Revert "Enable Seccomp-BPF sandbox for renderers/workers and PPAPI processes on i386."

content/common/sandbox_seccomp_bpf_linux.cc

Index: content/common/sandbox_seccomp_bpf_linux.cc
diff --git a/content/common/sandbox_seccomp_bpf_linux.cc b/content/common/sandbox_seccomp_bpf_linux.cc
index a2bfecf3b351ab73fae2498202e8f47c1c505092..9ee2820499d6e601534c2d567e1700ff68deb2a6 100644
--- a/content/common/sandbox_seccomp_bpf_linux.cc
+++ b/content/common/sandbox_seccomp_bpf_linux.cc
@@ -48,14 +48,6 @@ inline bool IsChromeOS() {
 #endif
 }
 
-inline bool IsArchitectureI386() {
-#if defined(__i386__)
-  return true;
-#else
-  return false;
-#endif
-}
-
 inline bool IsArchitectureArm() {
 #if defined(__arm__)
   return true;
@@ -1201,18 +1193,11 @@ bool IsBaselinePolicyWatched(int sysno) {
   }
 }
 
+// x86_64 and ARM for now. Needs to be adapted and tested for i386.
 ErrorCode BaselinePolicy(int sysno) {
   if (IsBaselinePolicyAllowed(sysno)) {
     return ErrorCode(ErrorCode::ERR_ALLOWED);
   }
-
-#if defined(__i386__)
-  // socketcall(2) should be tightened.
-  if (IsSocketCall(sysno)) {
-    return ErrorCode(ErrorCode::ERR_ALLOWED);
-  }
-#endif
-
   // TODO(jln): some system calls in those sets are not supposed to
   // return ENOENT. Return the appropriate error.
   if (IsFileSystem(sysno) || IsCurrentDirectory(sysno)) {
@@ -1287,21 +1272,17 @@ ErrorCode RendererOrWorkerProcessPolicy(int sysno, void *) {
     case __NR_prlimit64:
       return ErrorCode(EPERM);  // See crbug.com/160157.
     default:
-      // These need further tightening.
 #if defined(__x86_64__) || defined(__arm__)
       if (IsSystemVSharedMemory(sysno))
         return ErrorCode(ErrorCode::ERR_ALLOWED);
 #endif
-#if defined(__i386__)
-      if (IsSystemVIpc(sysno))
-        return ErrorCode(ErrorCode::ERR_ALLOWED);
-#endif
 
       // Default on the baseline policy.
       return BaselinePolicy(sysno);
   }
 }
 
+// x86_64 and ARM for now. Needs to be adapted and tested for i386.
 ErrorCode FlashProcessPolicy(int sysno, void *) {
   switch (sysno) {
     case __NR_sched_getaffinity:
@@ -1311,15 +1292,12 @@ ErrorCode FlashProcessPolicy(int sysno, void *) {
     case __NR_ioctl:
       return ErrorCode(ENOTTY);  // Flash Access.
     default:
-      // These need further tightening.
 #if defined(__x86_64__) || defined(__arm__)
+      // These are under investigation, and hopefully not here for the long
+      // term.
       if (IsSystemVSharedMemory(sysno))
         return ErrorCode(ErrorCode::ERR_ALLOWED);
 #endif
-#if defined(__i386__)
-      if (IsSystemVIpc(sysno))
-        return ErrorCode(ErrorCode::ERR_ALLOWED);
-#endif
 
       // Default on the baseline policy.
       return BaselinePolicy(sysno);
@@ -1370,11 +1348,11 @@ void WarmupPolicy(Sandbox::EvaluateSyscall policy) {
 Sandbox::EvaluateSyscall GetProcessSyscallPolicy(
     const CommandLine& command_line,
     const std::string& process_type) {
+#if defined(__x86_64__) || defined(__arm__)
   if (process_type == switches::kGpuProcess) {
     // On Chrome OS, --enable-gpu-sandbox enables the more restrictive policy.
-    // However, we don't yet enable the more restrictive GPU process policy
-    // on i386 or ARM.
-    if (IsArchitectureI386() || IsArchitectureArm() ||
+    // However, we never enable the more restrictive GPU process policy on ARM.
+    if (IsArchitectureArm() ||
         (IsChromeOS() && !command_line.HasSwitch(switches::kEnableGpuSandbox)))
       return BlacklistDebugAndNumaPolicy;
     else
@@ -1399,6 +1377,12 @@ Sandbox::EvaluateSyscall GetProcessSyscallPolicy(
   NOTREACHED();
   // This will be our default if we need one.
   return AllowAllPolicy;
+#else
+  // On other architectures (currently IA32),
+  // we only have a small blacklist at the moment.
+  (void) process_type;
+  return BlacklistDebugAndNumaPolicy;
+#endif  // __x86_64__ || __arm__
 }
 
 // Initialize the seccomp-bpf sandbox.