupt.
Some of the pipe_buf_release() handlers seem to assume that the pipe is
locked - in particular, anon_pipe_buf_release() accesses pipe->tmp_page
without taking any extra locks. From a glance through the callers of
pipe_buf_release(), it looks like FUSE is the only one that calls
pipe_buf_release() without having the pipe locked.
This bug should only lead to a memory leak, nothing terrible.
In the current code, the codec registration may happen both at the
codec bind time and the end of the controller probe time. In a rare
occasion, they race with each other, leading to Oops due to the still
uninitialized card device.
This patch introduces a simple flag to prevent the codec registration
at the codec bind time as long as the controller probe is going on.
The controller probe invokes snd_card_register() that does the whole
registration task, and we don't need to register each piece
beforehand.
It is normal user behaviour to start, stop, then start a stream
again without closing it. Currently this works for compressed
playback streams but not capture ones.
The states on a compressed capture stream go directly from OPEN to
PREPARED, unlike a playback stream which moves to SETUP and waits
for a write of data before moving to PREPARED. Currently however,
when a stop is sent the state is set to SETUP for both types of
streams. This leaves a capture stream in the situation where a new
start can't be sent as that requires the state to be PREPARED and
a new set_params can't be sent as that requires the state to be
OPEN. The only option being to close the stream, and then reopen.
Correct this issues by allowing snd_compr_drain_notify to set the
state depending on the stream direction, as we already do in
set_params.
Fixes: 49bb6402f1aa ("ALSA: compress_core: Add support for capture streams") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The unbalance of master's promiscuity or allmulti will happen after ifdown
and ifup a slave interface which is in a bridge.
When we ifdown a slave interface , both the 'dsa_slave_close' and
'dsa_slave_change_rx_flags' will clear the master's flags. The flags
of master will be decrease twice.
In the other hand, if we ifup the slave interface again, since the
slave's flags were cleared the 'dsa_slave_open' won't set the master's
flag, only 'dsa_slave_change_rx_flags' that triggered by 'br_add_if'
will set the master's flags. The flags of master is increase once.
Only propagating flag changes when a slave interface is up makes
sure this does not happen. The 'vlan_dev_change_rx_flags' had the
same problem and was fixed, and changes here follows that fix.
Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Rundong Ge <rdong.ge@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When an ethernet frame is padded to meet the minimum ethernet frame
size, the padding octets are not covered by the hardware checksum.
Fortunately the padding octets are usually zero's, which don't affect
checksum. However, we have a switch which pads non-zero octets, this
causes kernel hardware checksum fault repeatedly.
Prior to:
commit '88078d98d1bb ("net: pskb_trim_rcsum() and CHECKSUM_COMPLETE ...")'
skb checksum was forced to be CHECKSUM_NONE when padding is detected.
After it, we need to keep skb->csum updated, like what we do for RXFCS.
However, fixing up CHECKSUM_COMPLETE requires to verify and parse IP
headers, it is not worthy the effort as the packets are so small that
CHECKSUM_COMPLETE can't save anything.
Fixes: 88078d98d1bb ("net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends"), Cc: Eric Dumazet <edumazet@google.com> Cc: Tariq Toukan <tariqt@mellanox.com> Cc: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Broadcom STB chips support a deep sleep mode where all register
contents are lost. Because we were stashing the MagicPacket password
into some of these registers a suspend into that deep sleep then a
resumption would not lead to being able to wake-up from MagicPacket with
password again.
Fix this by keeping a software copy of the password and program it
during suspend.
Fixes: 83e82f4c706b ("net: systemport: add Wake-on-LAN support") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "p" buffer is 0x4000 bytes long. B3_RI_WTO_R1 is 0x190. The value
of "regs->len" is in the 1-0x4000 range. The bug here is that
"regs->len - B3_RI_WTO_R1" can be a negative value which would lead to
memory corruption and an abrupt crash.
Fixes: c3f8be961808 ("[PATCH] skge: expand ethtool debug register dump") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When either "goto wait_interrupted;" or "goto wait_error;"
paths are taken, socket lock has already been released.
This patch fixes following syzbot splat :
WARNING: bad unlock balance detected!
5.0.0-rc4+ #59 Not tainted
-------------------------------------
syz-executor223/8256 is trying to release lock (sk_lock-AF_RXRPC) at:
[<ffffffff86651353>] rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598
but there are no more locks to release!
other info that might help us debug this:
1 lock held by syz-executor223/8256:
#0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline]
#0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: release_sock+0x20/0x1c0 net/core/sock.c:2798
Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Howells <dhowells@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During sendmsg() a cloned skb is saved via dp83640_txtstamp() in
->tx_queue. After the NIC sends this packet, the PHY will reply with a
timestamp for that TX packet. If the cable is pulled at the right time I
don't see that packet. It might gets flushed as part of queue shutdown
on NIC's side.
Once the link is up again then after the next sendmsg() we enqueue
another skb in dp83640_txtstamp() and have two on the list. Then the PHY
will send a reply and decode_txts() attaches it to the first skb on the
list.
No crash occurs since refcounting works but we are one packet behind.
linuxptp/ptp4l usually closes the socket and opens a new one (in such a
timeout case) so those "stale" replies never get there. However it does
not resume normal operation anymore.
Purge old skbs in decode_txts().
Fixes: cb646e2b02b2 ("ptp: Added a clock driver for the National Semiconductor PHYTER.") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of IPv6 pkts, ipv4_csum_ok is 0. Because of this, driver does
not set skb->ip_summed. So IPv6 rx checksum is not offloaded.
Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Avoid warnings like this:
thermal_hwmon.h:29:1: warning: ‘thermal_remove_hwmon_sysfs’ defined but not used [-Wunused-function]
thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
Fixes: 0dd88793aacd ("thermal: hwmon: move hwmon support to single file") Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A bug is present in GDB which causes early string termination when
parsing variables. This has been reported [0], but we should ensure
that we can support at least basic printing of the core kernel strings.
For current gdb version (has been tested with 7.3 and 8.1), 'lx-version'
only prints one character.
(gdb) lx-version
L(gdb)
This can be fixed by casting 'linux_banner' as (char *).
(gdb) lx-version
Linux version 4.19.0-rc1+ (changbin@acer) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #21 SMP Sat Sep 1 21:43:30 CST 2018
load_script() simply truncates bprm->buf and this is very wrong if the
length of shebang string exceeds BINPRM_BUF_SIZE-2. This can silently
truncate i_arg or (worse) we can execute the wrong binary if buf[2:126]
happens to be the valid executable path.
Change load_script() to return ENOEXEC if it can't find '\n' or zero in
bprm->buf. Note that '\0' can come from either
prepare_binprm()->memset() or from kernel_read(), we do not care.
Link: http://lkml.kernel.org/r/20181112160931.GA28463@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Ben Woodard <woodard@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The ep->ovflist is a secondary ready-list to temporarily store events
that might occur when doing sproc without holding the ep->wq.lock. This
accounts for every time we check for ready events and also send events
back to userspace; both callbacks, particularly the latter because of
copy_to_user, can account for a non-trivial time.
As such, the unlikely() check to see if the pointer is being used, seems
both misleading and sub-optimal. In fact, we go to an awful lot of
trouble to sync both lists, and populating the ovflist is far from an
uncommon scenario.
For example, profiling a concurrent epoll_wait(2) benchmark, with
CONFIG_PROFILE_ANNOTATED_BRANCHES shows that for a two threads a 33%
incorrect rate was seen; and when incrementally increasing the number of
epoll instances (which is used, for example for multiple queuing load
balancing models), up to a 90% incorrect rate was seen.
Similarly, by deleting the prediction, 3% throughput boost was seen
across incremental threads.
Link: http://lkml.kernel.org/r/20181108051006.18751-4-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jason Baron <jbaron@akamai.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Based on commit 401c636a0eeb ("kernel/hung_task.c: show all hung tasks
before panic"), we could get the call stack of hung task.
However, if the console loglevel is not high, we still can not see the
useful panic information in practice, and in most cases users don't set
console loglevel to high level.
This patch is to force console verbose before system panic, so that the
real useful information can be seen in the console, instead of being
like the following, which doesn't have hung task information.
INFO: task init:1 blocked for more than 120 seconds.
Tainted: G U W 4.19.0-quilt-2e5dc0ac-g51b6c21d76cc #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Kernel panic - not syncing: hung_task: blocked tasks
CPU: 2 PID: 479 Comm: khungtaskd Tainted: G U W 4.19.0-quilt-2e5dc0ac-g51b6c21d76cc #1
Call Trace:
dump_stack+0x4f/0x65
panic+0xde/0x231
watchdog+0x290/0x410
kthread+0x12c/0x150
ret_from_fork+0x35/0x40
reboot: panic mode set: p,w
Kernel Offset: 0x34000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
Link: http://lkml.kernel.org/r/27240C0AC20F114CBF8149A2696CBE4A6015B675@SHSMSX101.ccr.corp.intel.com Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
There are three processing functions dealing with digital parameters,
__do_proc_dointvec/__do_proc_douintvec/__do_proc_doulongvec_minmax.
This patch deals with __do_proc_doulongvec_minmax, just as
__do_proc_dointvec does, adding a check for parameters 'left'. In
__do_proc_douintvec, its code implementation explicitly does not support
multiple inputs.
static int __do_proc_douintvec(...){
...
/*
* Arrays are not supported, keep this simple. *Do not* add
* support for them.
*/
if (vleft != 1) {
*lenp = 0;
return -EINVAL;
}
...
}
So, just __do_proc_doulongvec_minmax has the problem. And most use of
proc_doulongvec_minmax/proc_doulongvec_ms_jiffies_minmax just have one
parameter.
Link: http://lkml.kernel.org/r/1544081775-15720-1-git-send-email-cheng.lin130@zte.com.cn Signed-off-by: Cheng Lin <cheng.lin130@zte.com.cn> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
check_hung_uninterruptible_tasks() is currently calling rcu_lock_break()
for every 1024 threads. But check_hung_task() is very slow if printk()
was called, and is very fast otherwise.
If many threads within some 1024 threads called printk(), the RCU grace
period might be extended enough to trigger RCU stall warnings.
Therefore, calling rcu_lock_break() for every some fixed jiffies will be
safer.
Link: http://lkml.kernel.org/r/1544800658-11423-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Vitaly Kuznetsov <vkuznets@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 <sashal@kernel.org>
First correct the edge case to return the last element if we're
outside the range, rather than at the last element, so that
interpolation is not omitted for points between the two last entries in
the table.
Then correct the formula to perform linear interpolation based the two
points surrounding the read ADC value. The indices for temp are kept as
"hi" and "lo" to pair with the adc indices, but there's no requirement
that the temperature is provided in descendent order. mult_frac() is
used to prevent issues with overflowing the int.
If you have a CPU that fails to round up and then run 'btc' you'll end
up crashing in kdb becaue we dereferenced NULL. Let's add a check.
It's wise to also set the task to NULL when leaving the debugger so
that if we fail to round up on a later entry into the debugger we
won't backtrace a stale task.
Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
By defaul of-based thermal driver do not enable hwmon.
This patch does this explicitly, so that the temperature can be read
through the common hwmon sysfs.
When the block device is opened with FMODE_EXCL, ref_count is set to -1.
This value doesn't get reset when the device is closed which means the
device cannot be opened again. Fix this by checking for refcount <= 0
in the release method.
Reported-and-tested-by: Stan Johnson <userm57@yahoo.com> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
In probe_gdrom(), the buffer pointed by 'gd.cd_info' is allocated through
kzalloc() and is used to hold the information of the gdrom device. To
register and unregister the device, the pointer 'gd.cd_info' is passed to
the functions register_cdrom() and unregister_cdrom(), respectively.
However, this buffer is not freed after it is used, which can cause a
memory leak bug.
This patch simply frees the buffer 'gd.cd_info' in exit_gdrom() to fix the
above issue.
Included file path was hard-wired in the ocfs2 makefile, which might
causes some confusion when compiling ocfs2 as an external module.
Say if we compile ocfs2 module as following.
cp -r /kernel/tree/fs/ocfs2 /other/dir/ocfs2
cd /other/dir/ocfs2
make -C /path/to/kernel_source M=`pwd` modules
Acutally, the compiler wil try to find included file in
/kernel/tree/fs/ocfs2, rather than the directory /other/dir/ocfs2.
To fix this little bug, we introduce the var $(src) provided by kbuild.
$(src) means the absolute path of the running kbuild file.
Link: http://lkml.kernel.org/r/20181108085546.15149-1-lchen@suse.com Signed-off-by: Larry Chen <lchen@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Changwei Ge <ge.changwei@h3c.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
For sync io read in ocfs2_read_blocks_sync(), first clear bh uptodate flag
and submit the io, second wait io done, last check whether bh uptodate, if
not return io error.
If two sync io for the same bh were issued, it could be the first io done
and set uptodate flag, but just before check that flag, the second io came
in and cleared uptodate, then ocfs2_read_blocks_sync() for the first io
will return IO error.
Indeed it's not necessary to clear uptodate flag, as the io end handler
end_buffer_read_sync() will set or clear it based on io succeed or failed.
The following message was found from a nfs server but the underlying
storage returned no error.
[4106438.567376] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2780 ERROR: read block 1238823695 failed -5
[4106438.567569] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2812 ERROR: status = -5
[4106438.567611] (nfsd,7146,3):ocfs2_test_inode_bit:2894 ERROR: get alloc slot and bit failed -5
[4106438.567643] (nfsd,7146,3):ocfs2_test_inode_bit:2932 ERROR: status = -5
[4106438.567675] (nfsd,7146,3):ocfs2_get_dentry:94 ERROR: test inode bit failed -5
Same issue in non sync read ocfs2_read_blocks(), fixed it as well.
Link: http://lkml.kernel.org/r/20181121020023.3034-4-junxiao.bi@oracle.com Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Changwei Ge <ge.changwei@h3c.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Jun Piao <piaojun@huawei.com> Cc: Mark Fasheh <mfasheh@versity.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
leads to interested results where not only the leading "." gets stripped
from the displayed paths, but also anywhere in the string, displaying
something like:
This fixes the case where all mount options specified are consumed by an
LSM and all that's left is an empty string. In this case cgroupfs should
accept the string and not fail.
How to reproduce (with SELinux enabled):
# umount /sys/fs/cgroup/unified
# mount -o context=system_u:object_r:cgroup_t:s0 -t cgroup2 cgroup2 /sys/fs/cgroup/unified
mount: /sys/fs/cgroup/unified: wrong fs type, bad option, bad superblock on cgroup2, missing codepage or helper program, or other error.
# dmesg | tail -n 1
[ 31.575952] cgroup: cgroup2: unknown option ""
Fixes: 67e9c74b8a87 ("cgroup: replace __DEVEL__sane_behavior with cgroup2 fs type")
[NOTE: should apply on top of commit 5136f6365ce3 ("cgroup: implement "nsdelegate" mount option"), older versions need manual rebase] Suggested-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
projects / linux-stable / log