[vlc-devel] [PATCH] contrib: ass: Add patch to fix crash on macOS

[Steve Lhomme]

To be more consistent with the existing code you could return "" instead 
of NULL.

On 2019-11-07 0:06, Marvin Scholz wrote:
> Fixes a segfault in libass get_font_file function due to
> insufficient checks of return values.
> ---
>   contrib/src/ass/coretext-errorhandling.patch | 27 ++++++++++++++++++++
>   contrib/src/ass/rules.mak                    |  1 +
>   2 files changed, 28 insertions(+)
>   create mode 100644 contrib/src/ass/coretext-errorhandling.patch
> 
> diff --git a/contrib/src/ass/coretext-errorhandling.patch b/contrib/src/ass/coretext-errorhandling.patch
> new file mode 100644
> index 0000000000..29401e48dc
> --- /dev/null
> +++ b/contrib/src/ass/coretext-errorhandling.patch
> @@ -0,0 +1,27 @@
> +diff --git a/libass/ass_coretext.c b/libass/ass_coretext.c
> +index 59a8a2d..7371f7c 100644
> +--- a/libass/ass_coretext.c
> ++++ b/libass/ass_coretext.c
> +@@ -96,7 +96,13 @@ static bool check_glyph(void *priv, uint32_t code)
> + static char *get_font_file(CTFontDescriptorRef fontd)
> + {
> +     CFURLRef url = CTFontDescriptorCopyAttribute(fontd, kCTFontURLAttribute);
> ++    if (!url)
> ++        return NULL;
> +     CFStringRef path = CFURLCopyFileSystemPath(url, kCFURLPOSIXPathStyle);
> ++    if (!path) {
> ++        SAFE_CFRelease(url);
> ++        return NULL;
> ++    }
> +     char *buffer = cfstr2buf(path);
> +     SAFE_CFRelease(path);
> +     SAFE_CFRelease(url);
> +@@ -133,7 +139,7 @@ static void process_descriptors(ASS_Library *lib, ASS_FontProvider *provider,
> +         int index = -1;
> +
> +         char *path = get_font_file(fontd);
> +-        if (strcmp("", path) == 0) {
> ++        if (!path || strcmp("", path) == 0) {
> +             // skip the font if the URL field in the font descriptor is empty
> +             free(path);
> +             continue;
> diff --git a/contrib/src/ass/rules.mak b/contrib/src/ass/rules.mak
> index 1849987447..364afbad17 100644
> --- a/contrib/src/ass/rules.mak
> +++ b/contrib/src/ass/rules.mak
> @@ -43,6 +43,7 @@ $(TARBALLS)/libass-$(ASS_VERSION).tar.gz:
>   libass: libass-$(ASS_VERSION).tar.gz .sum-ass
>   	$(UNPACK)
>   	$(APPLY) $(SRC)/ass/ass-macosx.patch
> +	$(APPLY) $(SRC)/ass/coretext-errorhandling.patch
>   ifdef HAVE_WIN32
>   	$(APPLY) $(SRC)/ass/use-topendir.patch
>   	$(APPLY) $(SRC)/ass/libass-no-tchar.patch
> -- 
> 2.20.1 (Apple Git-117)
> 
> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel
>