Camera: Avoid freeing outstanding input buffers

The producer end can disconnect at any time which
will trigger the freeing of the input buffer. If
any input buffers are outstanding and being processed
by the camera device freeing them can cause stability
issues.

Bug: 63682712
Test: Manual using application.
Change-Id: I25da97786d75e82b1b13dce34953de597bea9b2e
diff --git a/services/camera/libcameraservice/device3/Camera3Stream.cpp b/services/camera/libcameraservice/device3/Camera3Stream.cpp
index e77421a..9e6ac79 100644
--- a/services/camera/libcameraservice/device3/Camera3Stream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3Stream.cpp
@@ -479,6 +479,7 @@
     if (res == OK) {
         fireBufferListenersLocked(*buffer, /*acquired*/true, /*output*/true);
         if (buffer->buffer) {
+            Mutex::Autolock l(mOutstandingBuffersLock);
             mOutstandingBuffers.push_back(*buffer->buffer);
         }
     }
@@ -486,11 +487,13 @@
     return res;
 }
 
-bool Camera3Stream::isOutstandingBuffer(const camera3_stream_buffer &buffer) {
+bool Camera3Stream::isOutstandingBuffer(const camera3_stream_buffer &buffer) const{
     if (buffer.buffer == nullptr) {
         return false;
     }
 
+    Mutex::Autolock l(mOutstandingBuffersLock);
+
     for (auto b : mOutstandingBuffers) {
         if (b == *buffer.buffer) {
             return true;
@@ -504,6 +507,8 @@
         return;
     }
 
+    Mutex::Autolock l(mOutstandingBuffersLock);
+
     for (auto b = mOutstandingBuffers.begin(); b != mOutstandingBuffers.end(); b++) {
         if (*b == *buffer.buffer) {
             mOutstandingBuffers.erase(b);
@@ -575,6 +580,7 @@
     if (res == OK) {
         fireBufferListenersLocked(*buffer, /*acquired*/true, /*output*/false);
         if (buffer->buffer) {
+            Mutex::Autolock l(mOutstandingBuffersLock);
             mOutstandingBuffers.push_back(*buffer->buffer);
         }
     }