This patch fixes vulnerability CVE-2016-2085. The problem exists
because the vm_verify_hmac() function includes a use of memcmp().
Unfortunately, this allows timing side channel attacks; specifically
a MAC forgery complexity drop from 2^128 to 2^12. This patch changes
the memcmp() to the cryptographically safe crypto_memneq().
Reported-by: Xiaofei Rex Guo <xiaofei.rex.guo@intel.com> Signed-off-by: Ryan Ware <ware@linux.intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Cc: Moritz Muehlenhoff <jmm@inutil.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
/sys/class/net/<interface>/operstate for an active qeth network
interface offen shows "unknown", which translates to "state UNKNOWN
in output of "ip link show". It is caused by a missing initialization
of the __LINK_STATE_NOCARRIER bit in the net_device state field.
This patch adds a netif_carrier_off() invocation when creating the
net_device for a qeth device.
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reference-ID: Bugzilla 133209 Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
If the ASN.1 decoder is asked to parse a sequence of objects, non-optional
matches get skipped if there's no more data to be had rather than a
data-overrun error being reported.
This is due to the code segment that decides whether to skip optional
matches (ie. matches that could get ignored because an element is marked
OPTIONAL in the grammar) due to a lack of data also skips non-optional
elements if the data pointer has reached the end of the buffer.
This can be tested with the data decoder for the new RSA akcipher algorithm
that takes three non-optional integers. Currently, it skips the last
integer if there is insufficient data.
Without the fix, #defining DEBUG in asn1_decoder.c will show something
like:
The next_op line for pc=8/13 should be followed by a match line.
This is not exploitable for X.509 certificates by means of shortening the
message and fixing up the ASN.1 CONS tags because:
(1) The relevant records being built up are cleared before use.
(2) If the message is shortened sufficiently to remove the public key, the
ASN.1 parse of the RSA key will fail quickly due to a lack of data.
(3) Extracted signature data is either turned into MPIs (which cope with a
0 length) or is simpler integers specifying algoritms and suchlike
(which can validly be 0); and
(4) The AKID and SKID extensions are optional and their removal is handled
without risking passing a NULL to asymmetric_key_generate_id().
(5) If the certificate is truncated sufficiently to remove the subject,
issuer or serialNumber then the ASN.1 decoder will fail with a 'Cons
stack underflow' return.
This is not exploitable for PKCS#7 messages by means of removal of elements
from such a message from the tail end of a sequence:
(1) Any shortened X.509 certs embedded in the PKCS#7 message are survivable
as detailed above.
(2) The message digest content isn't used if it shows a NULL pointer,
similarly, the authattrs aren't used if that shows a NULL pointer.
(3) A missing signature results in a NULL MPI - which the MPI routines deal
with.
(4) If data is NULL, it is expected that the message has detached content and
that is handled appropriately.
(5) If the serialNumber is excised, the unconditional action associated
with it will pick up the containing SEQUENCE instead, so no NULL
pointer will be seen here.
If both the issuer and the serialNumber are excised, the ASN.1 decode
will fail with an 'Unexpected tag' return.
In either case, there's no way to get to asymmetric_key_generate_id()
with a NULL pointer.
(6) Other fields are decoded to simple integers. Shortening the message
to omit an algorithm ID field will cause checks on this to fail early
in the verification process.
This can also be tested by snipping objects off of the end of the ASN.1 stream
such that mandatory tags are removed - or even from the end of internal
SEQUENCEs. If any mandatory tag is missing, the error EBADMSG *should* be
produced. Without this patch ERANGE or ENOPKG might be produced or the parse
may apparently succeed, perhaps with ENOKEY or EKEYREJECTED being produced
later, depending on what gets snipped.
Just snipping off the final BIT_STRING or OCTET_STRING from either sample
should be a start since both are mandatory and neither will cause an EBADMSG
without the patches
Reported-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Moritz Muehlenhoff <jmm@inutil.org>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The visor driver crashes in clie_5_attach() when a specially crafted USB
device without bulk-out endpoint is detected. This fix adds a check that
the device has proper configuration expected by the driver.
Reported-by: Ralf Spenneberg <ralf@spenneberg.net> Signed-off-by: Vladis Dronov <vdronov@redhat.com> Fixes: cfb8da8f69b8 ("USB: visor: fix initialisation of UX50/TH55 devices") Signed-off-by: Johan Hovold <johan@kernel.org> Cc: Moritz Muehlenhoff <jmm@inutil.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
ioctl(TIOCGETD) retrieves the line discipline id directly from the
ldisc because the line discipline id (c_line) in termios is untrustworthy;
userspace may have set termios via ioctl(TCSETS*) without actually
changing the line discipline via ioctl(TIOCSETD).
However, directly accessing the current ldisc via tty->ldisc is
unsafe; the ldisc ptr dereferenced may be stale if the line discipline
is changing via ioctl(TIOCSETD) or hangup.
Wait for the line discipline reference (just like read() or write())
to retrieve the "current" line discipline id.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Moritz Muehlenhoff <jmm@inutil.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The usbvision driver crashes when a specially crafted usb device with invalid
number of interfaces or endpoints is detected. This fix adds checks that the
device has proper configuration expected by the driver.
The critical section protected by usbhid->lock in hid_ctrl() is too
big and because of this it causes a recursive deadlock. "Too big" means
the case statement and the call to hid_input_report() do not need to be
protected by the spinlock (no URB operations are done inside them).
The deadlock happens because in certain rare cases drivers try to grab
the lock while handling the ctrl irq which grabs the lock before them
as described above. For example newer wacom tablets like 056a:033c try
to reschedule proximity reads from wacom_intuos_schedule_prox_event()
calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report()
which tries to grab the usbhid lock already held by hid_ctrl().
There are two ways to get out of this deadlock:
1. Make the drivers work "around" the ctrl critical region, in the
wacom case for ex. by delaying the scheduling of the proximity read
request itself to a workqueue.
2. Shrink the critical region so the usbhid lock protects only the
instructions which modify usbhid state, calling hid_input_report()
with the spinlock unlocked, allowing the device driver to grab the
lock first, finish and then grab the lock afterwards in hid_ctrl().
This patch implements the 2nd solution.
Signed-off-by: Ioan-Adrian Ratiu <adi@adirat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Cc: Jason Gerecke <killertofu@gmail.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Under some conditions, CIFS can repeatedly call the cifs_dbg() logging
wrapper. If done rapidly enough, the console framebuffer can softlockup
or "rcu_sched self-detected stall". Apply the built-in log ratelimiters
to prevent such hangs.
Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
kernel/uid16.c: In function 'SYSC_setgroups16':
kernel/uid16.c:184:2: error: implicit declaration of function 'groups_alloc'
kernel/uid16.c:184:13: warning: assignment makes pointer from integer without a cast
openrisc shouldn't be setting CONFIG_UID16 when CONFIG_MULTIUSER=n.
Fixes: 2813893f8b197a1 ("kernel: conditionally support non-root users, groups and capabilities") Reported-by: Fengguang Wu <fengguang.wu@gmail.com> Cc: Iulia Manda <iulia.manda21@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
As reported by Michal Simek, building an ARM64 kernel with CONFIG_UID16
disabled currently fails because the system call table still needs to
reference the individual function entry points that are provided by
kernel/sys_ni.c in this case, and the declarations are hidden inside
of #ifdef CONFIG_UID16:
arch/arm64/include/asm/unistd32.h:57:8: error: 'sys_lchown16' undeclared here (not in a function)
__SYSCALL(__NR_lchown, sys_lchown16)
I believe this problem only exists on ARM64, because older architectures
tend to not need declarations when their system call table is built
in assembly code, while newer architectures tend to not need UID16
support. ARM64 only uses these system calls for compatibility with
32-bit ARM binaries.
This changes the CONFIG_UID16 check into CONFIG_HAVE_UID16, which is
set unconditionally on ARM64 with CONFIG_COMPAT, so we see the
declarations whenever we need them, but otherwise the behavior is
unchanged.
Fixes: af1839eb4bd4 ("Kconfig: clean up the long arch list for the UID16 config option") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Hop limit value wasn't copied from attributes when ah was created.
This may influence packets for unconnected services to get dropped in
routers when endpoints are not in the same subnet.
Fixes: fa417f7b520e ("IB/mlx4: Add support for IBoE") Signed-off-by: Matan Barak <matanb@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Currently, pr_debug and pr_devel will not elide function call arguments
appearing in calls to the no_printk for these macros. This is because
all side effects must be honored before proceeding to the 0-value
assignment in no_printk.
The behavior is contrary to documentation found in the CodingStyle and
the header file where these functions are declared.
This patch corrects that behavior by shunting out the call to no_printk
completely. The format string is still checked by gcc for correctness,
but no code seems to be emitted in common cases.
[akpm@linux-foundation.org: remove braces, per Joe] Fixes: 5264f2f75d86 ("include/linux/printk.h: use and neaten no_printk") Signed-off-by: Aaron Conole <aconole@redhat.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Joe Perches <joe@perches.com> 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: Luis Henriques <luis.henriques@canonical.com>
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.
But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_orig_node_free_ref.
Fixes: 72822225bd41 ("batman-adv: Fix rcu_barrier() miss due to double call_rcu() in TT code") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.
But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_hardif_free_ref.
Fixes: 89652331c00f ("batman-adv: split tq information in neigh_node struct") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.
But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_neigh_ifinfo_free_ref.
Fixes: 89652331c00f ("batman-adv: split tq information in neigh_node struct") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.
But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_neigh_node_free_ref.
Fixes: 89652331c00f ("batman-adv: split tq information in neigh_node struct") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
It is not allowed to free the memory of an object which is part of a list
which is protected by rcu-read-side-critical sections without making sure
that no other context is accessing the object anymore. This usually happens
by removing the references to this object and then waiting until the rcu
grace period is over and no one (allowedly) accesses it anymore.
But the _now functions ignore this completely. They free the object
directly even when a different context still tries to access it. This has
to be avoided and thus these functions must be removed and all functions
have to use batadv_orig_ifinfo_free_ref.
Fixes: 7351a4822d42 ("batman-adv: split out router from orig_node") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This patch fixes a potential memory leak which can occur once an
originator times out. On timeout the according global translation table
entry might not get purged correctly. Furthermore, the non purged TT
entry will cause its orig-node to leak, too. Which additionally can lead
to the new multicast optimization feature not kicking in because of a
therefore bogus counter.
In detail: The batadv_tt_global_entry->orig_list holds the reference to
the orig-node. Usually this reference is released after
BATADV_PURGE_TIMEOUT through: _batadv_purge_orig()->
batadv_purge_orig_node()->batadv_update_route()->_batadv_update_route()->
batadv_tt_global_del_orig() which purges this global tt entry and
releases the reference to the orig-node.
However, if between two batadv_purge_orig_node() calls the orig-node
timeout grew to 2*BATADV_PURGE_TIMEOUT then this call path isn't
reached. Instead the according orig-node is removed from the
originator hash in _batadv_purge_orig(), the batadv_update_route()
part is skipped and won't be reached anymore.
Fixing the issue by moving batadv_tt_global_del_orig() out of the rcu
callback.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Acked-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The batadv_nc_node_free_ref function uses call_rcu to delay the free of the
batadv_nc_node object until no (already started) rcu_read_lock is enabled
anymore. This makes sure that no context is still trying to access the
object which should be removed. But batadv_nc_node also contains a
reference to orig_node which must be removed.
The reference drop of orig_node was done in the call_rcu function
batadv_nc_node_free_rcu but should actually be done in the
batadv_nc_node_release function to avoid nested call_rcus. This is
important because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will
not detect the inner call_rcu as relevant for its execution. Otherwise this
barrier will most likely be inserted in the queue before the callback of
the first call_rcu was executed. The caller of rcu_barrier will therefore
continue to run before the inner call_rcu callback finished.
Fixes: d56b1705e28c ("batman-adv: network coding - detect coding nodes and remove these after timeout") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The batadv_claim_free_ref function uses call_rcu to delay the free of the
batadv_bla_claim object until no (already started) rcu_read_lock is enabled
anymore. This makes sure that no context is still trying to access the
object which should be removed. But batadv_bla_claim also contains a
reference to backbone_gw which must be removed.
The reference drop of backbone_gw was done in the call_rcu function
batadv_claim_free_rcu but should actually be done in the
batadv_claim_release function to avoid nested call_rcus. This is important
because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will not
detect the inner call_rcu as relevant for its execution. Otherwise this
barrier will most likely be inserted in the queue before the callback of
the first call_rcu was executed. The caller of rcu_barrier will therefore
continue to run before the inner call_rcu callback finished.
Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
After promisc mode management was introduced a bridge device could do
dev_set_promiscuity from its ndo_change_rx_flags() callback which in
turn can be called after the bridge's addr_list_lock has been taken
(e.g. by dev_uc_add). This causes a false positive lockdep splat because
the port interfaces' addr_list_lock is taken when br_manage_promisc()
runs after the bridge's addr list lock was already taken.
To remove the false positive introduce a custom bridge addr_list_lock
class and set it on bridge init.
A simple way to reproduce this is with the following:
$ brctl addbr br0
$ ip l add l br0 br0.100 type vlan id 100
$ ip l set br0 up
$ ip l set br0.100 up
$ echo 1 > /sys/class/net/br0/bridge/vlan_filtering
$ brctl addif br0 eth0
Splat:
[ 43.684325] =============================================
[ 43.684485] [ INFO: possible recursive locking detected ]
[ 43.684636] 4.4.0-rc8+ #54 Not tainted
[ 43.684755] ---------------------------------------------
[ 43.684906] brctl/1187 is trying to acquire lock:
[ 43.685047] (_xmit_ETHER){+.....}, at: [<ffffffff8150169e>] dev_set_rx_mode+0x1e/0x40
[ 43.685460] but task is already holding lock:
[ 43.685618] (_xmit_ETHER){+.....}, at: [<ffffffff815072a7>] dev_uc_add+0x27/0x80
[ 43.686015] other info that might help us debug this:
[ 43.686316] Possible unsafe locking scenario:
CC: Vlad Yasevich <vyasevic@redhat.com> CC: Stephen Hemminger <stephen@networkplumber.org> CC: Bridge list <bridge@lists.linux-foundation.org> CC: Andy Gospodarek <gospo@cumulusnetworks.com> CC: Roopa Prabhu <roopa@cumulusnetworks.com> Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.") Reported-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
If we return 1 here, then the caller treats it as an error and returns
-EINVAL. It causes a static checker warning to treat positive returns
as an error.
Fixes: 1aba86d67f34 ('Btrfs: fix easily get into ENOSPC in mixed case') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The SD card specification allows cards to error out a SWITCH command
where the requested function in a group is not supported. The spec
provides for a set of capabilities which indicate which functions are
supported.
In the case of the power limit, requesting an unsupported power level
via the SWITCH command fails, resulting in the power level remaining at
the power-on default of 0.72W, even though the host and card may support
higher powers levels.
This has been seen with SanDisk 8GB cards, which support the default
0.72W and 1.44W (200mA and 400mA) in combination with an iMX6 host,
supporting up to 2.88W (800mA). This currently causes us to try to set
a power limit function value of '3' (2.88W) which the card errors out
on, and thereby causes the power level to remain at 0.72W rather than
the desired 1.44W.
Arrange to limit the selected current limit by the capabilities reported
by the card to avoid the SWITCH command failing. Select the highest
current limit that the host and card combination support.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Fixes: a39ca6ae0a08 ("mmc: core: Simplify and fix for SD switch processing") Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
When first SYNACK is sent, we already hold rcu_read_lock(), but this
is not true if a SYNACK is retransmitted, as a timer (soft) interrupt
does not hold rcu_read_lock()
Fixes: 45f6fad84cc30 ("ipv6: add complete rcu protection around np->opt") Reported-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Fix build error by generating elfcore.o only when ELF_CORE (depending on
COREDUMP) is selected:
arch/x86/um/built-in.o: In function `elf_core_write_extra_phdrs':
(.text+0x3e62): undefined reference to `dump_emit'
arch/x86/um/built-in.o: In function `elf_core_write_extra_data':
(.text+0x3eef): undefined reference to `dump_emit'
Fixes: 5d2acfc7b974 ("kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT") Signed-off-by: Mickaël Salaün <mic@digikod.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Michal Marek <mmarek@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The kerneldoc for request_firmware_nowait() says that it may call the
provided cont() callback with @fw == NULL, if the firmware request
fails. However, this is not the case when called with an empty string
(""). This case is short-circuited by the 'name[0] == '\0'' check
introduced in commit 471b095dfe0d ("firmware_class: make sure fw requests
contain a name"), so _request_firmware() never gets to set the fw to
NULL.
Noticed while using the new 'trigger_async_request' testing hook:
# printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request
[ 32.126322] test_firmware: loading ''
[ 32.129995] test_firmware: failed to async load firmware
-bash: printf: write error: No such device
Fixes: 471b095dfe0d ("firmware_class: make sure fw requests contain a name") Signed-off-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Ming Lei <ming.lei@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Writing 0 length data into test_power makes it access an invalid array
location and kill the system.
Fixes: f17ef9b2d ("power: Make test_power driver more dynamic.") Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Sebastian Reichel <sre@kernel.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This patch fixes a bug in the filter_events() function.
The patch fixes the bug whereby if some mappings did not
exist, e.g., STALLED_CYCLES_FRONTEND, then any event after it
in the attrs array would disappear from the published list of
events in /sys/devices/cpu/events. This could be verified
easily on any system post SNB (which do not publish
STALLED_CYCLES_FRONTEND):
$ ./perf stat -e cycles,ref-cycles true
Performance counter stats for 'true':
1,217,348 cycles
<not supported> ref-cycles
The problem is that in filter_events() there is an assumption
that the argument (attrs) is organized in increasing continuous
event indexes related to the event_map(). But if we remove the
non-supported events by shifing the position in the array, then
the lookup x86_pmu.event_map() needs to compensate for it, otherwise
we are looking up the wrong index. This patch corrects this problem
by compensating for the deleted events and with that ref-cycles
reappears (here shown on Haswell):
$ perf stat -e ref-cycles,cycles true
Performance counter stats for 'true':
4,525,910 ref-cycles
1,064,920 cycles
0.002943888 seconds time elapsed
Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: jolsa@kernel.org Cc: kan.liang@intel.com Fixes: 8300daa26755 ("perf/x86: Filter out undefined events from sysfs events attribute") Link: http://lkml.kernel.org/r/1449516805-6637-1-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
menu_is_visible() is a bool function and should use boolean return
values. "no" is a tristate value which happens to also have a value
of 0, but we should nevertheless use the right symbol for it.
This is a very minor cleanup with no semantic change.
Fixes: 86e187ff9 ("kconfig: add an option to determine a menu's visibility") Cc: Arnaud Lacombe <lacombar@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Commit 984d74a72076a1 ("sysrq: rcu-ify __handle_sysrq") replaced
spin_lock_irqsave() calls with rcu_read_lock() calls in sysrq. Since
rcu_read_lock() does not disable preemption, faulthandler_disabled() in
__do_page_fault() in x86/fault.c returns false. When the code later calls
might_sleep() in the pagefault handler, we get the following warning:
BUG: sleeping function called from invalid context at ../arch/x86/mm/fault.c:1187
in_atomic(): 0, irqs_disabled(): 0, pid: 4706, name: bash
Preemption disabled at:[<ffffffff81484339>] printk+0x48/0x4a
To fix this, we release the RCU read lock before we crash.
Tested this patch on linux 3.18 by booting off one of our boards.
Fixes: 984d74a72076a1 ("sysrq: rcu-ify __handle_sysrq") Signed-off-by: Ani Sinha <ani@arista.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This was meant to print base address and entry count; make it do so
again.
Fixes: 37868fe113ff "x86/ldt: Make modify_ldt synchronous" Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Andy Lutomirski <luto@kernel.org> Link: http://lkml.kernel.org/r/56797D8402000078000C24F0@prv-mh.provo.novell.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
In case of an invalid pin value bcm2835_pctl_dt_node_to_map()
would leak the pull configs of already assigned pins.
So avoid this by calling the free map function in error case.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Fixes: e1b2dc70cd5b ("pinctrl: add bcm2835 driver") Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[ luis: backported to 3.16:
- file rename: drivers/pinctrl/bcm/pinctrl-bcm2835.c ->
drivers/pinctrl/pinctrl-bcm2835.c ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The commit d7ba858a7f7a (ALSA: fm801: implement TEA575x tuner autodetection)
brings autodetection to the driver. However the autodetection algorithm misses
the TUNER_ONLY bit if it is supplied by the user.
Thus, user gets weird messages and no card registered.
snd_fm801 0000:0d:01.0: detected TEA575x radio type SF64-PCR
snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
...
snd_fm801 0000:0d:01.0: AC'97 0 does not respond - RESET
snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
snd_fm801 0000:0d:01.0: AC'97 interface is busy (1)
snd_fm801 0000:0d:01.0: AC'97 0 access is not valid [0x0], removing mixer.
snd_fm801: probe of 0000:0d:01.0 failed with error -5
Do a copy of TUNER_ONLY bit to be applied after autodetection is done.
Fixes: d7ba858a7f7a (ALSA: fm801: implement TEA575x tuner autodetection) Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Nobody uses the get_platform_nandchip() helper function which is supposed
to return a pointer to a platform_nand_chip struct from an mtd_info
pointer.
Moreover, this function is buggy since the introduction of the plat_nand
layer (chip->priv is now storing a pointer to an intermediate
plat_nand_data structure allocated in plat_nand_probe(), and we have no
way to retrieve a pointer to the provided platform_nand_chip struct from
this plat_nand_data pointer).
While we are at it, remove the useless (and buggy, since it's pointing to
something stored on the stack) data->chip.priv assignment.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Fixes: 711fdf627ce1 ("[MTD] [NAND] platform NAND driver: add driver") Cc: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Unregister the NAND device from the NAND subsystem when removing a denali
NAND controller, otherwise the MTD attached to the NAND device is still
exposed by the MTD layer, and accesses to this device will likely crash
the system.
Fixes: 2a0a288ec258 ("mtd: denali: split the generic driver and PCI layer") Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Dinh Nguyen <dinguyen@opensource.altera.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
src_ssync_features field is only 1 byte large, and the 4th reserved area
is actually 8 bytes large.
Fixes: d1e1f4e42b5 ("mtd: nand: add support for reading ONFI parameters from NAND device") Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
We check for overflow here, but we don't check for underflow so it
causes a static checker warning.
Fixes: fb9987d0f748 ('ath9k_htc: Support for AR9271 chipset.') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
quadfs_pll_fs660c32_round_rate prints a few structure members
that are never initialized, and also doesn't print the only one
it cares about. We get a gcc warning about the ones that
are printed:
clk/st/clkgen-fsyn.c:560:93: warning: 'params.sdiv' may be used uninitialized in this function
clk/st/clkgen-fsyn.c:560:93: warning: 'params.mdiv' may be used uninitialized in this function
clk/st/clkgen-fsyn.c:560:93: warning: 'params.pe' may be used uninitialized in this function
clk/st/clkgen-fsyn.c:560:93: warning: 'params.nsdiv' may be used uninitialized in this function
This changes the code to no longer print uninitialized data, and
for good measure it also prints the ndiv member that is being
set.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 5f7aa9071e93 ("clk: st: Support for QUADFS inside ClockGenB/C/D/E/F") Acked-by: Gabriel Fernandez <gabriel.fernandez@linaro.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The initio driver has for many years had two copies of the
same module device table. One of them is also used for registering
the other driver, the other one is entirely useless after the
large scale cleanup that Alan Cox did back in 2007.
The compiler warns about this whenever the driver is built-in:
drivers/scsi/initio.c:131:29: warning: 'i91u_pci_devices' defined but not used [-Wunused-variable]
This removes the extraneous table and the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 72d39fea901 ("[SCSI] initio: Convert into a real Linux driver and update to modern style") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
rc-main mistakenly uses #ifdef MODULE to determine whether it should
load the rc keymap modules. This symbol is only defined if rc-main
is being built as a module itself, and bears no relation to whether
the rc keymaps are modules.
Fix this to use CONFIG_MODULES instead.
Fixes: 631493ecacd8 ("[media] rc-core: merge rc-map.c into rc-main.c") Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Currently when allocating a framebuffer fails, the gem object gets
unrefed at the bottom of the call stack in __intel_framebuffer_create,
not where it gets refed, which is in intel_framebuffer_create_for_mode
(via i915_gem_alloc_object) and in intel_user_framebuffer_create
(via drm_gem_object_lookup).
This invites mistakes: __intel_framebuffer_create is also called from
intelfb_alloc, and as discovered by Tvrtko Ursulin, a double unref
was introduced there with a8bb6818270c ("drm/i915: Fix error path leak
in fbdev fb allocation").
As suggested by Ville Syrjälä, fix the double unref and improve code
clarity by moving the unref away from __intel_framebuffer_create to
where the gem object gets refed.
Based on Tvrtko Ursulin's original v2.
v3: On fb alloc failure, unref gem object where it gets refed,
fix double unref in separate commit (Ville Syrjälä)
v4: Lock struct_mutex on unref (Chris Wilson)
v5: Rebase on drm-intel-nightly 2015y-09m-01d-09h-06m-08s UTC,
rephrase commit message (Jani Nicula)
Since a8bb6818270c __intel_framebuffer_create() is called
with struct_mutex held, so it should use drm_gem_object_unreference()
instead of drm_gem_object_unreference_unlocked().
Found by Linux Driver Verification project (linuxtesting.org).
Like the Yoga 900 models the Lenovo Yoga 700 does not have a
hw rfkill switch, and trying to read the hw rfkill switch through the
ideapad module causes it to always reported blocking breaking wifi.
This commit adds the Lenovo Yoga 700 to the no_hw_rfkill dmi list, fixing
the wifi breakage.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1295272 Tested-by: <dinyar.rabady+spam@gmail.com> Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
NFS on a 2 node ocfs2 cluster each node exporting dir. The lock causing
the hang is the global bit map inode lock. Node 1 is master, has the
lock granted in PR mode; Node 2 is in the converting list (PR -> EX).
There are no holders of the lock on the master node so it should
downconvert to NL and grant EX to node 2 but that does not happen.
BLOCKED + QUEUED in lock res are set and it is on osb blocked list.
Threads are waiting in __ocfs2_cluster_lock on BLOCKED. One thread
wants EX, rest want PR. So it is as though the downconvert thread needs
to be kicked to complete the conv.
The hang is caused by an EX req coming into __ocfs2_cluster_lock on the
heels of a PR req after it sets BUSY (drops l_lock, releasing EX
thread), forcing the incoming EX to wait on BUSY without doing anything.
PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> PR,
queues ast.
At this time, upconvert (PR ->EX) arrives from node 2, finds conflict
with node 1 lock in PR, so the lock res is put on dlm thread's dirty
listt.
After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till
awoken by ast.
Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, in
that order. dlm_shuffle_lists ques a bast on behalf of node 2 (which
will be run by dlm_thread right after the ast). ast does its part, sets
UPCONVERT_FINISHING, clears BUSY and wakes its waiters. Next,
dlm_thread runs bast. It sets BLOCKED and kicks dc thread. dc thread
runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing
anything and reques.
Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead
of PR, it wakes up first, finds BLOCKED set and skips doing anything but
clearing UPCONVERT_FINISHING (which was actually "meant" for the PR
thread), and this time waits on BLOCKED. Next, the PR thread comes out
of wait but since UPCONVERT_FINISHING is not set, it skips updating the
l_ro_holders and goes straight to wait on BLOCKED. So there, we have a
hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock res in osb
blocked list. Only when dc thread is awoken, it will run
ocfs2_unblock_lock and things will unhang.
One way to fix this is to wake the dc thread on the flag after clearing
UPCONVERT_FINISHING
Orabug: 20933419 Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Eric Ren <zren@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Currently ALSA timer device doesn't take the disconnection into
account very well; it merely unlinks the timer device at disconnection
callback but does nothing else. Because of this, when an application
accessing the timer device is disconnected, it may release the
resource before actually closed. In most cases, it results in a
warning message indicating a leftover timer instance like:
ALSA: timer xxxx is busy?
But basically this is an open race.
This patch tries to address it. The strategy is like other ALSA
devices: namely,
- Manage card's refcount at each open/close
- Wake up the pending tasks at disconnection
- Check the shutdown flag appropriately at each possible call
Note that this patch has one ugly hack to handle the wakeup of pending
tasks. It'd be cleaner to introduce a new disconnect op to
snd_timer_instance ops. But since it would lead to internal ABI
breakage and it eventually increase my own work when backporting to
stable kernels, I took a different path to implement locally in
timer.c. A cleanup patch will follow at next for 4.5 kernel.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=109431 Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This patch is a iscsi-target specific bug-fix for a dead-lock
that can occur during explicit struct se_node_acl->acl_group
se_session deletion via configfs rmdir(2), when iscsi-target
time2retain timer is still active.
It changes iscsi-target to obtain se_portal_group->session_lock
internally using spin_in_locked() to check for the specific
se_node_acl configfs shutdown rmdir(2) case.
Note this patch is intended for stable, and the subsequent
v4.5-rc patch converts target_core_tpg.c to use proper
se_sess->sess_kref reference counting for both se_node_acl
deletion + se_node_acl->queue_depth se_session restart.
Reported-by:: Sagi Grimberg <sagig@mellanox.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Andy Grover <agrover@redhat.com> Cc: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
One of the newest ideapad models also lacks a physical hw rfkill switch,
and trying to read the hw rfkill switch through the ideapad module
causes it to always reported blocking breaking wifi.
Fix it by adding this model to the DMI list.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1286293 Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The current code is problematic when the QP creation and ipoib is used to
support NFS and NFS desires to do IO for paging purposes. In that case, the
GFP_KERNEL allocation in qib_qp.c causes a deadlock in tight memory
situations.
This fix adds support to create queue pair with GFP_NOIO flag for connected
mode only to cleanly fail the create queue pair in those situations.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Vinit Agnihotri <vinit.abhay.agnihotri@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The fix is to note the qib_mcast_qp that was found. If none is found, then
return EINVAL indicating the error.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
I don't think it makes sense for a module to have a soft dependency
on itself. This seems quite cyclic by nature and I can't see what
purpose it could serve.
OTOH libcrc32c calls crypto_alloc_shash("crc32c", 0, 0) so it pretty
much assumes that some incarnation of the "crc32c" hash algorithm has
been loaded. Therefore it makes sense to have the soft dependency
there (as crc-t10dif does.)
Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
When a TLV ioctl with numid zero is handled, the driver may spew a
kernel warning with a stack trace at each call. The check was
intended obviously only for a kernel driver, but not for a user
interaction. Let's fix it.
This reverts one hunk of
commit ef44a1ec6eee ("ALSA: sound/core: use memdup_user()"), which
replaced a number of kmalloc followed by memcpy with memdup calls.
In this case, we are copying from a struct snd_seq_port_info32 to a
struct snd_seq_port_info, but the latter is 4 bytes longer than the
32-bit version, so we need to separate kmalloc and copy calls.
Fixes: ef44a1ec6eee ('ALSA: sound/core: use memdup_user()') Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This reverts one hunk of
commit ef44a1ec6eee ("ALSA: sound/core: use memdup_user()"), which
replaced a number of kmalloc followed by memcpy with memdup calls.
In this case, we are copying from a struct snd_pcm_hw_params32 to
a struct snd_pcm_hw_params, but the latter is 4 bytes longer than
the 32-bit version, so we need to separate kmalloc and copy calls.
This actually leads to an out-of-bounds memory access later on
in sound/soc/soc-pcm.c:soc_pcm_hw_params() (detected using KASan).
Fixes: ef44a1ec6eee ('ALSA: sound/core: use memdup_user()') Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
hrtimer_cancel() waits for the completion from the callback, thus it
must not be called inside the callback itself. This was already a
problem in the past with ALSA hrtimer driver, and the early commit
[fcfdebe70759: ALSA: hrtimer - Fix lock-up] tried to address it.
However, the previous fix is still insufficient: it may still cause a
lockup when the ALSA timer instance reprograms itself in its callback.
Then it invokes the start function even in snd_timer_interrupt() that
is called in hrtimer callback itself, results in a CPU stall. This is
no hypothetical problem but actually triggered by syzkaller fuzzer.
This patch tries to fix the issue again. Now we call
hrtimer_try_to_cancel() at both start and stop functions so that it
won't fall into a deadlock, yet giving some chance to cancel the queue
if the functions have been called outside the callback. The proper
hrtimer_cancel() is called in anyway at closing, so this should be
enough.
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded. An accept(2) call on that
parent socket creates a context which then uses the tfm object.
Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.
This patch guarantees this by using locks and a reference count
on the parent socket. Any attempt to modify the parent socket will
fail with EBUSY.
Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
@console_may_schedule tracks whether console_sem was acquired through
lock or trylock. If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched(). This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.
However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines. Also, only a few drivers call
console_conditional_schedule() to begin with. This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.
If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.
Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.
Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Calvin Owens <calvinowens@fb.com> Acked-by: Jan Kara <jack@suse.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Commit 08d78658f393 ("panic: release stale console lock to always get the
logbuf printed out") introduced an unwanted bad unlock balance report when
panic() is called directly and not from OOPS (e.g. from out_of_memory()).
The difference is that in case of OOPS we disable locks debug in
oops_enter() and on direct panic call nobody does that.
Fixes: 08d78658f393 ("panic: release stale console lock to always get the logbuf printed out") Reported-by: kernel test robot <ying.huang@linux.intel.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Baoquan He <bhe@redhat.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Jan Kara <jack@suse.cz> Cc: Petr Mladek <pmladek@suse.cz> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
In some cases we may end up killing the CPU holding the console lock
while still having valuable data in logbuf. E.g. I'm observing the
following:
- A crash is happening on one CPU and console_unlock() is being called on
some other.
- console_unlock() tries to print out the buffer before releasing the lock
and on slow console it takes time.
- in the meanwhile crashing CPU does lots of printk()-s with valuable data
(which go to the logbuf) and sends IPIs to all other CPUs.
- console_unlock() finishes printing previous chunk and enables interrupts
before trying to print out the rest, the CPU catches the IPI and never
releases console lock.
This is not the only possible case: in VT/fb subsystems we have many other
console_lock()/console_unlock() users. Non-masked interrupts (or
receiving NMI in case of extreme slowness) will have the same result.
Getting the whole console buffer printed out on crash should be top
priority.
[akpm@linux-foundation.org: tweak comment text] Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Baoquan He <bhe@redhat.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
A spare array holding mem cgroup threshold events is kept around to make
sure we can always safely deregister an event and have an array to store
the new set of events in.
In the scenario where we're going from 1 to 0 registered events, the
pointer to the primary array containing 1 event is copied to the spare
slot, and then the spare slot is freed because no events are left.
However, it is freed before calling synchronize_rcu(), which means
readers may still be accessing threshold->primary after it is freed.
Fixed by only freeing after synchronize_rcu().
Signed-off-by: Martijn Coenen <maco@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
I saw the following BUG_ON triggered in a testcase where a process calls
madvise(MADV_SOFT_OFFLINE) on thps, along with a background process that
calls migratepages command repeatedly (doing ping-pong among different
NUMA nodes) for the first process:
The root cause resides in get_any_page() which retries to get a refcount
of the page to be soft-offlined. This function calls
put_hwpoison_page(), expecting that the target page is putback to LRU
list. But it can be also freed to buddy. So the second check need to
care about such case.
Fixes: af8fae7c0886 ("mm/memory-failure.c: clean up soft_offline_page()") Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
When we're using LZ4 multi compression streams for zram swap, we found
out page allocation failure message in system running test. That was
not only once, but a few(2 - 5 times per test). Also, some failure
cases were continually occurring to try allocation order 3.
In order to make parallel compression private data, we should call
kzalloc() with order 2/3 in runtime(lzo/lz4). But if there is no order
2/3 size memory to allocate in that time, page allocation fails. This
patch makes to use vmalloc() as fallback of kmalloc(), this prevents
page alloc failure warning.
After using this, we never found warning message in running test, also
It could reduce process startup latency about 60-120ms in each case.
We can end up allocating a new compression stream with GFP_KERNEL from
within the IO path, which may result is nested (recursive) IO
operations. That can introduce problems if the IO path in question is a
reclaimer, holding some locks that will deadlock nested IOs.
Allocate streams and working memory using GFP_NOIO flag, forbidding
recursive IO and FS operations.
An example:
inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
git/20158 [HC0[0]:SC0[0]:HE1:SE1] takes:
(jbd2_handle){+.+.?.}, at: start_this_handle+0x4ca/0x555
{IN-RECLAIM_FS-W} state was registered at:
__lock_acquire+0x8da/0x117b
lock_acquire+0x10c/0x1a7
start_this_handle+0x52d/0x555
jbd2__journal_start+0xb4/0x237
__ext4_journal_start_sb+0x108/0x17e
ext4_dirty_inode+0x32/0x61
__mark_inode_dirty+0x16b/0x60c
iput+0x11e/0x274
__dentry_kill+0x148/0x1b8
shrink_dentry_list+0x274/0x44a
prune_dcache_sb+0x4a/0x55
super_cache_scan+0xfc/0x176
shrink_slab.part.14.constprop.25+0x2a2/0x4d3
shrink_zone+0x74/0x140
kswapd+0x6b7/0x930
kthread+0x107/0x10f
ret_from_fork+0x3f/0x70
irq event stamp: 138297
hardirqs last enabled at (138297): debug_check_no_locks_freed+0x113/0x12f
hardirqs last disabled at (138296): debug_check_no_locks_freed+0x33/0x12f
softirqs last enabled at (137818): __do_softirq+0x2d3/0x3e9
softirqs last disabled at (137813): irq_exit+0x41/0x95
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(jbd2_handle);
<Interrupt>
lock(jbd2_handle);
A slave timer instance might be still accessible in a racy way while
operating the master instance as it lacks of locking. Since the
master operation is mostly protected with timer->lock, we should cope
with it while changing the slave instance, too. Also, some linked
lists (active_list and ack_list) of slave instances aren't unlinked
immediately at stopping or closing, and this may lead to unexpected
accesses.
This patch tries to address these issues. It adds spin lock of
timer->lock (either from master or slave, which is equivalent) in a
few places. For avoiding a deadlock, we ensure that the global
slave_active_lock is always locked at first before each timer lock.
Also, ack and active_list of slave instances are properly unlinked at
snd_timer_stop() and snd_timer_close().
Last but not least, remove the superfluous call of _snd_timer_stop()
at removing slave links. This is a noop, and calling it may confuse
readers wrt locking. Further cleanup will follow in a later patch.
Actually we've got reports of use-after-free by syzkaller fuzzer, and
this hopefully fixes these issues.
We have found that migration source will trigger a BUG that the refcount
of mle is already zero before put when the target is down during
migration. The situation is as follows:
dlm_migrate_lockres
dlm_add_migration_mle
dlm_mark_lockres_migrating
dlm_get_mle_inuse
<<<<<< Now the refcount of the mle is 2.
dlm_send_one_lockres and wait for the target to become the
new master.
<<<<<< o2hb detect the target down and clean the migration
mle. Now the refcount is 1.
dlm_migrate_lockres woken, and put the mle twice when found the target
goes down which trigger the BUG with the following message:
"ERROR: bad mle: ".
Signed-off-by: Jiufei Xue <xuejiufei@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
/*
* Usage guidelines:
* _text, _data: architecture specific, don't use them in
* arch-independent code
* [_stext, _etext]: contains .text.* sections, may also contain
* .rodata.*
* and/or .init.* sections
_text is not guaranteed across architectures. Architectures such as ARM
may reuse parts which are not actually text and erroneously trigger a bug.
Switch to using _stext which is guaranteed to contain text sections.
Came out of https://lkml.kernel.org/g/<567B1176.4000106@redhat.com>
Signed-off-by: Laura Abbott <labbott@fedoraproject.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
In some cases tmp_bug can be not filled in cifs_filldir and stay uninitialized,
therefore its printk with "%s" modifier can leak content of kernelspace memory.
If old content of this buffer does not contain '\0' access bejond end of
allocated object can crash the host.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Steve French <sfrench@localhost.localdomain> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
cifs_call_async() queues the MID to the pending list and calls
smb_send_rqst(). If smb_send_rqst() performs a partial send, it sets
the tcpStatus to CifsNeedReconnect and returns an error code to
cifs_call_async(). In this case, cifs_call_async() removes the MID
from the list and returns to the caller.
However, cifs_call_async() releases the server mutex _before_ removing
the MID. This means that a cifs_reconnect() can race with this function
and manage to remove the MID from the list and delete the entry before
cifs_call_async() calls cifs_delete_mid(). This leads to various
crashes due to the use after free in cifs_delete_mid().
Fix this by removing the MID in cifs_call_async() before releasing the
srv_mutex. Also hold the srv_mutex in cifs_reconnect() until the MIDs
are moved out of the pending list.
Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@localhost.localdomain>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
The value returned by sys_personality has type "long int".
It is saved to a variable of type "int", which is not a problem
yet because the type of task_struct->pesonality is "unsigned int".
The problem is the sign extension from "int" to "long int"
that happens on return from sys_sparc64_personality.
For example, a userspace call personality((unsigned) -EINVAL) will
result to any subsequent personality call, including absolutely
harmless read-only personality(0xffffffff) call, failing with
errno set to EINVAL.
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
ALSA timer ioctls have an open race and this may lead to a
use-after-free of timer instance object. A simplistic fix is to make
each ioctl exclusive. We have already tread_sem for controlling the
tread, and extend this as a global mutex to be applied to each ioctl.
The downside is, of course, the worse concurrency. But these ioctls
aren't to be parallel accessible, in anyway, so it should be fine to
serialize there.
commit 4956e10903fd ("ARM: 6244/1: mmci: add variant data and default
MCICLOCK support") added variant data for ARM, U300 and Ux500 variants.
The Nomadik NHK8815/8820 variant was erroneously labeled as a U300
variant, and when the proper Nomadik variant was later introduced in
commit 34fd421349ff ("ARM: 7378/1: mmci: add support for the Nomadik MMCI
variant") this was not fixes. Let's say this fixes the latter commit as
there was no proper Nomadik support until then.
Fixes: 34fd421349ff ("ARM: 7378/1: mmci: add support for the Nomadik...") Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Cyclic transfer callbacks rely on block completion interrupts which were
disabled in commit ff7b05f29fd4 ("dmaengine/dw_dmac: Don't handle block
interrupts"). This re-enables block interrupts so the cyclic callbacks
can work. Other transfer types are not affected as they set the INT_EN
bit only on the last block.
Commit 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and
chan_cfg register on resume") moved some channel initialisation to
a new function which must be called before starting a transfer.
This updates dw_dma_cyclic_start() to use dwc_dostart() like the other
modes, thus ensuring dwc_initialize() gets called and removing some code
duplication.
Fixes: 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume") Signed-off-by: Mans Rullgard <mans@mansr.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
ALSA timer instance object has a couple of linked lists and they are
unlinked unconditionally at snd_timer_stop(). Meanwhile
snd_timer_interrupt() unlinks it, but it calls list_del() which leaves
the element list itself unchanged. This ends up with unlinking twice,
and it was caught by syzkaller fuzzer.
The fix is to use list_del_init() variant properly there, too.
GCC 6 will include changes to generated code with -mcmodel=large,
which is used to build kernel modules on powerpc64le. This was
necessary because the large model is supposed to allow arbitrary
sizes and locations of the code and data sections, but the ELFv2
global entry point prolog still made the unconditional assumption
that the TOC associated with any particular function can be found
within 2 GB of the function entry point:
The new .reloc triggers an optimization in the linker that will
replace this new prolog with the original code (see above) if the
linker determines that the distance between .TOC. and func is in
range after all.
Since this new relocation is now present in module object files,
the kernel module loader is required to handle them too. This
patch adds support for the new relocation and implements the
same optimization done by the GNU linker.
Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
If a text section starts out with a data blob before the first
function start label, disassembly parsing doing in recordmcount.pl
gets confused on powerpc, leading to creation of corrupted module
objects.
This was not a problem so far since the compiler would never create
such text sections. However, this has changed with a recent change
in GCC 6 to support distances of > 2GB between a function and its
assoicated TOC in the ELFv2 ABI, exposing this problem.
There is already code in recordmcount.pl to handle such data blobs
on the sparc64 platform. This patch uses the same method to handle
those on powerpc as well.
Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
On a 64bit kernel build the compiler aligns the _sifields union in the
struct siginfo_t on a 64bit address. The __ARCH_SI_PREAMBLE_SIZE define
compensates for this alignment and thus fixes the wait testcase of the
strace package.
The symptoms of a wrong __ARCH_SI_PREAMBLE_SIZE value is that
_sigchld.si_stime variable is missed to be copied and thus after a
copy_siginfo() will have uninitialized values.
Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
In balloon_page_dequeue, pages_lock should cover the loop
(ie, list_for_each_entry_safe). Otherwise, the cursor page could
be isolated by compaction and then list_del by isolation could
poison the page->lru.{prev,next} so the loop finally could
access wrong address like this. This patch fixes the bug.
Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.com>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
During my compaction-related stuff, I encountered a bug
with ballooning.
With repeated inflating and deflating cycle, guest memory(
ie, cat /proc/meminfo | grep MemTotal) is decreased and
couldn't be recovered.
The reason is balloon_lock doesn't cover release_pages_balloon
so struct virtio_balloon fields could be overwritten by race
of fill_balloon(e,g, vb->*pfns could be critical).
This patch fixes it in my test.
Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
ALSA sequencer code has an open race between the timer setup ioctl and
the close of the client. This was triggered by syzkaller fuzzer, and
a use-after-free was caught there as a result.
This patch papers over it by adding a proper queue->timer_mutex lock
around the timer-related calls in the relevant code path.
snd_seq_ioctl_remove_events() calls snd_seq_fifo_clear()
unconditionally even if there is no FIFO assigned, and this leads to
an Oops due to NULL dereference. The fix is just to add a proper NULL
check.
projects / thirdparty / kernel / stable.git / log
