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commit 95a793c3bc75cf888e0e641d656e7d080f487d8b upstream.
When processing request to add/replace user-defined element set, check
of given element identifier and decision of numeric identifier is done
in "__snd_ctl_add_replace()" helper function. When the result of check
is wrong, the helper function returns error code. The error code shall
be returned to userspace application.
Current implementation includes bug to return zero to userspace application
regardless of the result. This commit fixes the bug.
Cc: <stable@vger.kernel.org>
Fixes: e1a7bfe38079 ("ALSA: control: Fix race between adding and removing a user element")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20201113092043.16148-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Guenter reports a build failure on cell_defconfig and maple_defconfg:
In file included from arch/powerpc/include/asm/kup.h:10:0,
from arch/powerpc/include/asm/uaccess.h:12,
from arch/powerpc/lib/checksum_wrappers.c:24:
arch/powerpc/include/asm/book3s/64/kup-radix.h:5:1: error: data definition has no type or storage class [-Werror]
DECLARE_STATIC_KEY_FALSE(uaccess_flush_key);
^~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/book3s/64/kup-radix.h:5:1: error: type defaults to ‘int’ in declaration of ‘DECLARE_STATIC_KEY_FALSE’ [-Werror=implicit-int]
arch/powerpc/include/asm/book3s/64/kup-radix.h:5:1: error: parameter names (without types) in function declaration [-Werror]
arch/powerpc/include/asm/book3s/64/kup-radix.h: In function ‘prevent_user_access’:
arch/powerpc/include/asm/book3s/64/kup-radix.h:18:6: error: implicit declaration of function ‘static_branch_unlikely’ [-Werror=implicit-function-declaration]
if (static_branch_unlikely(&uaccess_flush_key))
^~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/book3s/64/kup-radix.h:18:30: error: ‘uaccess_flush_key’ undeclared (first use in this function); did you mean
‘do_uaccess_flush’?
if (static_branch_unlikely(&uaccess_flush_key))
^~~~~~~~~~~~~~~~~
do_uaccess_flush
arch/powerpc/include/asm/book3s/64/kup-radix.h:18:30: note: each undeclared identifier is reported only once for each function it appears in
cc1: all warnings being treated as errors
This is because I failed to include linux/jump_label.h in kup-radix.h. Include it.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 488dac0c9237647e9b8f788b6a342595bfa40bda ]
The attr->set() receive a value of u64, but simple_strtoll() is used for
doing the conversion. It will lead to the error cast if user inputs a
negative value.
Use kstrtoull() instead of simple_strtoll() to convert a string got from
the user to an unsigned value. The former will return '-EINVAL' if it
gets a negetive value, but the latter can't handle the situation
correctly. Make 'val' unsigned long long as what kstrtoull() takes,
this will eliminate the compile warning on no 64-bit architectures.
Fixes: f7b88631a897 ("fs/libfs.c: fix simple_attr_write() on 32bit machines")
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/1605341356-11872-1-git-send-email-yangyicong@hisilicon.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit eb8409071a1d47e3593cfe077107ac46853182ab ]
This reverts commit 6ff646b2ceb0eec916101877f38da0b73e3a5b7f.
Your maintainer committed a major braino in the rmap code by adding the
attr fork, bmbt, and unwritten extent usage bits into rmap record key
comparisons. While XFS uses the usage bits *in the rmap records* for
cross-referencing metadata in xfs_scrub and xfs_repair, it only needs
the owner and offset information to distinguish between reverse mappings
of the same physical extent into the data fork of a file at multiple
offsets. The other bits are not important for key comparisons for index
lookups, and never have been.
Eric Sandeen reports that this causes regressions in generic/299, so
undo this patch before it does more damage.
Reported-by: Eric Sandeen <sandeen@sandeen.net>
Fixes: 6ff646b2ceb0 ("xfs: fix rmap key and record comparison functions")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2ba546ebe0ce2af47833d8912ced9b4a579f13cb ]
At the start of driver initialization, we do not know what bias
setting the bootloader has configured the system for and we only know
for certain the very first time we do a transition.
However, since the initial value of the comparison index is -EINVAL,
this negative value results in an array out of bound access on the
very first transition.
Since we don't know what the setting is, we just set the bias
configuration as there is nothing to compare against. This prevents
the array out of bound access.
NOTE: Even though we could use a more relaxed check of "< 0" the only
valid values(ignoring cosmic ray induced bitflips) are -EINVAL, 0+.
Fixes: 40b1936efebd ("regulator: Introduce TI Adaptive Body Bias(ABB) on-chip LDO driver")
Link: https://lore.kernel.org/linux-mm/CA+G9fYuk4imvhyCN7D7T6PMDH6oNp6HDCRiTUKMQ6QXXjBa4ag@mail.gmail.com/
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20201118145009.10492-1-nm@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ac3b57adf87ad9bac7e33ca26bbbb13fae1ed62b ]
If the clk_register fails, we should free h before
function returns to prevent memleak.
Fixes: 474402291a0ad ("MIPS: Alchemy: clock framework integration of onchip clocks")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cd0d83eab2e0c26fe87a10debfedbb23901853c1 ]
m_can_handle_state_change() is called with the new_state as an argument.
In the switch statements for CAN_STATE_ERROR_ACTIVE, the comment and the
following code indicate that a CAN_STATE_ERROR_WARNING is handled.
This patch fixes this problem by changing the case to CAN_STATE_ERROR_WARNING.
Signed-off-by: Wu Bo <wubo.oduw@gmail.com>
Link: http://lore.kernel.org/r/20200129022330.21248-2-wubo.oduw@gmail.com
Cc: Dan Murphy <dmurphy@ti.com>
Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8a68cc0d690c9e5730d676b764c6f059343b842c ]
The left shift of int 32 bit integer constant 1 is evaluated using 32 bit
arithmetic and then assigned to a signed 64 bit variable. In the case where
time_ref->adapter->ts_used_bits is 32 or more this can lead to an oveflow.
Avoid this by shifting using the BIT_ULL macro instead.
Fixes: bb4785551f64 ("can: usb: PEAK-System Technik USB adapters driver core")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20201105112427.40688-1-colin.king@canonical.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a1e654070a60d5d4f7cce59c38f4ca790bb79121 ]
netif_rx() is meant to be called from interrupt contexts. can_restart() may be
called by can_restart_work(), which is called from a worqueue, so it may run in
process context. Use netif_rx_ni() instead.
Fixes: 39549eef3587 ("can: CAN Network device driver and Netlink interface")
Co-developed-by: Loris Fauster <loris.fauster@ttcontrol.com>
Signed-off-by: Loris Fauster <loris.fauster@ttcontrol.com>
Signed-off-by: Alejandro Concepcion Rodriguez <alejandro@acoro.eu>
Link: https://lore.kernel.org/r/4e84162b-fb31-3a73-fa9a-9438b4bd5234@acoro.eu
[mkl: use netif_rx_ni() instead of netif_rx_any_context()]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b0e5a05cc9e37763c7f19366d94b1a6160c755bc ]
When execute command "perf lock report", it hits failure and outputs log
as follows:
perf: builtin-lock.c:623: report_lock_release_event: Assertion `!(seq->read_count < 0)' failed.
Aborted
This is an imbalance issue. The locking sequence structure
"lock_seq_stat" contains the reader counter and it is used to check if
the locking sequence is balance or not between acquiring and releasing.
If the tool wrongly frees "lock_seq_stat" when "read_count" isn't zero,
the "read_count" will be reset to zero when allocate a new structure at
the next time; thus it causes the wrong counting for reader and finally
results in imbalance issue.
To fix this issue, if detects "read_count" is not zero (means still have
read user in the locking sequence), goto the "end" tag to skip freeing
structure "lock_seq_stat".
Fixes: e4cef1f65061 ("perf lock: Fix state machine to recognize lock sequence")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201104094229.17509-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 33d0d843872c5ddbe28457a92fc6f2487315fb9f ]
The SPI chip selects are represented as:
cs-gpios = <&gpio4 11 GPIO_ACTIVE_LOW>, <&gpio4 13 GPIO_ACTIVE_LOW>;
, which means that they are used in GPIO function instead of native
SPI mode.
Fix the IOMUX for the chip select 1 to use GPIO4_13 instead of
the native CSPI_SSI function.
Fixes: c605cbf5e135 ("ARM: dts: imx: add device tree support for Freescale imx50evk board")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 31b4d8e172f614adc53ddecb4b6b2f6411a49b84 ]
MIPS should export its local version of "has_transparent_hugepage"
so that loadable modules (dax) can use it.
Fixes this build error:
ERROR: modpost: "has_transparent_hugepage" [drivers/dax/dax.ko] undefined!
Fixes: fd8cfd300019 ("arch: fix has_transparent_hugepage()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@vger.kernel.org
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: linux-nvdimm@lists.01.org
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 33b6c39e747c552fa770eecebd1776f1f4a222b1 ]
The "revid" is used to store negative error codes so it should be an int
type.
Fixes: e27c729219ad ("Input: add driver for ADXL345/346 Digital Accelerometers")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Link: https://lore.kernel.org/r/20201026072824.GA1620546@mwanda
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 22843291efc986ce7722610073fcf85a39b4cb13 ]
__sb_start_write has some weird looking lockdep code that claims to
exist to handle nested freeze locking requests from xfs. The code as
written seems broken -- if we think we hold a read lock on any of the
higher freeze levels (e.g. we hold SB_FREEZE_WRITE and are trying to
lock SB_FREEZE_PAGEFAULT), it converts a blocking lock attempt into a
trylock.
However, it's not correct to downgrade a blocking lock attempt to a
trylock unless the downgrading code or the callers are prepared to deal
with that situation. Neither __sb_start_write nor its callers handle
this at all. For example:
sb_start_pagefault ignores the return value completely, with the result
that if xfs_filemap_fault loses a race with a different thread trying to
fsfreeze, it will proceed without pagefault freeze protection (thereby
breaking locking rules) and then unlocks the pagefault freeze lock that
it doesn't own on its way out (thereby corrupting the lock state), which
leads to a system hang shortly afterwards.
Normally, this won't happen because our ownership of a read lock on a
higher freeze protection level blocks fsfreeze from grabbing a write
lock on that higher level. *However*, if lockdep is offline,
lock_is_held_type unconditionally returns 1, which means that
percpu_rwsem_is_held returns 1, which means that __sb_start_write
unconditionally converts blocking freeze lock attempts into trylocks,
even when we *don't* hold anything that would block a fsfreeze.
Apparently this all held together until 5.10-rc1, when bugs in lockdep
caused lockdep to shut itself off early in an fstests run, and once
fstests gets to the "race writes with freezer" tests, kaboom. This
might explain the long trail of vanishingly infrequent livelocks in
fstests after lockdep goes offline that I've never been able to
diagnose.
We could fix it by spinning on the trylock if wait==true, but AFAICT the
locking works fine if lockdep is not built at all (and I didn't see any
complaints running fstests overnight), so remove this snippet entirely.
NOTE: Commit f4b554af9931 in 2015 created the current weird logic (which
used to exist in a different form in commit 5accdf82ba25c from 2012) in
__sb_start_write. XFS solved this whole problem in the late 2.6 era by
creating a variant of transactions (XFS_TRANS_NO_WRITECOUNT) that don't
grab intwrite freeze protection, thus making lockdep's solution
unnecessary. The commit claims that Dave Chinner explained that the
trylock hack + comment could be removed, but nobody ever did.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 891deb87585017d526b67b59c15d38755b900fea ]
cpu_psci_cpu_die() is called in the context of the dying CPU, which
will no longer be online or tracked by RCU. It is therefore not generally
safe to call printk() if the PSCI "cpu off" request fails, so remove the
pr_crit() invocation.
Cc: Qian Cai <cai@redhat.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201106103602.9849-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 63fbf8013b2f6430754526ef9594f229c7219b1f ]
There need to enable pclk_gpio when do irq_create_mapping, since it will
do access to gpio controller.
Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Kever Yang<kever.yang@rock-chips.com>
Link: https://lore.kernel.org/r/20201013063731.3618-3-jay.xu@rock-chips.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1f492eab67bced119a0ac7db75ef2047e29a30c6 ]
The driver sends Ethernet Management Datagram (EMAD) packets to the
device for configuration purposes and waits for up to 200ms for a reply.
A request is retried up to 5 times.
When the system is under heavy load, replies are not always processed in
time and EMAD transactions fail.
Make the process more robust to such delays by using exponential
backoff. First wait for up to 200ms, then retransmit and wait for up to
400ms and so on.
Fixes: caf7297e7ab5 ("mlxsw: core: Introduce support for asynchronous EMAD register access")
Reported-by: Denis Yulevich <denisyu@nvidia.com>
Tested-by: Denis Yulevich <denisyu@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3d5179458d22dc0b4fdc724e4bed4231a655112a ]
When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))
in net/core/dev.c due to still having the NC-SI packet handler
registered.
# echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind
------------[ cut here ]------------
kernel BUG at net/core/dev.c:10254!
Internal error: Oops - BUG: 0 [#1] SMP ARM
CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 #46
Hardware name: Generic DT based system
PC is at netdev_run_todo+0x314/0x394
LR is at cpumask_next+0x20/0x24
pc : [<806f5830>] lr : [<80863cb0>] psr: 80000153
sp : 855bbd58 ip : 00000001 fp : 855bbdac
r10: 80c03d00 r9 : 80c06228 r8 : 81158c54
r7 : 00000000 r6 : 80c05dec r5 : 80c05d18 r4 : 813b9280
r3 : 813b9054 r2 : 8122c470 r1 : 00000002 r0 : 00000002
Flags: Nzcv IRQs on FIQs off Mode SVC_32 ISA ARM Segment none
Control: 00c5387d Table: 85514008 DAC: 00000051
Process sh (pid: 115, stack limit = 0x7cb5703d)
...
Backtrace:
[<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)
r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410
r4:813b9000
[<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)
[<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)
r5:8115b410 r4:813b9000
[<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)
Fixes: bd466c3fb5a4 ("net/faraday: Support NCSI mode")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20201117024448.1170761-1-joel@jms.id.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1b9e2a8c99a5c021041bfb2d512dc3ed92a94ffd ]
During loss recovery, retransmitted packets are forced to use TCP
timestamps to calculate the RTT samples, which have a millisecond
granularity. BBR is designed using a microsecond granularity. As a
result, multiple RTT samples could be truncated to the same RTT value
during loss recovery. This is problematic, as BBR will not enter
PROBE_RTT if the RTT sample is <= the current min_rtt sample, meaning
that if there are persistent losses, PROBE_RTT will constantly be
pushed off and potentially never re-entered. This patch makes sure
that BBR enters PROBE_RTT by checking if RTT sample is < the current
min_rtt sample, rather than <=.
The Netflix transport/TCP team discovered this bug in the Linux TCP
BBR code during lab tests.
Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control")
Signed-off-by: Ryan Sharpelletti <sharpelletti@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Link: https://lore.kernel.org/r/20201116174412.1433277-1-sharpelletti.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 057a10fa1f73d745c8e69aa54ab147715f5630ae ]
A call trace was found in Hangbin's Codenomicon testing with debug kernel:
[ 2615.981988] ODEBUG: free active (active state 0) object type: timer_list hint: sctp_generate_proto_unreach_event+0x0/0x3a0 [sctp]
[ 2615.995050] WARNING: CPU: 17 PID: 0 at lib/debugobjects.c:328 debug_print_object+0x199/0x2b0
[ 2616.095934] RIP: 0010:debug_print_object+0x199/0x2b0
[ 2616.191533] Call Trace:
[ 2616.194265] <IRQ>
[ 2616.202068] debug_check_no_obj_freed+0x25e/0x3f0
[ 2616.207336] slab_free_freelist_hook+0xeb/0x140
[ 2616.220971] kfree+0xd6/0x2c0
[ 2616.224293] rcu_do_batch+0x3bd/0xc70
[ 2616.243096] rcu_core+0x8b9/0xd00
[ 2616.256065] __do_softirq+0x23d/0xacd
[ 2616.260166] irq_exit+0x236/0x2a0
[ 2616.263879] smp_apic_timer_interrupt+0x18d/0x620
[ 2616.269138] apic_timer_interrupt+0xf/0x20
[ 2616.273711] </IRQ>
This is because it holds asoc when transport->proto_unreach_timer starts
and puts asoc when the timer stops, and without holding transport the
transport could be freed when the timer is still running.
So fix it by holding/putting transport instead for proto_unreach_timer
in transport, just like other timers in transport.
v1->v2:
- Also use sctp_transport_put() for the "out_unlock:" path in
sctp_generate_proto_unreach_event(), as Marcelo noticed.
Fixes: 50b5d6ad6382 ("sctp: Fix a race between ICMP protocol unreachable and connect()")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/102788809b554958b13b95d33440f5448113b8d6.1605331373.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3beb9be165083c2964eba1923601c3bfac0b02d4 ]
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: 3ced0a88cd4c ("qlcnic: Add support to run firmware POST")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Link: https://lore.kernel.org/r/1605248186-16013-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4ee18c179e5e815fa5575e0d2db0c05795a804ee ]
The x25_disconnect function in x25_subr.c would decrease the refcount of
"x25->neighbour" (struct x25_neigh) and reset this pointer to NULL.
However, the x25_rx_call_request function in af_x25.c, which is called
when we receive a connection request, does not increase the refcount when
it assigns the pointer.
Fix this issue by increasing the refcount of "struct x25_neigh" in
x25_rx_call_request.
This patch fixes frequent kernel crashes when using AF_X25 sockets.
Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Link: https://lore.kernel.org/r/20201112103506.5875-1-xie.he.0141@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6d9c8d15af0ef20a66a0b432cac0d08319920602 ]
Slave function read the following capabilities from the wrong offset:
1. log_mc_entry_sz
2. fs_log_entry_sz
3. log_mc_hash_sz
Fix that by adjusting these capabilities offset to match firmware
layout.
Due to the wrong offset read, the following issues might occur:
1+2. Negative value reported at max_mcast_qp_attach.
3. Driver to init FW with multicast hash size of zero.
Fixes: a40ded604365 ("net/mlx4_core: Add masking for a few queries on HCA caps")
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Eran Ben Elisha <eranbe@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20201118081922.553-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1ba86d4366e023d96df3dbe415eea7f1dc08c303 ]
Static checking revealed that a previous fix to
netlbl_unlabel_staticlist() leaves a stack variable uninitialized,
this patches fixes that.
Fixes: 866358ec331f ("netlabel: fix our progress tracking in netlbl_unlabel_staticlist()")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/r/160530304068.15651.18355773009751195447.stgit@sifl
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 866358ec331f8faa394995fb4b511af1db0247c8 ]
The current NetLabel code doesn't correctly keep track of the netlink
dump state in some cases, in particular when multiple interfaces with
large configurations are loaded. The problem manifests itself by not
reporting the full configuration to userspace, even though it is
loaded and active in the kernel. This patch fixes this by ensuring
that the dump state is properly reset when necessary inside the
netlbl_unlabel_staticlist() function.
Fixes: 8cc44579d1bd ("NetLabel: Introduce static network labels for unlabeled connections")
Signed-off-by: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/r/160484450633.3752.16512718263560813473.stgit@sifl
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1532b9778478577152201adbafa7738b1e844868 ]
DSA network devices rely on having their DSA management interface up and
running otherwise their ndo_open() will return -ENETDOWN. Without doing
this it would not be possible to use DSA devices as netconsole when
configured on the command line. These devices also do not utilize the
upper/lower linking so the check about the netpoll device having upper
is not going to be a problem.
The solution adopted here is identical to the one done for
net/ipv4/ipconfig.c with 728c02089a0e ("net: ipv4: handle DSA enabled
master network devices"), with the network namespace scope being
restricted to that of the process configuring netpoll.
Fixes: 04ff53f96a93 ("net: dsa: Add netconsole support")
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20201117035236.22658-1-f.fainelli@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7a30ecc9237681bb125cbd30eee92bef7e86293d ]
In br_forward.c and br_input.c fields dev->stats.tx_dropped and
dev->stats.multicast are populated, but they are ignored in
ndo_get_stats64.
Fixes: 28172739f0a2 ("net: fix 64 bit counters on 32 bit arches")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/58ea9963-77ad-a7cf-8dfd-fc95ab95f606@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7b027c249da54f492699c43e26cba486cfd48035 ]
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: 39a6f4bce6b4 ("b44: replace the ssb_dma API with the generic DMA API")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/1605582131-36735-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e33de7c5317e2827b2ba6fd120a505e9eb727b05 ]
nlmsg_cancel() needs to be called in the error path of
inet_req_diag_fill to cancel the message.
Fixes: d545caca827b ("net: inet: diag: expose the socket mark to privileged processes.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20201116082018.16496-1-wanghai38@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 849920c703392957f94023f77ec89ca6cf119d43 ]
If sb_occ_port_pool_get() failed in devlink_nl_sb_port_pool_fill(),
msg should be canceled by genlmsg_cancel().
Fixes: df38dafd2559 ("devlink: implement shared buffer occupancy monitoring interface")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20201113111622.11040-1-wanghai38@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4260330b32b14330cfe427d568ac5f5b29b5be3d ]
The module eeprom address range returned by bnxt_get_module_eeprom()
should be 256 bytes of A0h address space, the lower half of the A2h
address space, and page 0 for the upper half of the A2h address space.
Fix the firmware call by passing page_number 0 for the A2h slave address
space.
Fixes: 42ee18fe4ca2 ("bnxt_en: Add Support for ETHTOOL_GMODULEINFO and ETHTOOL_GMODULEEEPRO")
Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6dceaa9f56e22d0f9b4c4ad2ed9e04e315ce7fe5 ]
The `skb' is mapped for DMA in ns_send() but does not unmap DMA in case
push_scqe() fails to submit the `skb'. The memory of the `skb' is
released so only the DMA mapping is leaking.
Unmap the DMA mapping in case push_scqe() failed.
Fixes: 864a3ff635fa7 ("atm: [nicstar] remove virt_to_bus() and support 64-bit platforms")
Cc: Chas Williams <3chas3@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a5ebcbdf34b65fcc07f38eaf2d60563b42619a59 ]
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Link: https://lore.kernel.org/r/1605581105-35295-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9debfb81e7654fe7388a49f45bc4d789b94c1103 upstream.
Clang is more aggressive about -Wformat warnings when the format flag
specifies a type smaller than the parameter. It turns out that gsi is an
int. Fixes:
drivers/acpi/evged.c:105:48: warning: format specifies type 'unsigned
char' but the argument has type 'unsigned int' [-Wformat]
trigger == ACPI_EDGE_SENSITIVE ? 'E' : 'L', gsi);
^~~
Link: https://github.com/ClangBuiltLinux/linux/issues/378
Fixes: ea6f3af4c5e6 ("ACPI: GED: add support for _Exx / _Lxx handler methods")
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dcd479e10a0510522a5d88b29b8f79ea3467d501 upstream.
When (for example) an IBSS station is pre-moved to AUTHORIZED
before it's inserted, and then the insertion fails, we don't
clean up the fast RX/TX states that might already have been
created, since we don't go through all the state transitions
again on the way down.
Do that, if it hasn't been done already, when the station is
freed. I considered only freeing the fast TX/RX state there,
but we might add more state so it's more robust to wind down
the state properly.
Note that we warn if the station was ever inserted, it should
have been properly cleaned up in that case, and the driver
will probably not like things happening out of order.
Reported-by: syzbot+2e293dbd67de2836ba42@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20201009141710.7223b322a955.I95bd08b9ad0e039c034927cce0b75beea38e059b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77e70d351db7de07a46ac49b87a6c3c7a60fca7e upstream.
We need to make sure we cancel the reinit work before we tear down the
driver structures.
Reported-by: Bodong Zhao <nopitydays@gmail.com>
Tested-by: Bodong Zhao <nopitydays@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29daf869cbab69088fe1755d9dd224e99ba78b56 upstream.
The kernel expects pte_young() to work regardless of CONFIG_SWAP.
Make sure a minor fault is taken to set _PAGE_ACCESSED when it
is not already set, regardless of the selection of CONFIG_SWAP.
This adds at least 3 instructions to the TLB miss exception
handlers fast path. Following patch will reduce this overhead.
Also update the rotation instruction to the correct number of bits
to reflect all changes done to _PAGE_ACCESSED over time.
Fixes: d069cb4373fe ("powerpc/8xx: Don't touch ACCESSED when no SWAP.")
Fixes: 5f356497c384 ("powerpc/8xx: remove unused _PAGE_WRITETHRU")
Fixes: e0a8e0d90a9f ("powerpc/8xx: Handle PAGE_USER via APG bits")
Fixes: 5b2753fc3e8a ("powerpc/8xx: Implementation of PAGE_EXEC")
Fixes: a891c43b97d3 ("powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/af834e8a0f1fa97bfae65664950f0984a70c4750.1602492856.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbe4d69d252e9e65c6c46826980b77b11a142065 upstream.
The spec for the pca9546 was missing. This chip is the same as the pca9545
except that it lacks interrupt lines. While the i2c_device_id table mapped
the pca9546 to the pca9545 definition the compatible table did not.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Peter Rosin <peda@axentia.se>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e50e4f0b85be308a01b830c5fbdffc657e1a6dd0 upstream
If interrupt comes late, during probe error path or device remove (could
be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler
i2c_imx_isr() will access registers with the clock being disabled. This
leads to external abort on non-linefetch on Toradex Colibri VF50 module
(with Vybrid VF5xx):
Unhandled fault: external abort on non-linefetch (0x1008) at 0x8882d003
Internal error: : 1008 [#1] ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 5.7.0 #607
Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
(i2c_imx_isr) from [<8017009c>] (free_irq+0x25c/0x3b0)
(free_irq) from [<805844ec>] (release_nodes+0x178/0x284)
(release_nodes) from [<80580030>] (really_probe+0x10c/0x348)
(really_probe) from [<80580380>] (driver_probe_device+0x60/0x170)
(driver_probe_device) from [<80580630>] (device_driver_attach+0x58/0x60)
(device_driver_attach) from [<805806bc>] (__driver_attach+0x84/0xc0)
(__driver_attach) from [<8057e228>] (bus_for_each_dev+0x68/0xb4)
(bus_for_each_dev) from [<8057f3ec>] (bus_add_driver+0x144/0x1ec)
(bus_add_driver) from [<80581320>] (driver_register+0x78/0x110)
(driver_register) from [<8010213c>] (do_one_initcall+0xa8/0x2f4)
(do_one_initcall) from [<80c0100c>] (kernel_init_freeable+0x178/0x1dc)
(kernel_init_freeable) from [<80807048>] (kernel_init+0x8/0x110)
(kernel_init) from [<80100114>] (ret_from_fork+0x14/0x20)
Additionally, the i2c_imx_isr() could wake up the wait queue
(imx_i2c_struct->queue) before its initialization happens.
The resource-managed framework should not be used for interrupt handling,
because the resource will be released too late - after disabling clocks.
The interrupt handler is not prepared for such case.
Fixes: 1c4b6c3bcf30 ("i2c: imx: implement bus recovery")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 90ad2cbe88c22d0215225ab9594eeead0eb24fde upstream
Instead of repeatedly calling clk_get_rate for each transfer, register
a clock notifier to update the cached divider value each time the clock
rate actually changes.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream.
IBM Power9 processors can speculatively operate on data in the L1 cache before
it has been completely validated, via a way-prediction mechanism. It is not possible
for an attacker to determine the contents of impermissible memory using this method,
since these systems implement a combination of hardware and software security measures
to prevent scenarios where protected data could be leaked.
However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that the
attacker controls. This can be used for example to speculatively bypass "kernel
user access prevention" techniques, as discovered by Anthony Steinhauser of
Google's Safeside Project. This is not an attack by itself, but there is a possibility
it could be used in conjunction with side-channels or other weaknesses in the
privileged code to construct an attack.
This issue can be mitigated by flushing the L1 cache between privilege boundaries
of concern. This patch flushes the L1 cache after user accesses.
This is part of the fix for CVE-2020-4788.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d02f6b7dab8228487268298ea1f21081c0b4b3eb upstream.
get/put_user() can be called with nontrivial arguments. fs/proc/page.c
has a good example:
if (put_user(stable_page_flags(ppage), out)) {
stable_page_flags() is quite a lot of code, including spin locks in
the page allocator.
Ensure these arguments are evaluated before user access is allowed.
This improves security by reducing code with access to userspace, but
it also fixes a PREEMPT bug with KUAP on powerpc/64s:
stable_page_flags() is currently called with AMR set to allow writes,
it ends up calling spin_unlock(), which can call preempt_schedule. But
the task switch code can not be called with AMR set (it relies on
interrupts saving the register), so this blows up.
It's fine if the code inside allow_user_access() is preemptible,
because a timer or IPI will save the AMR, but it's not okay to
explicitly cause a reschedule.
Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200407041245.600651-1-npiggin@gmail.com
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 61e3acd8c693a14fc69b824cb5b08d02cb90a6e7 upstream.
The KUAP implementation adds calls in clear_user() to enable and
disable access to userspace memory. However, it doesn't add these to
__clear_user(), which is used in the ptrace regset code.
As there's only one direct user of __clear_user() (the regset code),
and the time taken to set the AMR for KUAP purposes is going to
dominate the cost of a quick access_ok(), there's not much point
having a separate path.
Rename __clear_user() to __arch_clear_user(), and make __clear_user()
just call clear_user().
Reported-by: syzbot+f25ecf4b2982d8c7a640@syzkaller-ppc64.appspotmail.com
Reported-by: Daniel Axtens <dja@axtens.net>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection")
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
[mpe: Use __arch_clear_user() for the asm version like arm64 & nds32]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191209132221.15328-1-ajd@linux.ibm.com
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5cd623333e7cf4e3a334c70529268b65f2a6c2c7 upstream.
Today, when a function like strncpy_from_user() is called,
the userspace access protection is de-activated and re-activated
for every word read.
By implementing user_access_begin and friends, the protection
is de-activated at the beginning of the copy and re-activated at the
end.
Implement user_access_begin(), user_access_end() and
unsafe_get_user(), unsafe_put_user() and unsafe_copy_to_user()
For the time being, we keep user_access_save() and
user_access_restore() as nops.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/36d4fbf9e56a75994aca4ee2214c77b26a5a8d35.1579866752.git.christophe.leroy@c-s.fr
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Backported from commit de78a9c42a79 ("powerpc: Add a framework
for Kernel Userspace Access Protection"). Here we don't try to
add the KUAP framework, we just want the helper functions
because we want to put uaccess flush helpers in them.
In terms of fixes, we don't need commit 1d8f739b07bd ("powerpc/kuap:
Fix set direction in allow/prevent_user_access()") as we don't have
real KUAP. Likewise as all our allows are noops and all our prevents
are just flushes, we don't need commit 9dc086f1e9ef ("powerpc/futex:
Fix incorrect user access blocking") The other 2 fixes we do need.
The original description is:
This patch implements a framework for Kernel Userspace Access
Protection.
Then subarches will have the possibility to provide their own
implementation by providing setup_kuap() and
allow/prevent_user_access().
Some platforms will need to know the area accessed and whether it is
accessed from read, write or both. Therefore source, destination and
size and handed over to the two functions.
mpe: Rename to allow/prevent rather than unlock/lock, and add
read/write wrappers. Drop the 32-bit code for now until we have an
implementation for it. Add kuap to pt_regs for 64-bit as well as
32-bit. Don't split strings, use pr_crit_ratelimited().
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream.
IBM Power9 processors can speculatively operate on data in the L1 cache before
it has been completely validated, via a way-prediction mechanism. It is not possible
for an attacker to determine the contents of impermissible memory using this method,
since these systems implement a combination of hardware and software security measures
to prevent scenarios where protected data could be leaked.
However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that the
attacker controls. This can be used for example to speculatively bypass "kernel
user access prevention" techniques, as discovered by Anthony Steinhauser of
Google's Safeside Project. This is not an attack by itself, but there is a possibility
it could be used in conjunction with side-channels or other weaknesses in the
privileged code to construct an attack.
This issue can be mitigated by flushing the L1 cache between privilege boundaries
of concern. This patch flushes the L1 cache on kernel entry.
This is part of the fix for CVE-2020-4788.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
