Merge "libbinder: detach ParcelFileDescriptor comm"

am: a6d2152f14

Change-Id: I1e0383f588ec369e613cd01b164ccd42240d3102

1 files changed, 24 insertions, 2 deletions

diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index b3ae09b405..07d5c4bb2c 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -2239,8 +2239,30 @@ int Parcel::readParcelFileDescriptor() const
     int32_t hasComm = readInt32();
     int fd = readFileDescriptor();
     if (hasComm != 0) {
-        // skip
-        readFileDescriptor();
+        // detach (owned by the binder driver)
+        int comm = readFileDescriptor();
+
+        // warning: this must be kept in sync with:
+        // frameworks/base/core/java/android/os/ParcelFileDescriptor.java
+        enum ParcelFileDescriptorStatus {
+            DETACHED = 2,
+        };
+
+#if BYTE_ORDER == BIG_ENDIAN
+        const int32_t message = ParcelFileDescriptorStatus::DETACHED;
+#endif
+#if BYTE_ORDER == LITTLE_ENDIAN
+        const int32_t message = __builtin_bswap32(ParcelFileDescriptorStatus::DETACHED);
+#endif
+
+        ssize_t written = TEMP_FAILURE_RETRY(
+            ::write(comm, &message, sizeof(message)));
+
+        if (written == -1 || written != sizeof(message)) {
+            ALOGW("Failed to detach ParcelFileDescriptor written: %zd err: %s",
+                written, strerror(errno));
+            return BAD_TYPE;
+        }
     }
     return fd;
 }