Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 26 Feb 2020 19:38:31 +0100
From: Florian Weimer <>
To: Rich Felker <>
Subject: Re: [PATCH] Add REL_COPY size change detection

* Rich Felker:

> At the very least I think we ought to catch and error on the case
> where def.sym->st_size>sym->st_size, since we can't honor it and
> failure to honor it can produce silent memory corruption. I'm less
> sure about what to do if def.sym->st_size<sym->st-size; this case
> seems safe and might be desirable not to break (I vaguely recall an
> intent that it be ok), but if you think there are reasons it's
> dangerous I'm ok with disallowing it too. I'm having a hard time now
> thinking of a reason it would really help to support that, anyway.

Unfortunately the Mozilla NSS people disagree that size mismatches for
global symbols are an ABI break.  I don't know if this is relevant in
the musl context, but it means that for glibc, we probably can't make
it a hard error.

I want to have better diagnostics for this in glibc, but the current
warning (which is poorly worded at that) is in the
architecture-specific code, and I got side-tracked when I tried to
clean this up the last time.

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.