webservd: add native 64-bit syscalls

The syscall filter is written mostly for arm and is missing a bunch
of syscalls used on native 64-bit arches like amd64.  Add them here.

BUG=None
TEST=webservd doesn't crash on amd64-generic anymore

Change-Id: I2ed016d7a76d42996b2669b37c12f1263d776a27
Reviewed-on: https://chromium-review.googlesource.com/424633
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Garret Kelly <gdk@chromium.org>

webservd/usr/share/filters/webservd-seccomp.policy

diff --git a/webservd/usr/share/filters/webservd-seccomp.policy b/webservd/usr/share/filters/webservd-seccomp.policy
index 9c4b55e..00a9ceb 100644
--- a/webservd/usr/share/filters/webservd-seccomp.policy
+++ b/webservd/usr/share/filters/webservd-seccomp.policy
@@ -22,19 +22,28 @@
 clock_gettime: 1
 close: 1
 connect: 1
+creat: 1
 dup: 1
 epoll_create: 1
 epoll_ctl: 1
 epoll_wait: 1
 exit_group: 1
+fcntl: 1
 fcntl64: 1
+fstat: 1
 fstat64: 1
 futex: 1
+getdents: 1
 getdents64: 1
+getegid: 1
 getegid32: 1
+geteuid: 1
 geteuid32: 1
+getgid: 1
 getgid32: 1
+getresgid: 1
 getresgid32: 1
+getresuid: 1
 getresuid32: 1
 # arm
 ugetrlimit: 1
@@ -42,8 +51,10 @@
 getsockname: 1
 gettid: 1
 gettimeofday: 1
+getuid: 1
 getuid32: 1
 listen: 1
+lstat: 1
 lstat64: 1
 mmap2: 1
 mprotect: 1
@@ -63,14 +74,18 @@
 rt_sigprocmask: 1
 # arm
 _newselect: 1
+select: 1
 send: 1
 sendmsg: 1
 set_robust_list: 1
 set_tid_address: 1
 # arm
 ARM_set_tls: 1
+setgroups: 1
 setgroups32: 1
+setresgid: 1
 setresgid32: 1
+setresuid: 1
 setresuid32: 1
 setsockopt: 1
 shutdown: 1
@@ -79,6 +94,7 @@
 socket: arg0 == 0x1 || arg0 == 0xa || arg0 == 0x2
 # socketpair: arg0 == PF_LOCAL
 socketpair: arg0 == 0x1
+stat: 1
 stat64: 1
 tgkill: 1
 uname: 1