USB: usb_wwan: fix race between write and resume

commit d9e93c08d8d985e5ef89436ebc9f4aad7e31559f upstream.

We find a race between write and resume. usb_wwan_resume run play_delayed()
and spin_unlock, but intfdata->suspended still is not set to zero.
At this time usb_wwan_write is called and anchor the urb to delay
list. Then resume keep running but the delayed urb have no chance
to be commit until next resume. If the time of next resume is far
away, tty will be blocked in tty_wait_until_sent during time. The
race also can lead to writes being reordered.

This patch put play_Delayed and intfdata->suspended together in the
spinlock, it's to avoid the write race during resume.

Fixes: 383cedc3bb43 ("USB: serial: full autosuspend support for the
option driver")

Signed-off-by: xiao jin <jin.xiao@intel.com>
Signed-off-by: Zhang, Qi1 <qi1.zhang@intel.com>
Reviewed-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/usb/serial/usb_wwan.c
USB: usb_wwan: fix write and suspend race

commit 170fad9e22df0063eba0701adb966786d7a4ec5a upstream.

Fix race between write() and suspend() which could lead to writes being
dropped (or I/O while suspended) if the device is runtime suspended
while a write request is being processed.

Specifically, suspend() releases the susp_lock after determining the
device is idle but before setting the suspended flag, thus leaving a
window where a concurrent write() can submit an urb.

Fixes: 383cedc3bb43 ("USB: serial: full autosuspend support for the
option driver")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/usb/serial/usb_wwan.c
USB: sierra: fix AA deadlock in open error path

commit 353fe198602e8b4d1c7bdcceb8e60955087201b1 upstream.

Fix AA deadlock in open error path that would call close() and try to
grab the already held disc_mutex.

Fixes: b9a44bc19f48 ("sierra: driver urb handling improvements")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: sierra: fix use after free at suspend/resume

commit 8452727de70f6ad850cd6d0aaa18b5d9050aa63b upstream.

Fix use after free or NULL-pointer dereference during suspend and
resume.

The port data may never have been allocated (port probe failed)
or may already have been released by port_remove (e.g. driver is
unloaded) when suspend and resume are called.

Fixes: e6929a9020ac ("USB: support for autosuspend in sierra while
online")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: sierra: fix urb and memory leak in resume error path

commit 7fdd26a01eb7b6cb6855ff8f69ef4a720720dfcb upstream.

Neither the transfer buffer or the urb itself were released in the
resume error path for delayed writes. Also on errors, the remainder of
the queue was not even processed, which leads to further urb and buffer
leaks.

The same error path also failed to balance the outstanding-urb counter,
something which results in degraded throughput or completely blocked
writes.

Fix this by releasing urb and buffer and balancing counters on errors,
and by always processing the whole queue even when submission of one urb
fails.

Fixes: e6929a9020ac ("USB: support for autosuspend in sierra while
online")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: sierra: fix urb and memory leak on disconnect

commit 014333f77c0b71123d6ef7d31a9724e0699c9548 upstream.

The delayed-write queue was never emptied on disconnect, something which
would lead to leaked urbs and transfer buffers if the device is
disconnected before being runtime resumed due to a write.

Fixes: e6929a9020ac ("USB: support for autosuspend in sierra while
online")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: sierra: fix remote wakeup

commit 80cc0fcbdaeaf10d04ba27779a2d7ceb73d2717a upstream.

Make sure that needs_remote_wake up is always set when there are open
ports.

Currently close() would unconditionally set needs_remote_wakeup to 0
even though there might still be open ports. This could lead to blocked
input and possibly dropped data on devices that do not support remote
wakeup (and which must therefore not be runtime suspended while open).

Add an open_ports counter (protected by the susp_lock) and only clear
needs_remote_wakeup when the last port is closed.

Fixes: e6929a9020ac ("USB: support for autosuspend in sierra while
online")

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ACPI: Fix conflict between customized DSDT and DSDT local copy

commit 73577d1df8e1f31f6b1a5eebcdbc334eb0330e47 upstream.

This patch fixes the following issue:
If DSDT is customized, no local DSDT copy is needed.

References: https://bugzilla.kernel.org/show_bug.cgi?id=69711
Signed-off-by: Enrico Etxe Arte <goitizena.generoa@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[rjw: Subject]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM: stacktrace: avoid listing stacktrace functions in stacktrace

commit 3683f44c42e991d313dc301504ee0fca1aeb8580 upstream.

While debugging the FEC ethernet driver using stacktrace, it was noticed
that the stacktraces always begin as follows:

 [<c00117b4>] save_stack_trace_tsk+0x0/0x98
 [<c0011870>] save_stack_trace+0x24/0x28
 ...

This is because the stack trace code includes the stack frames for itself.
This is incorrect behaviour, and also leads to "skip" doing the wrong
thing (which is the number of stack frames to avoid recording.)

Perversely, it does the right thing when passed a non-current thread.  Fix
this by ensuring that we have a known constant number of frames above the
main stack trace function, and always skip these.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	arch/arm/kernel/stacktrace.c
target: Explicitly clear ramdisk_mcp backend pages

[Note that a different patch to address the same issue went in during
v3.15-rc1 (commit 4442dc8a), but includes a bunch of other changes that
don't strictly apply to fixing the bug]

This patch changes rd_allocate_sgl_table() to explicitly clear
ramdisk_mcp backend memory pages by passing __GFP_ZERO into
alloc_pages().

This addresses a potential security issue where reading from a
ramdisk_mcp could return sensitive information, and follows what
>= v3.15 does to explicitly clear ramdisk_mcp memory at backend
device initialization time.

Reported-by: Jorge Daniel Sequeira Matias <jdsm@tecnico.ulisboa.pt>
Cc: Jorge Daniel Sequeira Matias <jdsm@tecnico.ulisboa.pt>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86-32, espfix: Remove filter for espfix32 due to race

commit 246f2d2ee1d715e1077fc47d61c394569c8ee692 upstream.

It is not safe to use LAR to filter when to go down the espfix path,
because the LDT is per-process (rather than per-thread) and another
thread might change the descriptors behind our back.  Fortunately it
is always *safe* (if a bit slow) to go down the espfix path, and a
32-bit LDT stack segment is extremely rare.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, x32: Use compat shims for io_{setup,submit}

commit 7fd44dacdd803c0bbf38bf478d51d280902bb0f1 upstream.

The io_setup takes a pointer to a context id of type aio_context_t.
This in turn is typed to a __kernel_ulong_t.  We could tweak the
exported headers to define this as a 64bit quantity for specific
ABIs, but since we already have a 32bit compat shim for the x86 ABI,
let's just re-use that logic.  The libaio package is also written to
expect this as a pointer type, so a compat shim would simplify that.

The io_submit func operates on an array of pointers to iocb structs.
Padding out the array to be 64bit aligned is a huge pain, so convert
it over to the existing compat shim too.

We don't convert io_getevents to the compat func as its only purpose
is to handle the timespec struct, and the x32 ABI uses 64bit times.

With this change, the libaio package can now pass its testsuite when
built for the x32 ABI.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Link: http://lkml.kernel.org/r/1399250595-5005-1-git-send-email-vapier@gentoo.org
Cc: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
genirq: Sanitize spurious interrupt detection of threaded irqs

commit 1e77d0a1ed7417d2a5a52a7b8d32aea1833faa6c upstream.

Till reported that the spurious interrupt detection of threaded
interrupts is broken in two ways:

- note_interrupt() is called for each action thread of a shared
  interrupt line. That's wrong as we are only interested whether none
  of the device drivers felt responsible for the interrupt, but by
  calling multiple times for a single interrupt line we account
  IRQ_NONE even if one of the drivers felt responsible.

- note_interrupt() when called from the thread handler is not
  serialized. That leaves the members of irq_desc which are used for
  the spurious detection unprotected.

To solve this we need to defer the spurious detection of a threaded
interrupt to the next hardware interrupt context where we have
implicit serialization.

If note_interrupt is called with action_ret == IRQ_WAKE_THREAD, we
check whether the previous interrupt requested a deferred check. If
not, we request a deferred check for the next hardware interrupt and
return.

If set, we check whether one of the interrupt threads signaled
success. Depending on this information we feed the result into the
spurious detector.

If one primary handler of a shared interrupt returns IRQ_HANDLED we
disable the deferred check of irq threads on the same line, as we have
found at least one device driver who cared.

Reported-by: Till Straumann <strauman@slac.stanford.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Austin Schuh <austin@peloton-tech.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-can@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1303071450130.22263@ionos
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
skbuff: add an api to orphan frags

commit a353e0ce0fd42d8859260666d1e9b10f2abd4698 upstream.

Many places do
       if ((skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY))
		skb_copy_ubufs(skb, gfp_mask);
to copy and invoke frag destructors if necessary.
Add an inline helper for this.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
skbuff: export skb_copy_ubufs

commit dcc0fb782b3a6e2abfeaaeb45dd88ed09596be0f upstream.

Export skb_copy_ubufs so that modules can orphan frags.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
skbuff: skb_segment: orphan frags before copying

commit 1fd819ecb90cc9b822cd84d3056ddba315d3340f upstream.

skb_segment copies frags around, so we need
to copy them carefully to avoid accessing
user memory after reporting completion to userspace
through a callback.

skb_segment doesn't normally happen on datapath:
TSO needs to be disabled - so disabling zero copy
in this case does not look like a big deal.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2.  As skb_segment() only supports page-frags *or* a
 frag list, there is no need for the additional frag_skb pointer or the
 preparatory renaming.]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Btrfs: fix double free in find_lock_delalloc_range

commit 7d78874273463a784759916fc3e0b4e2eb141c70 upstream.

We need to NULL the cached_state after freeing it, otherwise
we might free it again if find_delalloc_range doesn't find anything.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs: btrfs: volumes.c: Fix for possible null pointer dereference

commit 8321cf2596d283821acc466377c2b85bcd3422b7 upstream.

There is otherwise a risk of a possible null pointer dereference.

Was largely found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Btrfs: use right type to get real comparison

commit cd857dd6bc2ae9ecea14e75a34e8a8fdc158e307 upstream.

We want to make sure the point is still within the extent item, not to verify
the memory it's pointing to.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
btrfs: fix use of uninit "ret" in end_extent_writepage()

commit 3e2426bd0eb980648449e7a2f5a23e3cd3c7725c upstream.

If this condition in end_extent_writepage() is false:

	if (tree->ops && tree->ops->writepage_end_io_hook)

we will then test an uninitialized "ret" at:

	ret = ret < 0 ? ret : -EIO;

The test for ret is for the case where ->writepage_end_io_hook
failed, and we'd choose that ret as the error; but if
there is no ->writepage_end_io_hook, nothing sets ret.

Initializing ret to 0 should be sufficient; if
writepage_end_io_hook wasn't set, (!uptodate) means
non-zero err was passed in, so we choose -EIO in that case.

Signed-of-by: Eric Sandeen <sandeen@redhat.com>

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>