Commit graph

5 commits

Author SHA1 Message Date
Julia Lawall 22511cfa7d [media] usb: constify snd_pcm_ops structures
Check for snd_pcm_ops structures that are only stored in the ops field of a
snd_soc_platform_driver structure or passed as the third argument to
snd_pcm_set_ops.  The corresponding field or parameter is declared const,
so snd_pcm_ops structures that have this property can be declared as const
also.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct snd_pcm_ops i@p = { ... };

@ok1@
identifier r.i;
struct snd_soc_platform_driver e;
position p;
@@
e.ops = &i@p;

@ok2@
identifier r.i;
expression e1, e2;
position p;
@@
snd_pcm_set_ops(e1, e2, &i@p)

@bad@
position p != {r.p,ok1.p,ok2.p};
identifier r.i;
struct snd_pcm_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct snd_pcm_ops i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-09-19 16:19:10 -03:00
Matthew Leach 2a00932f08 [media] media: usbtv: prevent access to free'd resources
When disconnecting the usbtv device, the sound card is unregistered
from ALSA and the snd member of the usbtv struct is set to NULL.  If
the usbtv snd_trigger work is running, this can cause a race condition
where the kernel will attempt to access free'd resources, shown in
[1].

This patch fixes the disconnection code by cancelling any snd_trigger
work before unregistering the sound card from ALSA and checking that
the snd member still exists in the work function.

[1]:
 usb 3-1.2: USB disconnect, device number 6
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: [<ffffffff81093850>] process_one_work+0x30/0x480
 PGD 405bbf067 PUD 405bbe067 PMD 0
 Call Trace:
  [<ffffffff81093ce8>] worker_thread+0x48/0x4e0
  [<ffffffff81093ca0>] ? process_one_work+0x480/0x480
  [<ffffffff81093ca0>] ? process_one_work+0x480/0x480
  [<ffffffff81099998>] kthread+0xd8/0xf0
  [<ffffffff815c73c2>] ret_from_fork+0x22/0x40
  [<ffffffff810998c0>] ? kthread_worker_fn+0x170/0x170
 ---[ end trace 0f3dac5c1a38e610 ]---

Signed-off-by: Matthew Leach <matthew@mattleach.net>
Tested-by: Peter Sutton <foxxy@foxdogstudios.com>
Cc: stable@vger.kernel.org
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-12 13:31:08 -03:00
Lubomir Rintel 5ae1e2b24f [media] usbtv: clarify the licensing
OpenBSD would like to reuse some code but consider the licensing not
clear enough. Let's clarify it a bit so that it suits their conventions:

1.) Keep the "extra text" away from the copyright statement and the
rights grant.

2.) Add the warranty disclaimer -- it should not be legally required,
nevertheless the clause 1. of the rights grant refest to it.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Federico Simoncelli <fsimonce@redhat.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-08 16:16:57 -03:00
Amber Thrall 146af9cb80 [media] Media: USB: usbtv: Fixed all coding style issues in usbtv source files
Fixed various coding styles, ignoring coding style error on line 5 for all files containing a link that is longer than 80 characters long.

Signed-off-by: Amber Thrall <amber.rose.thrall@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2014-09-23 16:13:44 -03:00
Federico Simoncelli 63ddf68de5 [media] usbtv: add audio support
Add an ALSA handler inside usbtv module, in order to make
audio to work with those devices.

Signed-off-by: Federico Simoncelli <fsimonce@redhat.com>
Tested-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2014-08-21 15:25:34 -05:00