commit ed4c4850064420264c83d74e955be0d621508cef
author Ranjith <quic_raluka@quicinc.com> Tue Dec 28 20:27:24 2021 +0530
committer Gerrit - the friendly Code Review server <code-review@localhost> Mon Jan 03 21:44:54 2022 -0800
tree 2d88a8f3cb9987f79d841ef76cd16493ec08487b
parent 889f093a2e4b8a394250b41bc186aa01e3696c41

plugins: tinyalsa: fix the subtraction overflow

Change-Id: I133a3261d94a031d2ebfe13041db687758b304e1

plugins/tinyalsa/src/agm_pcm_plugin.c

diff --git a/plugins/tinyalsa/src/agm_pcm_plugin.c b/plugins/tinyalsa/src/agm_pcm_plugin.c
index 3e07bf0..39fbfab 100644
--- a/plugins/tinyalsa/src/agm_pcm_plugin.c
+++ b/plugins/tinyalsa/src/agm_pcm_plugin.c
@@ -637,7 +637,7 @@
         else if ((snd_pcm_uframes_t)avail >= priv->pos_buf->boundary)
             avail -= priv->pos_buf->boundary;
     } else if (plugin->mode & PCM_IN) {
-        avail = priv->pos_buf->hw_ptr - priv->pos_buf->appl_ptr;
+        __builtin_sub_overflow(priv->pos_buf->hw_ptr, priv->pos_buf->appl_ptr, &avail);
         if (avail < 0)
             avail += priv->pos_buf->boundary;
     }