Subject: [bug#65798] [PATCH gnome-team v2] Cogl: fix double free

From: Liliana Marie Prikler <[email-masked]>
Date: Fri, 08 Sep 2023 06:24:12 +0200

Am Donnerstag, dem 07.09.2023 um 07:36 +0200 schrieb Vivien Kraus:
> * gnu/local.mk (dist_patch_DATA): Add cogl-fix-double-free.patch.
> * gnu/packages/gnome.scm (cogl): Apply cogl-fix-double-free.patch.
> * gnu/packages/patches/cogl-fix-double-free.patch: Avoid freeing the
> dispaly used by a cogl context twice.
display

Usually you do (patch, register, use) in this order, but I can rewrite
the ChangeLog for you easily :)

>  Since the cogl repository is
> read-only, this patch won’t be applied upstream.
This information is not necessary in the ChangeLog.  You could mention
it before that, but I think keeping it in the patch itself is a better
idea.

> ---
>  gnu/local.mk                                  |  1 +
>  gnu/packages/gnome.scm                        |  4 ++-
>  .../patches/cogl-fix-double-free.patch        | 31
> +++++++++++++++++++
>  3 files changed, 35 insertions(+), 1 deletion(-)
>  create mode 100644 gnu/packages/patches/cogl-fix-double-free.patch
> 
> diff --git a/gnu/local.mk b/gnu/local.mk
> index 24fa8117c6..ae36dd49c9 100644
> --- a/gnu/local.mk
> +++ b/gnu/local.mk
> @@ -1024,6 +1024,7 @@ dist_patch_DATA
> =                                         \
>    %D%/packages/patches/clucene-pkgconfig.patch                 \
>    %D%/packages/patches/cmake-curl-certificates-3.24.patch      \
>    %D%/packages/patches/coda-use-system-libs.patch              \
> +  %D%/packages/patches/cogl-fix-double-free.patch              \
>    %D%/packages/patches/collectd-5.11.0-
> noinstallvar.patch              \
>    %D%/packages/patches/combinatorial-blas-awpm.patch           \
>    %D%/packages/patches/combinatorial-blas-io-fix.patch         \
> diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
> index 922d6ba24b..6b824c2832 100644
> --- a/gnu/packages/gnome.scm
> +++ b/gnu/packages/gnome.scm
> @@ -6131,7 +6131,9 @@ (define-public cogl
>                             (version-major+minor version) "/"
>                             "cogl-" version ".tar.xz"))
>         (sha256
> -        (base32
> "0nfph4ai60ncdx7hy6hl1i1cmp761jgnyjfhagzi0iqq36qb41d8"))))
> +        (base32
> "0nfph4ai60ncdx7hy6hl1i1cmp761jgnyjfhagzi0iqq36qb41d8"))
> +       (patches
> +        (search-patches "cogl-fix-double-free.patch"))))
>      ;; NOTE: mutter exports a bundled fork of cogl, so when making
> changes to
>      ;; cogl, corresponding changes may be appropriate in mutter as
> well.
This comment no longer applies to current mutter, for it has diverged
far enough.
>      (build-system gnu-build-system)
> diff --git a/gnu/packages/patches/cogl-fix-double-free.patch
> b/gnu/packages/patches/cogl-fix-double-free.patch
> new file mode 100644
> index 0000000000..7094c4cf02
> --- /dev/null
> +++ b/gnu/packages/patches/cogl-fix-double-free.patch
> @@ -0,0 +1,31 @@
> +From 38d3fda8849ac327b473ac11dfac5499f595b7ac Mon Sep 17 00:00:00
> 2001
> +Message-ID:
> <38d3fda8849ac327b473ac11dfac5499f595b7ac.1694118000.git.vivien@plane
> te-kraus.eu>
> +In-Reply-To: <[email-masked]>
> +References: <[email-masked]>
> +From: Vivien Kraus <[email-masked]>
> +Date: Thu, 7 Sep 2023 22:16:48 +0200
> +Subject: [PATCH 1/1] Prevent double free on context objects
> +
> +The display is unrefed in the context destructor, but not refed in
> the
> +constructor.
> +
> +This targets an archived (read-only) repository.
> +---
> + cogl/cogl-context.c | 1 +
> + 1 file changed, 1 insertion(+)
> +
> +diff --git a/cogl/cogl-context.c b/cogl/cogl-context.c
> +index a7eed29a..22809424 100644
> +--- a/cogl/cogl-context.c
> ++++ b/cogl/cogl-context.c
> +@@ -219,6 +219,7 @@ cogl_context_new (CoglDisplay *display,
> +     }
> + 
> +   context->display = display;
> ++  cogl_object_ref (display);
You can use context->display = cogl_object_ref (display) if it works
like g_object_ref.
> + 
> +   /* This is duplicated data, but it's much more convenient to have
> +      the driver attached to the context and the value is accessed a
> +-- 
> +2.41.0
> +
> 
> base-commit: baf5b0745446dabe8166d860996dc54cfa09db3e
Will see what CI has to say, otherwise LGTM.

Cheers