From: Florian Weimer <fw@deneb.enyo.de>
To: Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org>
Subject: Re: [PATCH] dlsym: Make RTLD_NEXT prefer default version definition [#BZ #14932]
Date: Fri, 20 May 2022 16:22:20 +0200 [thread overview]
Message-ID: <87y1yw2sir.fsf@mid.deneb.enyo.de> (raw)
In-Reply-To: <a8ec872d-1d29-2049-03d6-74d61f4a8d7e@linaro.org> (Adhemerval Zanella via Libc-alpha's message of "Fri, 20 May 2022 08:27:53 -0300")
* Adhemerval Zanella via Libc-alpha:
> On 20/05/2022 05:35, Fangrui Song via Libc-alpha wrote:
>> When the first object providing foo defines both foo@v1 and foo@@v2,
>> dlsym(RTLD_NEXT, "foo") returns foo@v1 while dlsym(RTLD_DEFAULT, "foo")
>> returns foo@@v2. The issue is that RTLD_DEFAULT use the
>> DL_LOOKUP_RETURN_NEWEST flag while RTLD_NEXT doesn't. Fix the RTLD_NEXT
>> branch to use DL_LOOKUP_RETURN_NEWEST.
>
> I am afraid we will need to add a compat dlsym for this change.
My working theory is dlsym with RTLD_NEXT with a versioned symbol is
so buggy that this is not needed. I want to understand the nature of
the bug, and plan to post a write-up.
next prev parent reply other threads:[~2022-05-20 14:22 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-20 8:35 Fangrui Song
2022-05-20 11:27 ` Adhemerval Zanella
2022-05-20 14:22 ` Florian Weimer [this message]
2022-05-22 18:54 ` Fāng-ruì Sòng
2022-05-27 16:59 ` Adhemerval Zanella
2022-05-27 11:03 ` Florian Weimer
2022-05-27 19:24 ` Fangrui Song
2022-05-27 20:32 ` Fangrui Song
2022-05-27 20:38 ` Florian Weimer
2022-05-27 21:03 ` Fangrui Song
2022-05-27 21:15 ` Adhemerval Zanella
2022-05-27 22:04 ` Fangrui Song
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