Merge bitcoin#10837: Fix resource leak on error in GetDevURandom

a8ae0b2 Fix resource leak (Dag Robole)

Pull request description:

  Fixes a potential file handle leak when size of entropy is invalid

Tree-SHA512: 692d24daaf370bba1f842925b037275126f9494f54769650bcf5829c794a0fb8561a86f42347bdf088a484e4f107bce7fa14cd7bdbfb4ecfbeb51968953da3ae

src/random.cpp

@@ -186,6 +186,7 @@ void GetDevURandom(unsigned char *ent32)
     do {
         ssize_t n = read(f, ent32 + have, NUM_OS_RANDOM_BYTES - have);
         if (n <= 0 || n + have > NUM_OS_RANDOM_BYTES) {
+            close(f);
             RandFailure();
         }
         have += n;