[media] staging/lirc: fix mem leaks and ptr err usage

When the lirc drivers were converted over to using memdup_user, I
mistakenly also removed corresponding calls to kfree. Add those back. I
also screwed up on the allocation error check in lirc_serial, using if
(PTR_ERR()) instead of if (IS_ERR()), which broke transmit.

Reported-by: Jiri Fojtasek <jiri.fojtasek@hlohovec.net>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/lirc/lirc_imon.c

@@ -447,6 +447,7 @@ static ssize_t vfd_write(struct file *file, const char *buf,
 
 exit:
 	mutex_unlock(&context->ctx_lock);
+	kfree(data_buf);
 
 	return (!retval) ? n_bytes : retval;
 }

drivers/staging/lirc/lirc_it87.c

@@ -232,6 +232,7 @@ static ssize_t lirc_write(struct file *file, const char *buf,
 		i++;
 	}
 	terminate_send(tx_buf[i - 1]);
+	kfree(tx_buf);
 	return n;
 }
 

drivers/staging/lirc/lirc_parallel.c

@@ -376,6 +376,7 @@ static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,
 	unsigned long flags;
 	int counttimer;
 	int *wbuf;
+	ssize_t ret;
 
 	if (!is_claimed)
 		return -EBUSY;
@@ -393,8 +394,10 @@ static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,
 	if (timer == 0) {
 		/* try again if device is ready */
 		timer = init_lirc_timer();
-		if (timer == 0)
+		if (timer == 0) {
-			return -EIO;
+			ret = -EIO;
+			goto out;
+		}
 	}
 
 	/* adjust values from usecs */
@@ -420,7 +423,8 @@ static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,
 			if (check_pselecd && (in(1) & LP_PSELECD)) {
 				lirc_off();
 				local_irq_restore(flags);
-				return -EIO;
+				ret = -EIO;
+				goto out;
 			}
 		} while (counttimer < wbuf[i]);
 		i++;
@@ -436,7 +440,8 @@ static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,
 			level = newlevel;
 			if (check_pselecd && (in(1) & LP_PSELECD)) {
 				local_irq_restore(flags);
-				return -EIO;
+				ret = -EIO;
+				goto out;
 			}
 		} while (counttimer < wbuf[i]);
 		i++;
@@ -445,7 +450,11 @@ static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,
 #else
 	/* place code that handles write without external timer here */
 #endif
-	return n;
+	ret = n;
+out:
+	kfree(wbuf);
+
+	return ret;
 }
 
 static unsigned int lirc_poll(struct file *file, poll_table *wait)

drivers/staging/lirc/lirc_sasem.c

@@ -448,6 +448,7 @@ static ssize_t vfd_write(struct file *file, const char *buf,
 exit:
 
 	mutex_unlock(&context->ctx_lock);
+	kfree(data_buf);
 
 	return (!retval) ? n_bytes : retval;
 }

drivers/staging/lirc/lirc_serial.c

@@ -966,7 +966,7 @@ static ssize_t lirc_write(struct file *file, const char *buf,
 	if (n % sizeof(int) || count % 2 == 0)
 		return -EINVAL;
 	wbuf = memdup_user(buf, n);
-	if (PTR_ERR(wbuf))
+	if (IS_ERR(wbuf))
 		return PTR_ERR(wbuf);
 	spin_lock_irqsave(&hardware[type].lock, flags);
 	if (type == LIRC_IRDEO) {
@@ -981,6 +981,7 @@ static ssize_t lirc_write(struct file *file, const char *buf,
 	}
 	off();
 	spin_unlock_irqrestore(&hardware[type].lock, flags);
+	kfree(wbuf);
 	return n;
 }
 

drivers/staging/lirc/lirc_sir.c

@@ -330,6 +330,7 @@ static ssize_t lirc_write(struct file *file, const char *buf, size_t n,
 	/* enable receiver */
 	Ser2UTCR3 = UTCR3_RXE|UTCR3_RIE;
 #endif
+	kfree(tx_buf);
 	return count;
 }