Allow the seccomp sandbox to be enabled, even if the suid sandbox has...

sandbox/linux/seccomp/mmap.cc

 #include "debug.h"
 #include "sandbox_impl.h"
 
 namespace playground {
 
 void* Sandbox::sandbox_mmap(void *start, size_t length, int prot, int flags,
                           int fd, off_t offset) {
   Debug::syscall(__NR_mmap, "Executing handler");
   struct {
     int       sysnum;
@@ skipping 12 matching lines @@
   void* rc;
   SysCalls sys;
   if (write(sys, processFdPub(), &request, sizeof(request)) !=
       sizeof(request) ||
       read(sys, threadFdPub(), &rc, sizeof(rc)) != sizeof(rc)) {
     die("Failed to forward mmap() request [sandbox]");
   }
   return rc;
 }
 
-bool Sandbox::process_mmap(int parentProc, int sandboxFd, int threadFdPub,
+bool Sandbox::process_mmap(int parentMapsFd, int sandboxFd, int threadFdPub,
                            int threadFd, SecureMem::Args* mem) {
   // Read request
   SysCalls sys;
   MMap mmap_req;
   if (read(sys, sandboxFd, &mmap_req, sizeof(mmap_req)) != sizeof(mmap_req)) {
     die("Failed to read parameters for mmap() [process]");
   }
 
   if (mmap_req.flags & MAP_FIXED) {
     // Cannot map a memory area that was part of the original memory mappings.
@@ skipping 16 matching lines @@
   }
 
   // All other mmap() requests are OK
   SecureMem::sendSystemCall(threadFdPub, false, -1, mem, __NR_MMAP,
                             mmap_req.start, mmap_req.length, mmap_req.prot,
                             mmap_req.flags, mmap_req.fd, mmap_req.offset);
   return true;
 }
 
 } // namespace