[Crash-utility] CA SEOS module causes heartburn for crash(1)

[Dave Anderson]

"Kurtis D. Rader" wrote:

> On Wed, 2005-10-26 10:32:11, Dave Anderson wrote:
> > I'm deferring this to the IBM guys who deal with s390, SUSE kernels, and
> > whatever dumpfile format this is (LKCD or s390 native?).
>
> Actually I'm pretty confident this is not specific to s390 or SLES. I've
> seen the same thing with a dump form a x86 system which had CA SEOS
> loaded. It's just that in that case crash is able to create the necessary
> memory region because the delta between the addresses is less than 1 GiB
> (due, of course to the much smaller size of zone one). So it is still
> potentially an issue for x86.
>
> > But I'm curious -- where in the crash utliity is an mmap being done?
>
> >From store_module_symbols_v1() -> GETBUF(strbuflen). Where strbuflen is
> calculated as the last module name address minus the first observed
> module address plus BUFSIZE. Is this guaranteed to be correct? The code
> appears to be assuming the module symbol table is ordered by the address of
> the symbol names. Is that guaranteed?

Ok, so it's a malloc() failure.  Anyway, it's calculating symbol name namespace by doing
character pointer arithmetic between the pointer to the first symbol's name string
and the last symbol's name string in the module.  (The BUFSIZE is fluff.)  But AFAICT,
it shouldn't have anything to do with the value of the symbol, but rather the pointers
in the module's string section.  Sorry but, it's been a while since I looked at this code,
much less changed it.  So the only thing I can possibly think of is that somehow
there's a reference to a module name string that's in another module entirely?
What are the "first" and "last" values, and are they both contained within the
module's vmalloc'd data area?

Dave


>
>
> --
> Kurtis D. Rader, Level 3 Linux Support
> ABC Service Center, Linux Change Team
> T/L 775-3714, DID +1 503-578-3714
>
> --
> Crash-utility mailing list
> Crash-utility at redhat.com
> https://www.redhat.com/mailman/listinfo/crash-utility