Your message dated Tue, 7 Jan 2025 22:20:36 +0100
with message-id <z32apgwphlfag...@aurel32.net>
and subject line Re: Bug#472269: libc6: res_query makes assumptions about the 
alignment of the answer argument
has caused the Debian Bug report #472269,
regarding libc6: res_query makes assumptions about the alignment of the answer 
argument
to be marked as done.

This means that you claim that the problem has been dealt with.
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-- 
472269: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=472269
Debian Bug Tracking System
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--- Begin Message ---
Package: libc6
Version: 2.7-9
Severity: normal

Hi,

  libc6 assumes the answer argument to the res_query function which is of
  type unsigned char * is aligned in such a way it can be cast to HEADER.

  Thus following apparently correct code causes a SIGBUS on sparc:
     #include <stdio.h>

     #include <arpa/nameser.h>
     #include <resolv.h>

     int
     main (int argc, char ** argv) {
       unsigned char padding[3];
       unsigned char answer[1024];

       res_query ("_xmpp-client._tcp.gmail.com", C_IN, T_SRV,
         answer, sizeof(answer));
       return 0;
     }

  Which is obviously quite nasty.

  Sjoerd

-- System Information:
Debian Release: lenny/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.24-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=C, LC_CTYPE=nl_NL (charmap=ISO-8859-1)
Shell: /bin/sh linked to /bin/bash

Versions of packages libc6 depends on:
ii  libgcc1                       1:4.3.0-1  GCC support library

libc6 recommends no packages.

-- debconf information:
  glibc/upgrade: true
  glibc/restart-failed:
  glibc/restart-services:



--- End Message ---
--- Begin Message ---
Version: 2.36-1

Hi Dave,

On 2022-03-22 18:01, John David Anglin wrote:
> Package: libc6
> Followup-For: Bug #472269
> 
> Dear Maintainer,
> 
> I believe this bug is fixed upstream by the following commit:
> 
> commit 05dec22d7be722987ff07aebf9690f6078b3c4e9 (HEAD -> master, 
> origin/master,
> origin/HEAD)
> Author: John David Anglin <dang...@gcc.gnu.org>
> Date:   Tue Mar 22 17:35:54 2022 +0000
> 
>     resolv: Fix unaligned accesses to fields in HEADER struct
> 
>     The structure HEADER is normally aligned to a word boundary but
>     sometimes it needs to be accessed when aligned on a byte boundary.
>     This change defines a new typedef, UHEADER, with alignment 1.
>     It is used to ensure the fields are accessed with byte loads and
>     stores when necessary.
> 
>     V4: Change to res_mkquery.c deleted.  Small whitespace fix.
> 
>     V5: Move UHEADER typedef to resolv/resolv-internal.h.  Replace all
>     HEADER usage with UHEADER in resolv/res_send.c.
> 
>     Signed-off-by: John David Anglin <dave.ang...@bell.net>
>     Reviewed-by: Adhemerval Zanella  <adhemerval.zane...@linaro.org>
> 

Indeed, thanks for the notice and sorry for the delay. Closing it.

Regards
Aurelien

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurel...@aurel32.net                     http://aurel32.net

--- End Message ---

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