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, 6 insertions, 0 deletions

diff --git a/sound/core/timer.c b/sound/core/timer.c
index 73943651caed..8c9a661df05b 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1237,6 +1237,11 @@ static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
 static int snd_timer_user_open(struct inode *inode, struct file *file)
 {
         struct snd_timer_user *tu;
+        int err;
+
+        err = nonseekable_open(inode, file);
+        if (err < 0)
+                return err;
 
         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
         if (tu == NULL)
@@ -1921,6 +1926,7 @@ static const struct file_operations snd_timer_f_ops =
         .read =         snd_timer_user_read,
         .open =         snd_timer_user_open,
         .release =      snd_timer_user_release,
+        .llseek =       no_llseek,
         .poll =         snd_timer_user_poll,
         .unlocked_ioctl =       snd_timer_user_ioctl,
         .compat_ioctl = snd_timer_user_ioctl_compat,