commit 10dce8af34 upstream.
Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.
This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d0 ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.
The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.
However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655 -
is doing so irregardless of whether a file is seekable or not.
See
https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/https://lwn.net/Articles/180387https://lwn.net/Articles/180396
for historic context.
The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:
kernel/power/user.c snapshot_read
fs/debugfs/file.c u32_array_read
fs/fuse/control.c fuse_conn_waiting_read + ...
drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read
arch/s390/hypfs/inode.c hypfs_read_iter
...
Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.
Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()
In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.
FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f7 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:
See
https://github.com/libfuse/osspdhttps://lwn.net/Articles/308445https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510
Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216
I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:
https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169
Let's fix this regression. The plan is:
1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
doing so would break many in-kernel nonseekable_open users which
actually use ppos in read/write handlers.
2. Add stream_open() to kernel to open stream-like non-seekable file
descriptors. Read and write on such file descriptors would never use
nor change ppos. And with that property on stream-like files read and
write will be running without taking f_pos lock - i.e. read and write
could be running simultaneously.
3. With semantic patch search and convert to stream_open all in-kernel
nonseekable_open users for which read and write actually do not
depend on ppos and where there is no other methods in file_operations
which assume @offset access.
4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
steam_open if that bit is present in filesystem open reply.
It was tempting to change fs/fuse/ open handler to use stream_open
instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and
write handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3Dhttps://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
from v3.14+ (the kernel where 9c225f2655 first appeared).
This will allow to patch OSSPD and other FUSE filesystems that
provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
in their open handler and this way avoid the deadlock on all kernel
versions. This should work because fs/fuse/ ignores unknown open
flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel
that is not aware of FOPEN_STREAM will be < v3.14 where just
FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
write deadlock.
This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.
Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.
The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e4bf63482c upstream.
Most, if not all, Quectel devices use dynamic interface numbers, and
users are able to change the USB configuration at will. Matching on for
example interface number is therefore not possible.
Instead, the QMI device can be identified by looking at the interface
class, subclass and protocol (all 0xff), as well as the number of
endpoints. The reason we need to look at the number of endpoints, is
that the diagnostic port interface has the same class, subclass and
protocol as QMI. However, the diagnostic port only has two endpoints,
while QMI has three.
Until now, we have identified the QMI device by combining a match on
class, subclass and protocol, with a call to the function
quectel_diag_detect(). In quectel_diag_detect(), we check if the number
of endpoints matches for known Quectel vendor/product ids.
Adding new vendor/product ids to quectel_diag_detect() is not a good
long-term solution. This commit replaces the function with a quirk, and
applies the quirk to affected Quectel devices that I have been able to
test the change with (EP06, EM12 and EC25). If the quirk is set and the
number of endpoints equal two, we return from qmi_wwan_probe() with
-ENODEV.
[In order for this patch to apply cleanly to 4.14, two minor changes had
to be made. First, the original work-around (quectel_diag_detect()) for
the dynamic interface numbers was never backported to 4.14, so there is
no need to remove this code. Second, support for the EM12 was also not
backported to 4.14. Since supporting EM12 is a trivial change (just
another VID/PID match), and the match for EM12 is changed by this patch,
I chose to not submit adding EM12-support as a separate patch.]
Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4cdd17ba1d upstream.
We need to compute the uart state only on the first open. This is
usually what is done in the ->install hook. serial_core used to do this
in ->open on every open. So move it to ->install.
As a side effect, it ensures the state is set properly in the window
after tty_init_dev is called, but before uart_open. This fixes a bunch
of races between tty_open and flush_to_ldisc we were dealing with
recently.
One of such bugs was attempted to fix in commit fedb576064 (serial:
fix race between flush_to_ldisc and tty_open), but it only took care of
a couple of functions (uart_start and uart_unthrottle). I was able to
reproduce the crash on a SLE system, but in uart_write_room which is
also called from flush_to_ldisc via process_echoes. I was *unable* to
reproduce the bug locally. It is due to having this patch in my queue
since 2012!
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 5 Comm: kworker/u4:0 Tainted: G L 4.12.14-396-default #1 SLE15-SP1 (unreleased)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
Workqueue: events_unbound flush_to_ldisc
task: ffff8800427d8040 task.stack: ffff8800427f0000
RIP: 0010:uart_write_room+0xc4/0x590
RSP: 0018:ffff8800427f7088 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 000000000000002f RSI: 00000000000000ee RDI: ffff88003888bd90
RBP: ffffffffb9545850 R08: 0000000000000001 R09: 0000000000000400
R10: ffff8800427d825c R11: 000000000000006e R12: 1ffff100084fee12
R13: ffffc900004c5000 R14: ffff88003888bb28 R15: 0000000000000178
FS: 0000000000000000(0000) GS:ffff880043300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561da0794148 CR3: 000000000ebf4000 CR4: 00000000000006e0
Call Trace:
tty_write_room+0x6d/0xc0
__process_echoes+0x55/0x870
n_tty_receive_buf_common+0x105e/0x26d0
tty_ldisc_receive_buf+0xb7/0x1c0
tty_port_default_receive_buf+0x107/0x180
flush_to_ldisc+0x35d/0x5c0
...
0 in rbx means tty->driver_data is NULL in uart_write_room. 0x178 is
tried to be dereferenced (0x178 >> 3 is 0x2f in rdx) at
uart_write_room+0xc4. 0x178 is exactly (struct uart_state *)NULL->refcount
used in uart_port_lock from uart_write_room.
So revert the upstream commit here as my local patch should fix the
whole family.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Li RongQing <lirongqing@baidu.com>
Cc: Wang Li <wangli39@baidu.com>
Cc: Zhang Yu <zhangyu31@baidu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b30a43ac71 upstream.
There was a nouveau DDX that relied on legacy context ioctls to work,
but we fixed it years ago, give distros that have a modern DDX the
option to break the uAPI and close the mess of holes that legacy
context support is.
Full context of the story:
commit 0e975980d4
Author: Peter Antoine <peter.antoine@intel.com>
Date: Tue Jun 23 08:18:49 2015 +0100
drm: Turn off Legacy Context Functions
The context functions are not used by the i915 driver and should not
be used by modeset drivers. These driver functions contain several bugs
and security holes. This change makes these functions optional can be
turned on by a setting, they are turned off by default for modeset
driver with the exception of the nouvea driver that may require them with
an old version of libdrm.
The previous attempt was
commit 7c510133d9
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Aug 8 15:41:21 2013 +0200
drm: mark context support as a legacy subsystem
but this had to be reverted
commit c21eb21cb5
Author: Dave Airlie <airlied@redhat.com>
Date: Fri Sep 20 08:32:59 2013 +1000
Revert "drm: mark context support as a legacy subsystem"
v2: remove returns from void function, and formatting (Daniel Vetter)
v3:
- s/Nova/nouveau/ in the commit message, and add references to the
previous attempts
- drop the part touching the drm hw lock, that should be a separate
patch.
Signed-off-by: Peter Antoine <peter.antoine@intel.com> (v2)
Cc: Peter Antoine <peter.antoine@intel.com> (v2)
Reviewed-by: Peter Antoine <peter.antoine@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
v2: move DRM_VM dependency into legacy config.
v3: fix missing dep (kbuild robot)
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bd17cc5a20 upstream.
The limit here is supposed to be how much of the page is left, but it's
just using PAGE_SIZE as the limit.
The other thing to remember is that snprintf() returns the number of
bytes which would have been copied if we had had enough room. So that
means that if we run out of space then this code would end up passing a
negative value as the limit and the kernel would print an error message.
I have change the code to use scnprintf() which returns the number of
bytes that were successfully printed (not counting the NUL terminator).
Fixes: c92316bf8e ("test_firmware: add batched firmware tests")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 110080cea0 upstream.
There are a couple potential integer overflows here.
round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE);
The first thing is that the "m->size + (...)" addition could overflow,
and the second is that round_up() overflows to zero if the result is
within PAGE_SIZE of the type max.
In this code, the "m->size" variable is an u64 but we're saving the
result in "map_size" which is an unsigned long and genwqe_user_vmap()
takes an unsigned long as well. So I have used ULONG_MAX as the upper
bound. From a practical perspective unsigned long is fine/better than
trying to change all the types to u64.
Fixes: eaf4722d46 ("GenWQE Character device and DDCB queue")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 9547d81ac3 which is
commit a1e8783db8 upstream.
Petr writes:
Karl has reported to me today, that he's experiencing weird
reboot hang on his devices with 4.9.180 kernel and that he has
bisected it down to my backported patch.
I would like to kindly ask you for removal of this patch. This
patch should be reverted from all stable kernels up to 5.1,
because perf counters were not broken on those kernels, and this
patch won't work on the ath79 legacy IRQ code anyway, it needs
new irqchip driver which was enabled on ath79 with commit
51fa4f8912 ("MIPS: ath79: drop legacy IRQ code").
Reported-by: Petr Štetiar <ynezz@true.cz>
Cc: Kevin 'ldir' Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Cc: John Crispin <john@phrozen.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e4f2d1af71 upstream.
The pistachio platform uses the U-Boot bootloader & generally boots a
kernel in the uImage format. As such it's useful to build one when
building the kernel, but to do so currently requires the user to
manually specify a uImage target on the make command line.
Make uImage.gz the pistachio platform's default build target, so that
the default is to build a kernel image that we can actually boot on a
board such as the MIPS Creator Ci40.
Marked for stable backport as far as v4.1 where pistachio support was
introduced. This is primarily useful for CI systems such as kernelci.org
which will benefit from us building a suitable image which can then be
booted as part of automated testing, extending our test coverage to the
affected stable branches.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
URL: https://groups.io/g/kernelci/message/388
Cc: stable@vger.kernel.org # v4.1+
Cc: linux-mips@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 074a1e1167 upstream.
The virt_addr_valid() function is meant to return true iff
virt_to_page() will return a valid struct page reference. This is true
iff the address provided is found within the unmapped address range
between PAGE_OFFSET & MAP_BASE, but we don't currently check for that
condition. Instead we simply mask the address to obtain what will be a
physical address if the virtual address is indeed in the desired range,
shift it to form a PFN & then call pfn_valid(). This can incorrectly
return true if called with a virtual address which, after masking,
happens to form a physical address corresponding to a valid PFN.
For example we may vmalloc an address in the kernel mapped region
starting a MAP_BASE & obtain the virtual address:
addr = 0xc000000000002000
When masked by virt_to_phys(), which uses __pa() & in turn CPHYSADDR(),
we obtain the following (bogus) physical address:
addr = 0x2000
In a common system with PHYS_OFFSET=0 this will correspond to a valid
struct page which should really be accessed by virtual address
PAGE_OFFSET+0x2000, causing virt_addr_valid() to incorrectly return 1
indicating that the original address corresponds to a struct page.
This is equivalent to the ARM64 change made in commit ca219452c6
("arm64: Correctly bounds check virt_addr_valid").
This fixes fallout when hardened usercopy is enabled caused by the
related commit 517e1fbeb6 ("mm/usercopy: Drop extra
is_vmalloc_or_module() check") which removed a check for the vmalloc
range that was present from the introduction of the hardened usercopy
feature.
Signed-off-by: Paul Burton <paul.burton@mips.com>
References: ca219452c6 ("arm64: Correctly bounds check virt_addr_valid")
References: 517e1fbeb6 ("mm/usercopy: Drop extra is_vmalloc_or_module() check")
Reported-by: Julien Cristau <jcristau@debian.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: YunQiang Su <ysu@wavecomp.com>
URL: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=929366
Cc: stable@vger.kernel.org # v4.12+
Cc: linux-mips@vger.kernel.org
Cc: Yunqiang Su <ysu@wavecomp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 49b8095867 upstream.
This driver does not support reading more than 255 bytes at once because
the register for storing the number of bytes to read is only 8 bits. Add
a max_read_len quirk to enforce this.
This was found when using this driver with the SFP driver, which was
previously reading all 256 bytes in the SFP EEPROM in one transaction.
This caused a bunch of hard-to-debug errors in the xiic driver since the
driver/logic was treating the number of bytes to read as zero.
Rejecting transactions that aren't supported at least allows the problem
to be diagnosed more easily.
Signed-off-by: Robert Hancock <hancock@sedsystems.ca>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ec527c3180 upstream.
As explained in
0cc3cd2165 ("cpu/hotplug: Boot HT siblings at least once")
we always, no matter what, have to bring up x86 HT siblings during boot at
least once in order to avoid first MCE bringing the system to its knees.
That means that whenever 'nosmt' is supplied on the kernel command-line,
all the HT siblings are as a result sitting in mwait or cpudile after
going through the online-offline cycle at least once.
This causes a serious issue though when a kernel, which saw 'nosmt' on its
commandline, is going to perform resume from hibernation: if the resume
from the hibernated image is successful, cr3 is flipped in order to point
to the address space of the kernel that is being resumed, which in turn
means that all the HT siblings are all of a sudden mwaiting on address
which is no longer valid.
That results in triple fault shortly after cr3 is switched, and machine
reboots.
Fix this by always waking up all the SMT siblings before initiating the
'restore from hibernation' process; this guarantees that all the HT
siblings will be properly carried over to the resumed kernel waiting in
resume_play_dead(), and acted upon accordingly afterwards, based on the
target kernel configuration.
Symmetricaly, the resumed kernel has to push the SMT siblings to mwait
again in case it has SMT disabled; this means it has to online all
the siblings when resuming (so that they come out of hlt) and offline
them again to let them reach mwait.
Cc: 4.19+ <stable@vger.kernel.org> # v4.19+
Debugged-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 0cc3cd2165 ("cpu/hotplug: Boot HT siblings at least once")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8880fa32c5 upstream.
The ram pstore backend has always had the crash dumper frontend enabled
unconditionally. However, it was possible to effectively disable it
by setting a record_size=0. All the machinery would run (storing dumps
to the temporary crash buffer), but 0 bytes would ultimately get stored
due to there being no przs allocated for dumps. Commit 89d328f637
("pstore/ram: Correctly calculate usable PRZ bytes"), however, assumed
that there would always be at least one allocated dprz for calculating
the size of the temporary crash buffer. This was, of course, not the
case when record_size=0, and would lead to a NULL deref trying to find
the dprz buffer size:
BUG: unable to handle kernel NULL pointer dereference at (null)
...
IP: ramoops_probe+0x285/0x37e (fs/pstore/ram.c:808)
cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size;
Instead, we need to only enable the frontends based on the success of the
prz initialization and only take the needed actions when those zones are
available. (This also fixes a possible error in detecting if the ftrace
frontend should be enabled.)
Reported-and-tested-by: Yaro Slav <yaro330@gmail.com>
Fixes: 89d328f637 ("pstore/ram: Correctly calculate usable PRZ bytes")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ea84b580b9 upstream.
Instead of running with interrupts disabled, use a semaphore. This should
make it easier for backends that may need to sleep (e.g. EFI) when
performing a write:
|BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
|in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum
|Preemption disabled at:
|[<ffffffff99d60512>] pstore_dump+0x72/0x330
|CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45
|Call Trace:
| dump_stack+0x4f/0x6a
| ___might_sleep.cold.91+0xd3/0xe4
| __might_sleep+0x50/0x90
| wait_for_completion+0x32/0x130
| virt_efi_query_variable_info+0x14e/0x160
| efi_query_variable_store+0x51/0x1a0
| efivar_entry_set_safe+0xa3/0x1b0
| efi_pstore_write+0x109/0x140
| pstore_dump+0x11c/0x330
| kmsg_dump+0xa4/0xd0
| oops_exit+0x22/0x30
...
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: 21b3ddd39f ("efi: Don't use spinlocks for efi vars")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b77fa617a2 upstream.
Since the console writer does not use the preallocated crash dump buffer
any more, there is no reason to perform locking around it.
Fixes: 70ad35db33 ("pstore: Convert console write to use ->write_buf")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63923d2c38 upstream.
We only support I/O to kernel space. Using %sr1 to load the coherence
index may be racy unless interrupts are disabled. This patch changes the
code used to load the coherence index to use implicit space register
selection. This saves one instruction and eliminates the race.
Tested on rp3440, c8000 and c3750.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 66be4e66a7 upstream.
Herbert Xu pointed out that commit bb73c52bad ("rcu: Don't disable
preemption for Tiny and Tree RCU readers") was incorrect in making the
preempt_disable/enable() be conditional on CONFIG_PREEMPT_COUNT.
If CONFIG_PREEMPT_COUNT isn't enabled, the preemption enable/disable is
a no-op, but still is a compiler barrier.
And RCU locking still _needs_ that compiler barrier.
It is simply fundamentally not true that RCU locking would be a complete
no-op: we still need to guarantee (for example) that things that can
trap and cause preemption cannot migrate into the RCU locked region.
The way we do that is by making it a barrier.
See for example commit 386afc9114 ("spinlocks and preemption points
need to be at least compiler barriers") from back in 2013 that had
similar issues with spinlocks that become no-ops on UP: they must still
constrain the compiler from moving other operations into the critical
region.
Now, it is true that a lot of RCU operations already use READ_ONCE() and
WRITE_ONCE() (which in practice likely would never be re-ordered wrt
anything remotely interesting), but it is also true that that is not
globally the case, and that it's not even necessarily always possible
(ie bitfields etc).
Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Fixes: bb73c52bad ("rcu: Don't disable preemption for Tiny and Tree RCU readers")
Cc: stable@kernel.org
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4970b42d5c ]
This reverts commit e9919a24d3.
Nathan reported the new behaviour breaks Android, as Android just add
new rules and delete old ones.
If we return 0 without adding dup rules, Android will remove the new
added rules and causing system to soft-reboot.
Fixes: e9919a24d3 ("fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Yaro Slav <yaro330@gmail.com>
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 691306ebd1 as the
patch that this "fixes" is about to be reverted...
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b7999b0772 ]
In Jianlin's testing, netperf was broken with 'Connection reset by peer',
as the cookie check failed in rt6_check() and ip6_dst_check() always
returned NULL.
It's caused by Commit 93531c6743 ("net/ipv6: separate handling of FIB
entries from dst based routes"), where the cookie can be got only when
'c1'(see below) for setting dst_cookie whereas rt6_check() is called
when !'c1' for checking dst_cookie, as we can see in ip6_dst_check().
Since in ip6_dst_check() both rt6_dst_from_check() (c1) and rt6_check()
(!c1) will check the 'from' cookie, this patch is to remove the c1 check
in rt6_get_cookie(), so that the dst_cookie can always be set properly.
c1:
(rt->rt6i_flags & RTF_PCPU || unlikely(!list_empty(&rt->rt6i_uncached)))
Fixes: 93531c6743 ("net/ipv6: separate handling of FIB entries from dst based routes")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 28e74a7cfd ]
Some SFP modules do not like reads longer than 16 bytes, so read the
EEPROM in chunks of 16 bytes at a time. This behaviour is not specified
in the SFP MSAs, which specifies:
"The serial interface uses the 2-wire serial CMOS E2PROM protocol
defined for the ATMEL AT24C01A/02/04 family of components."
and
"As long as the SFP+ receives an acknowledge, it shall serially clock
out sequential data words. The sequence is terminated when the host
responds with a NACK and a STOP instead of an acknowledge."
We must avoid breaking a read across a 16-bit quantity in the diagnostic
page, thankfully all 16-bit quantities in that page are naturally
aligned.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 59e3e4b526 ]
As it was done in commit 8f659a03a0 ("net: ipv4: fix for a race
condition in raw_sendmsg") and commit 20b50d7997 ("net: ipv4: emulate
READ_ONCE() on ->hdrincl bit-field in raw_sendmsg()") for ipv4, copy the
value of inet->hdrincl in a local variable, to avoid introducing a race
condition in the next commit.
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b9aa52c4cb ]
The following code returns EFAULT (Bad address):
s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
setsockopt(s, SOL_IPV6, IPV6_HDRINCL, 1);
sendto(ipv6_icmp6_packet, addr); /* returns -1, errno = EFAULT */
The IPv4 equivalent code works. A workaround is to use IPPROTO_RAW
instead of IPPROTO_ICMPV6.
The failure happens because 2 bytes are eaten from the msghdr by
rawv6_probe_proto_opt() starting from commit 19e3c66b52 ("ipv6
equivalent of "ipv4: Avoid reading user iov twice after
raw_probe_proto_opt""), but at that time it was not a problem because
IPV6_HDRINCL was not yet introduced.
Only eat these 2 bytes if hdrincl == 0.
Fixes: 715f504b11 ("ipv6: add IPV6_HDRINCL option for raw sockets")
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 720f1de402 ]
Currently, the process issuing a "start" command on the pktgen procfs
interface, acquires the pktgen thread lock and never release it, until
all pktgen threads are completed. The above can blocks indefinitely any
other pktgen command and any (even unrelated) netdevice removal - as
the pktgen netdev notifier acquires the same lock.
The issue is demonstrated by the following script, reported by Matteo:
ip -b - <<'EOF'
link add type dummy
link add type veth
link set dummy0 up
EOF
modprobe pktgen
echo reset >/proc/net/pktgen/pgctrl
{
echo rem_device_all
echo add_device dummy0
} >/proc/net/pktgen/kpktgend_0
echo count 0 >/proc/net/pktgen/dummy0
echo start >/proc/net/pktgen/pgctrl &
sleep 1
rmmod veth
Fix the above releasing the thread lock around the sleep call.
Additionally we must prevent racing with forcefull rmmod - as the
thread lock no more protects from them. Instead, acquire a self-reference
before waiting for any thread. As a side effect, running
rmmod pktgen
while some thread is running now fails with "module in use" error,
before this patch such command hanged indefinitely.
Note: the issue predates the commit reported in the fixes tag, but
this fix can't be applied before the mentioned commit.
v1 -> v2:
- no need to check for thread existence after flipping the lock,
pktgen threads are freed only at net exit time
-
Fixes: 6146e6a43b ("[PKTGEN]: Removes thread_{un,}lock() macros.")
Reported-and-tested-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 85cb928787 ]
When the following tests last for several hours, the problem will occur.
Server:
rds-stress -r 1.1.1.16 -D 1M
Client:
rds-stress -r 1.1.1.14 -s 1.1.1.16 -D 1M -T 30
The following will occur.
"
Starting up....
tsks tx/s rx/s tx+rx K/s mbi K/s mbo K/s tx us/c rtt us cpu
%
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
1 0 0 0.00 0.00 0.00 0.00 0.00 -1.00
"
>From vmcore, we can find that clean_list is NULL.
>From the source code, rds_mr_flushd calls rds_ib_mr_pool_flush_worker.
Then rds_ib_mr_pool_flush_worker calls
"
rds_ib_flush_mr_pool(pool, 0, NULL);
"
Then in function
"
int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
int free_all, struct rds_ib_mr **ibmr_ret)
"
ibmr_ret is NULL.
In the source code,
"
...
list_to_llist_nodes(pool, &unmap_list, &clean_nodes, &clean_tail);
if (ibmr_ret)
*ibmr_ret = llist_entry(clean_nodes, struct rds_ib_mr, llnode);
/* more than one entry in llist nodes */
if (clean_nodes->next)
llist_add_batch(clean_nodes->next, clean_tail, &pool->clean_list);
...
"
When ibmr_ret is NULL, llist_entry is not executed. clean_nodes->next
instead of clean_nodes is added in clean_list.
So clean_nodes is discarded. It can not be used again.
The workqueue is executed periodically. So more and more clean_nodes are
discarded. Finally the clean_list is NULL.
Then this problem will occur.
Fixes: 1bc144b625 ("net, rds, Replace xlist in net/rds/xlist.h with llist")
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 135dd9594f ]
Querying EEPROM high pages data for SFP module is currently
not supported by our driver but is still tried, resulting in
invalid FW queries.
Set the EEPROM ethtool data length to 256 for SFP module to
limit the reading for page 0 only and prevent invalid FW queries.
Fixes: 7202da8b7f ("ethtool, net/mlx4_en: Cable info, get_module_info/eeprom ethtool support")
Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4b2a2bfeb3 ]
Commit cd9ff4de01 changed the key for IFF_POINTOPOINT devices to
INADDR_ANY but neigh_xmit which is used for MPLS encapsulations was not
updated to use the altered key. The result is that every packet Tx does
a lookup on the gateway address which does not find an entry, a new one
is created only to find the existing one in the table right before the
insert since arp_constructor was updated to reset the primary key. This
is seen in the allocs and destroys counters:
ip -s -4 ntable show | head -10 | grep alloc
which increase for each packet showing the unnecessary overhread.
Fix by having neigh_xmit use __ipv4_neigh_lookup_noref for NEIGH_ARP_TABLE.
Fixes: cd9ff4de01 ("ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY")
Reported-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0a8dd9f67c ]
syzbot found the following leak in sctp_process_init
BUG: memory leak
unreferenced object 0xffff88810ef68400 (size 1024):
comm "syz-executor273", pid 7046, jiffies 4294945598 (age 28.770s)
hex dump (first 32 bytes):
1d de 28 8d de 0b 1b e3 b5 c2 f9 68 fd 1a 97 25 ..(........h...%
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000a02cebbd>] kmemleak_alloc_recursive include/linux/kmemleak.h:55
[inline]
[<00000000a02cebbd>] slab_post_alloc_hook mm/slab.h:439 [inline]
[<00000000a02cebbd>] slab_alloc mm/slab.c:3326 [inline]
[<00000000a02cebbd>] __do_kmalloc mm/slab.c:3658 [inline]
[<00000000a02cebbd>] __kmalloc_track_caller+0x15d/0x2c0 mm/slab.c:3675
[<000000009e6245e6>] kmemdup+0x27/0x60 mm/util.c:119
[<00000000dfdc5d2d>] kmemdup include/linux/string.h:432 [inline]
[<00000000dfdc5d2d>] sctp_process_init+0xa7e/0xc20
net/sctp/sm_make_chunk.c:2437
[<00000000b58b62f8>] sctp_cmd_process_init net/sctp/sm_sideeffect.c:682
[inline]
[<00000000b58b62f8>] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1384
[inline]
[<00000000b58b62f8>] sctp_side_effects net/sctp/sm_sideeffect.c:1194
[inline]
[<00000000b58b62f8>] sctp_do_sm+0xbdc/0x1d60 net/sctp/sm_sideeffect.c:1165
[<0000000044e11f96>] sctp_assoc_bh_rcv+0x13c/0x200
net/sctp/associola.c:1074
[<00000000ec43804d>] sctp_inq_push+0x7f/0xb0 net/sctp/inqueue.c:95
[<00000000726aa954>] sctp_backlog_rcv+0x5e/0x2a0 net/sctp/input.c:354
[<00000000d9e249a8>] sk_backlog_rcv include/net/sock.h:950 [inline]
[<00000000d9e249a8>] __release_sock+0xab/0x110 net/core/sock.c:2418
[<00000000acae44fa>] release_sock+0x37/0xd0 net/core/sock.c:2934
[<00000000963cc9ae>] sctp_sendmsg+0x2c0/0x990 net/sctp/socket.c:2122
[<00000000a7fc7565>] inet_sendmsg+0x64/0x120 net/ipv4/af_inet.c:802
[<00000000b732cbd3>] sock_sendmsg_nosec net/socket.c:652 [inline]
[<00000000b732cbd3>] sock_sendmsg+0x54/0x70 net/socket.c:671
[<00000000274c57ab>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2292
[<000000008252aedb>] __sys_sendmsg+0x80/0xf0 net/socket.c:2330
[<00000000f7bf23d1>] __do_sys_sendmsg net/socket.c:2339 [inline]
[<00000000f7bf23d1>] __se_sys_sendmsg net/socket.c:2337 [inline]
[<00000000f7bf23d1>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2337
[<00000000a8b4131f>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:3
The problem was that the peer.cookie value points to an skb allocated
area on the first pass through this function, at which point it is
overwritten with a heap allocated value, but in certain cases, where a
COOKIE_ECHO chunk is included in the packet, a second pass through
sctp_process_init is made, where the cookie value is re-allocated,
leaking the first allocation.
Fix is to always allocate the cookie value, and free it when we are done
using it.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: syzbot+f7e9153b037eac9b1df8@syzkaller.appspotmail.com
CC: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0ee4e76937 ]
ethtool_get_regs() allocates a buffer of size ops->get_regs_len(),
and pass it to the kernel driver via ops->get_regs() for filling.
There is no restriction about what the kernel drivers can or cannot do
with the open ethtool_regs structure. They usually set regs->version
and ignore regs->len or set it to the same size as ops->get_regs_len().
But if userspace allocates a smaller buffer for the registers dump,
we would cause a userspace buffer overflow in the final copy_to_user()
call, which uses the regs.len value potentially reset by the driver.
To fix this, make this case obvious and store regs.len before calling
ops->get_regs(), to only copy as much data as requested by userspace,
up to the value returned by ops->get_regs_len().
While at it, remove the redundant check for non-null regbuf.
Signed-off-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 89dd34caf7 upstream.
The use of ALIGN() in uvc_alloc_entity() is incorrect, since the size of
(entity->pads) is not a power of two. As a stop-gap, until a better
solution is adapted, use roundup() instead.
Found by a static assertion. Compile-tested only.
Fixes: 4ffc2d89f3 ("uvcvideo: Register subdevices for each entity")
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5cec2d2e58 upstream.
An munmap() on a binder device causes binder_vma_close() to be called
which clears the alloc->vma pointer.
If direct reclaim causes binder_alloc_free_page() to be called, there
is a race where alloc->vma is read into a local vma pointer and then
used later after the mm->mmap_sem is acquired. This can result in
calling zap_page_range() with an invalid vma which manifests as a
use-after-free in zap_page_range().
The fix is to check alloc->vma after acquiring the mmap_sem (which we
were acquiring anyway) and skip zap_page_range() if it has changed
to NULL.
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Todd Kjos <tkjos@google.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: stable <stable@vger.kernel.org> # 4.14
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a6e60d8498 upstream.
The upcoming GCC 9 release extends the -Wmissing-attributes warnings
(enabled by -Wall) to C and aliases: it warns when particular function
attributes are missing in the aliases but not in their target.
In particular, it triggers for all the init/cleanup_module
aliases in the kernel (defined by the module_init/exit macros),
ending up being very noisy.
These aliases point to the __init/__exit functions of a module,
which are defined as __cold (among other attributes). However,
the aliases themselves do not have the __cold attribute.
Since the compiler behaves differently when compiling a __cold
function as well as when compiling paths leading to calls
to __cold functions, the warning is trying to point out
the possibly-forgotten attribute in the alias.
In order to keep the warning enabled, we decided to silence
this case. Ideally, we would mark the aliases directly
as __init/__exit. However, there are currently around 132 modules
in the kernel which are missing __init/__exit in their init/cleanup
functions (either because they are missing, or for other reasons,
e.g. the functions being called from somewhere else); and
a section mismatch is a hard error.
A conservative alternative was to mark the aliases as __cold only.
However, since we would like to eventually enforce __init/__exit
to be always marked, we chose to use the new __copy function
attribute (introduced by GCC 9 as well to deal with this).
With it, we copy the attributes used by the target functions
into the aliases. This way, functions that were not marked
as __init/__exit won't have their aliases marked either,
and therefore there won't be a section mismatch.
Note that the warning would go away marking either the extern
declaration, the definition, or both. However, we only mark
the definition of the alias, since we do not want callers
(which only see the declaration) to be compiled as if the function
was __cold (and therefore the paths leading to those calls
would be assumed to be unlikely).
Link: https://lore.kernel.org/lkml/20190123173707.GA16603@gmail.com/
Link: https://lore.kernel.org/lkml/20190206175627.GA20399@gmail.com/
Suggested-by: Martin Sebor <msebor@gcc.gnu.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c0d9782f5b upstream.
From the GCC manual:
copy
copy(function)
The copy attribute applies the set of attributes with which function
has been declared to the declaration of the function to which
the attribute is applied. The attribute is designed for libraries
that define aliases or function resolvers that are expected
to specify the same set of attributes as their targets. The copy
attribute can be used with functions, variables, or types. However,
the kind of symbol to which the attribute is applied (either
function or variable) must match the kind of symbol to which
the argument refers. The copy attribute copies only syntactic and
semantic attributes but not attributes that affect a symbol’s
linkage or visibility such as alias, visibility, or weak.
The deprecated attribute is also not copied.
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html
The upcoming GCC 9 release extends the -Wmissing-attributes warnings
(enabled by -Wall) to C and aliases: it warns when particular function
attributes are missing in the aliases but not in their target, e.g.:
void __cold f(void) {}
void __alias("f") g(void);
diagnoses:
warning: 'g' specifies less restrictive attribute than
its target 'f': 'cold' [-Wmissing-attributes]
Using __copy(f) we can copy the __cold attribute from f to g:
void __cold f(void) {}
void __copy(f) __alias("f") g(void);
This attribute is most useful to deal with situations where an alias
is declared but we don't know the exact attributes the target has.
For instance, in the kernel, the widely used module_init/exit macros
define the init/cleanup_module aliases, but those cannot be marked
always as __init/__exit since some modules do not have their
functions marked as such.
Suggested-by: Martin Sebor <msebor@gcc.gnu.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63cb444418 upstream.
This may confuse user-space clients like plymouth that opens a drm
file descriptor as a result of a hotplug event and then generates a
new event...
Cc: <stable@vger.kernel.org>
Fixes: 5ea1734827 ("drm/vmwgfx: Send a hotplug event at master_set")
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7210e06015 upstream.
The gcc-common.h file did not take into account certain macros that
might have already been defined in the build environment. This updates
the header to avoid redefining the macros, as seen on a Darwin host
using gcc 4.9.2:
HOSTCXX -fPIC scripts/gcc-plugins/arm_ssp_per_task_plugin.o - due to: scripts/gcc-plugins/gcc-common.h
In file included from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3:0:
scripts/gcc-plugins/gcc-common.h:153:0: warning: "__unused" redefined
^
In file included from /usr/include/stdio.h:64:0,
from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/system.h:40,
from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/gcc-plugin.h:28,
from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/plugin.h:23,
from scripts/gcc-plugins/gcc-common.h:9,
from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3:
/usr/include/sys/cdefs.h:161:0: note: this is the location of the previous definition
^
Reported-and-tested-by: "H. Nikolaus Schaller" <hns@goldelico.com>
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 141731d15d upstream.
This reverts most of commit b8eee0e90f ("lockd: Show pid of lockd for
remote locks"), which caused remote locks to not be differentiated between
remote processes for NLM.
We retain the fixup for setting the client's fl_pid to a negative value.
Fixes: b8eee0e90f ("lockd: Show pid of lockd for remote locks")
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: XueWei Zhang <xueweiz@google.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 31fad7d41e upstream.
In cifs_read_allocate_pages, in case of ENOMEM, we go through
whole rdata->pages array but we have failed the allocation before
nr_pages, therefore we may end up calling put_page with NULL
pointer, causing oops
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a67fedd788 upstream.
Commit e895f00a84 ("Staging: wlan-ng: hfa384x_usb.c Fixed too long
code line warnings.") moved the retrieval of the transfer buffer from
the URB from the top of function hfa384x_usbin_callback to a point
after reposting of the URB via a call to submit_rx_urb. The reposting
of the URB allocates a new transfer buffer so the new buffer is
retrieved instead of the buffer containing the response passed into
the callback. This results in failure to initialize the adapter with
an error reported in the system log (something like "CTLX[1] error:
state(Request failed)").
This change moves the retrieval to just before the point where the URB
is reposted so that the correct transfer buffer is retrieved and
initialization of the device succeeds.
Signed-off-by: Tim Collier <osdevtc@gmail.com>
Fixes: e895f00a84 ("Staging: wlan-ng: hfa384x_usb.c Fixed too long code line warnings.")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ca641bae6d upstream.
The create_pagelist() "count" parameter comes from the user in
vchiq_ioctl() and it could overflow. If you look at how create_page()
is called in vchiq_prepare_bulk_data(), then the "size" variable is an
int so it doesn't make sense to allow negatives or larger than INT_MAX.
I don't know this code terribly well, but I believe that typical values
of "count" are typically quite low and I don't think this check will
affect normal valid uses at all.
The "pagelist_size" calculation can also overflow on 32 bit systems, but
not on 64 bit systems. I have added an integer overflow check for that
as well.
The Raspberry PI doesn't offer the same level of memory protection that
x86 does so these sorts of bugs are probably not super critical to fix.
Fixes: 71bad7f086 ("staging: add bcm2708 vchiq driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
