Linux sandbox: allow *kill on ASAN

sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <fcntl.h>
 #include <linux/net.h>
@@ skipping 47 matching lines @@
   return false;
 #endif
 }
 
 }  // namespace.
 
 namespace sandbox {
 
 ErrorCode RestrictCloneToThreadsAndEPERMFork(SandboxBPF* sandbox) {
   // Glibc's pthread.
+  // TODO(jln): fix this on ASAN.
   if (!RunningOnASAN()) {
     return sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL,
                          CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
                          CLONE_THREAD | CLONE_SYSVSEM | CLONE_SETTLS |
                          CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID,
                          ErrorCode(ErrorCode::ERR_ALLOWED),
            sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL,
                          CLONE_PARENT_SETTID | SIGCHLD,
                          ErrorCode(EPERM),
            // ARM
@@ skipping 127 matching lines @@
                        SYS_SHUTDOWN, ErrorCode(ErrorCode::ERR_ALLOWED),
          sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL,
                        SYS_SENDMSG, ErrorCode(ErrorCode::ERR_ALLOWED),
          sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL,
                        SYS_RECVMSG, ErrorCode(ErrorCode::ERR_ALLOWED),
          ErrorCode(EPERM)))))))));
 }
 #endif
 
 ErrorCode RestrictKillTarget(pid_t target_pid, SandboxBPF* sandbox, int sysno) {
-  switch (sysno) {
-    case __NR_kill:
-    case __NR_tgkill:
-      return sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL,
-                           target_pid,
-                           ErrorCode(ErrorCode::ERR_ALLOWED),
-                           sandbox->Trap(SIGSYSKillFailure, NULL));
-    case __NR_tkill:
-      return sandbox->Trap(SIGSYSKillFailure, NULL);
-    default:
-      NOTREACHED();
-      return sandbox->Trap(CrashSIGSYS_Handler, NULL);
+  if (!RunningOnASAN()) {
+    switch (sysno) {
+      case __NR_kill:
+      case __NR_tgkill:
+        return sandbox->Cond(0,
+                             ErrorCode::TP_32BIT,
+                             ErrorCode::OP_EQUAL,
+                             target_pid,
+                             ErrorCode(ErrorCode::ERR_ALLOWED),
+                             sandbox->Trap(SIGSYSKillFailure, NULL));
+      case __NR_tkill:
+        return sandbox->Trap(SIGSYSKillFailure, NULL);
+      default:
+        NOTREACHED();
+        return sandbox->Trap(CrashSIGSYS_Handler, NULL);
+    }
+  } else {
+    switch (sysno) {
+      case __NR_kill:
+      case __NR_tgkill:
+      case __NR_tkill:
+        // On ASAN, fork() is not properly denied. This could lead to the
+        // strange

[mdempsky, 2014/04/30 00:21:14]

This comment is wrapped oddly though.

[Jorge Lucangeli Obes, 2014/04/30 00:22:05]

Indeed.

[jln (very slow on Chromium), 2014/04/30 00:27:49]

Done.

[jln (very slow on Chromium), 2014/04/30 00:27:49]

Done.

+        // failures we're observing with this policy on ASAN. TODO(jln): fix
+        // this.
+        return ErrorCode(ErrorCode::ERR_ALLOWED);
+      default:
+        NOTREACHED();
+        return sandbox->Trap(CrashSIGSYS_Handler, NULL);
+    }
   }
 }
 
 }  // namespace sandbox.