nuttx/sched/environ/env_dup.c
Ville Juven 3581668c6b env_dup: Allocate memory from the correct memory pool
When the initial proxy task is duplicated into the first user task,
the environment exists in kernel memory and this must be copied to user
memory.

The memory allocated for the new task was allocated with the parent's
priority which is incorrect. Use the new task's priority instead.

Follow-up for: #5753
2022-03-22 10:15:29 +08:00

126 lines
3.8 KiB
C

/****************************************************************************
* sched/environ/env_dup.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifndef CONFIG_DISABLE_ENVIRON
#include <sys/types.h>
#include <sched.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/kmalloc.h>
#include "sched/sched.h"
#include "environ/environ.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: env_dup
*
* Description:
* Copy the internal environment structure of a task. This is the action
* that is performed when a new task is created: The new task has a
* private, exact duplicate of the parent task's environment.
*
* Input Parameters:
* group - The child task group to receive the newly allocated copy of the
* parent task groups environment structure.
*
* Returned Value:
* zero on success
*
* Assumptions:
* Not called from an interrupt handler.
*
****************************************************************************/
int env_dup(FAR struct task_group_s *group)
{
FAR struct tcb_s *ptcb = this_task();
FAR char *envp = NULL;
size_t envlen;
int ret = OK;
DEBUGASSERT(group != NULL && ptcb != NULL && ptcb->group != NULL);
/* Pre-emption must be disabled throughout the following because the
* environment may be shared.
*/
sched_lock();
/* Does the parent task have an environment? */
if (ptcb->group != NULL && ptcb->group->tg_envp != NULL)
{
/* Yes.. The parent task has an environment allocation. */
envlen = ptcb->group->tg_envsize;
envp = NULL;
/* A special case is that the parent has an "empty" environment
* allocation, i.e., there is an allocation in place but it
* contains no variable definitions and, hence, envlen == 0.
*/
if (envlen > 0)
{
/* There is an environment, duplicate it */
envp = (FAR char *)group_malloc(group, envlen);
if (envp == NULL)
{
/* The parent's environment can not be inherited due to a
* failure in the allocation of the child environment.
*/
envlen = 0;
ret = -ENOMEM;
}
else
{
/* Duplicate the parent environment. */
memcpy(envp, ptcb->group->tg_envp, envlen);
}
}
/* Save the size and child environment allocation. */
group->tg_envsize = envlen;
group->tg_envp = envp;
}
sched_unlock();
return ret;
}
#endif /* CONFIG_DISABLE_ENVIRON */