add arch check

documentation/modules/exploit/linux/local/bpf_sign_extension_priv_esc.md

@@ -20,7 +20,7 @@ is thrown by the executable.
 
   1. Start msfconsole
   2. Exploit a box via whatever method
-  3. Do: `use exploit/linux/local/bpf_extension_priv_esc`
+  3. Do: `use exploit/linux/local/bpf_sign_extension_priv_esc`
   4. Do: `set session #`
   5. Do: `set verbose true`
   6. Do: `exploit`

modules/exploits/linux/local/bpf_sign_extension_priv_esc.rb

@@ -86,6 +86,13 @@ class MetasploitModule < Msf::Exploit::Local
     end
     vprint_good "Kernel version #{version} appears to be vulnerable"
 
+    arch = kernel_hardware
+    unless arch.include? 'x86_64'
+      vprint_error "System architecture #{arch} is not supported"
+      return CheckCode::Safe
+    end
+    vprint_good "System architecture #{arch} is supported"
+
     if session.type.to_s.eql? 'meterpreter'
       vprint_error 'Exploit can only be run on command shell sessions (Meterpreter does not work)'
     end