ALSA: info - Check file position validity in common layer

Check the validity of the file position in the common info layer before
calling read or write callbacks in assumption that entry->size is set up
properly to indicate the max file size.

Removed the redundant checks from the callbacks as well.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 3 insertions, 9 deletions

diff --git a/sound/pci/cs46xx/cs46xx_lib.c b/sound/pci/cs46xx/cs46xx_lib.c
index 08117b142381..aad37082cb6e 100644
--- a/sound/pci/cs46xx/cs46xx_lib.c
+++ b/sound/pci/cs46xx/cs46xx_lib.c
@@ -2662,17 +2662,11 @@ static ssize_t snd_cs46xx_io_read(struct snd_info_entry *entry,
                                   struct file *file, char __user *buf,
                                   size_t count, loff_t pos)
 {
-        long size;
         struct snd_cs46xx_region *region = entry->private_data;
         
-        size = count;
-        if (pos + (size_t)size > region->size)
-                size = region->size - pos;
-        if (size > 0) {
-                if (copy_to_user_fromio(buf, region->remap_addr + pos, size))
-                        return -EFAULT;
-        }
-        return size;
+        if (copy_to_user_fromio(buf, region->remap_addr + pos, count))
+                return -EFAULT;
+        return count;
 }
 
 static struct snd_info_entry_ops snd_cs46xx_proc_io_ops = {