Bug 91396

Summary:	Memory leak in cairo-script-surface
Product:	cairo	Reporter:	Massimo <sixtysix>
Component:	general	Assignee:	Chris Wilson <chris>
Status:	RESOLVED MOVED	QA Contact:	cairo-bugs mailing list <cairo-bugs>
Severity:	normal
Priority:	medium
Version:	unspecified
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:
Attachments:	plug a memory leak script: Plug a memory leak using recording surfaces and vector glyph

Description Massimo 2015-07-19 14:38:00 UTC

Created attachment 117248 [details]
plug a memory leak

The bug is that in '_emit_recording_surface_pattern' the current cr is
saved on the stack in 'old_cr':

http://cgit.freedesktop.org/cairo/tree/src/cairo-script-surface.c#n1173

if replaying the recording surface 'emit_source' is called it is possible
that the 'current_source' member of surface->cr is finished and in its
place is copied the new source, (for surface_patterns this means that the new
source surface ref count is incremented):

http://cgit.freedesktop.org/cairo/tree/src/cairo-script-surface.c#n1741
    
but exiting the recursion 'old_cr' is assigned/raw-copied onto surface->cr and
current_source is overwritten without the matching ref count decrement.
    
compiling cairo with -fsanitize=address Gcc option and running

(cd test; CAIRO_TEST_TARGET=recording ./cairo-test-suite -f user-font-mask )

the report ends with:
... 
SUMMARY: AddressSanitizer: 7632 byte(s) leaked in 27 allocation(s).

Comment 1 Chris Wilson 2015-07-19 15:08:03 UTC

Created attachment 117249 [details] [review]
script: Plug a memory leak using recording surfaces and vector glyph

Hah, I wrote an almost identical patch!

Comment 2 GitLab Migration User 2018-08-25 13:39:54 UTC

-- GitLab Migration Automatic Message --

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