commit 9169294539ad46e08e2fe76a93c37ed965c13058
author Phil Burk <philburk@google.com> Fri Jun 30 12:23:05 2017 -0700
committer Phil Burk <philburk@google.com> Sat Jul 01 08:01:51 2017 -0700
tree 7f99790dd7625f12d19a1365666e4c541451f0ae
parent 6ec18f8ce3d797fdd5722926ac17c1f4eda7904d

aaudio: limit number of streams per process

Testing the new max streams restriction revealed the bug
involving the second shared stream.

Bug: 62951298
Bug: 63171495
Test: test_n_streams.cpp can open MAX_STREAMS_PER_PROCESS MMAP streams
Change-Id: Ibea7d9c4716326a37c669954b52f397ed2968caa

services/oboeservice/AAudioService.cpp

diff --git a/services/oboeservice/AAudioService.cpp b/services/oboeservice/AAudioService.cpp
index 585341a..91f7885 100644
--- a/services/oboeservice/AAudioService.cpp
+++ b/services/oboeservice/AAudioService.cpp
@@ -40,6 +40,8 @@
 using namespace android;
 using namespace aaudio;
 
+#define MAX_STREAMS_PER_PROCESS   8
+
 typedef enum
 {
     AAUDIO_HANDLE_TYPE_STREAM
@@ -86,6 +88,17 @@
     bool sharingModeMatchRequired = request.isSharingModeMatchRequired();
     aaudio_sharing_mode_t sharingMode = configurationInput.getSharingMode();
 
+    // Enforce limit on client processes.
+    pid_t pid = request.getProcessId();
+    if (pid != mCachedProcessId) {
+        int32_t count = AAudioClientTracker::getInstance().getStreamCount(pid);
+        if (count >= MAX_STREAMS_PER_PROCESS) {
+            ALOGE("AAudioService::openStream(): exceeded max streams per process %d >= %d",
+                  count,  MAX_STREAMS_PER_PROCESS);
+            return AAUDIO_ERROR_UNAVAILABLE;
+        }
+    }
+
     if (sharingMode != AAUDIO_SHARING_MODE_EXCLUSIVE && sharingMode != AAUDIO_SHARING_MODE_SHARED) {
         ALOGE("AAudioService::openStream(): unrecognized sharing mode = %d", sharingMode);
         return AAUDIO_ERROR_ILLEGAL_ARGUMENT;
@@ -135,7 +148,14 @@
 }
 
 aaudio_result_t AAudioService::closeStream(aaudio_handle_t streamHandle) {
-    AAudioServiceStreamBase *serviceStream = (AAudioServiceStreamBase *)
+    // Check permission first.
+    AAudioServiceStreamBase *serviceStream = convertHandleToServiceStream(streamHandle);
+    if (serviceStream == nullptr) {
+        ALOGE("AAudioService::startStream(), illegal stream handle = 0x%0x", streamHandle);
+        return AAUDIO_ERROR_INVALID_HANDLE;
+    }
+
+    serviceStream = (AAudioServiceStreamBase *)
             mHandleTracker.remove(AAUDIO_HANDLE_TYPE_STREAM,
                                   streamHandle);
     ALOGD("AAudioService.closeStream(0x%08X)", streamHandle);