commit 72bb99cfe9 upstream.
In the situation that a writer fails to copy data from userspace it will reset
the write offset to the value it had before it went to sleep. This discarding
any messages written while aquiring the mutex.
Therefore the reset offset needs to be retrieved after acquiring the mutex.
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we pass an invalid clock type then "ts" is never set. We need to
check for errors earlier, otherwise we end up passing uninitialized
stack data to userspace.
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Smatch complains that if we pass an invalid clock type then "ts" is
never set. We need to check for errors earlier, otherwise we end up
passing uninitialized stack data to userspace.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull removal of GENERIC_GPIO from Grant Likely:
"GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any
valid cases for enableing GENERIC_GPIO without GPIOLIB, even though it
is possible to do so which has been causing confusion and breakage.
This branch does the work to completely eliminate GENERIC_GPIO."
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux:
gpio: update gpio Chinese documentation
Remove GENERIC_GPIO config option
Convert selectors of GENERIC_GPIO to GPIOLIB
blackfin: force use of gpiolib
m68k: coldfire: use gpiolib
mips: pnx833x: remove requirement for GENERIC_GPIO
openrisc: default GENERIC_GPIO to false
avr32: default GENERIC_GPIO to false
xtensa: remove explicit selection of GENERIC_GPIO
sh: replace CONFIG_GENERIC_GPIO by CONFIG_GPIOLIB
powerpc: remove redundant GENERIC_GPIO selection
unicore32: default GENERIC_GPIO to false
unicore32: remove unneeded select GENERIC_GPIO
arm: plat-orion: use GPIO driver on CONFIG_GPIOLIB
arm: remove redundant GENERIC_GPIO selection
mips: alchemy: require gpiolib
mips: txx9: change GENERIC_GPIO to GPIOLIB
mips: loongson: use GPIO driver on CONFIG_GPIOLIB
mips: remove redundant GENERIC_GPIO select
GENERIC_GPIO is now equivalent to GPIOLIB and features that depended on
GENERIC_GPIO can now depend on GPIOLIB to allow removal of this option.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
This patch modifies the IOCTL macros to use user-exportable data types,
as they are the referred kernel types for the user/kernel interface.
The patch does not change in any way the functionality of the binder driver.
Signed-off-by: Serban Constantinescu <serban.constantinescu@arm.com>
Acked-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Debug messages sent in binder_deferred_release begin with
"binder_release:" which is a bit misleading as binder_release is not
directly part of the call stack. Use __func__ instead for debug messages
in binder_deferred_release.
Signed-off-by: Mirsal Ennaime <mirsal@mirsal.fr>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove one level of indentation from the binder proc page release code
by using slightly different control semantics.
Signed-off-by: Mirsal Ennaime <mirsal@mirsal.fr>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Use tabs where applicable
* Remove a few "80-columns" checkpatch warnings
* Separate code paths with empty lines for readability
Signed-off-by: Mirsal Ennaime <mirsal@mirsal.fr>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The binder_deferred_release() function has many levels of indentation
which makes it difficult to read. This patch moves the code which deals
with disposing of a binder node to a separate binder_node_release()
function, thus removing one level of indentation and allowing the code to
fit in 80 columns.
Signed-off-by: Mirsal Ennaime <mirsal@mirsal.fr>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Kconfig entry for the "Anonymous Shared Memory Subsystem" got added
in v3.3. It has an optional dependency on TINY_SHMEM. But TINY_SHMEM had
already been removed in v2.6.29. So this optional dependency can safely
be removed too.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of error, the function anon_inode_getfile() returns
ERR_PTR() and never returns NULL. The NULL test in the return
value check should be replaced with IS_ERR().
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Android's shared memory subsystem, Ashmem, does not support calls from a
32bit userspace in a 64 bit kernel. This patch adds support for syscalls
coming from a 32bit userspace in a 64bit kernel.
The patch has been successfully tested on ARMv8 AEM(64bit
platform model) and Versatile Express A9(32bit platform).
v2: Fix missing compat.h include.
Signed-off-by: Serban Constantinescu <serban.constantinescu@arm.com>
Acked-by: Arve Hjønnevåg <arve@android.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Modify the kernel logger to record the UID associated with
the log entries. Always allow the same UID which generated a
log message to read the log message.
Allow anyone in the logs group, or anyone with CAP_SYSLOG, to
read all log entries.
In addition, allow the client to upgrade log formats, so they
can get additional information from the kernel.
Cc: Android Kernel Team <kernel-team@android.com>
Cc: Nick Kralevich <nnk@google.com>
Signed-off-by: Nick Kralevich <nnk@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Problem:
There exists a path in ashmem driver that could lead to acquistion
of mm->mmap_sem, ashmem_mutex in reverse order. This could lead
to deadlock in the system.
For Example, assume that mmap is called on a ashmem region
in the context of a thread say T1.
sys_mmap_pgoff (1. acquires mm->mmap_sem)
|
--> mmap_region
|
----> ashmem_mmap (2. acquires asmem_mutex)
Now if there is a context switch after 1 and before 2,
and if another thread T2 (that shares the mm struct) invokes an
ioctl say ASHMEM_GET_NAME, this can lead to the following path
ashmem_ioctl
|
-->get_name (3. acquires ashmem_mutex)
|
---> copy_to_user (4. acquires the mm->mmap_sem)
Note that the copy_to_user could lead to a valid fault if no
physical page is allocated yet for the user address passed.
Now T1 has mmap_sem and is waiting for ashmem_mutex.
and T2 has the ashmem_mutex and is waiting for mmap_sem
Thus leading to deadlock.
Solution:
Do not call copy_to_user or copy_from_user while holding the
ahsmem_mutex. Instead copy this to a local buffer that lives
in the stack while holding this lock. This will maintain data
integrity as well never reverse the lock order.
Testing:
Created a unit test case to reproduce the problem.
Used the same to test this fix on kernel version 3.4.0
Ported the same patch to 3.8
Signed-off-by: Shankar Brahadeeswaran <shankoo77@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
