The retry queue is intended to provide a temporary buffer in the case
of transient errors when communicating with auditd, it is not meant
as a long life queue, that functionality is provided by the hold
queue.
This patch fixes a problem identified by Seth where the retry queue
could grow uncontrollably if an auditd instance did not connect to
the kernel to drain the queues. This commit fixes this by doing the
following:
* Make sure we always call auditd_reset() if we decide the connection
with audit is really dead. There were some cases in
kauditd_hold_skb() where we did not reset the connection, this patch
relocates the reset calls to kauditd_thread() so all the error
conditions are caught and the connection reset. As a side effect,
this means we could move auditd_reset() and get rid of the forward
definition at the top of kernel/audit.c.
* We never checked the status of the auditd connection when
processing the main audit queue which meant that the retry queue
could grow unchecked. This patch adds a call to auditd_reset()
after the main queue has been processed if auditd is not connected,
the auditd_reset() call will make sure the retry and hold queues are
correctly managed/flushed so that the retry queue remains reasonable.
Cc: <stable@vger.kernel.org> # 4.10.x-: 5b52330bbf
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The commit 1259feddd0f8("pinctrl: samsung: Fix the width of
PINCFG_TYPE_DRV bitfields for Exynos5433") already fixed
the different width of PINCFG_TYPE_DRV from previous Exynos SoC.
However wrong merge conflict resolution was chosen in commit
7f36f5d11c ("Merge tag 'v4.10-rc6' into devel") effectively dropping
the changes for PINCFG_TYPE_DRV. Re-do them here.
The macro EXYNOS_PIN_BANK_EINTW is no longer used so remove it.
Fixes: 7f36f5d11c ("Merge tag 'v4.10-rc6' into devel")
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pull CIFS fixes from Steve French:
"This is a set of CIFS/SMB3 fixes for stable.
There is another set of four SMB3 reconnect fixes for stable in
progress but they are still being reviewed/tested, so didn't want to
wait any longer to send these five below"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
Reset TreeId to zero on SMB2 TREE_CONNECT
CIFS: Fix build failure with smb2
Introduce cifs_copy_file_range()
SMB3: Rename clone_range to copychunk_range
Handle mismatched open calls
Pull ARM fixes from Russell King:
"A number of ARM fixes:
- prevent oopses caused by dma_get_sgtable() and declared DMA
coherent memory
- fix boot failure on nommu caused by ID_PFR1 access
- a number of kprobes fixes from Jon Medhurst and Masami Hiramatsu"
* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8665/1: nommu: access ID_PFR1 only if CPUID scheme
ARM: dma-mapping: disallow dma_get_sgtable() for non-kernel managed memory
arm: kprobes: Align stack to 8-bytes in test code
arm: kprobes: Fix the return address of multiple kretprobes
arm: kprobes: Skip single-stepping in recursing path if possible
arm: kprobes: Allow to handle reentered kprobe on single-stepping
Here are 3 small fixes for 4.11-rc6. One resolves a reported issue with
sysfs files that NeilBrown found, one is a documenatation fix for the
stable kernel rules, and the last is a small MAINTAINERS file update for
kernfs.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are 3 small fixes for 4.11-rc6.
One resolves a reported issue with sysfs files that NeilBrown found,
one is a documenatation fix for the stable kernel rules, and the last
is a small MAINTAINERS file update for kernfs"
* tag 'driver-core-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
MAINTAINERS: separate out kernfs maintainership
sysfs: be careful of error returns from ops->show()
Documentation: stable-kernel-rules: fix stable-tag format
Here are a number of small IIO and staging driver fixes for 4.11-rc6.
Nothing big here, just iio fixes for reported issues, and an ashmem fix
for a very old bug that has been reported by a number of Android
vendors.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging/IIO driver rfixes from Greg KH:
"Here are a number of small IIO and staging driver fixes for 4.11-rc6.
Nothing big here, just iio fixes for reported issues, and an ashmem
fix for a very old bug that has been reported by a number of Android
vendors"
* tag 'staging-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: android: ashmem: lseek failed due to no FMODE_LSEEK.
iio: hid-sensor-attributes: Fix sensor property setting failure.
iio: accel: hid-sensor-accel-3d: Fix duplicate scan index error
iio: core: Fix IIO_VAL_FRACTIONAL_LOG2 for negative values
iio: st_pressure: initialize lps22hb bootime
iio: bmg160: reset chip when probing
iio: cros_ec_sensors: Fix return value to get raw and calibbias data.
Pull VFS fixes from Al Viro:
"statx followup fixes and a fix for stack-smashing on alpha"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
alpha: fix stack smashing in old_adjtimex(2)
statx: Include a mask for stx_attributes in struct statx
statx: Reserve the top bit of the mask for future struct expansion
xfs: report crtime and attribute flags to statx
ext4: Add statx support
statx: optimize copy of struct statx to userspace
statx: remove incorrect part of vfs_statx() comment
statx: reject unknown flags when using NULL path
Documentation/filesystems: fix documentation for ->getattr()
We should use proper RCU list APIs to manipulate help->expectations,
as we can dump the conntrack's expectations via nfnetlink, i.e. in
ctnetlink_exp_ct_dump_table(), where only rcu_read_lock is acquired.
So for list traversal, use hlist_for_each_entry_rcu; for list add/del,
use hlist_add_head_rcu and hlist_del_rcu.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For IPCTNL_MSG_EXP_GET, if the CTA_EXPECT_MASTER attr is specified, then
the NLM_F_DUMP request will dump the expectations related to this
connection tracking.
But we forget to check whether the conntrack has nf_conn_help or not,
so if nfct_help(ct) is NULL, oops will happen:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: ctnetlink_exp_ct_dump_table+0xf9/0x1e0 [nf_conntrack_netlink]
Call Trace:
? ctnetlink_exp_ct_dump_table+0x75/0x1e0 [nf_conntrack_netlink]
netlink_dump+0x124/0x2a0
__netlink_dump_start+0x161/0x190
ctnetlink_dump_exp_ct+0x16c/0x1bc [nf_conntrack_netlink]
? ctnetlink_exp_fill_info.constprop.33+0xf0/0xf0 [nf_conntrack_netlink]
? ctnetlink_glue_seqadj+0x20/0x20 [nf_conntrack_netlink]
ctnetlink_get_expect+0x32e/0x370 [nf_conntrack_netlink]
? debug_lockdep_rcu_enabled+0x1d/0x20
nfnetlink_rcv_msg+0x60a/0x6a9 [nfnetlink]
? nfnetlink_rcv_msg+0x1b9/0x6a9 [nfnetlink]
[...]
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
inet6_dev->addr_list is protected by inet6_dev->lock, so only using
rcu_read_lock is not enough, we should acquire read_lock_bh(&idev->lock)
before the inet6_dev->addr_list traversal.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
One CPU is doing ctnetlink_change_helper(), while another CPU is doing
unhelp() at the same time. So even if help->helper is not NULL at first,
the later statement strcmp(help->helper->name, ...) may still access
the NULL pointer.
So we must use rcu_read_lock and rcu_dereference to avoid such _bad_
thing happen.
Fixes: f95d7a46bc ("netfilter: ctnetlink: Fix regression in CTA_HELP processing")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When invoke __nf_conntrack_helper_find, it needs the rcu lock to
protect the helper module which would not be unloaded.
Now there are two caller nf_conntrack_helper_try_module_get and
ctnetlink_create_expect which don't hold rcu lock. And the other
callers left like ctnetlink_change_helper, ctnetlink_create_conntrack,
and ctnetlink_glue_attach_expect, they already hold the rcu lock
or spin_lock_bh.
Remove the rcu lock in functions nf_ct_helper_expectfn_find_by_name
and nf_ct_helper_expectfn_find_by_symbol. Because they return one pointer
which needs rcu lock, so their caller should hold the rcu lock, not in
these two functions.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Denys provided an awesome KASAN report pointing to an use
after free in xt_TCPMSS
I have provided three patches to fix this issue, either in xt_TCPMSS or
in xt_tcpudp.c. It seems xt_TCPMSS patch has the smallest possible
impact.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pull block fixes from Jens Axboe:
"Here's a pull request for 4.11-rc, fixing a set of issues mostly
centered around the new scheduling framework. These have been brewing
for a while, but split up into what we absolutely need in 4.11, and
what we can defer until 4.12. These are well tested, on both single
queue and multiqueue setups, and with and without shared tags. They
fix several hangs that have happened in testing.
This is obviously larger than I would have preferred at this point in
time, but I don't think we can shave much off this and still get the
desired results.
In detail, this pull request contains:
- a set of five fixes for NVMe, mostly from Christoph and one from
Roland.
- a series from Bart, fixing issues with dm-mq and SCSI shared tags
and scheduling. Note that one of those patches commit messages may
read like an optimization, but it is in fact an important fix for
queue restarts in particular.
- a series from Omar, most importantly fixing a hang with multiple
hardware queues when we fail to get a driver tag. Another important
fix in there is for resizing hardware queues, which nbd does when
handling multiple sockets for one connection.
- fixing an imbalance in putting the ctx for hctx request allocations
from Minchan"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq: Restart a single queue if tag sets are shared
dm rq: Avoid that request processing stalls sporadically
scsi: Avoid that SCSI queues get stuck
blk-mq: Introduce blk_mq_delay_run_hw_queue()
blk-mq: remap queues when adding/removing hardware queues
blk-mq-sched: fix crash in switch error path
blk-mq-sched: set up scheduler tags when bringing up new queues
blk-mq-sched: refactor scheduler initialization
blk-mq: use the right hctx when getting a driver tag fails
nvmet: fix byte swap in nvmet_parse_io_cmd
nvmet: fix byte swap in nvmet_execute_write_zeroes
nvmet: add missing byte swap in nvmet_get_smart_log
nvme: add missing byte swap in nvme_setup_discard
nvme: Correct NVMF enum values to match NVMe-oF rev 1.0
block: do not put mq context in blk_mq_alloc_request_hctx
An issue was detected with pin control hos on the Freescale i.MX after
the refactorings for more general group and function handling. We now
have the proper fix for this.
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Merge tag 'pinctrl-v4.11-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control fix from Linus Walleij:
"This late fix for pin control is hopefully the last I send this cycle.
The problem was detected early in the v4.11 release cycle and there
has been some back and forth on how to solve it. Sadly the proper fix
arrives late, but at least not too late.
An issue was detected with pin control on the Freescale i.MX after the
refactorings for more general group and function handling.
We now have the proper fix for this"
* tag 'pinctrl-v4.11-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: core: Fix pinctrl_register_and_init() with pinctrl_enable()
Headed to stable:
- disable HFSCR[TM] if TM is not supported, fixes a potential host kernel crash
triggered by a hostile guest, but only in configurations that no one uses
- don't try to fix up misaligned load-with-reservation instructions
- fix flush_(d|i)cache_range() called from modules on little endian kernels
- add missing global TLB invalidate if cxl is active
- fix missing preempt_disable() in crc32c-vpmsum
And a fix for selftests build changes that went in this release:
- selftests/powerpc: Fix standalone powerpc build
Thanks to:
Benjamin Herrenschmidt, Frederic Barrat, Oliver O'Halloran, Paul Mackerras.
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Merge tag 'powerpc-4.11-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some more powerpc fixes for 4.11:
Headed to stable:
- disable HFSCR[TM] if TM is not supported, fixes a potential host
kernel crash triggered by a hostile guest, but only in
configurations that no one uses
- don't try to fix up misaligned load-with-reservation instructions
- fix flush_(d|i)cache_range() called from modules on little endian
kernels
- add missing global TLB invalidate if cxl is active
- fix missing preempt_disable() in crc32c-vpmsum
And a fix for selftests build changes that went in this release:
- selftests/powerpc: Fix standalone powerpc build
Thanks to: Benjamin Herrenschmidt, Frederic Barrat, Oliver O'Halloran,
Paul Mackerras"
* tag 'powerpc-4.11-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/crypto/crc32c-vpmsum: Fix missing preempt_disable()
powerpc/mm: Add missing global TLB invalidate if cxl is active
powerpc/64: Fix flush_(d|i)cache_range() called from modules
powerpc: Don't try to fix up misaligned load-with-reservation instructions
powerpc: Disable HFSCR[TM] if TM is not supported
selftests/powerpc: Fix standalone powerpc build
In the case that compat_get_bitmap fails we do not want to copy the
bitmap to the user as it will contain uninitialized stack data and leak
sensitive data.
Signed-off-by: Chris Salls <salls@cs.ucsb.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, inputting the following command will succeed but actually the
value will be truncated:
# echo 0x12ffffffff > /proc/sys/net/ipv4/tcp_notsent_lowat
This is not friendly to the user, so instead, we should report error
when the value is larger than UINT_MAX.
Fixes: e7d316a02f ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Separate out kernfs from driver core and add myself as a
co-maintainer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'linux-can-fixes-for-4.12-20170404' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says:
====================
pull-request: can 2017-04-04
this is a pull request of two patches for net/master.
The first patch by Markus Marb fixes a register read access in the ifi driver.
The second patch by Geert Uytterhoeven for the rcar driver remove the printing
of a kernel virtual address.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
ops->show() can return a negative error code.
Commit 65da3484d9 ("sysfs: correctly handle short reads on PREALLOC attrs.")
(in v4.4) caused this to be stored in an unsigned 'size_t' variable, so errors
would look like large numbers.
As a result, if an error is returned, sysfs_kf_read() will return the
value of 'count', typically 4096.
Commit 17d0774f80 ("sysfs: correctly handle read offset on PREALLOC attrs")
(in v4.8) extended this error to use the unsigned large 'len' as a size for
memmove().
Consequently, if ->show returns an error, then the first read() on the
sysfs file will return 4096 and could return uninitialized memory to
user-space.
If the application performs a subsequent read, this will trigger a memmove()
with extremely large count, and is likely to crash the machine is bizarre ways.
This bug can currently only be triggered by reading from an md
sysfs attribute declared with __ATTR_PREALLOC() during the
brief period between when mddev_put() deletes an mddev from
the ->all_mddevs list, and when mddev_delayed_delete() - which is
scheduled on a workqueue - completes.
Before this, an error won't be returned by the ->show()
After this, the ->show() won't be called.
I can reproduce it reliably only by putting delay like
usleep_range(500000,700000);
early in mddev_delayed_delete(). Then after creating an
md device md0 run
echo clear > /sys/block/md0/md/array_state; cat /sys/block/md0/md/array_state
The bug can be triggered without the usleep.
Fixes: 65da3484d9 ("sysfs: correctly handle short reads on PREALLOC attrs.")
Fixes: 17d0774f80 ("sysfs: correctly handle read offset on PREALLOC attrs")
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A patch documenting how to specify which kernels a particular fix should
be backported to (seemingly) inadvertently added a minus sign after the
kernel version. This particular stable-tag format had never been used
prior to this patch, and was neither present when the patch in question
was first submitted (it was added in v2 without any comment).
Drop the minus sign to avoid any confusion.
Fixes: fdc81b7910 ("stable_kernel_rules: Add clause about specification of kernel versions to patch.")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because TCP_MIB_OUTRSTS is an important count, so always increase it
whatever send it successfully or not.
Now move the increment of TCP_MIB_OUTRSTS to the top of
tcp_send_active_reset to make sure it is increased always even though
fail to alloc skb.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Guillaume Nault says:
====================
l2tp: fix error handling of PPPoL2TP socket options
Fix pppol2tp_[gs]etsockopt() so that they don't ignore errors returned
by their helper functions.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
pppol2tp_getsockopt() doesn't take into account the error code returned
by pppol2tp_tunnel_getsockopt() or pppol2tp_session_getsockopt(). If
error occurs there, pppol2tp_getsockopt() continues unconditionally and
reports erroneous values.
Fixes: fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
pppol2tp_setsockopt() unconditionally overwrites the error value
returned by pppol2tp_tunnel_setsockopt() or
pppol2tp_session_setsockopt(), thus hiding errors from userspace.
Fixes: fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
vfs_llseek will check whether the file mode has
FMODE_LSEEK, no return failure. But ashmem can be
lseek, so add FMODE_LSEEK to ashmem file.
Comment From Greg Hackmann:
ashmem_llseek() passes the llseek() call through to the backing
shmem file. 91360b02ab ("ashmem: use vfs_llseek()") changed
this from directly calling the file's llseek() op into a VFS
layer call. This also adds a check for the FMODE_LSEEK bit, so
without that bit ashmem_llseek() now always fails with -ESPIPE.
Fixes: 91360b02ab ("ashmem: use vfs_llseek()")
Signed-off-by: Shuxiao Zhang <zhangshuxiao@xiaomi.com>
Tested-by: Greg Hackmann <ghackmann@google.com>
Cc: stable <stable@vger.kernel.org> # 3.18+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull sparc fixes from David Miller:
"Several fixes here, mostly having to due with either build errors or
memory corruptions depending upon whether you have THP enabled or not"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: remove unused wp_works_ok macro
sparc32: Export vac_cache_size to fix build error
sparc64: Fix memory corruption when THP is enabled
sparc64: Fix kernel panic due to erroneous #ifdef surrounding pmd_write()
arch/sparc: Avoid DCTI Couples
sparc64: kern_addr_valid regression
sparc64: Add support for 2G hugepages
sparc64: Fix size check in huge_pte_alloc
ARM:
- Fix a problem with GICv3 userspace save/restore
- Clarify GICv2 userspace save/restore ABI
- Be more careful in clearing GIC LRs
- Add missing synchronization primitive to our MMU handling code
PPC:
- Check for a NULL return from kzalloc
s390:
- Prevent translation exception errors on valid page tables for the
instruction-exection-protection support
x86:
- Fix Page-Modification Logging when running a nested guest
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář:
"ARM:
- Fix a problem with GICv3 userspace save/restore
- Clarify GICv2 userspace save/restore ABI
- Be more careful in clearing GIC LRs
- Add missing synchronization primitive to our MMU handling code
PPC:
- Check for a NULL return from kzalloc
s390:
- Prevent translation exception errors on valid page tables for the
instruction-exection-protection support
x86:
- Fix Page-Modification Logging when running a nested guest"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Check for kmalloc errors in ioctl
KVM: nVMX: initialize PML fields in vmcs02
KVM: nVMX: do not leak PML full vmexit to L1
KVM: arm/arm64: vgic: Fix GICC_PMR uaccess on GICv3 and clarify ABI
KVM: arm64: Ensure LRs are clear when they should be
kvm: arm/arm64: Fix locking for kvm_free_stage2_pgd
KVM: s390: remove change-recording override support
arm/arm64: KVM: Take mmap_sem in kvm_arch_prepare_memory_region
arm/arm64: KVM: Take mmap_sem in stage2_unmap_vm
Pull audit cleanup from Paul Moore:
"A week later than I had hoped, but as promised, here is the audit
uninline-fix we talked about during the last audit pull request.
The patch is slightly different than what we originally discussed as
it made more sense to keep the audit_signal_info() function in
auditsc.c rather than move it and bunch of other related
variables/definitions into audit.c/audit.h.
At some point in the future I need to look at how the audit code is
organized across kernel/audit*, I suspect we could do things a bit
better, but it doesn't seem like a -rc release is a good place for
that ;)
Regardless, this patch passes our tests without problem and looks good
for v4.11"
* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
audit: move audit_signal_info() into kernel/auditsc.c
Merge misc fixes from Andrew Morton:
"10 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: move pcp and lru-pcp draining into single wq
mailmap: update Yakir Yang email address
mm, swap_cgroup: reschedule when neeed in swap_cgroup_swapoff()
dax: fix radix tree insertion race
mm, thp: fix setting of defer+madvise thp defrag mode
ptrace: fix PTRACE_LISTEN race corrupting task->state
vmlinux.lds: add missing VMLINUX_SYMBOL macros
mm/page_alloc.c: fix print order in show_free_areas()
userfaultfd: report actual registered features in fdinfo
mm: fix page_vma_mapped_walk() for ksm pages
We currently have 2 specific WQ_RECLAIM workqueues in the mm code.
vmstat_wq for updating pcp stats and lru_add_drain_wq dedicated to drain
per cpu lru caches. This seems more than necessary because both can run
on a single WQ. Both do not block on locks requiring a memory
allocation nor perform any allocations themselves. We will save one
rescuer thread this way.
On the other hand drain_all_pages() queues work on the system wq which
doesn't have rescuer and so this depend on memory allocation (when all
workers are stuck allocating and new ones cannot be created).
Initially we thought this would be more of a theoretical problem but
Hugh Dickins has reported:
: 4.11-rc has been giving me hangs after hours of swapping load. At
: first they looked like memory leaks ("fork: Cannot allocate memory");
: but for no good reason I happened to do "cat /proc/sys/vm/stat_refresh"
: before looking at /proc/meminfo one time, and the stat_refresh stuck
: in D state, waiting for completion of flush_work like many kworkers.
: kthreadd waiting for completion of flush_work in drain_all_pages().
This worker should be using WQ_RECLAIM as well in order to guarantee a
forward progress. We can reuse the same one as for lru draining and
vmstat.
Link: http://lkml.kernel.org/r/20170307131751.24936-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Tested-by: Yang Li <pku.leo@gmail.com>
Tested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We got need_resched() warnings in swap_cgroup_swapoff() because
swap_cgroup_ctrl[type].length is particularly large.
Reschedule when needed.
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1704061315270.80559@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While running generic/340 in my test setup I hit the following race. It
can happen with kernels that support FS DAX PMDs, so v4.10 thru
v4.11-rc5.
Thread 1 Thread 2
-------- --------
dax_iomap_pmd_fault()
grab_mapping_entry()
spin_lock_irq()
get_unlocked_mapping_entry()
'entry' is NULL, can't call lock_slot()
spin_unlock_irq()
radix_tree_preload()
dax_iomap_pmd_fault()
grab_mapping_entry()
spin_lock_irq()
get_unlocked_mapping_entry()
...
lock_slot()
spin_unlock_irq()
dax_pmd_insert_mapping()
<inserts a PMD mapping>
spin_lock_irq()
__radix_tree_insert() fails with -EEXIST
<fall back to 4k fault, and die horribly
when inserting a 4k entry where a PMD exists>
The issue is that we have to drop mapping->tree_lock while calling
radix_tree_preload(), but since we didn't have a radix tree entry to
lock (unlike in the pmd_downgrade case) we have no protection against
Thread 2 coming along and inserting a PMD at the same index. For 4k
entries we handled this with a special-case response to -EEXIST coming
from the __radix_tree_insert(), but this doesn't save us for PMDs
because the -EEXIST case can also mean that we collided with a 4k entry
in the radix tree at a different index, but one that is covered by our
PMD range.
So, correctly handle both the 4k and 2M collision cases by explicitly
re-checking the radix tree for an entry at our index once we reacquire
mapping->tree_lock.
This patch has made it through a clean xfstests run with the current
v4.11-rc5 based linux/master, and it also ran generic/340 500 times in a
loop. It used to fail within the first 10 iterations.
Link: http://lkml.kernel.org/r/20170406212944.2866-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: <stable@vger.kernel.org> [4.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Setting thp defrag mode of "defer+madvise" actually sets "defer" in the
kernel due to the name similarity and the out-of-order way the string is
checked in defrag_store().
Check the string in the correct order so that
TRANSPARENT_HUGEPAGE_DEFRAG_KSWAPD_OR_MADV_FLAG is set appropriately for
"defer+madvise".
Fixes: 21440d7eb9 ("mm, thp: add new defer+madvise defrag option")
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1704051814420.137626@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In PT_SEIZED + LISTEN mode STOP/CONT signals cause a wakeup against
__TASK_TRACED. If this races with the ptrace_unfreeze_traced at the end
of a PTRACE_LISTEN, this can wake the task /after/ the check against
__TASK_TRACED, but before the reset of state to TASK_TRACED. This
causes it to instead clobber TASK_WAKING, allowing a subsequent wakeup
against TRACED while the task is still on the rq wake_list, corrupting
it.
Oleg said:
"The kernel can crash or this can lead to other hard-to-debug problems.
In short, "task->state = TASK_TRACED" in ptrace_unfreeze_traced()
assumes that nobody else can wake it up, but PTRACE_LISTEN breaks the
contract. Obviusly it is very wrong to manipulate task->state if this
task is already running, or WAKING, or it sleeps again"
[akpm@linux-foundation.org: coding-style fixes]
Fixes: 9899d11f ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL")
Link: http://lkml.kernel.org/r/xm26y3vfhmkp.fsf_-_@bsegall-linux.mtv.corp.google.com
Signed-off-by: Ben Segall <bsegall@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When __{start,end}_ro_after_init is referenced from C code, we run into
the following build errors on blackfin:
kernel/extable.c:169: undefined reference to `__start_ro_after_init'
kernel/extable.c:169: undefined reference to `__end_ro_after_init'
The build error is due to the fact that blackfin is one of the few
arches that prepends an underscore '_' to all symbols defined in C.
Fix this by wrapping __{start,end}_ro_after_init in vmlinux.lds.h with
VMLINUX_SYMBOL(), which adds the necessary prefix for arches that have
HAVE_UNDERSCORE_SYMBOL_PREFIX.
Link: http://lkml.kernel.org/r/1491259387-15869-1-git-send-email-jeyu@redhat.com
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Eddie Kovsky <ewk@edkovsky.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fdinfo for userfault file descriptor reports UFFD_API_FEATURES. Up
until recently, the UFFD_API_FEATURES was defined as 0, therefore
corresponding field in fdinfo always contained zero. Now, with
introduction of several additional features, UFFD_API_FEATURES is not
longer 0 and it seems better to report actual features requested for the
userfaultfd object described by the fdinfo.
First, the applications that were using userfault will still see zero at
the features field in fdinfo. Next, reporting actual features rather
than available features, gives clear indication of what userfault
features are used by an application.
Link: http://lkml.kernel.org/r/1491140181-22121-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Doug Smythies reports oops with KSM in this backtrace, I've been seeing
the same:
page_vma_mapped_walk+0xe6/0x5b0
page_referenced_one+0x91/0x1a0
rmap_walk_ksm+0x100/0x190
rmap_walk+0x4f/0x60
page_referenced+0x149/0x170
shrink_active_list+0x1c2/0x430
shrink_node_memcg+0x67a/0x7a0
shrink_node+0xe1/0x320
kswapd+0x34b/0x720
Just as observed in commit 4b0ece6fa0 ("mm: migrate: fix
remove_migration_pte() for ksm pages"), you cannot use page->index
calculations on ksm pages.
page_vma_mapped_walk() is relying on __vma_address(), where a ksm page
can lead it off the end of the page table, and into whatever nonsense is
in the next page, ending as an oops inside check_pte()'s pte_page().
KSM tells page_vma_mapped_walk() exactly where to look for the page, it
does not need any page->index calculation: and that's so also for all
the normal and file and anon pages - just not for THPs and their
subpages. Get out early in most cases: instead of a PageKsm test, move
down the earlier not-THP-page test, as suggested by Kirill.
I'm also slightly worried that this loop can stray into other vmas, so
added a vm_end test to prevent surprises; though I have not imagined
anything worse than a very contrived case, in which a page mlocked in
the next vma might be reclaimed because it is not mlocked in this vma.
Fixes: ace71a19ce ("mm: introduce page_vma_mapped_walk()")
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1704031104400.1118@eggly.anvils
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Doug Smythies <dsmythies@telus.net>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Without this fix (and another to the userspace component itself
described later), the kernel will be unable to process any OrangeFS
requests after the userspace component is restarted (due to a crash or
at the administrator's behest).
The bug here is that inside orangefs_remount, the orangefs_request_mutex
is locked. When the userspace component restarts while the filesystem
is mounted, it sends a ORANGEFS_DEV_REMOUNT_ALL ioctl to the device,
which causes the kernel to send it a few requests aimed at synchronizing
the state between the two. While this is happening the
orangefs_request_mutex is locked to prevent any other requests going
through.
This is only half of the bugfix. The other half is in the userspace
component which outright ignores(!) requests made before it considers
the filesystem remounted, which is after the ioctl returns. Of course
the ioctl doesn't return until after the userspace component responds to
the request it ignores. The userspace component has been changed to
allow ORANGEFS_VFS_OP_FEATURES regardless of the mount status.
Mike Marshall says:
"I've tested this patch against the fixed userspace part. This patch is
real important, I hope it can make it into 4.11...
Here's what happens when the userspace daemon is restarted, without
the patch:
=============================================
[ INFO: possible recursive locking detected ]
[ 4.10.0-00007-ge98bdb3 #1 Not tainted ]
---------------------------------------------
pvfs2-client-co/29032 is trying to acquire lock:
(orangefs_request_mutex){+.+.+.}, at: service_operation+0x3c7/0x7b0 [orangefs]
but task is already holding lock:
(orangefs_request_mutex){+.+.+.}, at: dispatch_ioctl_command+0x1bf/0x330 [orangefs]
CPU: 0 PID: 29032 Comm: pvfs2-client-co Not tainted 4.10.0-00007-ge98bdb3 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014
Call Trace:
__lock_acquire+0x7eb/0x1290
lock_acquire+0xe8/0x1d0
mutex_lock_killable_nested+0x6f/0x6e0
service_operation+0x3c7/0x7b0 [orangefs]
orangefs_remount+0xea/0x150 [orangefs]
dispatch_ioctl_command+0x227/0x330 [orangefs]
orangefs_devreq_ioctl+0x29/0x70 [orangefs]
do_vfs_ioctl+0xa3/0x6e0
SyS_ioctl+0x79/0x90"
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Acked-by: Mike Marshall <hubcap@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The recent extension of F-RTO 89fe18e44 ("tcp: extend F-RTO
to catch more spurious timeouts") interacts badly with certain
broken middle-boxes. These broken boxes modify and falsely raise
the receive window on the ACKs. During a timeout induced recovery,
F-RTO would send new data packets to probe if the timeout is false
or not. Since the receive window is falsely raised, the receiver
would silently drop these F-RTO packets. The recovery would take N
(exponentially backoff) timeouts to repair N packet losses. A TCP
performance killer.
Due to this unfortunate situation, this patch removes this extension
to revert F-RTO back to the RFC specification.
Fixes: 89fe18e44f ("tcp: extend F-RTO to catch more spurious timeouts")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To improve scalability, if hardware queues are shared, restart
a single hardware queue in round-robin fashion. Rename
blk_mq_sched_restart_queues() to reflect the new semantics.
Remove blk_mq_sched_mark_restart_queue() because this function
has no callers. Remove flag QUEUE_FLAG_RESTART because this
patch removes the code that uses this flag.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
While running the srp-test software I noticed that request
processing stalls sporadically at the beginning of a test, namely
when mkfs is run against a dm-mpath device. Every time when that
happened the following command was sufficient to resume request
processing:
echo run >/sys/kernel/debug/block/dm-0/state
This patch avoids that such request processing stalls occur. The
test I ran is as follows:
while srp-test/run_tests -d -r 30 -t 02-mq; do :; done
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Jens Axboe <axboe@fb.com>
If a .queue_rq() function returns BLK_MQ_RQ_QUEUE_BUSY then the block
driver that implements that function is responsible for rerunning the
hardware queue once requests can be queued again successfully.
commit 52d7f1b5c2 ("blk-mq: Avoid that requeueing starts stopped
queues") removed the blk_mq_stop_hw_queue() call from scsi_queue_rq()
for the BLK_MQ_RQ_QUEUE_BUSY case. Hence change all calls to functions
that are intended to rerun a busy queue such that these examine all
hardware queues instead of only stopped queues.
Since no other functions than scsi_internal_device_block() and
scsi_internal_device_unblock() should ever stop or restart a SCSI
queue, change the blk_mq_delay_queue() call into a
blk_mq_delay_run_hw_queue() call.
Fixes: commit 52d7f1b5c2 ("blk-mq: Avoid that requeueing starts stopped queues")
Fixes: commit 7e79dadce2 ("blk-mq: stop hardware queue in blk_mq_delay_queue()")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Long Li <longli@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Jens Axboe <axboe@fb.com>