This auto-generated file is bogus: it just adds a toc for two
other files. Instead, just move the controls and extended-controls
directly to the common file.
this avoids a blank page, and better organize the document.
As VIDIOC_G_foo is the reference used for VIDIOC_S_foo and
VIDIOC_TRY_foo, we need to explicitly name the reference, as
otherwise, it will mention the three ioctls altogether, with
is not what we want.
doc-rst: linux_tv: Replace reference names to match ioctls
Due to a limitation at the DocBook language, the references
were using lowercase and slashes, instead of the name of the
ioctls. On ReST, make them identical. This will hopefully
help to cleanup the code a little bit.
The Video4Linux documentation is big. We want to numerate the
items, as it makes easier to reference an item while discussing
the document on meetings.
Merge branch 'docs-next' of git://git.lwn.net/linux into devel/docs-next
* 'docs-next' of git://git.lwn.net/linux: (64 commits)
Add .pyc files to .gitignore
Doc: PM: Fix a typo in intel_powerclamp.txt
doc-rst: flat-table directive - initial implementation
Documentation: add meta-documentation for Sphinx and kernel-doc
Documentation: tiny typo fix in usb/gadget_multi.txt
Documentation: fix wrong value in md.txt
bcache: documentation formatting, edited for clarity, stripe alignment notes
bcache: documentation updates and corrections
Documentation: add top level 'make help' output for Sphinx
Documentation/sphinx: drop modindex, we don't have python modules
Documentation/sphinx: add support for specifying extra export files
Documentation/sphinx: use a more sensible string split in kernel-doc extension
Documentation/sphinx: remove unnecessary temporary variable
kernel-doc: unify all EXPORT_SYMBOL scanning to one place
kernel-doc: add support for specifying extra files for EXPORT_SYMBOLs
kernel-doc: abstract filename mapping
kernel-doc: add missing semi-colons in option parsing
kernel-doc: do not warn about duplicate default section names
kernel-doc: remove old debug cruft from dump_section()
docs: kernel-doc: Add "example" and "note" to the magic section types
...
The ``flat-table`` is a double-stage list similar to the ``list-table`` with
some additional features:
* column-span: with the role ``cspan`` a cell can be extended through
additional columns
* row-span: with the role ``rspan`` a cell can be extended through
additional rows
* auto span rightmost cell of a table row over the missing cells on the right
side of that table-row. With Option ``:fill-cells:`` this behavior can
changed from *auto span* to *auto fill*, which automaticly inserts (empty)
list tables
The *list tables* formats are double stage lists. Compared to the
ASCII-art they migth be less comfortable for readers of the
text-files. Their advantage is, that they are easy to create/modify
and that the diff of a modification is much more meaningfull, because
it is limited to the modified content.
The initial implementation was taken from the sphkerneldoc project [1]
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
[jc: fixed typos and misspellings in the docs] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Laurent Pinchart [Wed, 15 Jun 2016 23:27:58 +0000 (20:27 -0300)]
[media] videodev2.h: Group YUV 3 planes formats together
The formats are interleaved with the YUV packed and miscellaneous
formats, making the result confusing especially with the YUV444 format
being packed and not planar like YUV410 or YUV420. Move them to their
own group as the 2 planes or 3 non-contiguous planes formats to clarify
the header.
Add detection of source pad number for drivers aware of the media controller
API, so that rcar-vin can create device nodes to support modern drivers such
as adv7604.c (for HDMI on Lager) and the converted adv7180.c (for composite)
underneath.
Building rcar_vin gains a dependency on CONFIG_MEDIA_CONTROLLER, in
line with requirements for building the drivers associated with it.
Signed-off-by: William Towle <william.towle@codethink.co.uk> Signed-off-by: Rob Taylor <rob.taylor@codethink.co.uk>
[ulrich.hecht+renesas@gmail.com: adapted to rcar-vin rewrite] Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Laurent Pinchart [Tue, 24 May 2016 11:53:39 +0000 (08:53 -0300)]
[media] adv7604: Don't ignore pad number in subdev DV timings pad operations
The dv_timings_cap() and enum_dv_timings() pad operations take a pad
number as an input argument and return the DV timings capabilities and
list of supported DV timings for that pad.
Commit bd3e275f3ec0 ("[media] media: i2c: adv7604: Use v4l2-dv-timings
helpers") broke this as it started ignoring the pad number, always
returning the information associated with the currently selected input.
Fix it.
Markus Pargmann [Mon, 14 Dec 2015 14:41:53 +0000 (12:41 -0200)]
[media] v4l: mt9v032: Add V4L2 controls for AEC and AGC
This patch adds V4L2 controls for Auto Exposure Control and Auto Gain
Control settings. These settings include low pass filter, update
frequency of these settings and the update interval for those units.
[Avoid forward declarations]
[Fix 80 columns limit violation]
[Rename controls to avoid underscores in names]
[Fix the AEC maximum shutter width on MT9V032]
Markus Pargmann [Mon, 14 Dec 2015 14:41:52 +0000 (12:41 -0200)]
[media] v4l: mt9v032: Do not unset master_mode
The power_on function of the driver resets the chip and sets the
CHIP_CONTROL register to 0. This switches the operating mode to slave.
The s_stream function sets the correct mode. But this caused problems on
a board where the camera chip is operated as master. The camera started
after a random amount of time streaming an image, I observed between 10
and 300 seconds.
The STRFM_OUT and STLN_OUT pins are not connected on this board which
may cause some issues in slave mode. I could not find any documentation
about this.
Keeping the chip in master mode after the reset helped to fix this
issue for me.
Axel Lin [Sun, 10 Aug 2014 09:41:49 +0000 (06:41 -0300)]
[media] v4l: mt9v032: Remove duplicate test for I2C_FUNC_SMBUS_WORD_DATA functionality
Since commit b42261078a91 ("regmap: i2c: fallback to SMBus if the adapter
does not support standard I2C"), regmap-i2c will check the
I2C_FUNC_SMBUS_[BYTE|WORD]_DATA functionality based on the regmap_config
setting if the adapter does not support standard I2C.
So remove the I2C_FUNC_SMBUS_WORD_DATA functionality check in the driver code.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Ezequiel Garcia [Sat, 4 Jun 2016 23:47:20 +0000 (20:47 -0300)]
[media] tw686x: audio: Prevent hw param changes while busy
Audio hw params are shared across all DMA channels,
so if the user changes any of these while any DMA channel is
enabled, it will impact the enabled channels, potentially causing
serious instability issues.
This commit avoids such situation, by preventing any hw param
change (on any DMA channel) if any other DMA audio channel is capturing.
Ezequiel Garcia [Sat, 4 Jun 2016 23:47:19 +0000 (20:47 -0300)]
[media] tw686x: audio: Allow to configure the period size
Currently, the driver has a fixed period size of 4096 bytes
(2048 frames). Since this hardware can configure the audio
capture size, this commit allows a period size range of [512-4096].
Now that we've introduced the dma_mode parameter to pick the
DMA operation, let's use it to also select the audio DMA
operation.
When dma_mode != memcpy, the driver will avoid using memcpy
in the audio capture path, and the DMA hardware operation
will act directly on the ALSA buffers.
Ezequiel Garcia [Sat, 4 Jun 2016 23:47:16 +0000 (20:47 -0300)]
[media] tw686x: Add support for DMA contiguous interlaced frame mode
Now that the driver has the infrastructure to support more
DMA modes, let's add the DMA contiguous interlaced frame mode.
In this mode, the DMA P and B buffers are programmed with
the user-provided buffers. When a P (or B) frame is ready,
a new buffer is dequeued into P (or B).
In addition to interlaced fields, the device can also be
programmed to deliver alternate fields. Only interlaced
mode is supported for now.
Tested-by: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Ezequiel Garcia [Sat, 4 Jun 2016 23:47:15 +0000 (20:47 -0300)]
[media] tw686x: Introduce an interface to support multiple DMA modes
Let's set the corner stone to support all the DMA modes
available on this device.
For stability reasons, the driver is currently setting DMA frame
mode, and using single DMA buffers to get the P and B buffers.
Each frame is then memcpy'ed into the user buffer.
However, other platforms might be interested in avoiding this
memcpy, or in taking advantage of the chip's DMA scatter-gather
capabilities.
To achieve this, this commit introduces a "dma_mode" module parameter,
and a tw686x_dma_ops struct. This will allow to define functions to
alloc/free DMA buffers, and to return the frames to userspace.
The memcpy-based method described above is named as dma_mode="memcpy".
Current alloc/free functions are renamed as tw686x_memcpy_xxx,
and are now used through a memcpy_dma_ops.
Tested-by: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Those structs are used only at bdisp-hw, so they shouldn't be
there in a header file that it is used elsewhere.
This fixes the following Gcc 6.1 warnings:
In file included from drivers/media/platform/sti/bdisp/bdisp-debug.c:11:0:
drivers/media/platform/sti/bdisp/bdisp-filter.h:207:65: warning: ‘bdisp_v_spec’ defined but not used [-Wunused-const-variable=]
static const struct __maybe_unused bdisp_filter_v_spec bdisp_v_spec[] = {
^~~~~~~~~
In file included from drivers/media/platform/sti/bdisp/bdisp-debug.c:11:0:
drivers/media/platform/sti/bdisp/bdisp-filter.h:23:65: warning: ‘bdisp_h_spec’ defined but not used [-Wunused-const-variable=]
static const struct __maybe_unused bdisp_filter_h_spec bdisp_h_spec[] = {
^~~~~~~~~
drivers/media/i2c/adv7842.c:2400:27: warning: 'prim_mode_txt' defined but not used [-Wunused-const-variable=]
static const char * const prim_mode_txt[] = {
^~~~~~~~~~~~~
That seems to be useful for debug, and likely were used before.
While we could simply remove, let's comment it out, for now.
drivers/media/usb/em28xx/em28xx-dvb.c:907:38: warning: 'pctv_461e_m88ds3103_config' defined but not used [-Wunused-const-variable=]
static const struct m88ds3103_config pctv_461e_m88ds3103_config = {
^~~~~~~~~~~~~~~~~~~~~~~~~~
That's a left over of patch 76b91be3d360a ('em28xx: PCTV 461e use I2C
client for demod and SEC').
Gcc 6.1 warns about some unused vars. Remove them:
drivers/media/platform/vivid/vivid-vid-cap.c:40:2: warning: 'tpf_default' defined but not used [-Wunused-const-variable=]
tpf_default = {.numerator = 1, .denominator = 30};
^~~~~~~~~~~
drivers/media/platform/vivid/vivid-sdr-cap.c:54:27: warning: 'NUM_FORMATS' defined but not used [-Wunused-const-variable=]
static const unsigned int NUM_FORMATS = ARRAY_SIZE(formats);
^~~~~~~~~~~
drivers/media/pci/zoran/zr36016.c:251:18: warning: 'zr016_yoff' defined but not used [-Wunused-const-variable=]
static const int zr016_yoff[] = { 8, 9, 7 };
^~~~~~~~~~
drivers/media/pci/zoran/zr36016.c:250:18: warning: 'zr016_xoff' defined but not used [-Wunused-const-variable=]
static const int zr016_xoff[] = { 20, 20, 20 };
^~~~~~~~~~
Those tables aren't used anywere. So, remove them.
As Gcc6.1 warned, those tables are currently unused:
drivers/media/tuners/r820t.c:349:18: warning: 'r820t_mixer_gain_steps' defined but not used [-Wunused-const-variable=]
static const int r820t_mixer_gain_steps[] = {
^~~~~~~~~~~~~~~~~~~~~~
drivers/media/tuners/r820t.c:345:18: warning: 'r820t_lna_gain_steps' defined but not used [-Wunused-const-variable=]
static const int r820t_lna_gain_steps[] = {
^~~~~~~~~~~~~~~~~~~~
They're actually used only by a routine that it is currently
commented out. So, move those tables to be together with such
code and comment them out.
Those tables are currently unused, so comment them out:
drivers/media/dvb-frontends/dib0090.c:852:18: warning: 'rf_ramp_pwm_sband' defined but not used [-Wunused-const-variable=]
static const u16 rf_ramp_pwm_sband[] = {
^~~~~~~~~~~~~~~~~
drivers/media/dvb-frontends/dib0090.c:800:18: warning: 'bb_ramp_pwm_boost' defined but not used [-Wunused-const-variable=]
static const u16 bb_ramp_pwm_boost[] = {
^~~~~~~~~~~~~~~~~
drxj: comment out the unused nicam_presc_table_val table
Avoid this warning:
drivers/media/dvb-frontends/drx39xyj/drxj.c:1243:18: warning: 'nicam_presc_table_val' defined but not used [-Wunused-const-variable=]
static const u16 nicam_presc_table_val[43] = {
^~~~~~~~~~~~~~~~~~~~~
The PCI device ID table is only used if compiled with modules
support. When compiled with modules disabled, this is now
producing this bogus warning:
drivers/media/pci/cx25821/cx25821-alsa.c:696:35: warning: 'cx25821_audio_pci_tbl' defined but not used [-Wunused-const-variable=]
static const struct pci_device_id cx25821_audio_pci_tbl[] = {
^~~~~~~~~~~~~~~~~~~~~
Fix it by annotating that the function may not be used.
The header file has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The header file has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The header file has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The header file has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The header file has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The mc5602_s5k4aa.h has some private static structures that
are used only by the C file. Move those structures to the C file,
in order to shut up gcc 6.1 warnings.
The mc5602_brigde.h is included at m5602 submodules. This
causes Gcc 6.1 to complain:
drivers/media/usb/gspca/m5602/m5602_bridge.h:124:28: warning: 'sensor_urb_skeleton' defined but not used [-Wunused-const-variable=]
static const unsigned char sensor_urb_skeleton[] = {
^~~~~~~~~~~~~~~~~~~
drivers/media/usb/gspca/m5602/m5602_bridge.h:119:28: warning: 'bridge_urb_skeleton' defined but not used [-Wunused-const-variable=]
static const unsigned char bridge_urb_skeleton[] = {
^~~~~~~~~~~~~~~~~~~
Let's shut up gcc 6.1 warnings by moving those data structures
to the core, as they're used only there.
drivers/media/pci/cx18/cx18-driver.h:497:18: warning: 'vbi_hblank_samples_50Hz' defined but not used [-Wunused-const-variable=]
static const u32 vbi_hblank_samples_50Hz = 284; /* 4 byte EAV + 280 anc/fill */
^~~~~~~~~~~~~~~~~~~~~~~
drivers/media/pci/cx18/cx18-driver.h:496:18: warning: 'vbi_hblank_samples_60Hz' defined but not used [-Wunused-const-variable=]
static const u32 vbi_hblank_samples_60Hz = 272; /* 4 byte EAV + 268 anc/fill */
^~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/media/pci/cx18/cx18-cards.c:25:0:
drivers/media/pci/cx18/cx18-driver.h:497:18: warning: 'vbi_hblank_samples_50Hz' defined but not used [-Wunused-const-variable=]
static const u32 vbi_hblank_samples_50Hz = 284; /* 4 byte EAV + 280 anc/fill */
^~~~~~~~~~~~~~~~~~~~~~~
drivers/media/pci/cx18/cx18-driver.h:496:18: warning: 'vbi_hblank_samples_60Hz' defined but not used [-Wunused-const-variable=]
static const u32 vbi_hblank_samples_60Hz = 272; /* 4 byte EAV + 268 anc/fill */
^~~~~~~~~~~~~~~~~~~~~~~
drivers/media/pci/cx18/cx18-driver.h:495:18: warning: 'vbi_active_samples' defined but not used [-Wunused-const-variable=]
static const u32 vbi_active_samples = 1444; /* 4 byte SAV + 720 Y + 720 U/V */
^~~~~~~~~~~~~~~~~~
In this specific case, this is somewhat intentional, as those
values are actually used in parts of the driver. The code assumes
that gcc optimizer it and not actually create any var, but convert
it to immediate access at the routines.
Yet, as we want to shut up gcc warnings, let's use #define, with
is the standard way to store values that will use assembler's
immediate access code.
Gcc 6.1 warns about some unused vars and functions. Remove them:
drivers/media/platform/exynos4-is/mipi-csis.c:665:46: warning: 's5pcsis_sd_internal_ops' defined but not used [-Wunused-const-variable=]
static const struct v4l2_subdev_internal_ops s5pcsis_sd_internal_ops = {
^~~~~~~~~~~~~~~~~~~~~~~
drivers/media/platform/exynos4-is/mipi-csis.c:652:12: warning: 's5pcsis_open' defined but not used [-Wunused-function]
static int s5pcsis_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
^~~~~~~~~~~~
Gcc 6.1 warns about some unused vars. Remove them:
drivers/media/usb/usbvision/usbvision-core.c:94:18: warning: 'min_imgheight' defined but not used [-Wunused-const-variable=]
static const int min_imgheight = MIN_FRAME_HEIGHT;
^~~~~~~~~~~~~
drivers/media/usb/usbvision/usbvision-core.c:93:18: warning: 'min_imgwidth' defined but not used [-Wunused-const-variable=]
static const int min_imgwidth = MIN_FRAME_WIDTH;
^~~~~~~~~~~~
drivers/media/usb/usbvision/usbvision-core.c:92:18: warning: 'max_imgheight' defined but not used [-Wunused-const-variable=]
static const int max_imgheight = MAX_FRAME_HEIGHT;
^~~~~~~~~~~~~
drivers/media/usb/usbvision/usbvision-core.c:91:18: warning: 'max_imgwidth' defined but not used [-Wunused-const-variable=]
static const int max_imgwidth = MAX_FRAME_WIDTH;
^~~~~~~~~~~~
Tiezhu Yang [Fri, 17 Jun 2016 01:40:02 +0000 (09:40 +0800)]
Documentation: fix wrong value in md.txt
In the current Documentation/md.txt, the lower limit value of
stripe_cache_size is 16 and the default value is 128, but when
I update kernel to the latest mainline version and RAID5 array
is created by mdadm, then execute the following commands, it
shows an error and a difference respectively.
1) set stripe_cache_size to 16
[root@localhost ~]# echo 16 > /sys/block/md0/md/stripe_cache_size
bash: echo: write error: Invalid argument
2) read the default value of stripe_cache_size
[root@localhost ~]# cat /sys/block/md0/md/stripe_cache_size
256
I read drivers/md/raid5.c and find the following related code:
1) in function 'raid5_set_cache_size':
if (size <= 16 || size > 32768)
return -EINVAL;
2) #define NR_STRIPES 256
So the lower limit value of stripe_cache_size should be 17 and
the default value should be 256.
Signed-off-by: Tiezhu Yang <kernelpatch@126.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Marc MERLIN [Sat, 12 Mar 2016 07:04:19 +0000 (23:04 -0800)]
bcache: documentation updates and corrections
Bcache documentation updates:
- Added new HOWTO/COOKBOOK section
- fixed a few typos
- /sys/block/bcache0/cache_mode is /sys/block/bcache0/bcache/cache_mode
Signed-off-by: Marc MERLIN <marc@merlins.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Two parameters were documented with a wrong name, and a struct
device pointer description was missing.
That caused the following warnings, when building documentation:
include/media/media-devnode.h:102: warning: No description found for parameter 'media_dev'
include/media/media-devnode.h:126: warning: No description found for parameter 'mdev'
include/media/media-devnode.h:126: warning: Excess function parameter 'media_dev' description in 'media_devnode_register'
Rename the description, to match the function parameter and fix
Documentation.
drivers/media/platform/rcar-vin/rcar-core.c: In function 'rvin_graph_notify_complete':
drivers/media/platform/rcar-vin/rcar-core.c:65:22: warning: variable 'sd' set but not used [-Wunused-but-set-variable]
struct v4l2_subdev *sd;
^
Sakari Ailus [Sun, 3 Apr 2016 19:31:03 +0000 (16:31 -0300)]
[media] videobuf2-v4l2: Verify planes array in buffer dequeueing
When a buffer is being dequeued using VIDIOC_DQBUF IOCTL, the exact buffer
which will be dequeued is not known until the buffer has been removed from
the queue. The number of planes is specific to a buffer, not to the queue.
This does lead to the situation where multi-plane buffers may be requested
and queued with n planes, but VIDIOC_DQBUF IOCTL may be passed an argument
struct with fewer planes.
__fill_v4l2_buffer() however uses the number of planes from the dequeued
videobuf2 buffer, overwriting kernel memory (the m.planes array allocated
in video_usercopy() in v4l2-ioctl.c) if the user provided fewer
planes than the dequeued buffer had. Oops!
Fixes: b0e0e1f83de3 ("[media] media: videobuf2: Prepare to divide videobuf2") Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Cc: stable@vger.kernel.org # for v4.4 and later Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Sakari Ailus [Wed, 11 May 2016 21:44:32 +0000 (18:44 -0300)]
[media] vb2: core: Skip planes array verification if pb is NULL
An earlier patch fixing an input validation issue introduced another
issue: vb2_core_dqbuf() is called with pb argument value NULL in some
cases, causing a NULL pointer dereference. Fix this by skipping the
verification as there's nothing to verify.
Fixes: e7e0c3e26587 ("[media] videobuf2-core: Check user space planes array in dqbuf") Signed-off-by: David R <david@unsolicited.net> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com> Cc: stable@vger.kernel.org # for v4.4 and later Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Shuah Khan [Fri, 10 Jun 2016 17:37:23 +0000 (14:37 -0300)]
[media] media: fix media devnode ioctl/syscall and unregister race
Media devnode open/ioctl could be in progress when media device unregister
is initiated. System calls and ioctls check media device registered status
at the beginning, however, there is a window where unregister could be in
progress without changing the media devnode status to unregistered.
process 1 process 2
fd = open(/dev/media0)
media_devnode_is_registered()
(returns true here)
media_device_unregister()
(unregister is in progress
and devnode isn't
unregistered yet)
...
ioctl(fd, ...)
__media_ioctl()
media_devnode_is_registered()
(returns true here)
...
media_devnode_unregister()
...
(driver releases the media device
memory)
media_device_ioctl()
(By this point
devnode->media_dev does not
point to allocated memory.
use-after free in in mutex_lock_nested)
BUG: KASAN: use-after-free in mutex_lock_nested+0x79c/0x800 at addr ffff8801ebe914f0
Fix it by clearing register bit when unregister starts to avoid the race.
process 1 process 2
fd = open(/dev/media0)
media_devnode_is_registered()
(could return true here)
media_device_unregister()
(clear the register bit,
then start unregister.)
...
ioctl(fd, ...)
__media_ioctl()
media_devnode_is_registered()
(return false here, ioctl
returns I/O error, and
will not access media
device memory)
...
media_devnode_unregister()
...
(driver releases the media device
memory)
Shuah Khan [Wed, 4 May 2016 19:48:28 +0000 (16:48 -0300)]
[media] media: fix use-after-free in cdev_put() when app exits after driver unbind
When driver unbinds while media_ioctl is in progress, cdev_put() fails with
when app exits after driver unbinds.
Add devnode struct device kobj as the cdev parent kobject. cdev_add() gets
a reference to it and releases it in cdev_del() ensuring that the devnode
is not deallocated as long as the application has the device file open.
media_devnode_register() initializes the struct device kobj before calling
cdev_add(). media_devnode_unregister() does cdev_del() and then deletes the
device. devnode is released when the last reference to the struct device is
gone.
This problem is found on uvcvideo, em28xx, and au0828 drivers and fix has
been tested on all three.
kernel: [ 193.599736] BUG: KASAN: use-after-free in cdev_put+0x4e/0x50
kernel: [ 193.599745] Read of size 8 by task media_device_te/1851
kernel: [ 193.599792] INFO: Allocated in __media_device_register+0x54
kernel: [ 193.599951] INFO: Freed in media_devnode_release+0xa4/0xc0
struct media_devnode is currently embedded at struct media_device.
While this works fine during normal usage, it leads to a race
condition during devnode unregister. the problem is that drivers
assume that, after calling media_device_unregister(), the struct
that contains media_device can be freed. This is not true, as it
can't be freed until userspace closes all opened /dev/media devnodes.
In other words, if the media devnode is still open, and media_device
gets freed, any call to an ioctl will make the core to try to access
struct media_device, with will cause an use-after-free and even GPF.
Fix this by dynamically allocating the struct media_devnode and only
freeing it when it is safe.
For the third time in three years, I'm changing my e-mail at
Samsung. That's bad, as it may stop communications with me for
a while. So, this time, I'll also the mchehab@kernel.org e-mail,
as it remains stable since ever.
Jani Nikula [Tue, 7 Jun 2016 09:13:56 +0000 (12:13 +0300)]
Documentation/sphinx: add support for specifying extra export files
Let the user specify file patterns where to look for the EXPORT_SYMBOLs
in addition to the file with kernel-doc comments. This is directly based
on the -export-file FILE option added to kernel-doc in "kernel-doc: add
support for specifying extra files for EXPORT_SYMBOLs", but we extend
that with globbing patterns in the Sphinx extension.
The file patterns are added as options to the :export: and :internal:
arguments of the kernel-doc directive. For example, to extract the
documentation of exported functions from include/net/mac80211.h:
Without the file pattern, no exported functions would be found, as the
EXPORT_SYMBOLs are placed in the various source files under
net/mac80211.
The matched files are also added as dependencies on the document in
Sphinx, as they may affect the output. This is one of the reasons to do
the globbing in the Sphinx extension instead of in scripts/kernel-doc.
The file pattern remains optional, and is not needed if the kernel-doc
comments and EXPORT_SYMBOLs are placed in the source file passed in as
the main argument to the kernel-doc directive. This is the most common
case across the kernel source tree.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Colin Ian King [Tue, 10 May 2016 05:40:22 +0000 (02:40 -0300)]
[media] m88rs2000: initialize status to zero
status is not initialized so it can contain garbage. The
check for status containing the FE_HAS_LOCK bit may randomly pass
or fail if the read of register 0x8c fails to set status after 25
read attempts. Fix this by initializing status to 0.
Issue found with CoverityScan, CID#986738
Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Jani Nikula [Tue, 7 Jun 2016 08:00:52 +0000 (11:00 +0300)]
kernel-doc: add support for specifying extra files for EXPORT_SYMBOLs
If the kernel-doc comments for functions are not in the same file as the
EXPORT_SYMBOL statements, the -export and -internal output selections do
not work as expected. This is typically the case when the kernel-doc
comments are in header files next to the function declarations and the
EXPORT_SYMBOL statements are next to the function definitions in the
source files.
Let the user specify additional source files in which to look for the
EXPORT_SYMBOLs using the new -export-file FILE option, which may be
given multiple times.
The pathological example for this is include/net/mac80211.h, which has
all the kernel-doc documentation for the exported functions defined in a
plethora of source files net/mac80211/*.c.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
kernel-doc: concatenate contents of colliding sections
we started getting (more) errors on duplicate section names, especially
on the default section name "Description":
include/net/mac80211.h:3174: warning: duplicate section name 'Description'
This is usually caused by a slightly unorthodox placement of parameter
descriptions, like in the above case, and kernel-doc resetting back to
the default section more than once within a kernel-doc comment.
Ignore warnings on the duplicate section name automatically assigned by
kernel-doc, and only consider explicitly user assigned duplicate section
names an issue.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Jonathan Corbet [Thu, 9 Jun 2016 19:35:05 +0000 (13:35 -0600)]
docs: kernel-doc: Add "example" and "note" to the magic section types
Lots of kerneldoc entries use "example:" or "note:" as section headers.
Until such a time as we can make them use proper markup, make them work as
intended.
Kees Cook [Wed, 18 May 2016 13:37:47 +0000 (06:37 -0700)]
docs: self-protection: rename "leak" to "exposure"
The meaning of "leak" can be both "untracked resource allocation" and
"memory content disclosure". This document's use was entirely of the
latter meaning, so avoid the confusion by using the Common Weakness
Enumeration name for this: Information Exposure (CWE-200). Additionally
adds a section on structure randomization.
Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Jonathan Corbet [Thu, 9 Jun 2016 19:17:11 +0000 (13:17 -0600)]
Merge branch 'sphinx-for-docs-next' into doc/4.8
Jani Nikula says:
Jon, this is v2 of [1] and [2], with a considerable amount of polish and
fixes added. We started dogfooding this within drm-intel, and Daniel has
reviewed the lot and contributed a number of fixes, most notably
accurate file and line number references from Sphinx build
errors/warnings to the kernel-doc comments in source code.
We believe this is now in good shape for merging for v4.8. It's all in
my sphinx-for-docs-next branch that you've already looked at; pull
details below.
When this lands in docs-next and we can backmerge to drm, we'll plunge
ahead and convert gpu.tmpl to rst, and have that ready for v4.8. We
think it's best to contribute that via the drm tree, as it'll involve
splitting up the documentation and likely numerous updates to kernel-doc
comments.
I plan to update Documentation/kernel-doc-nano-HOWTO.txt for Sphinx and
rst, obviously converting it to rst while at it.