NSS and static binaries

[Neal H Walfield]

When using NSS functionality in a static binary, NSS still uses shared
libraries.  This is explained in the libc faq, section 2.22.

Unfortunentally, this does not work on the Hurd.  Here is a small test
case using initgroups:

initgroups.c:

        #define _GNU_SOURCE 
        #include <grp.h>
        #include <stdio.h>
        #include <errno.h>
        #include <error.h>

        int
        main (int argc, char *argv[])
        {
          int err;

          err = initgroups ("neal", -1);
          if (err == -1)
            error (1, errno, "initgroups");

          printf ("Success.\n");
          return 0;
        }

Here is the output on GNU/Linux with glibc 2.2.3-9:


        neal@bassanio:~/initgroups (0)$ make
        cc -Wall -g -static -o initgroups-static initgroups.c
        cc -Wall -g -o initgroups initgroups.c
        neal@bassanio:~/initgroups (0)$ ./initgroups
        ./initgroups: initgroups: Operation not permitted
        neal@bassanio:~/initgroups (1)$ ./initgroups-static
        ./initgroups-static: initgroups: Operation not permitted
        neal@bassanio:~/initgroups (1)$ 

and on the GNU/Hurd with glibc 2.2.3-9:

        neal@desdemona:~/initgroups (0)$ make
        cc -Wall -g -static -o initgroups-static initgroups.c
        cc -Wall -g -o initgroups initgroups.c
        neal@desdemona:~/initgroups (0)$ ./initgroups
        ./initgroups: initgroups: Operation not permitted
        neal@desdemona:~/initgroups (1)$ ./initgroups-static 
        Segmentation fault
        neal@desdemona:~/initgroups (139)$ gdb initgroups-static
        GNU gdb 5.0

        [ snip ]

        This GDB was configured as "i386-unknown-gnu0.2"...
        (gdb) run
        Starting program: /home/neal/initgroups/initgroups-static 
        
        Program received signal SIGSEGV, Segmentation fault.
        0x10bc301 in ?? ()
        (gdb) bt
        #0  0x10bc301 in ?? ()
        #1  0x10bc478 in ?? ()
        #2  0x10bca36 in ?? ()
        #3  0x10b470a in ?? ()
        #4  0x10bbb6c in ?? ()
        #5  0x1072ee6 in ?? ()
        #6  0x1072ac0 in ?? ()
        #7  0x8086853 in call_init ()
        #8  0x808698d in _dl_init ()
        #9  0x80774d4 in dl_open_worker ()
        #10 0x80762bf in _dl_catch_error ()
        #11 0x80775dd in _dl_open ()
        #12 0x8051f18 in do_dlopen ()
        #13 0x80762bf in _dl_catch_error ()
        #14 0x8051ed3 in dlerror_run ()
        #15 0x8051f88 in __libc_dlopen ()
        #16 0x805150d in __nss_lookup_function ()
        #17 0x804ef73 in initgroups ()
        #18 0x8048225 in main (argc=1, argv=0x1000ea4) at initgroups.c:12
        #19 0x80486a0 in __libc_start_main ()
        (gdb) quit
        The program is running.  Exit anyway? (y or n) y
        neal@desdemona:~/initgroups (0)$ exit

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