hurd: Fix FS_RETRY_MAGICAL "machtype" handling

We need to set file_name, not update retryname. This is what the other
branches do.

Before this change, any attempt to access such a file would segfault due
to file_name being unset:

$ settrans -ac /tmp/my-machtype /hurd/magic machtype
$ cat /tmp/my-machtype
Segmentation fault

Checked on i686-gnu.

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429131354.2507443-7-bugaevc@gmail.com>

diff --git a/hurd/lookup-retry.c b/hurd/lookup-retry.c
index 99c981046f19944eed551d7fb85c66f52ee71531..62f94bbc92c40ba9337af83662be0527870de285 100644 (file)
--- a/hurd/lookup-retry.c
+++ b/hurd/lookup-retry.c
@@ -277,7 +277,6 @@ __hurd_file_name_lookup_retry (error_t (*use_init_port)
                  error_t err;
                  struct host_basic_info hostinfo;
                  mach_msg_type_number_t hostinfocnt = HOST_BASIC_INFO_COUNT;
-                 char *p;
                  /* XXX want client's host */
                  if (err = __host_info (__mach_host_self (), HOST_BASIC_INFO,
                                         (integer_t *) &hostinfo,
@@ -288,13 +287,11 @@ __hurd_file_name_lookup_retry (error_t (*use_init_port)
                      err = EGRATUITOUS;
                      goto out;
                    }
-                 p = _itoa (hostinfo.cpu_subtype, &retryname[8], 10, 0);
-                 *--p = '/';
-                 p = _itoa (hostinfo.cpu_type, &retryname[8], 10, 0);
-                 if (p < retryname)
+                 file_name = _itoa (hostinfo.cpu_subtype, &retryname[8], 10, 0);
+                 *--file_name = '/';
+                 file_name = _itoa (hostinfo.cpu_type, file_name, 10, 0);
+                 if (file_name < retryname)
                    abort ();   /* XXX write this right if this ever happens */
-                 if (p > retryname)
-                   memmove (retryname, p, strlen(p) + 1);
                  startdir = *result;
                }
              else