glibc is: glibc-2.9-2.x86_64

The following program aborts with SEGV under circumstances precised below.

#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>

int main()
{
    struct addrinfo * res = 0x0;
    getaddrinfo ("cups", "631", 0x0, & res);
    return 0;
}

nsswitch.conf is set up to look for NIS matches. The yp database answers for this query:

152.81.1.145       hermione.loria.fr hermione serveurcups printserver cups

Note that the failure occurs _only_ for _some_ nis matches (typically those with many aliases).

valgrind says:

==4832== Invalid free() / delete / delete[]
==4832==    at 0x4A0609F: free (vg_replace_malloc.c:323)
==4832==    by 0x5238835: _nss_nis_gethostbyname4_r (nis-hosts.c:537)
==4832==    by 0x3E3C2CD4D5: gaih_inet (getaddrinfo.c:714)
==4832==    by 0x3E3C2CF19C: getaddrinfo (getaddrinfo.c:2154)
==4832==    by 0x4004F3: main (x.c:8)
==4832==  Address 0x4c2f660 is 40 bytes inside a block of size 69 alloc'd
==4832==    at 0x4A0739E: malloc (vg_replace_malloc.c:207)
==4832==    by 0x3E3BA05D5D: yp_match (ypclnt.c:474)
==4832==    by 0x5238739: _nss_nis_gethostbyname4_r (nis-hosts.c:472)
==4832==    by 0x3E3C2CD4D5: gaih_inet (getaddrinfo.c:714)
==4832==    by 0x3E3C2CF19C: getaddrinfo (getaddrinfo.c:2154)
==4832==    by 0x4004F3: main (x.c:8)

Quick inspection shows nothing trivially wrong with the code, at least to my eyes. Stepping the assembly shows that the ``result'' pointer (which eventually goes haywire) is changed by side-effect around the tokenizing call to parse_line.

Prior to parse_line, one has:

3: *$1 = 0x602be0 "152.81.1.145\thermione.loria.fr hermione serveurcups printserver cups"

and so, afterwards, result is changed to point to the position of ``serveurcups'' above.

I'm mildly suspecting gcc miscompilation, but I haven't delved into what parse_line exactly does.


E.