ALSA: core - Define llseek fops
Set no_llseek to llseek file ops of each sound component (but for hwdep).
This avoids the implicit BKL invocation via generic_file_llseek() used
as default when fops.llseek is NULL.
Also call nonseekable_open() at each open ops to ensure the file flags
have no seek bit.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/control.c b/sound/core/control.c
index 439ce64..070aab4 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -50,6 +50,10 @@
struct snd_ctl_file *ctl;
int err;
+ err = nonseekable_open(inode, file);
+ if (err < 0)
+ return err;
+
card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
if (!card) {
err = -ENODEV;
@@ -1388,6 +1392,7 @@
.read = snd_ctl_read,
.open = snd_ctl_open,
.release = snd_ctl_release,
+ .llseek = no_llseek,
.poll = snd_ctl_poll,
.unlocked_ioctl = snd_ctl_ioctl,
.compat_ioctl = snd_ctl_ioctl_compat,