[quandary] allocation as a sink

Reviewed By: the-st0rm

Differential Revision: D5029613

fbshipit-source-id: db0924e

infer/src/quandary/ClangTrace.ml

@@ -91,11 +91,13 @@ module CppSource = Source.Make(SourceKind)
 module SinkKind = struct
 
   type t =
+    | Allocation (** memory allocation *)
     | ShellExec (** shell exec function *)
     | Other (** for testing or uncategorized sinks *)
   [@@deriving compare]
 
   let of_string = function
+    | "Allocation" -> Allocation
     | "ShellExec" -> ShellExec
     | _ -> Other
 
@@ -141,6 +143,8 @@ module SinkKind = struct
           match Typ.Procname.to_string pname with
           | "execl" | "execlp" | "execle" | "execv" | "execvp" ->
               taint_all actuals ShellExec ~report_reachable:false
+          | "brk" | "calloc" | "malloc" | "realloc" | "sbrk" ->
+              taint_all actuals Allocation ~report_reachable:false
           | _ ->
               Option.value (get_external_sink pname actuals) ~default:[]
         end
@@ -151,9 +155,12 @@ module SinkKind = struct
     | pname ->
         failwithf "Non-C++ procname %a in C++ analysis@." Typ.Procname.pp pname
 
-  let pp fmt = function
-    | ShellExec -> F.fprintf fmt "ShellExec"
-    | Other -> F.fprintf fmt "Other"
+  let pp fmt kind =
+    F.fprintf fmt
+      (match kind with
+       | Allocation -> "Allocation"
+       | ShellExec -> "ShellExec"
+       | Other -> "Other")
 end
 
 module CppSink = Sink.Make(SinkKind)
@@ -165,11 +172,15 @@ include
 
     let should_report source sink =
       match Source.kind source, Sink.kind sink with
-      | EnvironmentVariable, ShellExec
-      | File, ShellExec ->
+      | (EnvironmentVariable | File), ShellExec ->
           (* untrusted data flowing to exec *)
           true
-      | Other, Other ->
+      | (EnvironmentVariable | File), Allocation ->
+          (* untrusted data flowing to memory allocation *)
+          true
+      | Other, _
+      | _, Other ->
+          (* Other matches everything *)
           true
       | _ ->
           false

infer/tests/codetoanalyze/cpp/quandary/.inferconfig

@@ -19,6 +19,10 @@
     {
       "procedure": "basics::Obj::string_source",
       "kind": "Other"
+    },
+    {
+      "procedure": "allocs::allocation_source",
+      "kind": "EnvironmentVariable"
     }
   ],
   "quandary-sinks": [

infer/tests/codetoanalyze/cpp/quandary/allocs.cpp

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2017 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+
+namespace allocs {
+
+extern int* allocation_source();
+
+void untrusted_malloc_bad() { malloc(*allocation_source()); }
+
+void untrusted_calloc_bad1() { calloc(*allocation_source(), sizeof(int)); }
+
+void untrusted_calloc_bad2() { calloc(5, *allocation_source()); }
+
+void untrusted_reaalloc_bad1() { realloc(allocation_source(), sizeof(int)); }
+
+void untrusted_reaalloc_bad2(int* i) { realloc(i, *allocation_source()); }
+
+void untrusted_brk_bad() { brk((void*)allocation_source()); }
+
+void untrusted_sbrk_bad() { sbrk(*allocation_source()); }
+}

infer/tests/codetoanalyze/cpp/quandary/issues.exp

@@ -1,3 +1,10 @@
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_brk_bad, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to brk]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_calloc_bad1, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to calloc]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_calloc_bad2, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to calloc]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_malloc_bad, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to malloc]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_reaalloc_bad1, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to realloc]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_reaalloc_bad2, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to realloc]
+codetoanalyze/cpp/quandary/allocs.cpp, allocs::untrusted_sbrk_bad, 1, QUANDARY_TAINT_ERROR, [return from allocs::allocation_source,call to sbrk]
 codetoanalyze/cpp/quandary/basics.cpp, basics::object_source_sink_bad, 2, QUANDARY_TAINT_ERROR, [return from basics::Obj_method_source,call to basics::Obj_method_sink]
 codetoanalyze/cpp/quandary/basics.cpp, basics::propagateBad, 3, QUANDARY_TAINT_ERROR, [return from __infer_taint_source,flow through basics::id,call to basics::callSink,call to __infer_taint_sink]
 codetoanalyze/cpp/quandary/basics.cpp, basics::returnSourceToSinkBad, 2, QUANDARY_TAINT_ERROR, [return from __infer_taint_source,return from basics::returnSource,call to __infer_taint_sink]