When xApp subscribes to RC SM Style 1 (Message Copy), the gNB's signal_rrc_msg() path on rrcRelease handed an async indication to the E2 agent thread, then the calling code proceeded to UE-context teardown while the encoder was still walking the indication structure. Three issues observed in production: 1. malloc_or_fail() leaves union/pointer fields in rc_ind_data and its sub-structures uninitialized; the encoder dereferences whatever garbage was in the unused union member and corrupts the heap. Fix: switch malloc_or_fail(sizeof(...)) to calloc_or_fail(1, sizeof(...)) in fill_rrc_msg_copy, fill_ue_id, and the rc_ind_data_t allocations. 2. The async indication path runs concurrently with UE-context removal. Add rc_teardown_lock/rc_teardown_unlock helpers (public wrappers around rc_mutex) so the RRC layer can serialize teardown against any in-flight signal_rrc_msg() critical section. 3. Wrap rrc_gNB_remove_ue_context() in rrc_gNB.c with rc_teardown_lock/unlock under E2_AGENT. With these three fixes plus the deployment-side MALLOC_CHECK_=3 backstop, a 20-minute challenging-schedule run completes with 22 RRC_RELEASE events processed cleanly and zero crashes (vs. SIGSEGV within 10-30 minutes previously). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
OpenAirInterface License
The source code is distributed under CSSL v1.0. Some files, such as for orchestration, are distributed under MIT license(MIT.txt). Documentation is distributed under Creative Commons Attribution 4.0 International license.
All the files without an explicit copyright header have an implicit "Copyright of OpenAirInterface Authors".
Please see NOTICE for other licenses which are used in the software.
In the past OAI source code has been re-licensed sometimes, here is the history:
- CSSL v1.0 starting tag 2026.w14
- OAI Public License v1.1 starting tag v1.0 till
af4b0d53 - OAI Public License v1.0: starting tag v.04 till v1.0
- GPL 3: starting tag v.0 till v.04 (only initial implementation of 4G)
Where to Start
- General overview of documentation
- The implemented features
- System Requirements for Using OAI Stack
- How to build
- How to run the modems
Not all information is available in a central place, and information for specific sub-systems might be available in the corresponding sub-directories. To find all READMEs, this command might be handy:
find . -iname "readme*"
RAN repository structure
The OpenAirInterface (OAI) software is composed of the following parts:
openairinterface5g
├── charts
├── ci-scripts : Meta-scripts used by the OSA CI process. Contains also configuration files used day-to-day by CI.
├── CMakeLists.txt : Top-level CMakeLists.txt for building
├── cmake_targets : Build utilities to compile (simulation, emulation and real-time platforms), and generated build files.
├── common : Some common OAI utilities, some other tools can be found at openair2/UTILS.
├── doc : Documentation
├── docker : Dockerfiles to build for Ubuntu and RHEL
├── executables : Top-level executable source files (gNB, eNB, ...)
├── maketags : Script to generate emacs tags.
├── nfapi : (n)FAPI code for MAC-PHY interface
├── openair1 : Layer 1 (3GPP LTE Rel-10/12 PHY, NR Rel-15 PHY)
├── openair2 : Layer 2 (3GPP LTE Rel-10 MAC/RLC/PDCP/RRC/X2AP, LTE Rel-14 M2AP, NR Rel-15+ MAC/RLC/PDCP/SDAP/RRC/X2AP/F1AP/E1AP), E2AP
├── openair3 : Layer 3 (3GPP LTE Rel-10 S1AP/GTP, NR Rel-15 NGAP/GTP)
├── openshift : OpenShift helm charts for some deployment options of OAI
├── radio : Drivers for various radios such as USRP, AW2S, RFsim, 7.2 FHI, ...
├── targets : Some configuration files; only historical relevance, and might be deleted in the future
└── tools : Tools for use by the developers/ci machines: code analysis and formatting
How to get support from the OAI Community
You can ask your question on the mailing lists.
Your email should contain below information:
- A clear subject in your email.
- For all the queries there should be [Query] in the subject of the email and for problems there should be [Problem].
- In case of a problem, add a small description.
- Do not share any photos unless you want to share a diagram.
- OAI gNB/DU/CU/CU-CP/CU-UP configuration file in
.confformat only. - Logs of OAI gNB/DU/CU/CU-CP/CU-UP in
.logor.txtformat only. - In case your question is related to performance, include a small description of the machine (Operating System, Kernel version, CPU, RAM and networking card) and diagram of your testing environment.
- Known/open issues are present on GitLab, so keep checking.
Always remember a structured email will help us understand your issues quickly.
