[Android] Fix Microdump generation when Seccomp-BPF is enabled.

content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc

Index: content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc
diff --git a/content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc b/content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc
index c3b1605fc7dc6f091ae5456aad0371bcf2ee7c1a..0c760606f51a66e89d8f438efa9eb8c987957a3a 100644
--- a/content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc
+++ b/content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc
@@ -30,8 +30,10 @@ ResultExpr SandboxBPFBasePolicyAndroid::EvaluateSyscall(int sysno) const {
     case __NR_flock:
 #if defined(__x86_64__) || defined(__aarch64__)
     case __NR_newfstatat:
+    case __NR_getdents64:
 #elif defined(__i386__) || defined(__arm__) || defined(__mips__)
     case __NR_fstatat64:
+    case __NR_getdents:
 #endif
     case __NR_getpriority:
     case __NR_ioctl:
@@ -56,6 +58,15 @@ ResultExpr SandboxBPFBasePolicyAndroid::EvaluateSyscall(int sysno) const {
     case __NR_getrlimit:
 #endif
     case __NR_uname:
+
+    // Permit socket operations so that renderers can connect to logd and
+    // debuggerd.
+    case __NR_socket:

[mdempsky, 2016/02/05 18:31:46]

These seem scary.  Is there anything in place to prevent renderers from making
other arbitrary socket/connect calls?  Can we at least restrict socket() to only
create domain==AF_LOCAL/AF_UNIX sockets?

[Robert Sesek, 2016/02/05 19:57:12]

Yeah, I wasn't wild about having to add these, but it's necessary on Android. I
restricted it to PF_LOCAL/PF_UNIX and SOCK_DGRAM/SOCK_STREAM for now. SELinux
also provides some defense-in-depth here against opening network sockets from
isolated_app.

+    case __NR_connect:
+
+    // Ptrace is allowed so the Breakpad Microdumper can fork in a renderer
+    // and then ptrace the parent.
+    case __NR_ptrace:
       override_and_allow = true;
       break;
   }