#2548 amfa: process crashed when registering component without SA_AMF_COMPONENT_NAME

[Nguyen TK Luu]

The issue was found when testing the API saAmfComponentRegister(). Start a process that calls saAmfInitialize(), then calls saAmfComponentRegister() with a non-existing component name, with the environment variable SA_AMF_COMPONENT_NAME deliberately not set (not started by AMF), the process will get aborted (osaf_abort(1)).

That was caused by the following buggy condition check in the saAmfComponentRegister() function:

  ...
  /* retrieve AvA CB */
  if (!(cb = (AVA_CB *)ncshm_take_hdl(NCS_SERVICE_ID_AVA, gl_ava_hdl)) ||
      !m_AVA_FLAG_IS_COMP_NAME(cb)) {
    TRACE_4("SA_AIS_ERR_LIBRARY: Unable to retrieve cb handle");
    rc = SA_AIS_ERR_LIBRARY;
    goto done;
  }
  /* acquire cb read lock */
  m_NCS_LOCK(&cb->lock, NCS_LOCK_READ);
  ...

  done:
  /* release cb read lock and return handles */
  if (cb) {
    m_NCS_UNLOCK(&cb->lock, NCS_LOCK_READ);
    ncshm_give_hdl(gl_ava_hdl);
  }
  ...

  TRACE_LEAVE2("rc:%u", rc);
  return rc;

In this case, the !m_AVA_FLAG_IS_COMP_NAME(cb) check failed as SA_AMF_COMPONENT_NAME was not set, the execution jumped to 'done:' which tried to unlock a not-owned mutex (not previously locked yet), leading to osaf_abort() of the invoking process.

[Nguyen TK Luu]

commit 0983225ed4a27eb466648aed4f463b672e92efda (origin/develop)
Author: Nguyen Luu nguyen.tk.luu@dektech.com.au
Date: Thu Aug 10 20:03:54 2017 +0700

amfa: Fix API internal check to avoid fatal mutex unlock [#2548]

Current check for the required setting of the SA_AMF_COMPONENT_NAME
env variable in some AMF API's (ComponentRegister, QuiescingComplete)
would crash the invoking process if that env variable was missed
to be set for some reason, as the agent lib tries, during cleanup,
to unlock a mutex which it has not previously locked yet.