--- a/security/sandbox/linux/SandboxFilter.cpp
+++ b/security/sandbox/linux/SandboxFilter.cpp
@@ -528,21 +528,16 @@ private:
   }
 
 public:
   explicit ContentSandboxPolicy(SandboxBrokerClient* aBroker,
                                 const std::vector<int>& aSyscallWhitelist)
     : mBroker(aBroker),
       mSyscallWhitelist(aSyscallWhitelist) {}
   ~ContentSandboxPolicy() override = default;
-  ResultExpr PrctlPolicy() const override {
-    // Ideally this should be restricted to a whitelist, but content
-    // uses enough things that it's not trivial to determine it.
-    return Allow();
-  }
   Maybe<ResultExpr> EvaluateSocketCall(int aCall) const override {
     switch(aCall) {
     case SYS_RECVFROM:
     case SYS_SENDTO:
     case SYS_SENDMMSG: // libresolv via libasyncns; see bug 1355274
       return Some(Allow());
 
     case SYS_SOCKETPAIR: {
@@ -840,21 +835,16 @@ public:
     case __NR_wait4:
 #ifdef __NR_waitpid
     case __NR_waitpid:
 #endif
       // NSPR will start a thread to wait for child processes even if
       // fork() fails; see bug 227246 and bug 1299581.
       return Error(ECHILD);
 
-#ifdef __NR_arch_prctl
-    case __NR_arch_prctl:
-#endif
-      return Allow();
-
     case __NR_eventfd2:
     case __NR_inotify_init:
     case __NR_inotify_init1:
     case __NR_inotify_add_watch:
     case __NR_inotify_rm_watch:
       return Allow();
 
 #ifdef __NR_memfd_create