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>

1 files changed, 5 insertions, 0 deletions

diff --git a/sound/core/control.c b/sound/core/control.c
index 439ce64f9d82..070aab490191 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -50,6 +50,10 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
         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 @@ static const struct file_operations snd_ctl_f_ops =
         .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,