linux-stable.git/include/media, branch linux-3.16.y

media: fix media devnode ioctl/syscall and unregister race

2020-04-28T18:03:51+00:00

commit 6f0dd24a084a17f9984dd49dffbf7055bf123993 upstream.

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)

Signed-off-by: Shuah Khan 
Suggested-by: Sakari Ailus 
Reported-by: Mauro Carvalho Chehab 
Tested-by: Mauro Carvalho Chehab 
Signed-off-by: Mauro Carvalho Chehab 
[bwh: Backported to 3.16: adjut filename, context]
Signed-off-by: Ben Hutchings

media-device: dynamically allocate struct media_devnode

2020-04-28T18:03:50+00:00

commit a087ce704b802becbb4b0f2a20f2cb3f6911802e upstream.

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.

Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Mauro Carvalho Chehab 
[bwh: Backported to 3.16:
 - Drop change in au0828
 - Include  in media-device.c
 - Adjust context]
Signed-off-by: Ben Hutchings

media-devnode: fix namespace mess

2020-04-28T18:03:49+00:00

commit 163f1e93e995048b894c5fc86a6034d16beed740 upstream.

Along all media controller code, "mdev" is used to represent
a pointer to struct media_device, and "devnode" for a pointer
to struct media_devnode.

However, inside media-devnode.[ch], "mdev" is used to represent
a pointer to struct media_devnode.

This is very confusing and may lead to development errors.

So, let's change all occurrences at media-devnode.[ch] to
also use "devnode" for such pointers.

This patch doesn't make any functional changes.

Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Mauro Carvalho Chehab 
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings

media: davinci/vpbe: array underflow in vpbe_enum_outputs()

2019-09-23T20:12:02+00:00

commit b72845ee5577b227131b1fef23f9d9a296621d7b upstream.

In vpbe_enum_outputs() we check if (temp_index >= cfg->num_outputs) but
the problem is that "temp_index" can be negative.  This patch changes
the types to unsigned to address this array underflow bug.

Fixes: 66715cdc3224 ("[media] davinci vpbe: VPBE display driver")

Signed-off-by: Dan Carpenter 
Acked-by: "Lad, Prabhakar" 
Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Ben Hutchings

media: v4l: event: Prevent freeing event subscriptions while accessed

2018-11-20T18:05:57+00:00

commit ad608fbcf166fec809e402d548761768f602702c upstream.

The event subscriptions are added to the subscribed event list while
holding a spinlock, but that lock is subsequently released while still
accessing the subscription object. This makes it possible to unsubscribe
the event --- and freeing the subscription object's memory --- while
the subscription object is simultaneously accessed.

Prevent this by adding a mutex to serialise the event subscription and
unsubscription. This also gives a guarantee to the callback ops that the
add op has returned before the del op is called.

This change also results in making the elems field less special:
subscriptions are only added to the event list once they are fully
initialised.

Signed-off-by: Sakari Ailus 
Reviewed-by: Hans Verkuil 
Reviewed-by: Laurent Pinchart 
Fixes: c3b5b0241f62 ("V4L/DVB: V4L: Events: Add backend")
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Ben Hutchings

media: platform: davinci: drop VPFE_CMD_S_CCDC_RAW_PARAMS

2018-11-20T18:04:46+00:00

commit d75cf0144f150272be806b69b4e62553ba07ea1b upstream.

drop VPFE_CMD_S_CCDC_RAW_PARAMS ioctl from dm355/dm644x following reasons:

- This ioctl was never in public api and was only defined in kernel header.
- The function set_params constantly mixes up pointers and phys_addr_t
  numbers.
- This is part of a 'VPFE_CMD_S_CCDC_RAW_PARAMS' ioctl command that is
  described as an 'experimental ioctl that will change in future kernels'.
- The code to allocate the table never gets called after we copy_from_user
  the user input over the kernel settings, and then compare them
  for inequality.
- We then go on to use an address provided by user space as both the
  __user pointer for input and pass it through phys_to_virt to come up
  with a kernel pointer to copy the data to. This looks like a trivially
  exploitable root hole.

Signed-off-by: Lad, Prabhakar 
Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab 
[bwh: Backported to 3.16: deleted code was slightly different]
Signed-off-by: Ben Hutchings

media: vb2: fix VBI/poll regression

2014-10-09T19:23:49+00:00

commit 58d75f4b1ce26324b4d809b18f94819843a98731 upstream.

The recent conversion of saa7134 to vb2 unconvered a poll() bug that
broke the teletext applications alevt and mtt. These applications
expect that calling poll() without having called VIDIOC_STREAMON will
cause poll() to return POLLERR. That did not happen in vb2.

This patch fixes that behavior. It also fixes what should happen when
poll() is called when STREAMON is called but no buffers have been
queued. In that case poll() will also return POLLERR, but only for
capture queues since output queues will always return POLLOUT
anyway in that situation.

This brings the vb2 behavior in line with the old videobuf behavior.

Signed-off-by: Hans Verkuil 
Acked-by: Laurent Pinchart 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'topic/omap3isp' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

2014-06-13T06:04:28+00:00

Pull OMAP3 updates from Mauro Carvalho Chehab:
 "Some driver improvements on OMAP3.  This series depend on some iommu
  patches already merged"

* 'topic/omap3isp' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (26 commits)
  [media] omap3isp: Rename isp_buffer isp_addr field to dma
  [media] omap3isp: Move to videobuf2
  [media] v4l: vb2: Add a function to discard all DONE buffers
  [media] omap3isp: Cancel all queued buffers when stopping the video stream
  [media] omap3isp: Move buffer irqlist to isp_buffer structure
  [media] omap3isp: Move queue irqlock to isp_video structure
  [media] omap3isp: Move queue mutex to isp_video structure
  [media] omap3isp: queue: Don't build scatterlist for kernel buffer
  [media] omap3isp: Use the ARM DMA IOMMU-aware operations
  [media] omap3isp: queue: Use sg_alloc_table_from_pages()
  [media] omap3isp: queue: Map PFNMAP buffers to device
  [media] omap3isp: queue: Fix the dma_map_sg() return value check
  [media] omap3isp: queue: Allocate kernel buffers with dma_alloc_coherent
  [media] omap3isp: queue: Inline the ispmmu_v(un)map functions
  [media] omap3isp: queue: Merge the prepare and sglist functions
  [media] omap3isp: queue: Use sg_table structure
  [media] omap3isp: queue: Move IOMMU handling code to the queue
  [media] omap3isp: video: Set the buffer bytesused field at completion time
  [media] omap3isp: ccdc: Use the DMA API for FPC
  [media] omap3isp: ccdc: Use the DMA API for LSC
  ...

[media] adv7604: Add LLC polarity configuration

2014-05-25T16:10:16+00:00

Add an inv_llc_pol field to platform data to control the clock polarity.

Signed-off-by: Laurent Pinchart 
Reviewed-by: Hans Verkuil 
Reviewed-by: Sylwester Nawrocki 
Signed-off-by: Mauro Carvalho Chehab

[media] adv7604: Specify the default input through platform data

2014-05-25T16:03:02+00:00

And set input routing when initializing the device.

Signed-off-by: Laurent Pinchart 
Reviewed-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab