Bug#947045: undefined symbol in libpixbufloader-tiff.so: g_uint_checked_mul

[Simon McVittie]

(LTS team: full quote of bug report below)

On Thu, 19 Dec 2019 at 21:41:59 +0000, McIntyre, Vincent (CASS, Marsfield) wrote:
> Dear LTS Maintainer,

If a bug is specific to a LTS package, please report it to the
debian-lts mailing list (I'm sending this mail there to pass the message
on). https://wiki.debian.org/LTS/FAQ#Where_can_bugs_be_reported.3F

Ordinary bug reports via bugs.debian.org do not normally go to the
LTS team.

> I noticed this and thought I should report it.
> 
> ...
> The following packages will be upgraded:
>   libgdk-pixbuf2.0-0 libgdk-pixbuf2.0-common
> 2 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
> Need to get 463 kB of archives.
> After this operation, 2,048 B disk space will be freed.
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> Get:1 http://<internalapprox>:9999/security/ jessie/updates/main libgdk-pixbuf2.0-0 amd64 2.31.1-2+deb8u8 [168 kB]
> Get:2 http://<internalapprox>:9999/security/ jessie/updates/main libgdk-pixbuf2.0-common all 2.31.1-2+deb8u8 [295 kB]
> Fetched 463 kB in 0s (3,072 kB/s)
> Reading changelogs... Done
> (Reading database ... 56214 files and directories currently installed.)
> Preparing to unpack .../libgdk-pixbuf2.0-0_2.31.1-2+deb8u8_amd64.deb ...
> Unpacking libgdk-pixbuf2.0-0:amd64 (2.31.1-2+deb8u8) over (2.31.1-2+deb8u7) ...
> Preparing to unpack .../libgdk-pixbuf2.0-common_2.31.1-2+deb8u8_all.deb ...
> Unpacking libgdk-pixbuf2.0-common (2.31.1-2+deb8u8) over (2.31.1-2+deb8u7) ...
> Setting up libgdk-pixbuf2.0-common (2.31.1-2+deb8u8) ...
> Setting up libgdk-pixbuf2.0-0:amd64 (2.31.1-2+deb8u8) ...
> g_module_open() failed for /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-tiff.so: /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-tiff.so: undefined symbol: g_uint_checked_mul

This looks like an incorrect backport: g_uint_checked_mul() was new in
GLib 2.48, but Debian 8 only had GLib 2.42, so that won't work.

The code path used for g_uint_checked_mul() on gcc >= 5 is implemented
in terms of the __builtin_umul_overflow() compiler builtin, so a backport
of these gdk-pixbuf patches could probably use __builtin_umul_overflow()
directly, or wrap a macro around it to provide a simplified, gcc-specific
version of g_uint_checked_mul().

Beware that the argument order and return are different: the
equivalent of "dest = a * b" is g_uint_checked_mul(&dest, a, b) or
__builtin_umul_overflow(a, b, &dest), and the sense of the boolean
return is reversed (g_uint_checked_mul returns TRUE on success, but
__builtin_umul_overflow returns 0 on success).

> Processing triggers for libc-bin (2.19-18+deb8u10) ...
> [ Rootkit Hunter version 1.4.2 ]
> File updated: searched for 177 files, found 149
> 
> -- System Information:
> Debian Release: 8.11
>   APT prefers oldoldstable
>   APT policy: (990, 'oldoldstable')
> Architecture: amd64 (x86_64)
> 
> Kernel: Linux 3.16.0-10-amd64 (SMP w/4 CPU cores)
> Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8)
> Shell: /bin/sh linked to /bin/dash
> Init: systemd (via /run/systemd/system)
> 
> Versions of packages libgdk-pixbuf2.0-0 depends on:
> ii  libc6                    2.19-18+deb8u10
> ii  libgdk-pixbuf2.0-common  2.31.1-2+deb8u8
> ii  libglib2.0-0             2.42.1-1+deb8u3
> ii  libjasper1               1.900.1-debian1-2.4+deb8u6
> ii  libjpeg62-turbo          1:1.3.1-12+deb8u2
> ii  libpng12-0               1.2.50-2+deb8u3
> ii  libtiff5                 4.0.3-12.3+deb8u10
> ii  libx11-6                 2:1.6.2-3+deb8u2
> ii  multiarch-support        2.19-18+deb8u10
> 
> libgdk-pixbuf2.0-0 recommends no packages.
> 
> libgdk-pixbuf2.0-0 suggests no packages.
> 
> -- no debconf information