hurd: Don't leak the auth port in msg* RPCs

The leak can be easily reproduced (and observed) using the portinfo
tool:

$ portinfo -v $$ | grep task
    36: send task(1577)(self) (refs: 127)
$ portinfo -v $$ | grep task
    36: send task(1577)(self) (refs: 253)
$ portinfo -v $$ | grep task
    36: send task(1577)(self) (refs: 379)
$ portinfo -v $$ | grep task
    36: send task(1577)(self) (refs: 505)
$ portinfo -v $$ | grep task
    36: send task(1577)(self) (refs: 631)

Checked on i686-gnu.

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429131354.2507443-5-bugaevc@gmail.com>
This commit is contained in:
Sergey Bugaev 2023-04-29 16:13:52 +03:00 committed by Samuel Thibault
parent 41aac87234
commit 0e12519fe0

View File

@ -35,11 +35,17 @@ kern_return_t
_S_msg_get_init_port (mach_port_t msgport, mach_port_t auth, int which,
mach_port_t *result, mach_msg_type_name_t *result_type)
{
error_t err;
AUTHCHECK;
*result_type = MACH_MSG_TYPE_MOVE_SEND;
/* This function adds a new user reference for the *RESULT it gives back.
Our reply message uses a move-send right that consumes this reference. */
return _hurd_ports_get (which, result);
err = _hurd_ports_get (which, result);
if (!err && MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return err;
}
kern_return_t
@ -51,10 +57,13 @@ _S_msg_set_init_port (mach_port_t msgport, mach_port_t auth,
AUTHCHECK;
err = _hurd_ports_set (which, port);
if (err == 0)
__mach_port_deallocate (__mach_task_self (), port);
return 0;
if (!err && MACH_PORT_VALID (port))
__mach_port_deallocate (__mach_task_self (), port);
if (!err && MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return err;
}
kern_return_t
@ -88,6 +97,8 @@ _S_msg_get_init_ports (mach_port_t msgport, mach_port_t auth,
}
*ports_type = MACH_MSG_TYPE_MOVE_SEND;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -108,6 +119,8 @@ _S_msg_set_init_ports (mach_port_t msgport, mach_port_t auth,
__mach_port_deallocate (__mach_task_self (), ports[i]);
}
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -152,9 +165,16 @@ kern_return_t
_S_msg_get_init_int (mach_port_t msgport, mach_port_t auth,
int which, int *value)
{
error_t err;
AUTHCHECK;
return get_int (which, value);
err = get_int (which, value);
if (err)
return err;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
kern_return_t
@ -185,6 +205,8 @@ _S_msg_get_init_ints (mach_port_t msgport, mach_port_t auth,
return err;
}
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -236,9 +258,16 @@ kern_return_t
_S_msg_set_init_int (mach_port_t msgport, mach_port_t auth,
int which, int value)
{
error_t err;
AUTHCHECK;
return set_int (which, value);
err = set_int (which, value);
if (err)
return err;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
kern_return_t
@ -261,6 +290,8 @@ _S_msg_set_init_ints (mach_port_t msgport, mach_port_t auth,
return err;
}
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -278,6 +309,8 @@ _S_msg_get_fd (mach_port_t msgport, mach_port_t auth, int which,
return errno;
*result_type = MACH_MSG_TYPE_MOVE_SEND;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -285,17 +318,25 @@ kern_return_t
_S_msg_set_fd (mach_port_t msgport, mach_port_t auth,
int which, mach_port_t port)
{
error_t err;
AUTHCHECK;
/* We consume the reference if successful. */
return HURD_FD_USE (which, (_hurd_port2fd (descriptor, port, 0), 0));
err = HURD_FD_USE (which, (_hurd_port2fd (descriptor, port, 0), 0));
if (err)
return err;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
/* Snarfing and frobbing environment variables. */
kern_return_t
_S_msg_get_env_variable (mach_port_t msgport,
const_string_t variable, //
const_string_t variable,
char **data, mach_msg_type_number_t *datalen)
{
error_t err;
@ -322,14 +363,17 @@ _S_msg_get_env_variable (mach_port_t msgport,
kern_return_t
_S_msg_set_env_variable (mach_port_t msgport, mach_port_t auth,
const_string_t variable, //
const_string_t value, //
const_string_t variable,
const_string_t value,
int replace)
{
AUTHCHECK;
if (__setenv (variable, value, replace)) /* XXX name space */
return errno;
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -381,6 +425,9 @@ _S_msg_set_environment (mach_port_t msgport, mach_port_t auth,
return errno;
__argz_extract (data, datalen, envp);
__environ = envp; /* XXX cooperate with loadenv et al */
if (MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return 0;
}
@ -433,6 +480,8 @@ _S_msg_get_dtable (mach_port_t process,
out:
__mutex_unlock (&_hurd_dtable_lock);
HURD_CRITICAL_END;
if (!err && MACH_PORT_VALID (auth))
__mach_port_deallocate (__mach_task_self (), auth);
return err;
}