From: Richard Mudgett <rmudgett@digium.com>
Date: Wed, 15 Nov 2017 00:00:55 +0000 (-0600)
Subject: audiohook.c: Fix freeing a frame and still using it.
X-Git-Tag: 13.19.0-rc1~124^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7f916d621a5cceb7173fb5a86d540c73862ce5a2;p=thirdparty%2Fasterisk.git

audiohook.c: Fix freeing a frame and still using it.

Memory corruption happened to the media frame caches when an audio hook
freed a frame when it shouldn't.  I think the freed frame was because a
jitter buffer interpolated a missing frame and the audio hook
unconditionally freed it.

* Made audiohook.c:audio_audiohook_write_list() not free an interpolated
frame if it is the same frame as what was passed into the routine.

* Made plc.c:normalise_history() use memmove() instead of memcpy() on a
memory block that could overlap.  Found by valgrind investigating this
issue.

ASTERISK-27238
ASTERISK-27412

Change-Id: I548d86894281fc4529aefeb9f161f2131ecc6fde
---

diff --git a/main/audiohook.c b/main/audiohook.c
index 869cb750e8..cb3c4bcb31 100644
--- a/main/audiohook.c
+++ b/main/audiohook.c
@@ -947,7 +947,9 @@ static struct ast_frame *audio_audiohook_write_list(struct ast_channel *chan, st
 	 * rely on actual media being present to do things.
 	 */
 	if (!middle_frame->data.ptr) {
-		ast_frfree(middle_frame);
+		if (middle_frame != start_frame) {
+			ast_frfree(middle_frame);
+		}
 		return start_frame;
 	}
 
diff --git a/main/plc.c b/main/plc.c
index 1f0206920e..4421e7a0cf 100644
--- a/main/plc.c
+++ b/main/plc.c
@@ -98,7 +98,7 @@ static void normalise_history(plc_state_t *s)
 	if (s->buf_ptr == 0)
 		return;
 	memcpy(tmp, s->history, sizeof(int16_t)*s->buf_ptr);
-	memcpy(s->history, s->history + s->buf_ptr, sizeof(int16_t) * (PLC_HISTORY_LEN - s->buf_ptr));
+	memmove(s->history, s->history + s->buf_ptr, sizeof(int16_t) * (PLC_HISTORY_LEN - s->buf_ptr));
 	memcpy(s->history + PLC_HISTORY_LEN - s->buf_ptr, tmp, sizeof(int16_t) * s->buf_ptr);
 	s->buf_ptr = 0;
 }