diff mbox series

[hurd,commited] hurd: Fix auth port leak

Message ID 20220104001517.3835827-1-samuel.thibault@ens-lyon.org
State New
Headers show
Series [hurd,commited] hurd: Fix auth port leak | expand

Commit Message

Samuel Thibault Jan. 4, 2022, 12:15 a.m. UTC 
If access() was used before exec, _hurd_id.rid_auth would cache an
"effective" auth port.  We do not want this to leak into the executed
program.
---
 hurd/hurdexec.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)
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Patch

diff --git a/hurd/hurdexec.c b/hurd/hurdexec.c
index 3dc61431d5..5b27f1861b 100644
--- a/hurd/hurdexec.c
+++ b/hurd/hurdexec.c
@@ -229,6 +229,14 @@  retry:
      reflects that our whole ID set differs from what we've set it to.  */
   __mutex_lock (&_hurd_id.lock);
   err = _hurd_check_ids ();
+
+  /* Avoid leaking the rid_auth port reference to the new progam */
+  if (_hurd_id.rid_auth != MACH_PORT_NULL)
+    {
+      __mach_port_deallocate (__mach_task_self (), _hurd_id.rid_auth);
+      _hurd_id.rid_auth = MACH_PORT_NULL;
+    }
+
   if (err == 0 && ((_hurd_id.aux.nuids >= 2 && _hurd_id.gen.nuids >= 1
 		    && _hurd_id.aux.uids[1] != _hurd_id.gen.uids[0])
 		   || (_hurd_id.aux.ngids >= 2 && _hurd_id.gen.ngids >= 1
@@ -244,11 +252,6 @@  retry:
       _hurd_id.aux.uids[1] = _hurd_id.gen.uids[0];
       _hurd_id.aux.gids[1] = _hurd_id.gen.gids[0];
       _hurd_id.valid = 0;
-      if (_hurd_id.rid_auth != MACH_PORT_NULL)
-	{
-	  __mach_port_deallocate (__mach_task_self (), _hurd_id.rid_auth);
-	  _hurd_id.rid_auth = MACH_PORT_NULL;
-	}
 
       err = __auth_makeauth (ports[INIT_PORT_AUTH],
 			     NULL, MACH_MSG_TYPE_COPY_SEND, 0,