[PATCH] Add PR_GET_NAME

A while back we added the PR_SET_NAME prctl, but no PR_GET_NAME.  I guess
we should add this, if only to enable testing of PR_SET_NAME.
Signed-off-by: Prasanna Meda <pmeda@akamai.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/prctl.h

@@ -50,5 +50,6 @@
                                                    process timing */
 
 #define PR_SET_NAME    15		/* Set process name */
+#define PR_GET_NAME    16		/* Get process name */
 
 #endif /* _LINUX_PRCTL_H */

kernel/sys.c

@@ -1689,6 +1689,15 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
 			set_task_comm(me, ncomm);
 			return 0;
 		}
+		case PR_GET_NAME: {
+			struct task_struct *me = current;
+			unsigned char tcomm[sizeof(me->comm)];
+
+			get_task_comm(tcomm, me);
+			if (copy_to_user((char __user *)arg2, tcomm, sizeof(tcomm)))
+				return -EFAULT;
+			return 0;
+		}
 		default:
 			error = -EINVAL;
 			break;