Bug 20220

Summary:	New recvmsg wrapper in 2.24 missing from libpthread
Product:	glibc	Reporter:	Florian Weimer <fweimer>
Component:	nptl	Assignee:	Not yet assigned to anyone <unassigned>
Status:	RESOLVED FIXED
Severity:	normal	CC:	adhemerval.zanella, drepper.fsp, fweimer, mlichvar
Priority:	P2	Flags:	fweimer: security-
Version:	2.24
Target Milestone:	2.34
See Also:	https://sourceware.org/bugzilla/show_bug.cgi?id=16919
Host:		Target:
Build:		Last reconfirmed:
Bug Depends on:	24741
Bug Blocks:

Description Florian Weimer 2016-06-08 07:15:19 UTC

Currently, libpthread only export recvmsg@GLIBC_2.0, not recvmsg@GLIBC_2.24.  It seems that dlsym can pick this symbol, and applications can call the function with the wrong struct definition as a result.

I suspect a 2.24 version needs to be added to nptl/Versions as well.

Comment 1 Adhemerval Zanella 2016-06-08 14:30:44 UTC

As Joseph pointed out, this seems likely BZ#14932.  My understanding is libpthread provided old {recv,send}msg only for compatibility reasons, new programs should link against newer one on libc and dlsym should return the new version as well.

Comment 2 Florian Weimer 2016-06-08 19:42:15 UTC

Okay, let's treat it as a duplicate.

*** This bug has been marked as a duplicate of bug 14932 ***

Comment 3 Florian Weimer 2019-07-12 13:18:56 UTC

I think we should fix this bug (in recvmsg) by removing the forwarder in libpthread.  The fix for bug 24741 enables that.

Comment 4 Florian Weimer 2021-08-10 10:04:54 UTC

Fixed in glibc 2.34 via:

commit 0cf67de81650dee7ccd72b43b9405842d3509fbe
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Sat Mar 13 20:15:55 2021 -0300

    nptl: Remove recvmsg from libpthread
    
    The libc version is identical and built with same flags.
    
    Checked on x86_64-linux-gnu.