From: Florian Weimer <fweimer@redhat.com>
To: Fengkai Sun via Libc-help <libc-help@sourceware.org>
Cc: Fengkai Sun <qcloud1014@gmail.com>
Subject: Re: Can LD_PRELOAD set different symbol definitions for shared objects and executable?
Date: Tue, 25 May 2021 10:41:43 +0200 [thread overview]
Message-ID: <87eedv19yw.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <CAF6YOcORWWnW8EvCskAmDf3shEBvP8Lo_irBcG7y2+_U0bSZBQ@mail.gmail.com> (Fengkai Sun via Libc-help's message of "Tue, 25 May 2021 10:35:20 +0800")
* Fengkai Sun via Libc-help:
> For example, if I set LD_PRELOAD="./mymalloc.so", then all references to
> malloc will be interposed. There is no way to specify a custom allocator
> only for shared objects(maybe I can make a difference in the source code of
> custom malloc, but that's off topic).
Yes, LD_* variables are captured at startup, and changing their values
later using setenv etc. does not have an impact on the current process.
> I wonder if there is any way to do this, or if I missed out some
> fundamental ideas.
It is possible to do this using the LD_AUDIT framework.
Thanks,
Florian
next prev parent reply other threads:[~2021-05-25 8:41 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-25 2:35 Fengkai Sun
2021-05-25 8:41 ` Florian Weimer [this message]
2021-05-25 16:03 ` Fengkai Sun
2021-05-25 17:50 ` Florian Weimer
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