eCryptfs: Force RO mount when encrypted view is enabled

The ecryptfs_encrypted_view mount option greatly changes the
functionality of an eCryptfs mount. Instead of encrypting and decrypting
lower files, it provides a unified view of the encrypted files in the
lower filesystem. The presence of the ecryptfs_encrypted_view mount
option is intended to force a read-only mount and modifying files is not
supported when the feature is in use. See the following commit for more
information:

  e77a56d [PATCH] eCryptfs: Encrypted passthrough

This patch forces the mount to be read-only when the
ecryptfs_encrypted_view mount option is specified by setting the
MS_RDONLY flag on the superblock. Additionally, this patch removes some
broken logic in ecryptfs_open() that attempted to prevent modifications
of files when the encrypted view feature was in use. The check in
ecryptfs_open() was not sufficient to prevent file modifications using
system calls that do not operate on a file descriptor.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Priya Bansal <p.bansal@samsung.com>
Cc: stable@vger.kernel.org # v2.6.21+: e77a56d [PATCH] eCryptfs: Encrypted passthrough
eCryptfs: Remove unnecessary casts when parsing packet lengths

The elements in the data array are already unsigned chars and do not
need to be casted.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
module: Wait for RCU synchronizing before releasing a module

Wait for RCU synchronizing on failure path of module loading
before releasing struct module, because the memory of mod->list
can still be accessed by list walkers (e.g. kallsyms).

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
module: Unlink module with RCU synchronizing instead of stop_machine

Unlink module from module list with RCU synchronizing instead
of using stop_machine(). Since module list is already protected
by rcu, we don't need stop_machine() anymore.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
lib/bug: Use RCU list ops for module_bug_list

Actually since module_bug_list should be used in BUG context,
we may not need this. But for someone who want to use this
from normal context, this makes module_bug_list an RCU list.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
module: Replace module_ref with atomic_t refcnt

Replace module_ref per-cpu complex reference counter with
an atomic_t simple refcnt. This is for code simplification.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
module: Remove stop_machine from module unloading

Remove stop_machine from module unloading by adding new reference
counting algorithm.

This atomic refcounter works like a semaphore, it can get (be
incremented) only when the counter is not 0. When loading a module,
kmodule subsystem sets the counter MODULE_REF_BASE (= 1). And when
unloading the module, it subtracts MODULE_REF_BASE from the counter.
If no one refers the module, the refcounter becomes 0 and we can
remove the module safely. If someone referes it, we try to recover
the counter by adding MODULE_REF_BASE unless the counter becomes 0,
because the referrer can put the module right before recovering.
If the recovering is failed, we can get the 0 refcount and it
never be incremented again, it can be removed safely too.

Note that __module_get() forcibly gets the module refcounter,
users should use try_module_get() instead of that.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
kernel:module Fix coding style errors and warnings.

Fixed codin style errors and warnings. Changes printk with
print_debug/warn. Changed seq_printf to seq_puts.

Signed-off-by: Ionut Alexa <ionut.m.alexa@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed bogus KERN_DEFAULT conversion)
params: cleanup sysfs allocation

commit 63662139e519ce06090b2759cf4a1d291b9cc0e2 attempted to patch a
leak (which would only happen on OOM, ie. never), but it didn't quite
work.

This rewrites the code to be as simple as possible.  add_sysfs_param()
adds a parameter.  If it fails, it's the caller's responsibility to
clean up the parameters which already exist.

The kzalloc-then-always-krealloc pattern is perhaps overly simplistic,
but this code has clearly confused people.  It worked on me...

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
drivers: platform: change 0x20 to I8042_STR_AUXDATA in i8042 filters

Instead of using a magic constant 0x20 in some drivers to get data only
from the KBC port we should use the constant defined in i8042.h with
the same value. Also, this makes these drivers uniform with what
constant the only other filter function uses in
drivers/input/misc/ideapad_slidebar.c.

Signed-off-by: Giedrius Statkevičius <giedriuswork@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: flatten control flow

In eeepc_rfkill_hotplug there's an if statement with a big tail that
ends right before the out_unlock label. We might as well invert the
condition and jump to out_unlock in that case, pretty much like the rest
of the code does. This removes an indentation level for a large chunk of
code and also stops suggesting there might be an else clause.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: don't break user visible strings

As per Documentation/CodingStyle ch. 2, it is preferred that we don't
break user visible strings, in order to allow users to grep for them.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: define rfkill notifier nodes only once

The rfkill notifier node names are used in three different places. As a
matter of style, it is better to store them somewhere and have the
compiler warn us about typos in the function arguments.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: replace magic numbers with defines

eeepc_[gs]et_fan_ctrl uses some magic numbers. These numbers mean
something more than just the number. Describe them with macros instead
of comments in one of the functions.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: document fan_pwm conversions

eeepc_get_fan_pwm and eeepc_set_fan_pwm convert the PWM value read from
the fan to a range lmsensors understands. Unfortunately this is only
clear if you are familiar with how lmsensors handles duty cycles.

Introduce two conversion functions that document the goal of these
conversions.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: don't assume get_acpi succeeds

In eeepc_hotk_thaw, we assume that get_acpi() will effectively return a
bool. However, it is possible that get_acpi() returns an error instead.
We should not be writing error values to the ACPI device, even though
it's quite possible that we couldn't contact the ACPI device in the
first place.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
intel_ips: fix a comment typo

s/tempurature/temperature/

Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eeepc-laptop: clean up control flow in eeepc_acpi_notify

eeepc_acpi_notify increases the indentation level to a whopping four. If
we revise the conditions a bit, we can reduce that to a more soothing
two and satisfy the indentation guidelines in Documentation/CodingStyle.

Remove an unwanted space while we're in the neighbourhood.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
dell-wmi: Update code for processing WMI events

The WMI buffer can contain multiple events. First value in buffer is
length of event followed by data of specified length. After that is next
length and next data.  When length is zero then there is no more events
in bufffer.

This patch adds support for processing all events in buffer (not only
first) and parse more event types (not only hotkey events). Because of
variable length of events sometimes BIOS fills more hotkeys (or other
values) into single WMI event. In this case this patch also processes
these multiple hotkeys (and not only first one).

Some event types are just ignored because kernel is not interested in
them (e.g. NIC Link status, battery unplug, ...).

This patch is based on DSDT table from Dell Latitude E6440. Code should
be backward compatible so will process other events of old types same as
before this patch.

This patch also fixes a problem with unknown WMI event messages being
written to the log. Now all known events are parsed and those which are
not interesting to the kernel are dropped without an unknown WMI event
message.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
eCryptfs: Remove buggy and unnecessary write in file name decode routine

Dmitry Chernenkov used KASAN to discover that eCryptfs writes past the
end of the allocated buffer during encrypted filename decoding. This
fix corrects the issue by getting rid of the unnecessary 0 write when
the current bit offset is 2.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Reported-by: Dmitry Chernenkov <dmitryc@google.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org # v2.6.29+: 51ca58d eCryptfs: Filename Encryption: Encoding and encryption functions
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>