[PATCH 3.16 60/83] ALSA: hda - Fix potential endless loop at applying quirks

[Ben Hutchings]

3.16.78-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Takashi Iwai <tiwai@xxxxxxx>

commit 333f31436d3db19f4286f8862a00ea1d8d8420a1 upstream.

Since the chained quirks via chained_before flag is applied before the
depth check, it may lead to the endless recursive calls, when the
chain were set up incorrectly.  Fix it by moving the depth check at
the beginning of the loop.

Fixes: 1f57825077dc ("ALSA: hda - Add chained_before flag to the fixup entry")
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 sound/pci/hda/hda_auto_parser.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/sound/pci/hda/hda_auto_parser.c
+++ b/sound/pci/hda/hda_auto_parser.c
@@ -787,6 +787,8 @@ static void apply_fixup(struct hda_codec
 	while (id >= 0) {
 		const struct hda_fixup *fix = codec->fixup_list + id;
 
+		if (++depth > 10)
+			break;
 		if (fix->chained_before)
 			apply_fixup(codec, fix->chain_id, action, depth + 1);
 
@@ -826,8 +828,6 @@ static void apply_fixup(struct hda_codec
 		}
 		if (!fix->chained || fix->chained_before)
 			break;
-		if (++depth > 10)
-			break;
 		id = fix->chain_id;
 	}
 }