From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Hui Peng <phui@google.com>
Date: Tue, 16 May 2023 21:24:07 +0000
Subject: [PATCH] Fix an integer overflow bug in avdt_msg_asmbl

This is a backport of
Iaa4d603921fc4ffb8cfb5783f99ec0963affd6a2
to rvc-dev

Bug: 280633699
Test: manual
Ignore-AOSP-First: security
Tag: #security
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:26347d4bdba646bbba4d27337d2888a04de42639)
Merged-In: Iaa4d603921fc4ffb8cfb5783f99ec0963affd6a2
Change-Id: Iaa4d603921fc4ffb8cfb5783f99ec0963affd6a2
---
 stack/avdt/avdt_msg.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/stack/avdt/avdt_msg.cc b/stack/avdt/avdt_msg.cc
index af8d7014e..a98d59d4b 100644
--- a/stack/avdt/avdt_msg.cc
+++ b/stack/avdt/avdt_msg.cc
@@ -1293,14 +1293,14 @@ BT_HDR* avdt_msg_asmbl(tAVDT_CCB* p_ccb, BT_HDR* p_buf) {
        * NOTE: The buffer is allocated above at the beginning of the
        * reassembly, and is always of size BT_DEFAULT_BUFFER_SIZE.
        */
-      uint16_t buf_len = BT_DEFAULT_BUFFER_SIZE - sizeof(BT_HDR);
+      size_t buf_len = BT_DEFAULT_BUFFER_SIZE - sizeof(BT_HDR);
 
       /* adjust offset and len of fragment for header byte */
       p_buf->offset += AVDT_LEN_TYPE_CONT;
       p_buf->len -= AVDT_LEN_TYPE_CONT;
 
       /* verify length */
-      if ((p_ccb->p_rx_msg->offset + p_buf->len) > buf_len) {
+      if (((size_t) p_ccb->p_rx_msg->offset + (size_t) p_buf->len) > buf_len) {
         /* won't fit; free everything */
         AVDT_TRACE_WARNING("%s: Fragmented message too big!", __func__);
         osi_free_and_reset((void**)&p_ccb->p_rx_msg);
