The critical section protected by usbhid->lock in hid_ctrl() is too
big and because of this it causes a recursive deadlock. "Too big" means
the case statement and the call to hid_input_report() do not need to be
protected by the spinlock (no URB operations are done inside them).
The deadlock happens because in certain rare cases drivers try to grab
the lock while handling the ctrl irq which grabs the lock before them
as described above. For example newer wacom tablets like 056a:033c try
to reschedule proximity reads from wacom_intuos_schedule_prox_event()
calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report()
which tries to grab the usbhid lock already held by hid_ctrl().
There are two ways to get out of this deadlock:
1. Make the drivers work "around" the ctrl critical region, in the
wacom case for ex. by delaying the scheduling of the proximity read
request itself to a workqueue.
2. Shrink the critical region so the usbhid lock protects only the
instructions which modify usbhid state, calling hid_input_report()
with the spinlock unlocked, allowing the device driver to grab the
lock first, finish and then grab the lock afterwards in hid_ctrl().
This patch implements the 2nd solution.
Signed-off-by: Ioan-Adrian Ratiu <adi@adirat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.2: adjust context] Cc: Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Poison pointer values should be small enough to find a room in
non-mmap'able/hardly-mmap'able space. E.g. on x86 "poison pointer space"
is located starting from 0x0. Given unprivileged users cannot mmap
anything below mmap_min_addr, it should be safe to use poison pointers
lower than mmap_min_addr.
The current poison pointer values of LIST_POISON{1,2} might be too big for
mmap_min_addr values equal or less than 1 MB (common case, e.g. Ubuntu
uses only 0x10000). There is little point to use such a big value given
the "poison pointer space" below 1 MB is not yet exhausted. Changing it
to a smaller value solves the problem for small mmap_min_addr setups.
The values are suggested by Solar Designer:
http://www.openwall.com/lists/oss-security/2015/05/02/6
Signed-off-by: Vasily Kulikov <segoon@openwall.com> Cc: Solar Designer <solar@openwall.com> Cc: Thomas Gleixner <tglx@linutronix.de> 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> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The aiptek driver crashes in aiptek_probe() when a specially crafted USB
device without endpoints is detected. This fix adds a check that the device
has proper configuration expected by the driver. Also an error return value
is changed to more matching one in one of the error paths.
The fork of a process with four page table levels is broken since
git commit 6252d702c5311ce9 "[S390] dynamic page tables."
All new mm contexts are created with three page table levels and
an asce limit of 4TB. If the parent has four levels dup_mmap will
add vmas to the new context which are outside of the asce limit.
The subsequent call to copy_page_range will walk the three level
page table structure of the new process with non-zero pgd and pud
indexes. This leads to memory clobbers as the pgd_index *and* the
pud_index is added to the mm->pgd pointer without a pgd_deref
in between.
The init_new_context() function is selecting the number of page
table levels for a new context. The function is used by mm_init()
which in turn is called by dup_mm() and mm_alloc(). These two are
used by fork() and exec(). The init_new_context() function can
distinguish the two cases by looking at mm->context.asce_limit,
for fork() the mm struct has been copied and the number of page
table levels may not change. For exec() the mm_alloc() function
set the new mm structure to zero, in this case a three-level page
table is created as the temporary stack space is located at
STACK_TOP_MAX = 4TB.
This fixes CVE-2016-2143.
Reported-by: Marcin Kościelnicki <koriakin@0x04.net> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[bwh: Backported to 3.2:
- 31-bit s390 is still supported so keep the #ifdef CONFIG_64BIT conditions
- Split page table locks are not implemented for PMDs so don't call
pgtable_pmd_page_{ctor,dtor}()
- PMDs are not accounted so don't call mm_inc_nr_pmds()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It turns out that commit can cause problems for systems with multiple
GPUs, and causes X to hang on at least a HP Pavilion dv7 with hybrid
graphics.
This got noticed originally in 4.4.4, where this patch had already
gotten back-ported, but 4.5-rc7 was verified to have the same problem.
Alexander Deucher says:
"It looks like you have a muxed system so I suspect what's happening is
that one of the display is being reported as connected for both the
IGP and the dGPU and then the desktop environment gets confused or
there some sort problem in the detect functions since the mux is not
switched to the dGPU. I don't see an easy fix unless Dave has any
ideas. I'd say just revert for now"
Reported-by: Jörg-Volker Peetz <jvpeetz@web.de> Acked-by: Alexander Deucher <Alexander.Deucher@amd.com> Cc: Dave Airlie <airlied@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ubi_start_leb_change() allocates too few bytes.
ubi_more_leb_change_data() will write up to req->upd_bytes +
ubi->min_io_size bytes.
Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Avoid sending a partially initialised `siginfo_t' structure along SIGFPE
signals issued from `do_ov' and `do_trap_or_bp', leading to information
leaking from the kernel stack.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The current reserved_tailroom calculation fails to take hlen and tlen into
account.
skb:
[__hlen__|__data____________|__tlen___|__extra__]
^ ^
head skb_end_offset
In this representation, hlen + data + tlen is the size passed to alloc_skb.
"extra" is the extra space made available in __alloc_skb because of
rounding up by kmalloc. We can reorder the representation like so:
[__hlen__|__data____________|__extra__|__tlen___]
^ ^
head skb_end_offset
The maximum space available for ip headers and payload without
fragmentation is min(mtu, data + extra). Therefore,
reserved_tailroom
= data + extra + tlen - min(mtu, data + extra)
= skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen)
= skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen)
Compare the second line to the current expression:
reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset)
and we can see that hlen and tlen are not taken into account.
The min() in the third line can be expanded into:
if mtu < skb_tailroom - tlen:
reserved_tailroom = skb_tailroom - mtu
else:
reserved_tailroom = tlen
Depending on hlen, tlen, mtu and the number of multicast address records,
the current code may output skbs that have less tailroom than
dev->needed_tailroom or it may output more skbs than needed because not all
space available is used.
Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs") Signed-off-by: Benjamin Poirier <bpoirier@suse.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
According to IBTA spec v1.3 section 12.7.19, QPs should use GRH when
the path returned by the SA has hop-limit > 0. Currently, we do that
only for the > 1 case, fix that.
Fixes: 6d969a471ba1 ('IB/sa: Add ib_init_ah_from_path()') Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Pause/unpause graph tracing around do_suspend_lowlevel as it has
inconsistent call/return info after it jumps to the wakeup vector.
The graph trace buffer will otherwise become misaligned and
may eventually crash and hang on suspend.
To reproduce the issue and test the fix:
Run a function_graph trace over suspend/resume and set the graph
function to suspend_devices_and_enter. This consistently hangs the
system without this fix.
Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The OSS sequencer client tries to drain the pending events at
releasing. Unfortunately, as spotted by syzkaller fuzzer, this may
lead to an unkillable process state when the event has been queued at
the far future. Since the process being released can't be signaled
any longer, it remains and waits for the echo-back event in that far
future.
Back to history, the draining feature was implemented at the time we
misinterpreted POSIX definition for blocking file operation.
Actually, such a behavior is superfluous at release, and we should
just release the device as is instead of keeping it up forever.
This patch just removes the draining call that may block the release
for too long time unexpectedly.
The DRC Mode like "AIF1DRC1 Mode" and EQ Mode like "AIF1.1 EQ Mode" in
wm8994 codec driver are enum ctls, while the current driver accesses
wrongly via value.integer.value[]. They have to be via
value.enumerated.item[] instead.
Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
"MBC Mode", "VSS Mode", "VSS HPF Mode" and "Enhanced EQ Mode" ctls in
wm8958 codec driver are enum, while the current driver accesses
wrongly via value.integer.value[]. They have to be via
value.enumerated.item[] instead.
Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@kernel.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The Parrot NMEA GPS Flight Recorder is a USB composite device
consisting of hub, flash storage, and cp210x usb to serial chip.
It is an accessory to the mass-produced Parrot AR Drone 2.
The device emits standard NMEA messages which make the it compatible
with NMEA compatible software. It was tested using gpsd version 3.11-3
as an NMEA interpreter and using the official Parrot Flight Recorder.
Signed-off-by: Vittorio Alfieri <vittorio88@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
snd-hdspm driver accesses enum item values (int) instead of boolean
values (long) wrongly for some ctl elements. This patch fixes them.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: drop change to snd_hdspm_put_system_sample_rate()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The timer user status compat ioctl returned the bogus struct used for
64bit architectures instead of the 32bit one. This patch addresses
it to return the proper struct.
Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The delete opration can allocate additional space on the HPFS filesystem
due to btree split. The HPFS driver checks in advance if there is
available space, so that it won't corrupt the btree if we run out of space
during splitting.
If there is not enough available space, the HPFS driver attempted to
truncate the file, but this results in a deadlock since the commit 7dd29d8d865efdb00c0542a5d2c87af8c52ea6c7 ("HPFS: Introduce a global mutex
and lock it on every callback from VFS").
This patch removes the code that tries to truncate the file and -ENOSPC is
returned instead. If the user hits -ENOSPC on delete, he should try to
delete other files (that are stored in a leaf btree node), so that the
delete operation will make some space for deleting the file stored in
non-leaf btree node.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.2: deleted code is slightly different] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
pmd_trans_unstable()/pmd_none_or_trans_huge_or_clear_bad() were
introduced to locklessy (but atomically) detect when a pmd is a regular
(stable) pmd or when the pmd is unstable and can infinitely transition
from pmd_none() and pmd_trans_huge() from under us, while only holding
the mmap_sem for reading (for writing not).
While holding the mmap_sem only for reading, MADV_DONTNEED can run from
under us and so before we can assume the pmd to be a regular stable pmd
we need to compare it against pmd_none() and pmd_trans_huge() in an
atomic way, with pmd_trans_unstable(). The old pmd_trans_huge() left a
tiny window for a race.
Useful applications are unlikely to notice the difference as doing
MADV_DONTNEED concurrently with a page fault would lead to undefined
behavior.
[akpm@linux-foundation.org: tidy up comment grammar/layout] Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-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>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit d63c7dd5bcb9 ("ipr: Fix out-of-bounds null overwrite") removed
the end of line handling when storing the update_fw sysfs attribute.
This changed the userpace API because it started refusing writes
terminated by a line feed, which broke the update tools we already have.
This patch re-adds that handling, so both a write terminated by a line
feed or not can make it through with the update.
Fixes: d63c7dd5bcb9 ("ipr: Fix out-of-bounds null overwrite") Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Cc: Insu Yun <wuninsu@gmail.com> Acked-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Return value of snprintf is not bound by size value, 2nd argument.
(https://www.kernel.org/doc/htmldocs/kernel-api/API-snprintf.html).
Return value is number of printed chars, can be larger than 2nd
argument. Therefore, it can write null byte out of bounds ofbuffer.
Since snprintf puts null, it does not need to put additional null byte.
Signed-off-by: Insu Yun <wuninsu@gmail.com> Reviewed-by: Shane Seymour <shane.seymour@hpe.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The id buffer in ata_device is a DMA target, but it isn't explicitly
cacheline aligned. Due to this, adjacent fields can be overwritten with
stale data from memory on non coherent architectures. As a result, the
kernel is sometimes unable to communicate with an ATA device.
Fix this by ensuring that the id buffer is cacheline aligned.
This issue is similar to that fixed by Commit 84bda12af31f
("libata: align ap->sector_buf").
When a directory is deleted, we don't take too much care about killing off
all the dirents that belong to it — on the basis that on remount, the scan
will conclude that the directory is dead anyway.
This doesn't work though, when the deleted directory contained a child
directory which was moved *out*. In the early stages of the fs build
we can then end up with an apparent hard link, with the child directory
appearing both in its true location, and as a child of the original
directory which are this stage of the mount process we don't *yet* know
is defunct.
To resolve this, take out the early special-casing of the "directories
shall not have hard links" rule in jffs2_build_inode_pass1(), and let the
normal nlink processing happen for directories as well as other inodes.
Then later in the build process we can set ic->pino_nlink to the parent
inode#, as is required for directories during normal operaton, instead
of the nlink. And complain only *then* about hard links which are still
in evidence even after killing off all the unreachable paths.
Reported-by: Liu Song <liu.song11@zte.com.cn> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
With this fix, all code paths should now be obtaining the page lock before
f->sem.
Reported-by: Szabó Tamás <sztomi89@gmail.com> Tested-by: Thomas Betker <thomas.betker@rohde-schwarz.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This reverts commit 5ffd3412ae55
("jffs2: Fix lock acquisition order bug in jffs2_write_begin").
The commit modified jffs2_write_begin() to remove a deadlock with
jffs2_garbage_collect_live(), but this introduced new deadlocks found
by multiple users. page_lock() actually has to be called before
mutex_lock(&c->alloc_sem) or mutex_lock(&f->sem) because
jffs2_write_end() and jffs2_readpage() are called with the page locked,
and they acquire c->alloc_sem and f->sem, resp.
In other words, the lock order in jffs2_write_begin() was correct, and
it is the jffs2_garbage_collect_live() path that has to be changed.
Revert the commit to get rid of the new deadlocks, and to clear the way
for a better fix of the original deadlock.
Reported-by: Deng Chao <deng.chao1@zte.com.cn> Reported-by: Ming Liu <liu.ming50@gmail.com> Reported-by: wangzaiwei <wangzaiwei@top-vision.cn> Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
[bwh: Backported to 3.2: use D1(printk(KERN_DEBUG ...)) instead of
jffs2_dbg(1, ...)] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In async_pf we try to allocate with NOWAIT to get an element quickly
or fail. This code also handle failures gracefully. Lets silence
potential page allocation failures under load.
The qword_get() function NUL-terminates its output buffer. If the input
string is in hex format \xXXXX... and the same length as the output
buffer, there is an off-by-one:
This patch ensures the NUL terminator doesn't fall outside the output
buffer.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The value 5000 was put here with the addition of the timeout field to
ieee80211_start_tx_ba_session. It was originally added in mac80211 to
save resources for drivers like iwlwifi, which only supports a limited
number of concurrent aggregation sessions.
Since iwlwifi does not use minstrel_ht and other drivers don't need
this, 0 is a better default - especially since there have been
recent reports of aggregation setup related issues reproduced with
ath9k. This should improve stability without causing any adverse
effects.
Acked-by: Avery Pennarun <apenwarr@gmail.com> Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch fixes the problem that more CAN messages could be sent to the
interface as could be send on the CAN bus. This was more likely for slow baud
rates. The sleeping _start_xmit was woken up in the _write_bulk_callback. Under
heavy TX load this produced another bulk transfer without checking the
free_slots variable and hence caused the overflow in the interface.
Signed-off-by: Gerhard Uttenthaler <uttenthaler@ems-wuensche.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In __request_region, if a conflict with a BUSY and MUXED resource is
detected, then the caller goes to sleep and waits for the resource to be
released. A pointer on the conflicting resource is kept. At wake-up
this pointer is used as a parent to retry to request the region.
A first problem is that this pointer might well be invalid (if for
example the conflicting resource have already been freed). Another
problem is that the next call to __request_region() fails to detect a
remaining conflict. The previously conflicting resource is passed as a
parameter and __request_region() will look for a conflict among the
children of this resource and not at the resource itself. It is likely
to succeed anyway, even if there is still a conflict.
Instead, the parent of the conflicting resource should be passed to
__request_region().
As a fix, this patch doesn't update the parent resource pointer in the
case we have to wait for a muxed region right after.
Reported-and-tested-by: Vincent Pelletier <plr.vincent@gmail.com> Signed-off-by: Simon Guinot <simon.guinot@sequanux.org> Tested-by: Vincent Donnefort <vdonnefort@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ext4 can update bh->b_state non-atomically in _ext4_get_block() and
ext4_da_get_block_prep(). Usually this is fine since bh is just a
temporary storage for mapping information on stack but in some cases it
can be fully living bh attached to a page. In such case non-atomic
update of bh->b_state can race with an atomic update which then gets
lost. Usually when we are mapping bh and thus updating bh->b_state
non-atomically, nobody else touches the bh and so things work out fine
but there is one case to especially worry about: ext4_finish_bio() uses
BH_Uptodate_Lock on the first bh in the page to synchronize handling of
PageWriteback state. So when blocksize < pagesize, we can be atomically
modifying bh->b_state of a buffer that actually isn't under IO and thus
can race e.g. with delalloc trying to map that buffer. The result is
that we can mistakenly set / clear BH_Uptodate_Lock bit resulting in the
corruption of PageWriteback state or missed unlock of BH_Uptodate_Lock.
Fix the problem by always updating bh->b_state bits atomically.
Reported-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[bwh: Backported to 3.2:
- s/READ_ONCE/ACCESS_ONCE/
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Add USB ID for cp2104/5 devices on GE B650v3 and B850v3 boards.
Signed-off-by: Ken Lin <ken.lin@advantech.com.tw> Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
RdropOvflw counts overrun of HW buffer, therefore should
be used for rx_fifo_errors only.
Currently RdropOvflw counter is mistakenly also set into
rx_missed_errors and rx_over_errors too, which makes the
device total dropped packets accounting to show wrong results.
Fix that. Use it for rx_fifo_errors only.
Fixes: c27a02cd94d6 ('mlx4_en: Add driver for Mellanox ConnectX 10GbE NIC') Signed-off-by: Amir Vadai <amir@vadai.me> Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The assignement of EP transfer resources was not handled properly in the
dwc3 driver. Commit aebda6187181 ("usb: dwc3: Reset the transfer
resource index on SET_INTERFACE") previously fixed one aspect of this
where resources may be exhausted with multiple calls to SET_INTERFACE.
However, it introduced an issue where composite devices with multiple
interfaces can be assigned the same transfer resources for different
endpoints. This patch solves both issues.
The assignment of transfer resources cannot perfectly follow the data
book due to the fact that the controller driver does not have all
knowledge of the configuration in advance. It is given this information
piecemeal by the composite gadget framework after every
SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
programming model in this scenario can cause errors. For two reasons:
1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION and
SET_INTERFACE (8.1.5). This is incorrect in the scenario of multiple
interfaces.
2) The databook does not mention doing more DEPXFERCFG for new endpoint
on alt setting (8.1.6).
The following simplified method is used instead:
All hardware endpoints can be assigned a transfer resource and this
setting will stay persistent until either a core reset or hibernation.
So whenever we do a DEPSTARTCFG(0) we can go ahead and do DEPXFERCFG for
every hardware endpoint as well. We are guaranteed that there are as
many transfer resources as endpoints.
This patch triggers off of the calling dwc3_gadget_start_config() for
EP0-out, which always happens first, and which should only happen in one
of the above conditions.
Fixes: aebda6187181 ("usb: dwc3: Reset the transfer resource index on SET_INTERFACE") Reported-by: Ravi Babu <ravibabu@ti.com> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Data corruption issues were observed in tests which initiated
a system crash/reset while accessing BTT devices. This problem
is reproducible.
The BTT driver calls pmem_rw_bytes() to update data in pmem
devices. This interface calls __copy_user_nocache(), which
uses non-temporal stores so that the stores to pmem are
persistent.
__copy_user_nocache() uses non-temporal stores when a request
size is 8 bytes or larger (and is aligned by 8 bytes). The
BTT driver updates the BTT map table, which entry size is
4 bytes. Therefore, updates to the map table entries remain
cached, and are not written to pmem after a crash.
Change __copy_user_nocache() to use non-temporal store when
a request size is 4 bytes. The change extends the current
byte-copy path for a less-than-8-bytes request, and does not
add any overhead to the regular path.
Reported-and-tested-by: Micah Parrish <micah.parrish@hpe.com> Reported-and-tested-by: Brian Boylston <brian.boylston@hpe.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: linux-nvdimm@lists.01.org Link: http://lkml.kernel.org/r/1455225857-12039-3-git-send-email-toshi.kani@hpe.com
[ Small readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: aadjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S,
and replace them with _ASM_EXTABLE() macros; this will allow us to
change the format and type of the exception table entries.
The unix_dgram_sendmsg routine use the following test
if (unlikely(unix_peer(other) != sk && unix_recvq_full(other))) {
to determine if sk and other are in an n:1 association (either
established via connect or by using sendto to send messages to an
unrelated socket identified by address). This isn't correct as the
specified address could have been bound to the sending socket itself or
because this socket could have been connected to itself by the time of
the unix_peer_get but disconnected before the unix_state_lock(other). In
both cases, the if-block would be entered despite other == sk which
might either block the sender unintentionally or lead to trying to unlock
the same spin lock twice for a non-blocking send. Add a other != sk
check to guard against this.
Fixes: 7d267278a9ec ("unix: avoid use-after-free in ep_remove_wait_queue") Reported-By: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Tested-by: Philipp Hahn <pmhahn@pmhahn.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Change it such that err is only set if an error condition was detected.
Fixes: 3822b5c2fc62 ("af_unix: Revert 'lock_interruptible' in stream receive code") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The commit [7f0973e973cd: ALSA: seq: Fix lockdep warnings due to
double mutex locks] split the management of two linked lists (source
and destination) into two individual calls for avoiding the AB/BA
deadlock. However, this may leave the possible double deletion of one
of two lists when the counterpart is being deleted concurrently.
It ends up with a list corruption, as revealed by syzkaller fuzzer.
This patch fixes it by checking the list emptiness and skipping the
deletion and the following process.
BugLink: http://lkml.kernel.org/r/CACT4Y+bay9qsrz6dQu31EcGaH9XwfW7o3oBzSQUG9fMszoh=Sg@mail.gmail.com Fixes: 7f0973e973cd ('ALSA: seq: Fix lockdep warnings due to 'double mutex locks) Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In my randconfig tests, I came across a bug that involves several
components:
* gcc-4.9 through at least 5.3
* CONFIG_GCOV_PROFILE_ALL enabling -fprofile-arcs for all files
* CONFIG_PROFILE_ALL_BRANCHES overriding every if()
* The optimized implementation of do_div() that tries to
replace a library call with an division by multiplication
* code in drivers/media/dvb-frontends/zl10353.c doing
In this case, gcc fails to determine whether the divisor
in do_div() is __builtin_constant_p(). In particular, it
concludes that __builtin_constant_p(adc_clock) is false, while
__builtin_constant_p(!!adc_clock) is true.
That in turn throws off the logic in do_div() that also uses
__builtin_constant_p(), and instead of picking either the
constant- optimized division, and the code in ilog2() that uses
__builtin_constant_p() to figure out whether it knows the answer at
compile time. The result is a link error from failing to find
multiple symbols that should never have been called based on
the __builtin_constant_p():
dvb-frontends/zl10353.c:138: undefined reference to `____ilog2_NaN'
dvb-frontends/zl10353.c:138: undefined reference to `__aeabi_uldivmod'
ERROR: "____ilog2_NaN" [drivers/media/dvb-frontends/zl10353.ko] undefined!
ERROR: "__aeabi_uldivmod" [drivers/media/dvb-frontends/zl10353.ko] undefined!
This patch avoids the problem by changing __trace_if() to check
whether the condition is known at compile-time to be nonzero, rather
than checking whether it is actually a constant.
I see this one link error in roughly one out of 1600 randconfig builds
on ARM, and the patch fixes all known instances.
Link: http://lkml.kernel.org/r/1455312410-1058841-1-git-send-email-arnd@arndb.de Acked-by: Nicolas Pitre <nico@linaro.org> Fixes: ab3c9c686e22 ("branch tracer, intel-iommu: fix build with CONFIG_BRANCH_TRACER=y") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The tracepoint infrastructure uses RCU sched protection to enable and
disable tracepoints safely. There are some instances where tracepoints are
used in infrastructure code (like kfree()) that get called after a CPU is
going offline, and perhaps when it is coming back online but hasn't been
registered yet.
This can probuce the following warning:
[ INFO: suspicious RCU usage. ] 4.4.0-00006-g0fe53e8-dirty #34 Tainted: G S
-------------------------------
include/trace/events/kmem.h:141 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from offline CPU! rcu_scheduler_active = 1, debug_locks = 1
no locks held by swapper/8/0.
This warning is not a false positive either. RCU is not protecting code that
is being executed while the CPU is offline.
Instead of playing "whack-a-mole(TM)" and adding conditional statements to
the tracepoints we find that are used in this instance, simply add a
cpu_online() test to the tracepoint code where the tracepoint will be
ignored if the CPU is offline.
Use of raw_smp_processor_id() is fine, as there should never be a case where
the tracepoint code goes from running on a CPU that is online and suddenly
gets migrated to a CPU that is offline.
When multiple concurrent writes happen on the ALSA sequencer device
right after the open, it may try to allocate vmalloc buffer for each
write and leak some of them. It's because the presence check and the
assignment of the buffer is done outside the spinlock for the pool.
The fix is to move the check and the assignment into the spinlock.
(The current implementation is suboptimal, as there can be multiple
unnecessary vmallocs because the allocation is done before the check
in the spinlock. But the pool size is already checked beforehand, so
this isn't a big problem; that is, the only possible path is the
multiple writes before any pool assignment, and practically seen, the
current coverage should be "good enough".)
When we call pci_scan_root_bus we would pass in 'sd' (sysdata)
pointer which was an 'pcifront_sd' structure. However in the
pci_device_add it expects that the 'sd' is 'struct sysdata' and
sets the dev->node to what is in sd->node (offset 4):
That is an hole - filled with garbage as we used kmalloc instead of
kzalloc (the second problem).
This patch fixes the issue by:
1) Use kzalloc to initialize to a well known state.
2) Put 'struct pci_sysdata' at the start of 'pcifront_sd'. That
way access to the 'node' will access the right offset.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 8135cf8b092723dbfcc611fe6fdcb3a36c9951c5 (xen/pciback: Save
xen_pci_op commands before processing it) broke enabling MSI-X because
it would never copy the resulting vectors into the response. The
number of vectors requested was being overwritten by the return value
(typically zero for success).
Save the number of vectors before processing the op, so the correct
number of vectors are copied afterwards.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 408fb0e5aa7fda0059db282ff58c3b2a4278baa0 (xen/pciback: Don't
allow MSI-X ops if PCI_COMMAND_MEMORY is not set) prevented enabling
MSI-X on passed-through virtual functions, because it checked the VF
for PCI_COMMAND_MEMORY but this is not a valid bit for VFs.
Instead, check the physical function for PCI_COMMAND_MEMORY.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
As reported by Soohoon Lee, the HDIO_GET_32BIT ioctl does not
work correctly in compat mode with libata.
I have investigated the issue further and found multiple problems
that all appeared with the same commit that originally introduced
HDIO_GET_32BIT handling in libata back in linux-2.6.8 and presumably
also linux-2.4, as the code uses "copy_to_user(arg, &val, 1)" to copy
a 'long' variable containing either 0 or 1 to user space.
The problems with this are:
* On big-endian machines, this will always write a zero because it
stores the wrong byte into user space.
* In compat mode, the upper three bytes of the variable are updated
by the compat_hdio_ioctl() function, but they now contain
uninitialized stack data.
* The hdparm tool calling this ioctl uses a 'static long' variable
to store the result. This means at least the upper bytes are
initialized to zero, but calling another ioctl like HDIO_GET_MULTCOUNT
would fill them with data that remains stale when the low byte
is overwritten. Fortunately libata doesn't implement any of the
affected ioctl commands, so this would only happen when we query
both an IDE and an ATA device in the same command such as
"hdparm -N -c /dev/hda /dev/sda"
* The libata code for unknown reasons started using ATA_IOC_GET_IO32
and ATA_IOC_SET_IO32 as aliases for HDIO_GET_32BIT and HDIO_SET_32BIT,
while the ioctl commands that were added later use the normal
HDIO_* names. This is harmless but rather confusing.
This addresses all four issues by changing the code to use put_user()
on an 'unsigned long' variable in HDIO_GET_32BIT, like the IDE subsystem
does, and by clarifying the names of the ioctl commands.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reported-by: Soohoon Lee <Soohoon.Lee@f5.com> Tested-by: Soohoon Lee <Soohoon.Lee@f5.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Add refcount to the DASD device when a summary unit check worker is
scheduled. This prevents that the device is set offline with worker
in place.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The channel checks the specified length and the provided amount of
data for CCWs and provides an incorrect length error if the size does
not match. Under z/VM with simulation activated the length may get
changed. Having the suppress length indication bit set is stated as
good CCW coding practice and avoids errors under z/VM.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The setup_ntlmv2_rsp() function may return positive value ENOMEM instead
of -ENOMEM in case of kmalloc failure.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Since cfg80211 frequently takes actions from its netdev notifier
call, wireless extensions messages could still be ordered badly
since the wext netdev notifier, since wext is built into the
kernel, runs before the cfg80211 netdev notifier. For example,
the following can happen:
5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default
link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
5: wlan1: <BROADCAST,MULTICAST,UP>
link/ether
when setting the interface down causes the wext message.
To also fix this, export the wireless_nlevent_flush() function
and also call it from the cfg80211 notifier.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[bwh: Backported to 3.2:
- Add default case in cfg80211_netdev_notifier_call() which bypasses
the added wireless_nlevent_flush() (added upstream by commit 6784c7db8d43 "cfg80211: change return value of notifier function")
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Beniamino reported that he was getting an RTM_NEWLINK message for a
given interface, after the RTM_DELLINK for it. It turns out that the
message is a wireless extensions message, which was sent because the
interface had been connected and disconnection while it was deleted
caused a wext message.
For its netlink messages, wext uses RTM_NEWLINK, but the message is
without all the regular rtnetlink attributes, so "ip monitor link"
prints just rudimentary information:
5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default
link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
Deleted 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
5: wlan1: <BROADCAST,MULTICAST,UP>
link/ether
(from my hwsim reproduction)
This can cause userspace to get confused since it doesn't expect an
RTM_NEWLINK message after RTM_DELLINK.
The reason for this is that wext schedules a worker to send out the
messages, and the scheduling delay can cause the messages to get out
to userspace in different order.
To fix this, have wext register a netdevice notifier and flush out
any pending messages when netdevice state changes. This fixes any
ordering whenever the original message wasn't sent by a notifier
itself.
Reported-by: Beniamino Galvani <bgalvani@redhat.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Ben Hutchings [Sun, 6 Mar 2016 19:52:46 +0000 (19:52 +0000)]
crypto: {blk,giv}cipher: Set has_setkey
Commit a1383cd86a06 ("crypto: skcipher - Add crypto_skcipher_has_setkey")
was incorrectly backported to the 3.2.y and 3.16.y stable branches.
We need to set ablkcipher_tfm::has_setkey in the
crypto_init_blkcipher_ops_async() and crypto_init_givcipher_ops()
functions as well as crypto_init_ablkcipher_ops().
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Mike Galbraith [Wed, 17 Feb 2016 03:02:59 +0000 (04:02 +0100)]
sched: fix __sched_setscheduler() vs load balancing race
__sched_setscheduler() may release rq->lock in pull_rt_task() as a task is
being changed rt -> fair class. load balancing may sneak in, move the task
behind __sched_setscheduler()'s back, which explodes in switched_to_fair()
when the passed but no longer valid rq is used. Tell can_migrate_task() to
say no if ->pi_lock is held.
@stable: Kernels that predate SCHED_DEADLINE can use this simple (and tested)
check in lieu of backport of the full 18 patch mainline treatment.
Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
[bwh: Backported to 3.2:
- Adjust numbering in the comment
- Adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Willy Tarreau <w@1wt.eu>
Ben Hutchings [Sat, 13 Feb 2016 02:34:52 +0000 (02:34 +0000)]
pipe: Fix buffer offset after partially failed read
Quoting the RHEL advisory:
> It was found that the fix for CVE-2015-1805 incorrectly kept buffer
> offset and buffer length in sync on a failed atomic read, potentially
> resulting in a pipe buffer state corruption. A local, unprivileged user
> could use this flaw to crash the system or leak kernel memory to user
> space. (CVE-2016-0774, Moderate)
The same flawed fix was applied to stable branches from 2.6.32.y to
3.14.y inclusive, and I was able to reproduce the issue on 3.2.y.
We need to give pipe_iov_copy_to_user() a separate offset variable
and only update the buffer offset if it succeeds.
References: https://rhn.redhat.com/errata/RHSA-2016-0103.html Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On no-so-small systems, it is possible for a single process to cause an
OOM condition by filling large pipes with data that are never read. A
typical process filling 4000 pipes with 1 MB of data will use 4 GB of
memory. On small systems it may be tricky to set the pipe max size to
prevent this from happening.
This patch makes it possible to enforce a per-user soft limit above
which new pipes will be limited to a single page, effectively limiting
them to 4 kB each, as well as a hard limit above which no new pipes may
be created for this user. This has the effect of protecting the system
against memory abuse without hurting other users, and still allowing
pipes to work correctly though with less data at once.
The limit are controlled by two new sysctls : pipe-user-pages-soft, and
pipe-user-pages-hard. Both may be disabled by setting them to zero. The
default soft limit allows the default number of FDs per process (1024)
to create pipes of the default size (64kB), thus reaching a limit of 64MB
before starting to create only smaller pipes. With 256 processes limited
to 1024 FDs each, this results in 1024*64kB + (256*1024 - 1024) * 4kB =
1084 MB of memory allocated for a user. The hard limit is disabled by
default to avoid breaking existing applications that make intensive use
of pipes (eg: for splicing).
The commit referenced in the Fixes tag incorrectly accounted the number
of in-flight fds over a unix domain socket to the original opener
of the file-descriptor. This allows another process to arbitrary
deplete the original file-openers resource limit for the maximum of
open files. Instead the sending processes and its struct cred should
be credited.
To do so, we add a reference counted struct user_struct pointer to the
scm_fp_list and use it to account for the number of inflight unix fds.
Fixes: 712f4aad406bb1 ("unix: properly account for FDs passed over unix sockets") Reported-by: David Herrmann <dh.herrmann@gmail.com> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It is possible for a process to allocate and accumulate far more FDs than
the process' limit by sending them over a unix socket then closing them
to keep the process' fd count low.
This change addresses this problem by keeping track of the number of FDs
in flight per user and preventing non-privileged processes from having
more FDs in flight than their configured FD limit.
Reported-by: socketpair@gmail.com Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Mitigates: CVE-2013-4312 (Linux 2.0+) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
[carnil: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The 'umidi' object will be free'd on the error path by snd_usbmidi_free()
when tearing down the rawmidi interface. So we shouldn't try to free it
in snd_usbmidi_create() after having registered the rawmidi interface.
Found by KASAN.
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The value of ctx->pos in the last readdir call is supposed to be set to
INT_MAX due to 32bit compatibility, unless 'pos' is intentially set to a
larger value, then it's LLONG_MAX.
There's a report from PaX SIZE_OVERFLOW plugin that "ctx->pos++"
overflows (https://forums.grsecurity.net/viewtopic.php?f=1&t=4284), on a
64bit arch, where the value is 0x7fffffffffffffff ie. LLONG_MAX before
the increment.
We can get to that situation like that:
* emit all regular readdir entries
* still in the same call to readdir, bump the last pos to INT_MAX
* next call to readdir will not emit any entries, but will reach the
bump code again, finds pos to be INT_MAX and sets it to LLONG_MAX
Normally this is not a problem, but if we call readdir again, we'll find
'pos' set to LLONG_MAX and the unconditional increment will overflow.
The report from Victor at
(http://thread.gmane.org/gmane.comp.file-systems.btrfs/49500) with debugging
print shows that pattern:
The jump from 7fffffff to 7fffffffffffffff happens when new dir entries
are not yet synced and are processed from the delayed list. Then the code
could go to the bump section again even though it might not emit any new
dir entries from the delayed list.
The fix avoids entering the "bump" section again once we've finished
emitting the entries, both for synced and delayed entries.
References: https://forums.grsecurity.net/viewtopic.php?f=1&t=4284 Reported-by: Victor <services@swwu.com> Signed-off-by: David Sterba <dsterba@suse.com> Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com> Signed-off-by: Chris Mason <clm@fb.com>
[bwh: Backported to 3.2:
- s/ctx->pos/filp->f_pos/
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Since the dawn of time the ICST code has only supported divide
by one or hang in an eternal loop. Luckily we were always dividing
by one because the reference frequency for the systems using
the ICSTs is 24MHz and the [min,max] values for the PLL input
if [10,320] MHz for ICST307 and [6,200] for ICST525, so the loop
will always terminate immediately without assigning any divisor
for the reference frequency.
But for the code to make sense, let's insert the missing i++
Reported-by: David Binderman <dcb314@hotmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
snd_timer_user_read() has a potential race among parallel reads, as
qhead and qused are updated outside the critical section due to
copy_to_user() calls. Move them into the critical section, and also
sanitize the relevant code a bit.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: there's no check for tu->connected to fix up] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A slave timer element also unlinks at snd_timer_stop() but it takes
only slave_active_lock. When a slave is assigned to a master,
however, this may become a race against the master's interrupt
handling, eventually resulting in a list corruption. The actual bug
could be seen with a syzkaller fuzzer test case in BugLink below.
As a fix, we need to take timeri->timer->lock when timer isn't NULL,
i.e. assigned to a master, while the assignment to a master itself is
protected by slave_active_lock.
Commit ed5a377d87dc ("sctp: translate host order to network order when
setting a hmacid") corrected the hmacid byte-order when setting a hmacid.
but the same issue also exists on getting a hmacid.
We fix it by changing hmacids to host order when users get them with
getsockopt.
Fixes: Commit ed5a377d87dc ("sctp: translate host order to network order when setting a hmacid") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When trying to set the ICST 307 clock to 25174000 Hz I ran into
this arithmetic error: the icst_hz_to_vco() correctly figure out
DIVIDE=2, RDW=100 and VDW=99 yielding a frequency of 25174000 Hz out of the VCO. (I replicated the icst_hz() function
in a spreadsheet to verify this.)
However, when I called icst_hz() on these VCO settings it would
instead return 4122709 Hz. This causes an error in the common
clock driver for ICST as the common clock framework will call
.round_rate() on the clock which will utilize icst_hz_to_vco()
followed by icst_hz() suggesting the erroneous frequency, and
then the clock gets set to this.
The error did not manifest in the old clock framework since
this high frequency was only used by the CLCD, which calls
clk_set_rate() without first calling clk_round_rate() and since
the old clock framework would not call clk_round_rate() before
setting the frequency, the correct values propagated into
the VCO.
After some experimenting I figured out that it was due to a simple
arithmetic overflow: the divisor for 24Mhz reference frequency
as reference becomes 24000000*2*(99+8)=0x132212400 and the "1"
in bit 32 overflows and is lost.
But introducing an explicit 64-by-32 bit do_div() and casting
the divisor into (u64) we get the right frequency back, and the
right frequency gets set.
Tested on the ARM Versatile.
Cc: linux-clk@vger.kernel.org Cc: Pawel Moll <pawel.moll@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In snd_timer_notify1(), the wrong timer instance was passed for slave
ccallback function. This leads to the access to the wrong data when
an incompatible master is handled (e.g. the master is the sequencer
timer and the slave is a user timer), as spotted by syzkaller fuzzer.
Currently the selected timer backend is referred at any moment from
the running PCM callbacks. When the backend is switched, it's
possible to lead to inconsistency from the running backend. This was
pointed by syzkaller fuzzer, and the commit [7ee96216c31a: ALSA:
dummy: Disable switching timer backend via sysfs] disabled the dynamic
switching for avoiding the crash.
This patch improves the handling of timer backend switching. It keeps
the reference to the selected backend during the whole operation of an
opened stream so that it won't be changed by other streams.
Together with this change, the hrtimer parameter is reenabled as
writable now.
NOTE: this patch also turned out to fix the still remaining race.
Namely, ops was still replaced dynamically at dummy_pcm_open:
static int dummy_pcm_open(struct snd_pcm_substream *substream)
{
....
dummy->timer_ops = &dummy_systimer_ops;
if (hrtimer)
dummy->timer_ops = &dummy_hrtimer_ops;
Since dummy->timer_ops is common among all streams, and when the
replacement happens during accesses of other streams, it may lead to a
crash. This was actually triggered by syzkaller fuzzer and KASAN.
This patch rewrites the code not to use the ops shared by all streams
any longer, too.
The starting node for a klist iteration is often passed in from
somewhere way above the klist infrastructure, meaning there's no
guarantee the node is still on the list. We've seen this in SCSI where
we use bus_find_device() to iterate through a list of devices. In the
face of heavy hotplug activity, the last device returned by
bus_find_device() can be removed before the next call. This leads to
Dec 3 13:22:02 localhost kernel: WARNING: CPU: 2 PID: 28073 at include/linux/kref.h:47 klist_iter_init_node+0x3d/0x50()
Dec 3 13:22:02 localhost kernel: Modules linked in: scsi_debug x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel joydev iTCO_wdt dcdbas ipmi_devintf acpi_power_meter iTCO_vendor_support ipmi_si imsghandler pcspkr wmi acpi_cpufreq tpm_tis tpm shpchp lpc_ich mfd_core nfsd nfs_acl lockd grace sunrpc tg3 ptp pps_core
Dec 3 13:22:02 localhost kernel: CPU: 2 PID: 28073 Comm: cat Not tainted 4.4.0-rc1+ #2
Dec 3 13:22:02 localhost kernel: Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
Dec 3 13:22:02 localhost kernel: ffffffff81a20e77ffff880613acfd18ffffffff81321eef0000000000000000
Dec 3 13:22:02 localhost kernel: ffff880613acfd50ffffffff8107ca52ffff88061176b1980000000000000000
Dec 3 13:22:02 localhost kernel: ffffffff814542b0ffff880610cfb100ffff88061176b198ffff880613acfd60
Dec 3 13:22:02 localhost kernel: Call Trace:
Dec 3 13:22:02 localhost kernel: [<ffffffff81321eef>] dump_stack+0x44/0x55
Dec 3 13:22:02 localhost kernel: [<ffffffff8107ca52>] warn_slowpath_common+0x82/0xc0
Dec 3 13:22:02 localhost kernel: [<ffffffff814542b0>] ? proc_scsi_show+0x20/0x20
Dec 3 13:22:02 localhost kernel: [<ffffffff8107cb4a>] warn_slowpath_null+0x1a/0x20
Dec 3 13:22:02 localhost kernel: [<ffffffff8167225d>] klist_iter_init_node+0x3d/0x50
Dec 3 13:22:02 localhost kernel: [<ffffffff81421d41>] bus_find_device+0x51/0xb0
Dec 3 13:22:02 localhost kernel: [<ffffffff814545ad>] scsi_seq_next+0x2d/0x40
[...]
And an eventual crash. It can actually occur in any hotplug system
which has a device finder and a starting device.
We can fix this globally by making sure the starting node for
klist_iter_init_node() is actually a member of the list before using it
(and by starting from the beginning if it isn't).
Reported-by: Ewan D. Milne <emilne@redhat.com> Tested-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Any access to non-constant bits of the private context must be
done under the socket lock, in particular, this includes ctx->req.
This patch moves such accesses under the lock, and fetches the
tfm from the parent socket which is guaranteed to be constant,
rather than from ctx->req.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2:
- Drop changes to skcipher_recvmsg_async
- s/skcipher/ablkcipher/ in many places
- s/skc->skcipher/skc->base/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We miss to take the crypto_alg_sem semaphore when traversing the
crypto_alg_list for CRYPTO_MSG_GETALG dumps. This allows a race with
crypto_unregister_alg() removing algorithms from the list while we're
still traversing it, thereby leading to a use-after-free as show below:
To trigger the race run the following loops simultaneously for a while:
$ while : ; do modprobe aesni-intel; rmmod aesni-intel; done
$ while : ; do crconf show all > /dev/null; done
Fix the race by taking the crypto_alg_sem read lock, thereby preventing
crypto_unregister_alg() from modifying the algorithm list during the
dump.
This bug has been detected by the PaX memory sanitize feature.
Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: PaX Team <pageexec@freemail.hu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When recovery master down, dlm_do_local_recovery_cleanup() only remove
the $RECOVERY lock owned by dead node, but do not clear the refmap bit.
Which will make umount thread falling in dead loop migrating $RECOVERY
to the dead node.
Signed-off-by: xuejiufei <xuejiufei@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Jan Stancek has reported that system occasionally hanging after "oom01"
testcase from LTP triggers OOM. Guessing from a result that there is a
kworker thread doing memory allocation and the values between "Node 0
Normal free:" and "Node 0 Normal:" differs when hanging, vmstat is not
up-to-date for some reason.
According to commit 373ccbe59270 ("mm, vmstat: allow WQ concurrency to
discover memory reclaim doesn't make any progress"), it meant to force
the kworker thread to take a short sleep, but it by error used
schedule_timeout(1). We missed that schedule_timeout() in state
TASK_RUNNING doesn't do anything.
Fix it by using schedule_timeout_uninterruptible(1) which forces the
kworker thread to take a short sleep in order to make sure that vmstat
is up-to-date.
Fixes: 373ccbe59270 ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Jan Stancek <jstancek@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tejun Heo <tj@kernel.org> Cc: Cristopher Lameter <clameter@sgi.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Arkadiusz Miskiewicz <arekm@maven.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If MODE SELECT returns with sense '05/91/36' (command lock violation)
it should always be retried without counting the number of retries.
During an HBA upgrade or similar circumstances one might see a flood
of MODE SELECT command from various HBAs, which will easily trigger
the sense code and exceed the retry count.
Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In ALSA timer core, the active timer instance is managed in
active_list linked list. Each element is added / removed dynamically
at timer start, stop and in timer interrupt. The problem is that
snd_timer_interrupt() has a thinko and leaves the element in
active_list when it's the last opened element. This eventually leads
to list corruption or use-after-free error.
This hasn't been revealed because we used to delete the list forcibly
in snd_timer_stop() in the past. However, the recent fix avoids the
double-stop behavior (in commit [f784beb75ce8: ALSA: timer: Fix link
corruption due to double start or stop]), and this leak hits reality.
This patch fixes the link management in snd_timer_interrupt(). Now it
simply unlinks no matter which stream is.
The tda1004x was updating the properties cache before locking.
If the device is not locked, the data at the registers are just
random values with no real meaning.
This caused the driver to fail with libdvbv5, as such library
calls GET_PROPERTY from time to time, in order to return the
DVB stats.
Tested with a saa7134 card 78:
ASUSTeK P7131 Dual, vendor PCI ID: 1043:4862
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
xhci driver frees data for all devices, both usb2 and and usb3 the
first time usb_remove_hcd() is called, including td_list and and xhci_ring
structures.
When usb_remove_hcd() is called a second time for the second xhci bus it
will try to dequeue all pending urbs, and touches td_list which is already
freed for that endpoint.
Reported-by: Joe Lawrence <joe.lawrence@stratus.com> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This reverts commit e210c422b6fd ("xhci: don't finish a TD if we get a
short transfer event mid TD")
Turns out that most host controllers do not follow the xHCI specs and never
send the second event for the last TRB in the TD if there was a short event
mid-TD.
Returning the URB directly after the first short-transfer event is far
better than never returning the URB. (class drivers usually timeout
after 30sec). For the hosts that do send the second event we will go
back to treating it as misplaced event and print an error message for it.
The origial patch was sent to stable kernels and needs to be reverted from
there as well
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The port subscription code uses double mutex locks for source and
destination ports, and this may become racy once when wrongly set up.
It leads to lockdep warning splat, typically triggered by fuzzer like
syzkaller, although the actual deadlock hasn't been seen, so far.
This patch simplifies the handling by reducing to two single locks, so
that no lockdep warning will be trigger any longer.
By splitting to two actions, a still-in-progress element shall be
added in one list while handling another. For ignoring this element,
a new check is added in deliver_to_subscribers().
Along with it, the code to add/remove the subscribers list element was
cleaned up and refactored.
The rawmidi read and write functions manage runtime stream status
such as runtime->appl_ptr and runtime->avail. These point where to
copy the new data and how many bytes have been copied (or to be
read). The problem is that rawmidi read/write call copy_from_user()
or copy_to_user(), and the runtime spinlock is temporarily unlocked
and relocked while copying user-space. Since the current code
advances and updates the runtime status after the spin unlock/relock,
the copy and the update may be asynchronous, and eventually
runtime->avail might go to a negative value when many concurrent
accesses are done. This may lead to memory corruption in the end.
For fixing this race, in this patch, the status update code is
performed in the same lock before the temporary unlock. Also, the
spinlock is now taken more widely in snd_rawmidi_kernel_read1() for
protecting more properly during the whole operation.
Also a similar warning is found but in another path:
Call Trace:
[< inline >] __dump_stack lib/dump_stack.c:15
[<ffffffff82be2c0d>] dump_stack+0x6f/0xa2 lib/dump_stack.c:50
[<ffffffff81355139>] warn_slowpath_common+0xd9/0x140 kernel/panic.c:482
[<ffffffff81355369>] warn_slowpath_null+0x29/0x30 kernel/panic.c:515
[<ffffffff8527e69a>] rawmidi_transmit_ack+0x24a/0x3b0 sound/core/rawmidi.c:1133
[<ffffffff8527e851>] snd_rawmidi_transmit_ack+0x51/0x80 sound/core/rawmidi.c:1163
[<ffffffff852d9046>] snd_virmidi_output_trigger+0x2b6/0x570 sound/core/seq/seq_virmidi.c:185
[< inline >] snd_rawmidi_output_trigger sound/core/rawmidi.c:150
[<ffffffff85285a0b>] snd_rawmidi_kernel_write1+0x4bb/0x760 sound/core/rawmidi.c:1252
[<ffffffff85287b73>] snd_rawmidi_write+0x543/0xb30 sound/core/rawmidi.c:1302
[<ffffffff817ba5f3>] __vfs_write+0x113/0x480 fs/read_write.c:528
[<ffffffff817bc087>] vfs_write+0x167/0x4a0 fs/read_write.c:577
[< inline >] SYSC_write fs/read_write.c:624
[<ffffffff817bf371>] SyS_write+0x111/0x220 fs/read_write.c:616
[<ffffffff86660276>] entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185
In the former case, the reason is that virmidi has an open code
calling snd_rawmidi_transmit_ack() with the value calculated outside
the spinlock. We may use snd_rawmidi_transmit() in a loop just for
consuming the input data, but even there, there is a race between
snd_rawmidi_transmit_peek() and snd_rawmidi_tranmit_ack().
Similarly in the latter case, it calls snd_rawmidi_transmit_peek() and
snd_rawmidi_tranmit_ack() separately without protection, so they are
racy as well.
The patch tries to address these issues by the following ways:
- Introduce the unlocked versions of snd_rawmidi_transmit_peek() and
snd_rawmidi_transmit_ack() to be called inside the explicit lock.
- Rewrite snd_rawmidi_transmit() to be race-free (the former case).
- Make the split calls (the latter case) protected in the rawmidi spin
lock.
The bulk of ATA host state machine is implemented by
ata_sff_hsm_move(). The function is called from either the interrupt
handler or, if polling, a work item. Unlike from the interrupt path,
the polling path calls the function without holding the host lock and
ata_sff_hsm_move() selectively grabs the lock.
This is completely broken. If an IRQ triggers while polling is in
progress, the two can easily race and end up accessing the hardware
and updating state machine state at the same time. This can put the
state machine in an illegal state and lead to a crash like the
following.
Fix it by ensuring that the polling path is holding the host lock
before entering ata_sff_hsm_move() so that all hardware accesses and
state updates are performed under the host lock.
Although ALSA timer code got hardening for races, it still causes
use-after-free error. This is however rather a corrupted linked list,
not actually the concurrent accesses. Namely, when timer start is
triggered twice, list_add_tail() is called twice, too. This ends
up with the link corruption and triggers KASAN error.
The simplest fix would be replacing list_add_tail() with
list_move_tail(), but fundamentally it's the problem that we don't
check the double start/stop correctly. So, the right fix here is to
add the proper checks to snd_timer_start() and snd_timer_stop() (and
their variants).
ALSA sequencer may open/close and control ALSA timer instance
dynamically either via sequencer events or direct ioctls. These are
done mostly asynchronously, and it may call still some timer action
like snd_timer_start() while another is calling snd_timer_close().
Since the instance gets removed by snd_timer_close(), it may lead to
a use-after-free.
This patch tries to address such a race by protecting each
snd_timer_*() call via the existing spinlock and also by avoiding the
access to timer during close call.
There are potential deadlocks in PCM OSS emulation code while
accessing read/write and mmap concurrently. This comes from the
infamous mmap_sem usage in copy_from/to_user(). Namely,
NULL user-space buffer can be passed even in a normal path, thus it's
not good to spew a kernel warning with stack trace at each time.
Just drop snd_BUG_ON() macro usage there.