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Use of a Non-reentrant Function in a Concurrent Context

Draft Base
Structure: Simple
Description

The product calls a non-reentrant function in a concurrent context in which a competing code sequence (e.g. thread or signal handler) may have an opportunity to call the same function or otherwise influence its state.

Common Consequences 1
Scope: IntegrityConfidentialityOther

Impact: Modify MemoryRead MemoryModify Application DataRead Application DataAlter Execution Logic
Potential Mitigations 3
Phase: Implementation
Use reentrant functions if available.
Phase: Implementation
Add synchronization to your non-reentrant function.
Phase: Implementation
In Java, use the ReentrantLock Class.
Demonstrative Examples 2

ID : DX-171

In this example, a signal handler uses syslog() to log a message:

Code Example:

Bad
C
c

ID : DX-172

The following code relies on getlogin() to determine whether or not a user is trusted. It is easily subverted.

Code Example:

Bad
C
c
Observed Examples 2
CVE-2001-1349unsafe calls to library functions from signal handler
CVE-2004-2259SIGCHLD signal to FTP server can cause crash under heavy load while executing non-reentrant functions like malloc/free.
References 2
Java Concurrency API
SUN
https://docs.oracle.com/javase/1.5.0/docs/api/java/util/concurrent/locks/ReentrantLock.html(2023-04-07)
ID: REF-547
Use reentrant functions for safer signal handling
Dipak Jha, Software Engineer, IBM
https://archive.ph/rl1XR(2023-04-07)
ID: REF-548
Modes of Introduction
Implementation
Related Attack Patterns
Related Weaknesses
ChildOf: Improper Synchronization (CWE-662)