weird glibc bug?? (#0 0x153b94c in strlen () at soinit.c:59)

[Troy Benjegerdes]

I am completely and totally stumped.

I have been seeing various programs (everthing from the installer to scp
to apache) that have seemingly inexplicable segfaults since at least the
first glibc-2.1 was out (6 months ago?)

At first I thought this had been caused by a bug in 'strip', since a new
binutils fixed the problem.

this problem seems to have resurfaced again in recent glibc's.

in it's current incarnation, scp is segfaulting, and when I use gdb, I get
the following backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x153b94c in strlen () at soinit.c:59
soinit.c:59: No such file or directory.
(gdb) bt
#0  0x153b94c in strlen () at soinit.c:59
#1  0x151fda4 in _IO_vfprintf () at vfprintf.c:1554
#2  0x1523304 in buffered_vfprintf (s=0x15fd118, format=0x18047e0 "%s:
%s",
    args=0x7ffff1f0) at vfprintf.c:1747
#3  0x151e2f4 in _IO_vfprintf () at vfprintf.c:1554
#4  0x1803d4c in _SDA2_BASE_ ()
#5  0x18039dc in _SDA2_BASE_ ()
#6  0x18022ac in _SDA2_BASE_ ()
#7  0x1801ac4 in _SDA2_BASE_ ()
#8  0x14fd7d4 in __libc_start_main () at ../sysdeps/powerpc/elf/libc-sta

So, my first thought was that strip was buggy again, so I built scp and
didn't strip it.

It still segfaults when run from the command line. But it gets more
interesting: When run from gdb, the unstripped binary *doesn't* segfault!!

It seems as though depending on where things are aligned in memory either
triggers or masks the problem. I have heard a report that apache works
fine when built with '-g', and segfaults with a screwed up stack when not.
(this normally isn't noticeable with apache, since it occurs when
returning a 'page not found' error)

Someone please tell me I haven't gone of the deep end on this :-/

--------------------------------------------------------------------------
| Troy Benjegerdes    |       troy at microux.com     |    hozer at drgw.net   |
|    Unix is user friendly... You just have to be friendly to it first.  |
| This message composed with 100% free software.    http://www.gnu.org   |
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