Clean cherry pick of 1d9de44e268d880cbe2d0bd3be1ef0661f93fd34.
If more than one application invokes getrandom(2) before the pool
is ready, then all bar one will be stuck forever because we use
wake_up_interruptible which wakes up a single task.
This patch replaces it with wake_up_all.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Bug: http://b/29621447
Change-Id: I5dfd7abac10898802f030e0a2af7110809283328
(cherry picked from commit 1d9de44e268d880cbe2d0bd3be1ef0661f93fd34)
Almost clean cherry pick of c6e9d6f388,
includes change made by merge 0891ad829d.
The getrandom(2) system call was requested by the LibreSSL Portable
developers. It is analoguous to the getentropy(2) system call in
OpenBSD.
The rationale of this system call is to provide resiliance against
file descriptor exhaustion attacks, where the attacker consumes all
available file descriptors, forcing the use of the fallback code where
/dev/[u]random is not available. Since the fallback code is often not
well-tested, it is better to eliminate this potential failure mode
entirely.
The other feature provided by this new system call is the ability to
request randomness from the /dev/urandom entropy pool, but to block
until at least 128 bits of entropy has been accumulated in the
/dev/urandom entropy pool. Historically, the emphasis in the
/dev/urandom development has been to ensure that urandom pool is
initialized as quickly as possible after system boot, and preferably
before the init scripts start execution.
This is because changing /dev/urandom reads to block represents an
interface change that could potentially break userspace which is not
acceptable. In practice, on most x86 desktop and server systems, in
general the entropy pool can be initialized before it is needed (and
in modern kernels, we will printk a warning message if not). However,
on an embedded system, this may not be the case. And so with this new
interface, we can provide the functionality of blocking until the
urandom pool has been initialized. Any userspace program which uses
this new functionality must take care to assure that if it is used
during the boot process, that it will not cause the init scripts or
other portions of the system startup to hang indefinitely.
SYNOPSIS
#include <linux/random.h>
int getrandom(void *buf, size_t buflen, unsigned int flags);
DESCRIPTION
The system call getrandom() fills the buffer pointed to by buf
with up to buflen random bytes which can be used to seed user
space random number generators (i.e., DRBG's) or for other
cryptographic uses. It should not be used for Monte Carlo
simulations or other programs/algorithms which are doing
probabilistic sampling.
If the GRND_RANDOM flags bit is set, then draw from the
/dev/random pool instead of the /dev/urandom pool. The
/dev/random pool is limited based on the entropy that can be
obtained from environmental noise, so if there is insufficient
entropy, the requested number of bytes may not be returned.
If there is no entropy available at all, getrandom(2) will
either block, or return an error with errno set to EAGAIN if
the GRND_NONBLOCK bit is set in flags.
If the GRND_RANDOM bit is not set, then the /dev/urandom pool
will be used. Unlike using read(2) to fetch data from
/dev/urandom, if the urandom pool has not been sufficiently
initialized, getrandom(2) will block (or return -1 with the
errno set to EAGAIN if the GRND_NONBLOCK bit is set in flags).
The getentropy(2) system call in OpenBSD can be emulated using
the following function:
int getentropy(void *buf, size_t buflen)
{
int ret;
if (buflen > 256)
goto failure;
ret = getrandom(buf, buflen, 0);
if (ret < 0)
return ret;
if (ret == buflen)
return 0;
failure:
errno = EIO;
return -1;
}
RETURN VALUE
On success, the number of bytes that was filled in the buf is
returned. This may not be all the bytes requested by the
caller via buflen if insufficient entropy was present in the
/dev/random pool, or if the system call was interrupted by a
signal.
On error, -1 is returned, and errno is set appropriately.
ERRORS
EINVAL An invalid flag was passed to getrandom(2)
EFAULT buf is outside the accessible address space.
EAGAIN The requested entropy was not available, and
getentropy(2) would have blocked if the
GRND_NONBLOCK flag was not set.
EINTR While blocked waiting for entropy, the call was
interrupted by a signal handler; see the description
of how interrupted read(2) calls on "slow" devices
are handled with and without the SA_RESTART flag
in the signal(7) man page.
NOTES
For small requests (buflen <= 256) getrandom(2) will not
return EINTR when reading from the urandom pool once the
entropy pool has been initialized, and it will return all of
the bytes that have been requested. This is the recommended
way to use getrandom(2), and is designed for compatibility
with OpenBSD's getentropy() system call.
However, if you are using GRND_RANDOM, then getrandom(2) may
block until the entropy accounting determines that sufficient
environmental noise has been gathered such that getrandom(2)
will be operating as a NRBG instead of a DRBG for those people
who are working in the NIST SP 800-90 regime. Since it may
block for a long time, these guarantees do *not* apply. The
user may want to interrupt a hanging process using a signal,
so blocking until all of the requested bytes are returned
would be unfriendly.
For this reason, the user of getrandom(2) MUST always check
the return value, in case it returns some error, or if fewer
bytes than requested was returned. In the case of
!GRND_RANDOM and small request, the latter should never
happen, but the careful userspace code (and all crypto code
should be careful) should check for this anyway!
Finally, unless you are doing long-term key generation (and
perhaps not even then), you probably shouldn't be using
GRND_RANDOM. The cryptographic algorithms used for
/dev/urandom are quite conservative, and so should be
sufficient for all purposes. The disadvantage of GRND_RANDOM
is that it can block, and the increased complexity required to
deal with partially fulfilled getrandom(2) requests.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Zach Brown <zab@zabbo.net>
Bug: http://b/29621447
Change-Id: I189ba74070dd6d918b0fdf83ff30bb74ec0f7556
(cherry picked from commit 4af712e8df)
[flex1911]: backport to 3.4
Clean cherry pick of commit 4af712e8df.
The Tausworthe PRNG is initialized at late_initcall time. At that time the
entropy pool serving get_random_bytes is not filled sufficiently. This
patch adds an additional reseeding step as soon as the nonblocking pool
gets marked as initialized.
On some machines it might be possible that late_initcall gets called after
the pool has been initialized. In this situation we won't reseed again.
(A call to prandom_seed_late blocks later invocations of early reseed
attempts.)
Joint work with Daniel Borkmann.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bug: http://b/29621447
Change-Id: I4d20e60b5df16228f3a3699d16ed2b1dddcceb2b
(cherry picked from commit 4af712e8df)
Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is
disallowed. However, on x86, the first 1MB was always allowed for BIOS
and similar things, regardless of it actually being System RAM. It was
possible for heap to end up getting allocated in low 1MB RAM, and then
read by things like x86info or dd, which would trip hardened usercopy:
usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes)
This changes the x86 exception for the low 1MB by reading back zeros for
System RAM areas instead of blindly allowing them. More work is needed to
extend this to mmap, but currently mmap doesn't go through usercopy, so
hardened usercopy won't Oops the kernel.
Change-Id: I27594af6146e7643217e3babcfd088592b7dbd4b
Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Fix the following NULL pointer dereferences in character drivers.
Null pointer 'pra' that comes from line 825 may be passed to function
and can be dereferenced there by passing argument 4 to function
'fastrpc_internal_invoke' at line 847.
drivers/char/adsprpc.c +847 | fastrpc_device_ioctl()
Null pointer 'rpra' that comes from line 672 may be passed
to function and can be dereferenced there by passing argument 2
to function 'inv_args' at line 702.
drivers/char/adsprpc.c +702 | fastrpc_internal_invoke()
Constant NULL may be dereferenced by passing argument 3 to
function 'diag_device_write' at line 165.
drivers/char/diag/diagfwd_hsic.c +165 | diag_hsic_read_complete_callback()
drivers/char/diag/diagfwd.c +585 | diag_device_write()
Change-Id: I30469575c30f3846b449b6c71522f7dfc10c5bc5
Signed-off-by: Binoy Jayan <bjayan@codeaurora.org>
Add check in order to fix possible integer underflow
during HDLC encoding which may lead to buffer
overflow. Also added check for packet length to
avoid buffer overflow.
Bug: 28767796
Change-Id: Ic91b5ee629066f013022ea139b4a23ec661aa77a
Signed-off-by: Mohit Aggarwal <maggarwa@codeaurora.org>
Signed-off-by: Yuan Lin <yualin@google.com>
At certain point in diag driver there can be integer underflow
thus can lead to memory leak. Added a safeguard for that.
Bug: 28750726
Change-Id: I8cc6a8336cd2c5c88c49748c0be2df1696894f2b
Signed-off-by: Yuan Lin <yualin@google.com>
Check for invalid parameters passed in user invocation
and validate the return values using appropriate macros.
Bug: 28767593
Change-Id: I9a067f2ab151084b46e9d4d5fb945320a27bb7ba
Signed-off-by: Yuan Lin <yualin@google.com>
Diag driver holds on to the socket process task structure even
after signaling the process to exit. This patch clears the internal
handle after signaling.
bug: 28803962
Change-Id: I642fb595fc2caebc6f2f5419efed4fb560e4e4db
Signed-off-by: Ravi Aravamudhan <aravamud@codeaurora.org>
Added checks for DCI request packets to be greater than the minimum
packet length. We would drop the request and print an error otherwise.
CRs-Fixed: 483310
Bug: 28767589
Change-Id: Ib7a713be3d6f5a6e0ec3ac280aebd800058447c7
Signed-off-by: Ravi Aravamudhan <aravamud@codeaurora.org>
Signed-off-by: Yuan Lin <yualin@google.com>
At certain point in diag driver there can be integer overflow
thus can lead to memory leak. Added a safegaurd for it.
Bug: 28769912
Change-Id: Ib7070218b9ea7a1b9efca02b4c456ad9501085cd
Signed-off-by: Katish Paran <kparan@codeaurora.org>
Signed-off-by: Yuan Lin <yualin@google.com>
At certain point in diag driver there can be integer underflow
and thus can lead to memory leak. Bound checks are placed to
ensure correct behavior of condition statements.
Bug: 28768146
Change-Id: I87b57a8b5f32886ada7725f1e8c97cc93de112ec
Signed-off-by: Katish Paran <kparan@codeaurora.org>
Signed-off-by: Yuan Lin <yualin@google.com>
commit 8b572a4200828b4e75cc22ed2f494b58d5372d65 upstream.
In needs_ilk_vtd_wa(), we pass in the GPU device but compared it against
the ids for the mobile GPU and the mobile host bridge. That latter is
impossible and so likely was just a typo for the desktop GPU device id
(which is also buggy).
Fixes commit da88a5f7f7
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed Feb 13 09:31:53 2013 +0000
drm/i915: Disable WC PTE updates to w/a buggy IOMMU on ILK
Reported-by: Ting-Wei Lan <lantw44@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91127
References: https://bugzilla.freedesktop.org/show_bug.cgi?id=60391
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
commit e21404dc0a upstream.
Loading ipmi_si module while bmc is disconnected, we found the timeout
is longer than 5 secs. Actually it takes about 3 mins and 20
secs.(HZ=250)
error message as below:
Dec 12 19:08:59 linux kernel: IPMI BT: timeout in RD_WAIT [ ] 1 retries left
Dec 12 19:08:59 linux kernel: BT: write 4 bytes seq=0x01 03 18 00 01
[...]
Dec 12 19:12:19 linux kernel: IPMI BT: timeout in RD_WAIT [ ]
Dec 12 19:12:19 linux kernel: failed 2 retries, sending error response
Dec 12 19:12:19 linux kernel: IPMI: BT reset (takes 5 secs)
Dec 12 19:12:19 linux kernel: IPMI BT: flag reset [ ]
Function wait_for_msg_done() use schedule_timeout_uninterruptible(1) to
sleep 1 tick, so we should subtract jiffies_to_usecs(1) instead of 100
usecs from timeout.
Reported-by: Hu Shiyuan <hushiyuan@huawei.com>
Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Zefan Li <lizefan@huawei.com>
commit eeb8a7e8bb123e84daeef84f5a2eab99ad2839a2 upstream.
when multiport is off, virtio console invokes config access from irq
context, config access is blocking on s390.
Fix this up by scheduling work from config irq - similar to what we do
for multiport configs.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li <lizefan@huawei.com>
commit 4f6e24ed9de8634d6471ef86b382cba6d4e57ca8 upstream.
when multiport is off, we don't initialize config work,
but we then cancel uninitialized control_work on freeze.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Zefan Li <lizefan@huawei.com>
commit d4c5efdb97 upstream.
zatimend has reported that in his environment (3.16/gcc4.8.3/corei7)
memset() calls which clear out sensitive data in extract_{buf,entropy,
entropy_user}() in random driver are being optimized away by gcc.
Add a helper memzero_explicit() (similarly as explicit_bzero() variants)
that can be used in such cases where a variable with sensitive data is
being cleared out in the end. Other use cases might also be in crypto
code. [ I have put this into lib/string.c though, as it's always built-in
and doesn't need any dependencies then. ]
Fixes kernel bugzilla: 82041
Reported-by: zatimend@hotmail.co.uk
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[lizf: Backported to 3.4:
- adjust context
- another memset() in extract_buf() needs to be converted]
Signed-off-by: Zefan Li <lizefan@huawei.com>
For rotator version 2.0 and above, there is support for fast
YUV which gives better rotator performance. However, there are
few constraints related to height under which fast YUV cannot be
enabled when 90 degree rotation is enabled. Make sure
to add proper checks before enabling fast YUV.
Change-Id: Iafd204a6e4ef09e1151d01d8fde35359b7c3b7a5
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Bug: 19043183
Even though cancel_delayed_work should cancel the worker thread
in some race condition it can fail and get scheduled.
To avoid this situation use cancel_delayed_work_sync.
Also rotator_lock mutex need not be unlocked while waiting for isr
as isr does not aquire this mutex for doing its operations.
It is after this unlock of mutex sometimes in race condition rotator
clock is getting disabled via the msm_rotator_rot_clk_work_f
Conflicts:
drivers/char/msm_rotator.c
Change-Id: I5405f2c4d9505c1b288d1f1ac3d9892955306f87
Signed-off-by: Justin Philip <jphili@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Due to asynchronuous rotator mechanism, sometimes the
MSM_ROTATOR_IOCTL_FINISH arrives before the previously queued
do_rotate work is completed. This causes fence to be signalled
before the buffer is used by rotator. In case of fast YUV 2 pass
scenario, this causes IOMMU page fault on 2 pass buffers, since
the buffer is unmapped when the rotator is still using it. Hence,
wait for the pending commit works to be finished before releasing
the fence and freeing the 2 pass buffers.
Change-Id: Iec9edd11406d102c7dd102c2ad7935184bbbba93
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
commit 8bab797c6e upstream.
This is a static checker fix. The "dev" variable is always NULL after
the while statement so we would be dereferencing a NULL pointer here.
Fixes: 819a3eba42 ('[PATCH] applicom: fix error handling')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9ba5c80b1a upstream.
When multiple ovq operations are being performed (lots of open/close
operations on virtio_console fds), the __send_control_msg() function can
get confused without locking.
A simple recipe to cause badness is:
* create a QEMU VM with two virtio-serial ports
* in the guest, do
while true;do echo abc >/dev/vport0p1;done
while true;do echo edf >/dev/vport0p2;done
In one run, this caused a panic in __send_control_msg(). In another, I
got
virtio_console virtio0: control-o:id 0 is not a head!
This also results repeated messages similar to these on the host:
qemu-kvm: virtio-serial-bus: Unexpected port id 478762112 for device virtio-serial-bus.0
qemu-kvm: virtio-serial-bus: Unexpected port id 478762368 for device virtio-serial-bus.0
Reported-by: FuXiangChun <xfu@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[wyj: Backported to 3.4: adjust context]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 165b1b8bbc upstream.
The cvq_lock was taken for the c_ivq. Rename the lock to make that
obvious.
We'll also add a lock around the c_ovq in the next commit, so there's no
ambiguity.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Asias He <asias@redhat.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
[bwh: Backported to 3.2:
- Adjust context
- Drop change to virtcons_restore()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[wyj: Backported to 3.4:
- pick change to virtcons_restore() from upsteam patch]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 10b3a32d29 upstream.
Commit 902c098a36 ("random: use lockless techniques in the interrupt
path") turned IRQ path from being spinlock protected into lockless
cmpxchg-retry update.
That commit removed r->lock serialization between crediting entropy bits
from IRQ context and accounting when extracting entropy on userspace
read path, but didn't turn the r->entropy_count reads/updates in
account() to use cmpxchg as well.
It has been observed, that under certain circumstances this leads to
read() on /dev/urandom to return 0 (EOF), as r->entropy_count gets
corrupted and becomes negative, which in turn results in propagating 0
all the way from account() to the actual read() call.
Convert the accounting code to be the proper lockless counterpart of
what has been partially done by 902c098a36.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Greg KH <greg@kroah.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>
Cc: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit eb6d78ec21 upstream.
The OBF timer in KCS was not reset in one situation when error recovery
was started, resulting in an immediate timeout.
Reported-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 48e8ac2979 upstream.
With recent changes it is possible for the timer handler to detect an
idle interface and not start the timer, but the thread to start an
operation at the same time. The thread will not start the timer in that
instance, resulting in the timer not running.
Instead, move all timer operations under the lock and start the timer in
the thread if it detect non-idle and the timer is not already running.
Moving under locks allows the last timeout to be set in both the thread
and the timer. 'Timer is not running' means that the timer is not
pending and smi_timeout() is not running. So we need a flag to detect
this correctly.
Also fix a few other timeout bugs: setting the last timeout when the
interrupt has to be disabled and the timer started, and setting the last
timeout in check_start_timer_thread possibly racing with the timer
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a94cdd1f4d upstream.
In read_all_bytes, we do
unsigned char i;
...
bt->read_data[0] = BMC2HOST;
bt->read_count = bt->read_data[0];
...
for (i = 1; i <= bt->read_count; i++)
bt->read_data[i] = BMC2HOST;
If bt->read_data[0] == bt->read_count == 255, we loop infinitely in the
'for' loop. Make 'i' an 'int' instead of 'char' to get rid of the
overflow and finish the loop after 255 iterations every time.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-and-debugged-by: Rui Hui Dian <rhdian@novell.com>
Cc: Tomas Cech <tcech@suse.cz>
Cc: Corey Minyard <minyard@acm.org>
Cc: <openipmi-developer@lists.sourceforge.net>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5bbb2ae3d6 upstream.
bind_get() checks the device number it is called with. It uses
MAX_RAW_MINORS for the upper bound. But MAX_RAW_MINORS is set at compile
time while the actual number of raw devices can be set at runtime. This
means the test can either be too strict or too lenient. And if the test
ends up being too lenient bind_get() might try to access memory beyond
what was allocated for "raw_devices".
So check against the runtime value (max_raw_minors) in this function.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 47d06e532e upstream.
The some platforms (e.g., ARM) initializes their clocks as
late_initcalls for some unknown reason. So make sure
random_int_secret_init() is run after all of the late_initcalls are
run.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When rotator prepare fails, timeline is not signalled causing fence
timeout on the rotator release fence. This patch fixes the issue.
Change-Id: I6023393d768dbb1a0a9095bb1822ac504632ed64
Signed-off-by: Vishnuvardhan Prodduturi <vproddut@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
commit c5857ccf29 upstream.
With the new interrupt sampling system, we are no longer using the
timer_rand_state structure in the irq descriptor, so we can stop
initializing it now.
[ Merged in fixes from Sedat to find some last missing references to
rand_initialize_irq() ]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit c2557a303a upstream.
Create a new function, get_random_bytes_arch() which will use the
architecture-specific hardware random number generator if it is
present. Change get_random_bytes() to not use the HW RNG, even if it
is avaiable.
The reason for this is that the hw random number generator is fast (if
it is present), but it requires that we trust the hardware
manufacturer to have not put in a back door. (For example, an
increasing counter encrypted by an AES key known to the NSA.)
It's unlikely that Intel (for example) was paid off by the US
Government to do this, but it's impossible for them to prove otherwise
--- especially since Bull Mountain is documented to use AES as a
whitener. Hence, the output of an evil, trojan-horse version of
RDRAND is statistically indistinguishable from an RDRAND implemented
to the specifications claimed by Intel. Short of using a tunnelling
electronic microscope to reverse engineer an Ivy Bridge chip and
disassembling and analyzing the CPU microcode, there's no way for us
to tell for sure.
Since users of get_random_bytes() in the Linux kernel need to be able
to support hardware systems where the HW RNG is not present, most
time-sensitive users of this interface have already created their own
cryptographic RNG interface which uses get_random_bytes() as a seed.
So it's much better to use the HW RNG to improve the existing random
number generator, by mixing in any entropy returned by the HW RNG into
/dev/random's entropy pool, but to always _use_ /dev/random's entropy
pool.
This way we get almost of the benefits of the HW RNG without any
potential liabilities. The only benefits we forgo is the
speed/performance enhancements --- and generic kernel code can't
depend on depend on get_random_bytes() having the speed of a HW RNG
anyway.
For those places that really want access to the arch-specific HW RNG,
if it is available, we provide get_random_bytes_arch().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit e6d4947b12 upstream.
If the CPU supports a hardware random number generator, use it in
xfer_secondary_pool(), where it will significantly improve things and
where we can afford it.
Also, remove the use of the arch-specific rng in
add_timer_randomness(), since the call is significantly slower than
get_cycles(), and we're much better off using it in
xfer_secondary_pool() anyway.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit a2080a67ab upstream.
Add a new interface, add_device_randomness() for adding data to the
random pool that is likely to differ between two devices (or possibly
even per boot). This would be things like MAC addresses or serial
numbers, or the read-out of the RTC. This does *not* add any actual
entropy to the pool, but it initializes the pool to different values
for devices that might otherwise be identical and have very little
entropy available to them (particularly common in the embedded world).
[ Modified by tytso to mix in a timestamp, since there may be some
variability caused by the time needed to detect/configure the hardware
in question. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit 902c098a36 upstream.
The real-time Linux folks don't like add_interrupt_randomness() taking
a spinlock since it is called in the low-level interrupt routine.
This also allows us to reduce the overhead in the fast path, for the
random driver, which is the interrupt collection path.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit 775f4b297b upstream.
We've been moving away from add_interrupt_randomness() for various
reasons: it's too expensive to do on every interrupt, and flooding the
CPU with interrupts could theoretically cause bogus floods of entropy
from a somewhat externally controllable source.
This solves both problems by limiting the actual randomness addition
to just once a second or after 64 interrupts, whicever comes first.
During that time, the interrupt cycle data is buffered up in a per-cpu
pool. Also, we make sure the the nonblocking pool used by urandom is
initialized before we start feeding the normal input pool. This
assures that /dev/urandom is returning unpredictable data as soon as
possible.
(Based on an original patch by Linus, but significantly modified by
tytso.)
Tested-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Eric Wustrow <ewust@umich.edu>
Reported-by: Nadia Heninger <nadiah@cs.ucsd.edu>
Reported-by: Zakir Durumeric <zakir@umich.edu>
Reported-by: J. Alex Halderman <jhalderm@umich.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ed Tam <etam@google.com>
commit 96f97a8391 upstream.
If a port gets unplugged while a user is blocked on read(), -ENODEV is
returned. However, subsequent read()s returned 0, indicating there's no
host-side connection (but not indicating the device went away).
This also happened when a port was unplugged and the user didn't have
any blocking operation pending. If the user didn't monitor the SIGIO
signal, they won't have a chance to find out if the port went away.
Fix by returning -ENODEV on all read()s after the port gets unplugged.
write() already behaves this way.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 92d3453815 upstream.
SIGIO should be sent when a port gets unplugged. It should only be sent
to prcesses that have the port opened, and have asked for SIGIO to be
delivered. We were clearing out guest_connected before calling
send_sigio_to_port(), resulting in a sigio not getting sent to
processes.
Fix by setting guest_connected to false after invoking the sigio
function.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ea3768b438 upstream.
We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped. This is
actually unnecessary, and resulted in buggy behaviour:
1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one
This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).
This behaviour resulted in a warning message like this one:
-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'
Call Trace:
[<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
[<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
[<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
[<ffffffff811f23e8>] ? create_dir+0x68/0xb0
[<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
[<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
[<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
[<ffffffff812734b4>] ? kobject_add+0x44/0x70
[<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
[<ffffffff8134b389>] ? device_add+0xc9/0x650
-------------------8<---------------------------------------
Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers. Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.
This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:
-------------------8<---------------------------------------
PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat"
#0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
#1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
#2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
#3 [ffff88011b9d5bf0] die at ffffffff8100f26b
#4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
#5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
[exception RIP: strlen+2]
RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000
RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030
RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500
R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10
R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
#7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
#8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
#9 [ffff88011b9d5de0] device_del at ffffffff813440c7
-------------------8<---------------------------------------
So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.
Reported-by: chayang <chayang@redhat.com>
Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com>
Reported-by: FuXiangChun <xfu@redhat.com>
Reported-by: Qunfang Zhang <qzhang@redhat.com>
Reported-by: Sibiao Luo <sluo@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 671bdea2b9 upstream.
Between open() being called and processed, the port can be unplugged.
Check if this happened, and bail out.
A simple test script to reproduce this is:
while true; do for i in $(seq 1 100); do echo $i > /dev/vport0p3; done; done;
This opens and closes the port a lot of times; unplugging the port while
this is happening triggers the bug.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 057b82be3c upstream.
There's a window between find_port_by_devt() returning a port and us
taking a kref on the port, where the port could get unplugged. Fix it
by taking the reference in find_port_by_devt() itself.
Problem reported and analyzed by Mateusz Guzik.
Reported-by: Mateusz Guzik <mguzik@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There has two bugs.
1. For example, the 'psaux' device will use '1' as minor number to
register misc device, but misc deriver doesn't set the '1' as used.
It's the root casue for duplicate filename.
2. From warning message, minor number '1' is the one of duplicate
fileanme, it meanes the number of dynamic minor is not enough.
The symptom of creating duplicate filename:
------------[ cut here ]------------
WARNING: at fs/sysfs/dir.c:508 sysfs_add_one+0x7c/0x9c()
sysfs: cannot create duplicate filename '/dev/char/10:1'
[<c00148b8>] (unwind_backtrace+0x0/0x11c) from
[<c007f828>] (warn_slowpath_common+0x48/0x60)
[<c007f898>] (warn_slowpath_fmt+0x2c/0x3c)
[<c018696c>] (sysfs_add_one+0x7c/0x9c)
[<c01874b4>] (sysfs_do_create_link+0x10c/0x1f8)
[<c03bd6c0>] (device_add+0x1ac/0x5e4)
[<c03be24c>] (device_create_vargs+0x8c/0xd0)
[<c03be2ac>] (device_create+0x1c/0x24)
[<c037c7a4>] (misc_register+0xb4/0x118)
[<c0e30c1c>] (init_log+0x10/0x4c)
[<c0e009d8>] (do_one_initcall+0x90/0x160)
[<c0e00b94>] (kernel_init+0xec/0x1a8)
[<c000f468>] (kernel_thread_exit+0x0/0x8)
---[ end trace da227214a82491b9 ]---
BUG 8889112
Change-Id: I186a945a56fc831f59e19509365a0ae8a481bb2d
Signed-off-by: singhome_lee <singhome_lee@asus.com>
commit 6368087e85 upstream.
When a 32 bit version of ipmitool is used on a 64 bit kernel, the
ipmi_devintf code fails to correctly acquire ipmi_mutex. This results in
incomplete data being retrieved in some cases, or other possible failures.
Add a wrapper around compat_ipmi_ioctl() to take ipmi_mutex to fix this.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2323036dfe upstream.
This is my example conversion of a few existing mmap users. The HPET
case is simple, widely available, and easy to test (Clemens Ladisch sent
a trivial test-program for it).
Test-program-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Send request to a work queue and return right away.
Work queue will go through the commit queue to do the
rotation. wait_for_finish can be set to true to make
rotation go back to blocking.
Change-Id: Ifc2e36bd24d9681d42105f4ccbb62a8777af2a6c
Signed-off-by: Ken Zhang <kenz@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
Add MSM_ROTATOR_IOCTL_BUFFER_SYNC ioctl interface.
Rotator will create a timeline for each session at START, wait for
input fence and create released fence in this ioctl call,
signal the timeline after rotation is done.
Change-Id: I3738f8287d804ccd94e0a16ac0afb8b41b299c75
Signed-off-by: Ken Zhang <kenz@codeaurora.org>
Signed-off-by: Naseer Ahmed <naseer@codeaurora.org>
