FindMap

This python script adds a new commmand findmap, which parses the output of info proc mappings and finds the origin file plus offset which is mapped at the given address.

This script is known to work with GDB 14.2 + Python 3.12.3.

Usage

>>> source gdb-findmap.py

>>> findmap malloc(1)
Mapping:
          Start Addr           End Addr       Size     Offset  Perms  objfile
      0x5555555a7000     0x5555555c8000    0x21000        0x0  rw-p   [heap]
Origin: [heap] + 0x300

>>> findmap sin
Mapping:
          Start Addr           End Addr       Size     Offset  Perms  objfile
      0x7ffff7eac000     0x7ffff7f2c000    0x80000     0xe000  r-xp   /usr/lib/libm.so.6
Origin: /usr/lib/libm.so.6 + 0x2f250

>>> findmap $rsp
Mapping:
          Start Addr           End Addr       Size     Offset  Perms  objfile
      0x7ffffffdd000     0x7ffffffff000    0x22000        0x0  rw-p   [stack]
Origin: [stack] + 0x20998

>>> findmap 0x7ffff7e94123
Mapping:
          Start Addr           End Addr       Size     Offset  Perms  objfile
      0x7ffff7e94000     0x7ffff7e97000     0x3000    0x4d000  r--p   /usr/lib/libreadline.so.8.2
Origin: /usr/lib/libreadline.so.8.2 + 0x4d123

For example, output Origin: /usr/lib/libm.so.6 + 0x2f250 for findmap sin means that function sin is located in /usr/lib/libm.so.6, 0x2f250 bytes into the file.