From: redi <redi@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri, 11 Sep 2015 13:44:26 +0000 (+0000)
Subject: Check read() result in std::random_device.
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=84bb4e67d45a8921cedd2ef64fe3cffd9ee72f44;p=thirdparty%2Fgcc.git

Check read() result in std::random_device.

	PR libstdc++/65142
	* src/c++11/random.cc (random_device::_M_getval()): Check read result.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@227687 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 42f6a54b94eb..b4618effe80d 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,8 @@
+2015-09-11  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/65142
+	* src/c++11/random.cc (random_device::_M_getval()): Check read result.
+
 2015-09-11  John Marino  <gnugcc@marino.st>
 	    Jonathan Wakely  <jwakely@redhat.com>
 
diff --git a/libstdc++-v3/src/c++11/random.cc b/libstdc++-v3/src/c++11/random.cc
index edf900f6bb73..1d102c755b2e 100644
--- a/libstdc++-v3/src/c++11/random.cc
+++ b/libstdc++-v3/src/c++11/random.cc
@@ -130,13 +130,17 @@ namespace std _GLIBCXX_VISIBILITY(default)
 #endif
 
     result_type __ret;
+
 #ifdef _GLIBCXX_HAVE_UNISTD_H
-    read(fileno(static_cast<FILE*>(_M_file)),
-	 static_cast<void*>(&__ret), sizeof(result_type));
+    auto e = read(fileno(static_cast<FILE*>(_M_file)),
+		  static_cast<void*>(&__ret), sizeof(result_type));
 #else
-    std::fread(static_cast<void*>(&__ret), sizeof(result_type),
-	       1, static_cast<FILE*>(_M_file));
+    auto e = std::fread(static_cast<void*>(&__ret), sizeof(result_type),
+		        1, static_cast<FILE*>(_M_file));
 #endif
+    if (e != sizeof(result_type))
+      __throw_runtime_error(__N("random_device could not read enough bytes"));
+
     return __ret;
   }