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ptrace - process trace system call for controlling and observing another process


The ptrace() system call is a means by which one process, termed the "tracer", can observe and control the execution of another process, known as the "tracee".

Through ptrace(), a tracer can examine and alter the tracee's memory and registers, essentially gaining a mechanism to inspect and manipulate the internal state of the tracee. The primary use case for ptrace() is in the implementation of debugging tools and other code-analysis utilities, which serve as aids in software development.

Additionally, ptrace() can be employed in malicious activities such as process injection, where it is used to attach to and modify a running process by writing arbitrary code into i.


  • request:int[K] - The specific operation to be performed, determined by constant values defined in the system headers.
  • pid:pid_t[K] - Process ID of the tracee.
  • addr:void *[K] - Address in the tracee's memory or a request-dependent value.
  • data:void *[K] - Data to be written to the tracee's memory or a request-dependent value.

Available Tags

  • K - Originated from kernel-space.
  • U - Originated from user space.
  • TOCTOU - Vulnerable to TOCTOU (time of check, time of use).
  • OPT - Optional argument - might not always be available (passed with null value).




Tracepoint (through sys_enter).


To observe and trace when the ptrace() system call is invoked and to gather contextual information about the operation being performed, the target process, and the data being accessed or modified.

Example Use Case

Developing a security monitoring system that tracks the usage of ptrace() to identify potentially malicious activities like process injection or unauthorized debugging attempts.


ptrace() can be used maliciously for process injection attacks, where an attacker attaches to a running process to modify its behavior, potentially leading to privilege escalation or other security breaches.

  • execve() - Execution of new program in a process.
  • fork() - Creation of a new process.
  • vfork() - Creation of a new process, sharing memory with parent.

This document was automatically generated by OpenAI and reviewed by a Human.