[alsa-devel] [PATCH 1/2] hda - fix ELD memory leak

[Wu Fengguang]

memset(eld) clears eld->proc_entry which will leak the struct
snd_info_entry when unloading the module.

Fix it by
- remove memset(eld)
- set eld->eld_valid to true _after_ all eld fields have been filled
- don't access the other eld fields when (eld->eld_valid == false)

Signed-off-by: Wu Fengguang <fengguang.wu at intel.com>
---
 sound/pci/hda/hda_eld.c    |    5 +----
 sound/pci/hda/patch_hdmi.c |   11 +++++------
 2 files changed, 6 insertions(+), 10 deletions(-)

--- linux.orig/sound/pci/hda/hda_eld.c	2011-11-15 21:02:25.000000000 +0800
+++ linux/sound/pci/hda/hda_eld.c	2011-11-15 21:13:46.000000000 +0800
@@ -297,10 +297,10 @@ static int hdmi_update_eld(struct hdmi_e
 					buf + ELD_FIXED_BYTES + mnl + 3 * i);
 	}
 
+	e->eld_valid = true;
 	return 0;
 
 out_fail:
-	e->eld_ver = 0;
 	return -EINVAL;
 }
 
@@ -323,9 +323,6 @@ int snd_hdmi_get_eld(struct hdmi_eld *el
 	 * ELD is valid, actual eld_size is assigned in hdmi_update_eld()
 	 */
 
-	if (!eld->eld_valid)
-		return -ENOENT;
-
 	size = snd_hdmi_get_eld_size(codec, nid);
 	if (size == 0) {
 		/* wfg: workaround for ASUS P5E-VM HDMI board */
--- linux.orig/sound/pci/hda/patch_hdmi.c	2011-11-15 21:02:25.000000000 +0800
+++ linux/sound/pci/hda/patch_hdmi.c	2011-11-15 21:13:42.000000000 +0800
@@ -980,20 +980,19 @@ static void hdmi_present_sense(struct hd
 	 * the unsolicited response to avoid custom WARs.
 	 */
 	int present = snd_hda_pin_sense(codec, pin_nid);
+	bool eld_valid = false;
 
-	memset(eld, 0, sizeof(*eld));
+	eld->eld_valid = false;
 
 	eld->monitor_present	= !!(present & AC_PINSENSE_PRESENCE);
 	if (eld->monitor_present)
-		eld->eld_valid	= !!(present & AC_PINSENSE_ELDV);
-	else
-		eld->eld_valid	= 0;
+		eld_valid	= !!(present & AC_PINSENSE_ELDV);
 
 	printk(KERN_INFO
 		"HDMI status: Codec=%d Pin=%d Presence_Detect=%d ELD_Valid=%d\n",
-		codec->addr, pin_nid, eld->monitor_present, eld->eld_valid);
+		codec->addr, pin_nid, eld->monitor_present, eld_valid);
 
-	if (eld->eld_valid)
+	if (eld_valid)
 		if (!snd_hdmi_get_eld(eld, codec, pin_nid))
 			snd_hdmi_show_eld(eld);