Home/ Questions/Q 8669689
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-12T18:32:14+00:00

Where does the filtering of environment variables occur? for instance, say you are using

  • 0

Where does the filtering of environment variables occur? for instance, say you are using LD_PRELOAD for shared library interposition. However, when a setuid program is run, the LD_PRELOAD variable has no effect. It represents a case of what I am dubbing "environment variable filtering." I was wondering where the processing and ‘purging’ of environment variables takes place, specifically and/or precisely.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    The dynamic loader deals with LD_PRELOAD and related environment variables. It also determines whether a program is running SUID and ignores the environment variables.

    The actual name and location of the dynamic loader varies by system. For example, on RHEL 5 for x86/64, the library is /lib/ld-linux.so.2 for 32-bit software and /lib64/ld-linux-x86-64.so.2 for 64-bit software; on Solaris 10 for SPARC, there’s /lib/ld.so.1 for 32-bit code, and /lib/sparcv9/ld.so.1 for 64-bit code.

    • 0