diff --git a/library/entropy.c b/library/entropy.c
index 540a27c..caff22f 100644
--- a/library/entropy.c
+++ b/library/entropy.c
@@ -210,7 +210,7 @@
         if( ( ret = ctx->source[i].f_source( ctx->source[i].p_source,
                         buf, ENTROPY_MAX_GATHER, &olen ) ) != 0 )
         {
-            return( ret );
+            goto cleanup;
         }
 
         /*
@@ -223,7 +223,10 @@
         }
     }
 
-    return( 0 );
+cleanup:
+    polarssl_zeroize( buf, sizeof( buf ) );
+
+    return( ret );
 }
 
 /*
@@ -324,6 +327,8 @@
     ret = 0;
 
 exit:
+    polarssl_zeroize( buf, sizeof( buf ) );
+
 #if defined(POLARSSL_THREADING_C)
     if( polarssl_mutex_unlock( &ctx->mutex ) != 0 )
         return( POLARSSL_ERR_THREADING_MUTEX_ERROR );
@@ -354,12 +359,15 @@
     ret = 0;
 
 exit:
+    polarssl_zeroize( buf, sizeof( buf ) );
+
     fclose( f );
     return( ret );
 }
 
 int entropy_update_seed_file( entropy_context *ctx, const char *path )
 {
+    int ret = 0;
     FILE *f;
     size_t n;
     unsigned char buf[ ENTROPY_MAX_SEED_SIZE ];
@@ -375,14 +383,16 @@
         n = ENTROPY_MAX_SEED_SIZE;
 
     if( fread( buf, 1, n, f ) != n )
-    {
-        fclose( f );
-        return( POLARSSL_ERR_ENTROPY_FILE_IO_ERROR );
-    }
+        ret = POLARSSL_ERR_ENTROPY_FILE_IO_ERROR;
+    else
+        ret = entropy_update_manual( ctx, buf, n );
 
     fclose( f );
 
-    entropy_update_manual( ctx, buf, n );
+    polarssl_zeroize( buf, sizeof( buf ) );
+
+    if( ret != 0 )
+        return( ret );
 
     return( entropy_write_seed_file( ctx, path ) );
 }