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, 0 insertions, 12 deletions

diff --git a/sound/pci/mixart/mixart.c b/sound/pci/mixart/mixart.c
index b5df78b..be95e00 100644
--- a/sound/pci/mixart/mixart.c
+++ b/sound/pci/mixart/mixart.c
@@ -1161,13 +1161,7 @@ static ssize_t snd_mixart_BA0_read(struct snd_info_entry *entry,
 				   size_t count, loff_t pos)
 {
 	struct mixart_mgr *mgr = entry->private_data;
-	unsigned long maxsize;
 
-	if (pos >= MIXART_BA0_SIZE)
-		return 0;
-	maxsize = MIXART_BA0_SIZE - pos;
-	if (count > maxsize)
-		count = maxsize;
 	count = count & ~3; /* make sure the read size is a multiple of 4 bytes */
 	if (copy_to_user_fromio(buf, MIXART_MEM(mgr, pos), count))
 		return -EFAULT;
@@ -1183,13 +1177,7 @@ static ssize_t snd_mixart_BA1_read(struct snd_info_entry *entry,
 				   size_t count, loff_t pos)
 {
 	struct mixart_mgr *mgr = entry->private_data;
-	unsigned long maxsize;
 
-	if (pos > MIXART_BA1_SIZE)
-		return 0;
-	maxsize = MIXART_BA1_SIZE - pos;
-	if (count > maxsize)
-		count = maxsize;
 	count = count & ~3; /* make sure the read size is a multiple of 4 bytes */
 	if (copy_to_user_fromio(buf, MIXART_REG(mgr, pos), count))
 		return -EFAULT;