LD_AUDIT implementation causing process segfaulting

[Jiri Olsa <olsajiri at gmail dot com>]

Hi,

after several unsuccessful attempts to commit a bug (bugzilla report me
the "bug 70907")
I'm writing here, hopefully this is the right place :).

There's a bug in libc in the "sysdeps/i386/dl-trampoline.S". The
_dl_runtime_profile function makes process segfaulting. Under some
conditions the 'edi' and 'esi' registers are restored to wrong values.
IMHO this could be fixed like this:

Index: sysdeps/i386/dl-trampoline.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/dl-trampoline.S,v
retrieving revision 1.2
diff -r1.2 dl-trampoline.S
116d115
<       andl $0xfffffff0, %edi  # Align stack

edi and esi registers are pushed on stack before it is alligned. In case
it is really aligned those registers wont be restored properly. I tried
the fix and it is working for me. I dont know the reason for alligning
the stack here, so hopefully I'm not missing something... :)

I can reproduce this running the /bin/ls with LD_AUDIT set to library
providing the interface to pltexit.

I'm running the 2.4 version, but seems it is an issue in current sources
as well.

regards
Jiri Olsa