There is a race between nfs4_state_manager() and
nfs_server_remove_lists() that happens during a nfsv3 mount.
The v3 mount notices there is already a supper block so
nfs_server_remove_lists() called which uses the nfs_client_lock
spin lock to synchronize access to the client list.
At the same time nfs4_state_manager() is running through
the client list looking for work to do, using the same
lock. When nfs4_state_manager() wins the race to the
list, a v3 client pointer is found and not ignored
properly which causes the panic.
Moving some protocol checks before the state checking
avoids the panic.
When we are doing compliance test with xHCI, we found that if we
enable CONFIG_USB_SUSPEND and plug in a bad device which causes
over-current condition to the root port, software will not be noticed.
The reason is that current code don't set hub->change_bits in
hub_activate() when over-current happens, and then hub_events() will
not check the port status because it thinks nothing changed.
If CONFIG_USB_SUSPEND is disabled, the interrupt pipe of the hub will
report the change and set hub->event_bits, and then hub_events() will
check what events happened.In this case over-current can be detected.
Signed-off-by: Shen Guang <shenguang10@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Frans Klaver <fransklaver@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Old code in ehci-hcd tries to expedite disabling endpoints after the
controller has stopped, by destroying the endpoint's associated QH
without first unlinking the QH. This was necessary back when the
driver wasn't so careful about keeping track of the controller's
state.
But now we are careful about it, and the driver knows that when the
controller isn't running, no unlinking delay is needed. Furthermore,
skipping the unlink step will trigger a BUG() in qh_destroy() when the
preceding QH is released, because the link pointer will be non-NULL.
Removing the lines that skip the unlinking step and go directly to
QH_STATE_IDLE fixes the problem.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Joe Lawrence <joe.lawrence@stratus.com> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds quirks for Entrega Technologies (later Xircom PortGear) USB-
SCSI converters. They use Shuttle Technology EUSB-01/EUSB-S1 chips. The
US_FL_SCM_MULT_TARG quirk is needed to allow multiple devices on the SCSI
chain to be accessed. Without it only the (single) device with SCSI ID 0
can be used.
The standalone converter sold by Entrega had model number U1-SC25. Xircom
acquired Entrega and re-branded the product line PortGear. The PortGear USB
to SCSI Converter (model PGSCSI) is internally identical to the Entrega
product, but later models may use a different USB ID. The Entrega-branded
units have USB ID 1645:0007, as does my Xircom PGSCSI, but the Windows and
Macintosh drivers also support 085A:0028.
Entrega also sold the "Mac USB Dock", which provides two USB ports, a Mac
(8-pin mini-DIN) serial port and a SCSI port. It appears to the computer as
a four-port hub, USB-serial, and USB-SCSI converters. The USB-SCSI part may
have initially used the same ID as the standalone U1-SC25 (1645:0007), but
later production used 085A:0026.
My Xircom PortGear PGSCSI has bcdDevice=0x0100. Units with bcdDevice=0x0133
probably also exist.
This patch adds quirks for 1645:0007, 085A:0026 and 085A:0028. The Windows
driver INF file also mentions 085A:0032 "PortStation SCSI Module", but I
couldn't find any mention of that actually existing in the wild; perhaps it
was cancelled before release?
Signed-off-by: Mark Knibbs <markk@clara.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Ariston Technologies iConnect 025 and iConnect 050 (also known as e.g.
iSCSI-50) are SCSI-USB converters which use Shuttle Technology/SCM
Microsystems chips. Only the connectors differ; both have the same USB ID.
The US_FL_SCM_MULT_TARG quirk is required to use SCSI devices with ID other
than 0.
I don't have one of these, but based on the other entries for Shuttle/
SCM-based converters this patch is very likely correct. I used 0x0000 and
0x9999 for bcdDeviceMin and bcdDeviceMax because I'm not sure which
bcdDevice value the products use.
Signed-off-by: Mark Knibbs <markk@clara.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Adaptec USBConnect 2000 is another SCSI-USB converter which uses
Shuttle Technology/SCM Microsystems chips. The US_FL_SCM_MULT_TARG quirk is
required to use SCSI devices with ID other than 0.
I don't have a USBConnect 2000, but based on the other entries for Shuttle/
SCM-based converters this patch is very likely correct. I used 0x0000 and
0x9999 for bcdDeviceMin and bcdDeviceMax because I'm not sure which
bcdDevice value the product uses.
Signed-off-by: Mark Knibbs <markk@clara.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Iomega Jaz USB Adapter is a SCSI-USB converter cable. The hardware
seems to be identical to e.g. the Microtech XpressSCSI, using a Shuttle/
SCM chip set. However its firmware restricts it to only work with Jaz
drives.
On connecting the cable a message like this appears four times in the log:
reset full speed USB device number 4 using uhci_hcd
That's non-fatal but the US_FL_SINGLE_LUN quirk fixes it.
Signed-off-by: Mark Knibbs <markk@clara.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During surprise device hotplug removal tests, it was observed that
hub_events may try to call usb_lock_device on a device that has already
been freed. Protect the usb_device by taking out a reference (under the
hub_event_lock) when hub_events pulls it off the list, returning the
reference after hub_events is finished using it.
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Suggested-by: David Bulkow <david.bulkow@stratus.com> for using kref Suggested-by: Alan Stern <stern@rowland.harvard.edu> for placement Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Resuming from hibernate (S4) will restart and re-initialize xHC.
The device contexts are freed and will be re-allocated later during device reset.
Usb core will disable link pm in device resume before device reset, which will
try to change the max exit latency, accessing the device contexts before they are re-allocated.
There is no need to zero (disable) the max exit latency when disabling hw lpm
for a freshly re-initialized xHC. So check that device context exists before
doing anything. The max exit latency will be set again after device reset when usb core
enables the link pm.
Reported-by: Imre Deak <imre.deak@intel.com> Tested-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If xhci initialization fails before the roothub bandwidth
domains (xhci->rh_bw[i]) are allocated it will oops when
trying to access rh_bw members in xhci_mem_cleanup().
Add back some PIDs that were mistakingly remove when reverting commit 73228a0538a7 ("USB: option,zte_ev: move most ZTE CDMA devices to
zte_ev"), which apparently did more than its commit message claimed in
that it not only moved some PIDs from option to zte_ev but also added
some new ones.
Fixes: 63a901c06e3c ("Revert "USB: option,zte_ev: move most ZTE CDMA
devices to zte_ev"")
Reported-by: Lei Liu <lei35151@163.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sierra Wireless Direct IP devices using the 68A3 product ID
can be configured for modes including a CDC ECM class function.
The known example uses interface numbers 12 and 13 for the ECM
control and data interfaces respectively, consistent with CDC
MBIM function interface numbering on other Sierra devices.
It seems cleaner to restrict this driver to the ff/ff/ff
vendor specific interfaces rather than increasing the already
long interface number blacklist. This should be more future
proof if Sierra adds more class functions using interface
numbers not yet in the blacklist.
Remove dublicate Qualcom PID 0x3197 which is already handled by the
moto-modem driver since commit 6986a978eec7 ("USB: add new moto_modem
driver for some Morotola phones").
This reverts commit 73228a0538a7 ("USB: option,zte_ev: move most ZTE
CDMA devices to zte_ev").
Move the IDs of the devices that were previously driven by the option
driver back to that driver.
As several users have reported, the zte_ev driver is causing random
disconnects as well as reconnect failures.
A closer analysis of the zte_ev setup code reveals that it consists of
standard CDC requests (SET/GET_LINE_CODING and SET_CONTROL_LINE_STATE)
but unfortunately fails to get some of those right. In particular, as
reported by Liu Lei, it fails to lower DTR/RTS on close. It also appears
that the control requests lack the interface argument.
Note that the zte_ev driver is based on code (once) distributed by ZTE
that still appears to originally have been reverse-engineered and bolted
onto the generic driver.
Since line control is already handled properly by the option driver, and
the SET/GET_LINE_CODING requests appears to be redundant (amounts to a
SET 9600 8N1), this is a first step in ultimately removing the redundant
zte_ev driver.
Note that AC2726 had already been moved back to option, and that some
IDs were in the device table of both drivers prior to the commit being
reverted.
Reported-by: Lei Liu <liu.lei78@zte.com.cn> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do not log normal interrupt-urb shutdowns as errors.
The option driver has always been logging any nonzero interrupt-urb
status as an error, including when the urb is killed during normal
operation.
Commit 9096f1fbba91 ("USB: usb_wwan: fix potential NULL-deref at
resume") moved the interrupt urb submission from port probe and release
to open and close, thus potentially increasing the number of these
false-positive error messages dramatically.
Reported-by: Ed Butler <ressy66@ausics.net> Tested-by: Ed Butler <ressy66@ausics.net> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to verify the number of ports requested by subdriver to avoid
writing beyond the end of fixed-size array in interface data.
The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of ports requested by a
subdriver (which could have been determined from device descriptors) did
not exceed this limit.
Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to verify the maximum number of endpoints per type to avoid
writing beyond the end of a stack-allocated array.
The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of endpoints of a certain
type reported by a device did not exceed this limit.
Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove restoring a6 on some return paths and instead modify and restore
it in a single place, using symbolic name.
Correctly restore a7 from PT_AREG7 in case of illegal a6 value.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current definition of TLBTEMP_BASE_2 is always 32K above the
TLBTEMP_BASE_1, whereas fast_second_level_miss handler for the TLBTEMP
region analyzes virtual address bit (PAGE_SHIFT + DCACHE_ALIAS_ORDER)
to determine TLBTEMP region where the fault happened. The size of the
TLBTEMP region is also checked incorrectly: not 64K, but twice data
cache way size (whicht may as well be less than the instruction cache
way size).
Fix TLBTEMP_BASE_2 to be TLBTEMP_BASE_1 + data cache way size.
Provide TLBTEMP_SIZE that is a greater of doubled data cache way size or
the instruction cache way size, and use it to determine if the second
level TLB miss occured in the TLBTEMP region.
Practical occurence of page faults in the TLBTEMP area is extremely
rare, this code can be tested by deletion of all w[di]tlb instructions
in the tlbtemp_mapping region.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With SMP and a lot of debug options enabled task_struct::thread gets out
of reach of s32i/l32i instructions with base pointing at task_struct,
breaking build with the following messages:
arch/xtensa/kernel/entry.S: Assembler messages:
arch/xtensa/kernel/entry.S:1002: Error: operand 3 of 'l32i.n' has invalid value '1048'
arch/xtensa/kernel/entry.S:1831: Error: operand 3 of 's32i.n' has invalid value '1040'
arch/xtensa/kernel/entry.S:1832: Error: operand 3 of 's32i.n' has invalid value '1044'
Change base to point to task_struct::thread in such cases.
Don't use a10 in _switch_to to save/restore prev pointer as a2 is not
clobbered.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Virtual address is translated to the XCHAL_KSEG_CACHED region in the
dma_free_coherent, but is checked to be in the 0...XCHAL_KSEG_SIZE
range.
Change check for end of the range from 'addr >= X' to 'addr > X - 1' to
handle the case of X == 0.
Replace 'if (C) BUG();' construct with 'BUG_ON(C);'.
Signed-off-by: Alan Douglas <adouglas@cadence.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes userspace code that builds on other architectures but fails
on xtensa due to references to structures that other architectures don't
refer to. E.g. this fixes the following issue with python-2.7.8:
python-2.7.8/Modules/termios.c:861:25: error: invalid application
of 'sizeof' to incomplete type 'struct serial_multiport_struct'
{"TIOCSERGETMULTI", TIOCSERGETMULTI},
python-2.7.8/Modules/termios.c:870:25: error: invalid application
of 'sizeof' to incomplete type 'struct serial_multiport_struct'
{"TIOCSERSETMULTI", TIOCSERSETMULTI},
python-2.7.8/Modules/termios.c:900:24: error: invalid application
of 'sizeof' to incomplete type 'struct tty_struct'
{"TIOCTTYGSTRUCT", TIOCTTYGSTRUCT},
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code waiting for fifo idle was incorrect and could possibly spin
forever under certain circumstances.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reported-by: Mark Sheldon <markshel@vmware.com> Reviewed-by: Jakob Bornecrantz <jakob@vmware.com> Reivewed-by: Mark Sheldon <markshel@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vblank waits in intel_tv_detect_type() are timing out for some
reason. This is a regression caused removing seemingly useless vblank
waits from the modeset seqeuence in:
drm/i915: Kill vblank waits after pipe enable on gmch platforms
So it turns out they weren't all entirely useless. Apparently the pipe
has to go through one full frame before we enable the TV port. Add a
vblank wait to intel_enable_tv() to make sure that happens.
Another approach was attempted by placing the vblank wait just after
enabling the port. The theory behind that attempt was that we need to
let the port stay enabled for one full frame before disabling it again
during load detection. But that didn't work, and we definitely must
have the vblank wait before enabling the port.
Cc: Alan Bartlett <ajb@elrepo.org> Tested-by: Alan Bartlett <ajb@elrepo.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79311 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The first command will remove the PCI device from the kernel's device
list so the second command won't see it right away. But as it registers
a PCI driver it'll see it on the third command. If the system happens to
match one of the DMI table entries we'll try to call a function in long
released memory and generate an Oops, at best.
Fix this by removing the bogus annotation.
Modpost should have caught that one but it ignores section reference
mismatches from the .rodata section. :/
Fixes: 25e341cfc33d ("drm/i915: quirk away broken OpRegion VBT") Fixes: 8ca4013d702d ("CHROMIUM: i915: Add DMI override to skip CRT...") Fixes: 425d244c8670 ("drm/i915: ignore LVDS on intel graphics systems...") Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Duncan Laurie <dlaurie@chromium.org> Cc: Jarod Wilson <jarod@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> # Can modpost be fixed? Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit "HID: logitech: perform bounds checking on device_id early
enough" unfortunately leaks some errors to dmesg which are not real
ones:
- if the report is not a DJ one, then there is not point in checking
the device_id
- the receiver (index 0) can also receive some notifications which
can be safely ignored given the current implementation
Move out the test regarding the report_id and also discards
printing errors when the receiver got notified.
Fixes: ad3e14d7c5268c2e24477c6ef54bbdf88add5d36 Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The report passed to us from transport driver could potentially be
arbitrarily large, therefore we better sanity-check it so that
magicmouse_emit_touch() gets only valid values of raw_id.
The report passed to us from transport driver could potentially be
arbitrarily large, therefore we better sanity-check it so that raw_data
that we hold in picolcd_pending structure are always kept within proper
bounds.
cfq_group_service_tree_add() is applying new_weight at the beginning of
the function via cfq_update_group_weight().
This actually allows weight to change between adding it to and subtracting
it from children_weight, and triggers WARN_ON_ONCE() in
cfq_group_service_tree_del(), or even causes oops by divide error during
vfr calculation in cfq_group_service_tree_add().
The detailed scenario is as follows:
1. Create blkio cgroups X and Y as a child of X.
Set X's weight to 500 and perform some I/O to apply new_weight.
This X's I/O completes before starting Y's I/O.
2. Y starts I/O and cfq_group_service_tree_add() is called with Y.
3. cfq_group_service_tree_add() walks up the tree during children_weight
calculation and adds parent X's weight (500) to children_weight of root.
children_weight becomes 500.
4. Set X's weight to 1000.
5. X starts I/O and cfq_group_service_tree_add() is called with X.
6. cfq_group_service_tree_add() applies its new_weight (1000).
7. I/O of Y completes and cfq_group_service_tree_del() is called with Y.
8. I/O of X completes and cfq_group_service_tree_del() is called with X.
9. cfq_group_service_tree_del() subtracts X's weight (1000) from
children_weight of root. children_weight becomes -500.
This triggers WARN_ON_ONCE().
10. Set X's weight to 500.
11. X starts I/O and cfq_group_service_tree_add() is called with X.
12. cfq_group_service_tree_add() applies its new_weight (500) and adds it
to children_weight of root. children_weight becomes 0. Calcularion of
vfr triggers oops by divide error.
weight should be updated right before adding it to children_weight.
When a driver is set up without the jack detection explicitly (either
by passing a model option or via a specific fixup), the pin powermap
of IDT/STAC codecs is set up wrongly, resulting in the silence
output. It's because of a logic failure in stac_init_power_map().
It tries to avoid creating a callback for the pins that have other
auto-hp and auto-mic callbacks, but the check is done in a wrong way
at a wrong time. The stac_init_power_map() should be called after
creating other jack detection ctls, and the jack callback should be
created only for jack-detectable widgets.
This patch fixes the check in stac_init_power_map() and its callee
at the right place, after snd_hda_gen_build_controls().
ALC1150 codec seems to need the COEF- and PLL-setups just like its
compatible ALC882 codec. Some machines (e.g. SunMicro X10SAT) show
the problem like too low output volumes unless the COEF setup is
applied.
snd_info_get_line() documents that its last parameter must be one
less than the buffer size, but this API design guarantees that
(literally) every caller gets it wrong.
Just change this parameter to have its obvious meaning.
Reported-by: Tommi Rantala <tt.rantala@gmail.com> Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I'm not sure what I was on when I wrote this, but when iterating over
the hardware watchpoint array (hbp_watch_array), our index is off by
ARM_MAX_BRP, so we walk off the end of our thread_struct...
... except, a dodgy condition in the loop means that it never executes
at all (bp cannot be NULL).
This patch fixes the code so that we remove the bp check and use the
correct index for accessing the watchpoint structures.
Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Epoll on trace_pipe can sometimes hang in a weird case. If the ring buffer is
empty when we set waiters_pending but an event shows up exactly at that moment
we can miss being woken up by the ring buffers irq work. Since
ring_buffer_empty() is inherently racey we will sometimes think that the buffer
is not empty. So we don't get woken up and we don't think there are any events
even though there were some ready when we added the watch, which makes us hang.
This patch fixes this by making sure that we are actually on the wait list
before we set waiters_pending, and add a memory barrier to make sure
ring_buffer_empty() is going to be correct.
There is a race condition in at91_do_twi_xfer when signals arrive.
If a signal is recieved while waiting for a transfer to complete
wait_for_completion_interruptible_timeout() will return -ERESTARTSYS.
This is not handled correctly resulting in interrupts still being
enabled and a transfer being in flight when we return.
Symptoms include a range of oopses and bus lockups. Oopses can happen
when the transfer completes because the interrupt handler will corrupt
the stack. If a new transfer is started before the interrupt fires
the controller will start a new transfer in the middle of the old one,
resulting in confused slaves and a locked bus.
To avoid this, use wait_for_completion_io_timeout instead so that we
don't have to deal with gracefully shutting down the transfer and
disabling the interrupts.
Signed-off-by: Simon Lindgren <simon@aqwary.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver was not bound checking the received length byte to ensure it was within the
the buffer size that is allocated for SMBus blocks. This resulted in buffer overflows
whenever an invalid length byte was received.
It also failed to ensure the length byte was not zero. If it received zero, it would end up
in an infinite loop as the at91_twi_read_next_byte function returned immediately without
allowing RHR to be read to clear the RXRDY interrupt.
Tested agaisnt a SMBus compliant battery.
Signed-off-by: Marek Roszko <mark.roszko@gmail.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nathan reports that we leak TLS information from the parent context
during an exec, as we don't clear the TLS registers when flushing the
thread state.
This patch updates the flushing code so that we:
(1) Unconditionally zero the tpidr_el0 register (since this is fully
context switched for native tasks and zeroed for compat tasks)
(2) Zero the tp_value state in thread_info before clearing the
tpidrr0_el0 register for compat tasks (since this is only writable
by the set_tls compat syscall and therefore not fully switched).
A missing compiler barrier is also added to the compat set_tls syscall.
Hidden away in the last 8 bytes of the buffer_list page is a solitary
statistic. It needs to be byte swapped or else ethtool -S will
produce numbers that terrify the user.
Since we do this in multiple places, create a helper function with a
comment explaining what is going on.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is not a complete fix, but it is verified to make the ring
initialization failures during resume much less likely.
We were not able to root-cause this bug (likely HW-specific to Gen4 chips)
yet. This is therefore used as a ducttape before problem is fully
understood and proper fix created, so that people don't suffer from
completely unusable systems in the meantime.
We can use "unsigned int" instead of "atomic_t" by updating start_pool
variable under _manager->lock. This patch will make it possible to avoid
skipping when choosing a pool to shrink in round-robin style, after next
patch changes mutex_lock(_manager->lock) to !mutex_trylock(_manager->lork).
list_empty(&_manager->pools) being false before taking _manager->lock
does not guarantee that _manager->npools != 0 after taking _manager->lock
because _manager->npools is updated under _manager->lock.
display_timings_release calls kfree on the display_timings object passed
to it. Calling kfree after it is wrong. SLUB debug showed the following
warning:
=============================================================================
BUG kmalloc-64 (Tainted: G W ): Object already free
-----------------------------------------------------------------------------
Disabling lock debugging due to kernel taint
INFO: Allocated in of_get_display_timings+0x2c/0x214 age=601 cpu=0
pid=884
__slab_alloc.constprop.79+0x2e0/0x33c
kmem_cache_alloc+0xac/0xdc
of_get_display_timings+0x2c/0x214
panel_probe+0x7c/0x314 [tilcdc]
platform_drv_probe+0x18/0x48
[..snip..]
INFO: Freed in panel_destroy+0x18/0x3c [tilcdc] age=0 cpu=0 pid=907
__slab_free+0x34/0x330
panel_destroy+0x18/0x3c [tilcdc]
tilcdc_unload+0xd0/0x118 [tilcdc]
drm_dev_unregister+0x24/0x98
[..snip..]
Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar> Tested-by: Darren Etheridge <detheridge@ti.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver did not unregister the allocated framebuffer, which caused
memory leaks (and memory manager WARNs) when unloading. Also, the
framebuffer device under /dev still existed after unloading.
Add a call to drm_fbdev_cma_fini when unloading the module to prevent
both issues.
Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar> Tested-by: Darren Etheridge <detheridge@ti.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver assumes that endpoint 4 is always an interrupt endpoint.
Unfortunately the type differs between high-speed and full-speed
configurations while in the former case it is indeed an interrupt
endpoint this is not true for the latter case - here it is a bulk
endpoint. When sending URBs with the wrong type the kernel will
generate a warning message including backtrace. In this specific
case there will be a huge amount of warnings which can bring the system
to freeze.
To fix this we are now sending URBs to endpoint 4 using the type
found in the endpoint descriptor.
A side note: The carl9170 firmware currently specifies endpoint 4 as
interrupt endpoint even in the full-speed configuration but this has
no relevance because before this firmware is loaded the endpoint type
is as described above and after the firmware is running the stick is not
reenumerated and so the old descriptor is used.
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We preallocate a few of the message types we get back from the mon. If we
get a larger message than we are expecting, fall back to trying to allocate
a new one instead of blindly using the one we have.
Some Atmel TPMs provide completely wrong timeouts from their
TPM_CAP_PROP_TIS_TIMEOUT query. This patch detects that and returns
new correct values via a DID/VID table in the TIS driver.
Tested on ARM using an AT97SC3204T FW version 37.16
[PHuewe: without this fix these 'broken' Atmel TPMs won't function on
older kernels] Signed-off-by: "Berg, Christopher" <Christopher.Berg@atmel.com> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
[bwh: Backported to 3.10:
- Adjust filename, context
- s/chip->ops->/chip->vendor./] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Josef Bacik found a performance regression between 3.2 and 3.10 and
narrowed it down to commit bfcfaa77bdf0 ("vfs: use 'unsigned long'
accesses for dcache name comparison and hashing"). He reports:
On xfs on a fio card this goes at about 20k dir/sec with 3.2, and 12k
dir/sec with 3.10. This is because we spend waaaaay more time in
__d_lookup on 3.10 than in 3.2.
The new hashing function for strings is suboptimal for <
sizeof(unsigned long) string names (and hell even > sizeof(unsigned
long) string names that I've tested). I broke out the old hashing
function and the new one into a userspace helper to get real numbers
and this is what I'm getting:
Old hash table had 1000000 entries, 0 dupes, 0 max dupes
New hash table had 12628 entries, 987372 dupes, 900 max dupes
We had 11400 buckets with a p50 of 30 dupes, p90 of 240 dupes, p99 of 567 dupes for the new hash
My test does the hash, and then does the d_hash into a integer pointer
array the same size as the dentry hash table on my system, and then
just increments the value at the address we got to see how many
entries we overlap with.
As you can see the old hash function ended up with all 1 million
entries in their own bucket, whereas the new one they are only
distributed among ~12.5k buckets, which is why we're using so much
more CPU in __d_lookup".
The reason for this hash regression is two-fold:
- On 64-bit architectures the down-mixing of the original 64-bit
word-at-a-time hash into the final 32-bit hash value is very
simplistic and suboptimal, and just adds the two 32-bit parts
together.
In particular, because there is no bit shuffling and the mixing
boundary is also a byte boundary, similar character patterns in the
low and high word easily end up just canceling each other out.
- the old byte-at-a-time hash mixed each byte into the final hash as it
hashed the path component name, resulting in the low bits of the hash
generally being a good source of hash data. That is not true for the
word-at-a-time case, and the hash data is distributed among all the
bits.
The fix is the same in both cases: do a better job of mixing the bits up
and using as much of the hash data as possible. We already have the
"hash_32|64()" functions to do that.
Reported-by: Josef Bacik <jbacik@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Chris Mason <clm@fb.com> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
D_HASH{MASK,BITS} are used once each, both in the same function (d_hash()).
At this point they are actively misguiding - they imply that values are
compiler constants, which is no longer true.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If scsi_remove_host() is invoked after a SCSI device has been blocked,
if the fast_io_fail_tmo or dev_loss_tmo work gets scheduled on the
workqueue executing srp_remove_work() and if an I/O request is
scheduled after the SCSI device had been blocked by e.g. multipathd
then the following deadlock can occur:
While a queue is being destroyed, all the blkgs are destroyed and its
->root_blkg pointer is set to NULL. If someone else starts to drain
while the queue is in this state, the following oops happens.
776687bce42b ("block, blk-mq: draining can't be skipped even if
bypass_depth was non-zero") made it easier to trigger this bug by
making blk_queue_bypass_start() drain even when it loses the first
bypass test to blk_cleanup_queue(); however, the bug has always been
there even before the commit as blk_queue_bypass_start() could race
against queue destruction, win the initial bypass test but perform the
actual draining after blk_cleanup_queue() already destroyed all blkgs.
Fix it by skippping calling into policy draining if all the blkgs are
already gone.
commit 65b97cf6b8de introduced in v3.7 caused a regression
by using a reversed CS_MASK thus causing omap_calculate_ecc to
always fail. As the NAND base driver never checks for .calculate()'s
return value, the zeroed ECC values are used as is without showing
any error to the user. However, this won't work and the NAND device
won't be guarded by any error code.
Fix the issue by using the correct mask.
Code was tested on omap3beagle using the following procedure
- flash the primary bootloader (MLO) from the kernel to the first
NAND partition using nandwrite.
- boot the board from NAND. This utilizes OMAP ROM loader that
relies on 1-bit Hamming code ECC.
Fixes: 65b97cf6b8de (mtd: nand: omap2: handle nand on gpmc) Signed-off-by: Roger Quadros <rogerq@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It seems that the corrupted partition header on my mtd device triggers
a bug in the ftl. In function build_maps() it will allocate the buffers
needed by the mtd partition, but if something goes wrong such as kmalloc
failure, mtd read error or invalid partition header parameter, it will
free all allocated buffers and then return non-zero. In my case, it
seems that partition header parameter 'NumTransferUnits' is invalid.
And the ftl_freepart() is a function which free all the partition
buffers allocated by build_maps(). Given the build_maps() is a self
cleaning function, so there is no need to invoke this function even
if build_maps() return with error. Otherwise it will causes the
buffers to be freed twice and then weird things would happen.
Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing code calls server->ops->close() that is not
right. This causes XFS test generic/310 to fail. Fix this
by using server->ops->closedir() function.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing code uses the old MAX_NAME constant. This causes
XFS test generic/013 to fail. Fix it by replacing MAX_NAME with
PATH_MAX that SMB1 uses. Also remove an unused MAX_NAME constant
definition.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we requests rename we also need to update attributes
of both source and target parent directories. Not doing it
causes generic/309 xfstest to fail on SMB2 mounts. Fix this
by marking these directories for force revalidating.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we get into read_into_pages() from cifs_readv_receive() and then
loose a network, we issue cifs_reconnect that moves all mids to
a private list and issue their callbacks. The callback of the async
read request sets a mid to retry, frees it and wakes up a process
that waits on the rdata completion.
After the connection is established we return from read_into_pages()
with a short read, use the mid that was freed before and try to read
the remaining data from the a newly created socket. Both actions are
not what we want to do. In reconnect cases (-EAGAIN) we should not
mask off the error with a short read but should return the error
code instead.
Acked-by: Jeff Layton <jlayton@samba.org> Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing mapping causes unlink() call to return error after delete
operation. Changing the mapping to -EACCES makes the client process
the call like CIFS protocol does - reset dos attributes with ATTR_READONLY
flag masked off and retry the operation.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We hard code cephx auth ticket buffer size to 256 bytes. This isn't
enough for any moderate setups and, in case tickets themselves are not
encrypted, leads to buffer overflows (ceph_x_decrypt() errors out, but
ceph_decode_copy() doesn't - it's just a memcpy() wrapper). Since the
buffer is allocated dynamically anyway, allocated it a bit later, at
the point where we know how much is going to be needed.
Add a helper for processing individual cephx auth tickets. Needed for
the next commit, which deals with allocating ticket buffers. (Most of
the diff here is whitespace - view with git diff -b).
Determining ->last_piece based on the value of ->page_offset + length
is incorrect because length here is the length of the entire message.
->last_piece set to false even if page array data item length is <=
PAGE_SIZE, which results in invalid length passed to
ceph_tcp_{send,recv}page() and causes various asserts to fire.
Currently we don't abort recovery on a write error if the write error
to the recovering device was triggerd by normal IO (as opposed to
recovery IO).
This means that for one bitmap region, the recovery might write to the
recovering device for a few sectors, then not bother for subsequent
sectors (as it never writes to failed devices). In this case
the bitmap bit will be cleared, but it really shouldn't.
The result is that if the recovering device fails and is then re-added
(after fixing whatever hardware problem triggerred the failure),
the second recovery won't redo the region it was in the middle of,
so some of the device will not be recovered properly.
If we abort the recovery, the region being processes will be cancelled
(bit not cleared) and the whole region will be retried.
As the bug can result in data corruption the patch is suitable for
-stable. For kernels prior to 3.11 there is a conflict in raid10.c
which will require care.
xfs is using truncate_pagecache_range to invalidate the page cache
during DIO reads. This is different from the other filesystems who
only invalidate pages during DIO writes.
truncate_pagecache_range is meant to be used when we are freeing the
underlying data structs from disk, so it will zero any partial
ranges in the page. This means a DIO read can zero out part of the
page cache page, and it is possible the page will stay in cache.
buffered reads will find an up to date page with zeros instead of
the data actually on disk.
This patch fixes things by using invalidate_inode_pages2_range
instead. It preserves the page cache invalidation, but won't zero
any pages.
[dchinner: catch error and warn if it fails. Comment.]
Signed-off-by: Chris Mason <clm@fb.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Similar to direct IO reads, direct IO writes are using
truncate_pagecache_range to invalidate the page cache. This is
incorrect due to the sub-block zeroing in the page cache that
truncate_pagecache_range() triggers.
This patch fixes things by using invalidate_inode_pages2_range
instead. It preserves the page cache invalidation, but won't zero
any pages.
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
where 1190 extents EOF from 0x54000 to 0x5e569. When the direct IO
write attempts to invalidate the cached page over this range, it
fails with -EBUSY and so any attempt to do page invalidation fails.
The real question is this: Why can't that page be invalidated after
it has been written to disk and cleaned?
Well, there's data on the first two buffers in the page (1k block
size, 4k page), but the third buffer on the page (i.e. beyond EOF)
is failing drop_buffers because it's bh->b_state == 0x3, which is
BH_Uptodate | BH_Dirty. IOWs, there's dirty buffers beyond EOF. Say
what?
OK, set_buffer_dirty() is called on all buffers from
__set_page_buffers_dirty(), regardless of whether the buffer is
beyond EOF or not, which means that when we get to ->writepage,
we have buffers marked dirty beyond EOF that we need to clean.
So, we need to implement our own .set_page_dirty method that
doesn't dirty buffers beyond EOF.
This is messy because the buffer code is not meant to be shared
and it has interesting locking issues on the buffer dirty bits.
So just copy and paste it and then modify it to suit what we need.
Note: the solutions the other filesystems and generic block code use
of marking the buffers clean in ->writepage does not work for XFS.
It still leaves dirty buffers beyond EOF and invalidations still
fail. Hence rather than play whack-a-mole, this patch simply
prevents those buffers from being dirtied in the first place.
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This was caused by dquot buffer readahead not attaching a verifier
structure to the buffer when readahead was issued, resulting in the
followup read of the buffer finding a valid buffer and so not
attaching new verifiers to the buffer as part of the read.
Also, when a verifier failure occurs, we then read the buffer
without verifiers. Attach the verifiers manually after this read so
that if the buffer is then written it will be verified that the
corruption has been repaired.
Further, when flushing a dquot we don't ask for a verifier when
reading in the dquot buffer the dquot belongs to. Most of the time
this isn't an issue because the buffer is still cached, but when it
is not cached it will result in writing the dquot buffer without
having the verfier attached.
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the user creates a listening cm_id with backlog of 0 the IWCM ends
up not allowing any connection requests at all. The correct behavior
is for the IWCM to pick a default value if the user backlog parameter
is zero.
Lustre from version 1.8.8 onward uses a backlog of 0, which breaks
iwarp support without this fix.
Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a raid10 commences a resync/recovery/reshape it allocates
some buffer space.
When a resync/recovery completes the buffer space is freed. But not
when the reshape completes.
This can result in a small memory leak.
There is a subtle side-effect of this bug. When a RAID10 is reshaped
to a larger array (more devices), the reshape is immediately followed
by a "resync" of the new space. This "resync" will use the buffer
space which was allocated for "reshape". This can cause problems
including a "BUG" in the SCSI layer. So this is suitable for -stable.
raid10 reshape clears unwanted bits from a bio->bi_flags using
a method which, while clumsy, worked until 3.10 when BIO_OWNS_VEC
was added.
Since then it clears that bit but shouldn't. This results in a
memory leak.
So change to used the approved method of clearing unwanted bits.
As this causes a memory leak which can consume all of memory
the fix is suitable for -stable.
During recovery of a double-degraded RAID6 it is possible for
some blocks not to be recovered properly, leading to corruption.
If a write happens to one block in a stripe that would be written to a
missing device, and at the same time that stripe is recovering data
to the other missing device, then that recovered data may not be written.
This patch skips, in the double-degraded case, an optimisation that is
only safe for single-degraded arrays.
Bug was introduced in 2.6.32 and fix is suitable for any kernel since
then. In an older kernel with separate handle_stripe5() and
handle_stripe6() functions the patch must change handle_stripe6().
Fixes: 6c0069c0ae9659e3a91b68eaed06a5c6c37f45c8 Cc: Yuri Tikhonov <yur@emcraft.com> Cc: Dan Williams <dan.j.williams@intel.com> Reported-by: "Manibalan P" <pmanibalan@amiindia.co.in> Tested-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1090423 Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commits 08c30aca9e698faddebd34f81e1196295f9dc063 "Bluetooth: Remove
RFCOMM session refcnt" and 8ff52f7d04d9cc31f1e81dcf9a2ba6335ed34905
"Bluetooth: Return RFCOMM session ptrs to avoid freed session"
allow rfcomm_recv_ua and rfcomm_session_close to delete the session
(and free the corresponding socket) and propagate NULL session pointer
to the upper callers.
Additional fix is required to terminate the loop in rfcomm_process_rx
function to avoid use of freed 'sk' memory.
The issue is only reproducible with kernel option CONFIG_PAGE_POISONING
enabled making freed memory being changed and filled up with fixed char
value used to unmask use-after-free issues.
Kenton Varda <kenton@sandstorm.io> discovered that by remounting a
read-only bind mount read-only in a user namespace the
MNT_LOCK_READONLY bit would be cleared, allowing an unprivileged user
to the remount a read-only mount read-write.
Upon review of the code in remount it was discovered that the code allowed
nosuid, noexec, and nodev to be cleared. It was also discovered that
the code was allowing the per mount atime flags to be changed.
The first naive patch to fix these issues contained the flaw that using
default atime settings when remounting a filesystem could be disallowed.
To avoid this problems in the future add tests to ensure unprivileged
remounts are succeeding and failing at the appropriate times.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since March 2009 the kernel has treated the state that if no
MS_..ATIME flags are passed then the kernel defaults to relatime.
Defaulting to relatime instead of the existing atime state during a
remount is silly, and causes problems in practice for people who don't
specify any MS_...ATIME flags and to get the default filesystem atime
setting. Those users may encounter a permission error because the
default atime setting does not work.
A default that does not work and causes permission problems is
ridiculous, so preserve the existing value to have a default
atime setting that is always guaranteed to work.
Using the default atime setting in this way is particularly
interesting for applications built to run in restricted userspace
environments without /proc mounted, as the existing atime mount
options of a filesystem can not be read from /proc/mounts.
In practice this fixes user space that uses the default atime
setting on remount that are broken by the permission checks
keeping less privileged users from changing more privileged users
atime settings.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While invesgiating the issue where in "mount --bind -oremount,ro ..."
would result in later "mount --bind -oremount,rw" succeeding even if
the mount started off locked I realized that there are several
additional mount flags that should be locked and are not.
In particular MNT_NOSUID, MNT_NODEV, MNT_NOEXEC, and the atime
flags in addition to MNT_READONLY should all be locked. These
flags are all per superblock, can all be changed with MS_BIND,
and should not be changable if set by a more privileged user.
The following additions to the current logic are added in this patch.
- nosuid may not be clearable by a less privileged user.
- nodev may not be clearable by a less privielged user.
- noexec may not be clearable by a less privileged user.
- atime flags may not be changeable by a less privileged user.
The logic with atime is that always setting atime on access is a
global policy and backup software and auditing software could break if
atime bits are not updated (when they are configured to be updated),
and serious performance degradation could result (DOS attack) if atime
updates happen when they have been explicitly disabled. Therefore an
unprivileged user should not be able to mess with the atime bits set
by a more privileged user.
The additional restrictions are implemented with the addition of
MNT_LOCK_NOSUID, MNT_LOCK_NODEV, MNT_LOCK_NOEXEC, and MNT_LOCK_ATIME
mnt flags.
Taken together these changes and the fixes for MNT_LOCK_READONLY
should make it safe for an unprivileged user to create a user
namespace and to call "mount --bind -o remount,... ..." without
the danger of mount flags being changed maliciously.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no races as locked mount flags are guaranteed to never change.
Moving the test into do_remount makes it more visible, and ensures all
filesystem remounts pass the MNT_LOCK_READONLY permission check. This
second case is not an issue today as filesystem remounts are guarded
by capable(CAP_DAC_ADMIN) and thus will always fail in less privileged
mount namespaces, but it could become an issue in the future.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kenton Varda <kenton@sandstorm.io> discovered that by remounting a
read-only bind mount read-only in a user namespace the
MNT_LOCK_READONLY bit would be cleared, allowing an unprivileged user
to the remount a read-only mount read-write.
Correct this by replacing the mask of mount flags to preserve
with a mask of mount flags that may be changed, and preserve
all others. This ensures that any future bugs with this mask and
remount will fail in an easy to detect way where new mount flags
simply won't change.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Debugging this bug, which triggers when the rb_iter_peek() loops too
many times (more than 2 times), I discovered there's a case that can
cause that function to legitimately loop 3 times!
rb_iter_peek() is different than rb_buffer_peek() as the rb_buffer_peek()
only deals with the reader page (it's for consuming reads). The
rb_iter_peek() is for traversing the buffer without consuming it, and as
such, it can loop for one more reason. That is, if we hit the end of
the reader page or any page, it will go to the next page and try again.
That is, we have this:
1. iter->head > iter->head_page->page->commit
(rb_inc_iter() which moves the iter to the next page)
try again
2. event = rb_iter_head_event()
event->type_len == RINGBUF_TYPE_TIME_EXTEND
rb_advance_iter()
try again
3. read the event.
But we never get to 3, because the count is greater than 2 and we
cause the WARNING and return NULL.
Up the counter to 3.
Fixes: 69d1b839f7ee "ring-buffer: Bind time extend and data events together" Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When performing a consuming read, the ring buffer swaps out a
page from the ring buffer with a empty page and this page that
was swapped out becomes the new reader page. The reader page
is owned by the reader and since it was swapped out of the ring
buffer, writers do not have access to it (there's an exception
to that rule, but it's out of scope for this commit).
When reading the "trace" file, it is a non consuming read, which
means that the data in the ring buffer will not be modified.
When the trace file is opened, a ring buffer iterator is allocated
and writes to the ring buffer are disabled, such that the iterator
will not have issues iterating over the data.
Although the ring buffer disabled writes, it does not disable other
reads, or even consuming reads. If a consuming read happens, then
the iterator is reset and starts reading from the beginning again.
My tests would sometimes trigger this bug on my i386 box:
Which was the __trace_find_cmdline() function complaining about the pid
in the event record being negative.
After adding more test cases, this would trigger more often. Strangely
enough, it would never trigger on a single test, but instead would trigger
only when running all the tests. I believe that was the case because it
required one of the tests to be shutting down via delayed instances while
a new test started up.
After spending several days debugging this, I found that it was caused by
the iterator becoming corrupted. Debugging further, I found out why
the iterator became corrupted. It happened with the rb_iter_reset().
As consuming reads may not read the full reader page, and only part
of it, there's a "read" field to know where the last read took place.
The iterator, must also start at the read position. In the rb_iter_reset()
code, if the reader page was disconnected from the ring buffer, the iterator
would start at the head page within the ring buffer (where writes still
happen). But the mistake there was that it still used the "read" field
to start the iterator on the head page, where it should always start
at zero because readers never read from within the ring buffer where
writes occur.
I originally wrote a patch to have it set the iter->head to 0 instead
of iter->head_page->read, but then I questioned why it wasn't always
setting the iter to point to the reader page, as the reader page is
still valid. The list_empty(reader_page->list) just means that it was
successful in swapping out. But the reader_page may still have data.
There was a bug report a long time ago that was not reproducible that
had something about trace_pipe (consuming read) not matching trace
(iterator read). This may explain why that happened.
Anyway, the correct answer to this bug is to always use the reader page
an not reset the iterator to inside the writable ring buffer.
Fixes: d769041f8653 "ring_buffer: implement new locking" Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix this by reversing the order acpi_processor_cst_has_changed() does
thigs -- let it first execute the protection against CPU hotplug by
calling get_online_cpus() and obtain the cpuidle lock only after that (and
perform the symmentric change when allowing CPUs hotplug again and
dropping cpuidle lock).
Spotted by lockdep.
Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / thirdparty / kernel / stable.git / log
