linux-user: Add support for prctl PR_GET_NAME and PR_SET_NAME

Add support for the prctl options PR_GET_NAME and PR_SET_NAME,
which take or return a name in a 16 byte buffer pointed to by arg2.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

linux-user/syscall.c

@@ -7253,6 +7253,30 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             }
             break;
         }
+#ifdef PR_GET_NAME
+        case PR_GET_NAME:
+        {
+            void *name = lock_user(VERIFY_WRITE, arg2, 16, 1);
+            if (!name) {
+                goto efault;
+            }
+            ret = get_errno(prctl(arg1, (unsigned long)name,
+                                  arg3, arg4, arg5));
+            unlock_user(name, arg2, 16);
+            break;
+        }
+        case PR_SET_NAME:
+        {
+            void *name = lock_user(VERIFY_READ, arg2, 16, 1);
+            if (!name) {
+                goto efault;
+            }
+            ret = get_errno(prctl(arg1, (unsigned long)name,
+                                  arg3, arg4, arg5));
+            unlock_user(name, arg2, 0);
+            break;
+        }
+#endif
         default:
             /* Most prctl options have no pointer arguments */
             ret = get_errno(prctl(arg1, arg2, arg3, arg4, arg5));