task/pthread_cancelpt: Fix task_delete from another task group

PR #11165 causes an unnecessary regression; task_delete no longer works,
if the deleted task is from another group.

The logic that prevents this comes from:

nxnotify_cancellation() ->
tls_get_info_pid() ->
nxsched_get_stackinfo()

Which checks for permissions, which does not make sense in this case since
it is the kernel asking for the stack information.

Fix this by partially reverting 11165 and implementing a direct path for
the kernel to query for any tasks TLS.

include/nuttx/tls.h

@@ -316,28 +316,9 @@ uintptr_t task_tls_get_value(int tlsindex);
 #elif defined(CONFIG_TLS_ALIGNED) && !defined(__KERNEL__)
 #  define tls_get_info() TLS_INFO(up_getsp())
 #else
-#  define tls_get_info() tls_get_info_pid(0)
+FAR struct tls_info_s *tls_get_info(void);
 #endif
 
-/****************************************************************************
- * Name: tls_get_info_pid
- *
- * Description:
- *   Return a reference to the tls_info_s structure.  This is used as part
- *   of the internal implementation of tls_get/set_elem() and ONLY for the
- *   where CONFIG_TLS_ALIGNED is *not* defined or __KERNEL__ is defined.
- *
- * Input Parameters:
- *   pid - Thread ID to query, set to 0 to query own
- *
- * Returned Value:
- *   A reference to the thread-specific tls_info_s structure is return on
- *   success.  NULL would be returned in the event of any failure.
- *
- ****************************************************************************/
-
-FAR struct tls_info_s *tls_get_info_pid(pid_t pid);
-
 /****************************************************************************
  * Name: tls_destruct
  *

libs/libc/tls/tls_getinfo.c

@@ -36,7 +36,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: tls_get_info_pid
+ * Name: tls_get_info
  *
  * Description:
  *   Return a reference to the tls_info_s structure.  This is used as part
@@ -44,7 +44,7 @@
  *   where CONFIG_TLS_ALIGNED is *not* defined or __KERNEL__ is defined.
  *
  * Input Parameters:
- *   pid - Thread ID to query, set to 0 to query own
+ *   None.
  *
  * Returned Value:
  *   A reference to the thread-specific tls_info_s structure is return on
@@ -52,13 +52,13 @@
  *
  ****************************************************************************/
 
-FAR struct tls_info_s *tls_get_info_pid(pid_t pid)
+FAR struct tls_info_s *tls_get_info(void)
 {
   FAR struct tls_info_s *info = NULL;
   struct stackinfo_s stackinfo;
   int ret;
 
-  ret = nxsched_get_stackinfo(pid, &stackinfo);
+  ret = nxsched_get_stackinfo(0, &stackinfo);
   if (ret >= 0)
     {
       /* The TLS data lies at the lowest address of the stack allocation.

sched/sched/CMakeLists.txt

@@ -43,6 +43,7 @@ set(SRCS
     sched_idletask.c
     sched_self.c
     sched_get_stackinfo.c
+    sched_get_tls.c
     sched_sysinfo.c
     sched_reprioritizertr.c
     sched_get_stateinfo.c)

sched/sched/Make.defs

@@ -27,7 +27,7 @@ CSRCS += sched_setparam.c sched_setpriority.c sched_getparam.c
 CSRCS += sched_setscheduler.c sched_getscheduler.c
 CSRCS += sched_yield.c sched_rrgetinterval.c sched_foreach.c
 CSRCS += sched_lock.c sched_unlock.c sched_lockcount.c
-CSRCS += sched_idletask.c sched_self.c sched_get_stackinfo.c
+CSRCS += sched_idletask.c sched_self.c sched_get_stackinfo.c sched_get_tls.c
 CSRCS += sched_sysinfo.c sched_reprioritizertr.c sched_get_stateinfo.c
 
 ifeq ($(CONFIG_PRIORITY_INHERITANCE),y)

sched/sched/sched.h

@@ -417,4 +417,9 @@ void nxsched_suspend_critmon(FAR struct tcb_s *tcb);
 
 bool nxsched_verify_tcb(FAR struct tcb_s *tcb);
 
+/* Obtain TLS from kernel */
+
+struct tls_info_s; /* Forward declare */
+FAR struct tls_info_s *nxsched_get_tls(FAR struct tcb_s *tcb);
+
 #endif /* __SCHED_SCHED_SCHED_H */

sched/sched/sched_get_tls.c

@@ -0,0 +1,55 @@
+/****************************************************************************
+ * sched/sched/sched_get_tls.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>
+
+#include "nuttx/sched.h"
+#include "sched/sched.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxsched_get_tls
+ *
+ * Description:
+ *   Get TLS of any task / tcb with no security checks.
+ *
+ * Input Parameters:
+ *   tcb - The tcb to query.
+ *
+ * Returned Value:
+ *   Pointer to the TLS structure.
+ *
+ ****************************************************************************/
+
+FAR struct tls_info_s *nxsched_get_tls(FAR struct tcb_s *tcb)
+{
+  /* The TLS data lies at the lowest address of the stack allocation.
+   * This is true for both push-up and push-down stacks.
+   */
+
+  return (FAR struct tls_info_s *)tcb->stack_alloc_ptr;
+}

sched/task/task_cancelpt.c

@@ -88,7 +88,7 @@
 
 bool nxnotify_cancellation(FAR struct tcb_s *tcb)
 {
-  FAR struct tls_info_s *tls = tls_get_info_pid(tcb->pid);
+  FAR struct tls_info_s *tls = nxsched_get_tls(tcb);
   irqstate_t flags;
   bool ret = false;