commit a5cee93b5add53afd25624f0f445f98bc8048b19
author Yifan Hong <elsk@google.com> Thu Feb 18 16:03:59 2021 -0800
committer Yifan Hong <elsk@google.com> Wed Mar 17 15:38:06 2021 -0700
tree 4f05c38f369f7ca8b1225d9c20c75e77ff324a4c
parent c4073d3e13ac7a769adbf95d5042407096e22f8a

fastbootd: add O_CLOEXEC/O_BINARY for OpenPartition

O_CLOEXEC ensures fastbootd does not leak fds to the parent
process (recovery).

O_BINARY has no effect in Linux, but it is explicit that
the file (partition) to read is a binary file.

Test: pass
Bug: 173654501

Change-Id: Idba922965ce666af1b7ee460ec7449fabd511c35

fastboot/device/utility.cpp

diff --git a/fastboot/device/utility.cpp b/fastboot/device/utility.cpp
index 4c84798..f9267e0 100644
--- a/fastboot/device/utility.cpp
+++ b/fastboot/device/utility.cpp
@@ -90,7 +90,8 @@
         return false;
     }
 
-    int flags = O_EXCL | (read ? O_RDONLY : O_WRONLY);
+    int flags = (read ? O_RDONLY : O_WRONLY);
+    flags |= (O_EXCL | O_CLOEXEC | O_BINARY);
     unique_fd fd(TEMP_FAILURE_RETRY(open(handle->path().c_str(), flags)));
     if (fd < 0) {
         PLOG(ERROR) << "Failed to open block device: " << handle->path();