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How to get Radare2 to use symbol table information for library calls?

Objdump can figure out when the binary is calling GLIBC functions, like printf:

 $ objdump -d crackme03.64 -Mintel | grep printf
 5c8:   ff 25 12 0a 20 00       jmp    QWORD PTR [rip+0x200a12]    #200fe0 <__printf_chk@GLIBC_2.3.4>

However, looking at the same address, Radare is much less helpful:

[0x000005c8]> pd 2
/ (fcn) sub.__cxa_finalize_224_5c8 8
|   sub.__cxa_finalize_224_5c8 ();
|           ; CALL XREF from 0x000007bc (sym.main)
|           ; CALL XREF from 0x00000809 (sym.main)
|           0x000005c8      ff25120a2000   jmp qword [reloc.__cxa_finalize_224] ; [0x200fe0:8]=0 LEA reloc.__cxa_finalize_224 ; reloc.__cxa_finalize_224
\           0x000005ce      6690           nop

Is there a way to ask Radare to figure out what these functions correspond to?

Solution

  • It should work if you're using the newest version from git.

    Radare2’s development is pretty quick – the project evolves every day, therefore it’s recommended to use the current git version. Update your version and it should solve your problem:

    $ git clone https://github.com/radare/radare2.git
$ cd radare2
$ ./sys/install.sh