Module: wine Branch: master Commit: 36c3a51d6abbdba4054e02c2a10b9fd38f8a3d5d URL: https://gitlab.winehq.org/wine/wine/-/commit/36c3a51d6abbdba4054e02c2a10b9fd...
Author: Fabian Maurer dark.shadow4@web.de Date: Mon Jul 24 17:23:44 2023 +0200
gdiplus: Prevent infinite loops due to floating point inaccuracy.
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=52492
---
dlls/gdiplus/graphicspath.c | 12 +++++++----- dlls/gdiplus/tests/graphicspath.c | 37 +++++++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+), 5 deletions(-)
diff --git a/dlls/gdiplus/graphicspath.c b/dlls/gdiplus/graphicspath.c index 06e17d4b98a..545aaa8441e 100644 --- a/dlls/gdiplus/graphicspath.c +++ b/dlls/gdiplus/graphicspath.c @@ -183,14 +183,16 @@ static BOOL flatten_bezier(path_list_node_t *start, REAL x2, REAL y2, REAL x3, R mp[2].X = (mp[1].X + mp[3].X) / 2.0; mp[2].Y = (mp[1].Y + mp[3].Y) / 2.0;
- /* Is one pair of the new control points equal to the old control points? */ - if ((x2 == mp[0].X && y2 == mp[0].Y && x3 == mp[1].X && y3 == mp[1].Y) || - (x2 == mp[3].X && y2 == mp[3].Y && x3 == mp[4].X && y3 == mp[4].Y)) - continue; - pt = end->pt; pt_st = start->pt;
+ /* Test for closely spaced points that don't need to be flattened + * Also avoids limited-precision errors in flatness check + */ + if((fabs(pt.X - mp[2].X) + fabs(pt.Y - mp[2].Y) + + fabs(pt_st.X - mp[2].X) + fabs(pt_st.Y - mp[2].Y) ) <= flatness * 0.5) + continue; + /* check flatness as a half of distance between middle point and a linearized path * formula for distance point from line for point (x0, y0) and line (x1, y1) (x2, y2) * is defined as (area_triangle / distance_start_end): diff --git a/dlls/gdiplus/tests/graphicspath.c b/dlls/gdiplus/tests/graphicspath.c index 7cbcb51edfc..558eedc147f 100644 --- a/dlls/gdiplus/tests/graphicspath.c +++ b/dlls/gdiplus/tests/graphicspath.c @@ -1253,6 +1253,42 @@ static void test_flatten(void) GdipDeletePath(path); }
+static void test_flatten2(void) +{ + GpStatus status; + GpPath *path; + + status = GdipCreatePath(0, &path); + expect(Ok, status); + status = GdipStartPathFigure(path); + expect(Ok, status); + + /* path seen in the wild that caused a stack overflow */ + status = GdipAddPathArc(path, -136.33, 20.00, 786.00, 786.00, -105.00, 30.00); + expect(Ok, status); + status = GdipAddPathArc(path, 256.67, 413.00, 0.00, 0.00, -75.00, -30.00); + expect(Ok, status); + status = GdipClosePathFigure(path); + expect(Ok, status); + + status = GdipFlattenPath(path, NULL, 1.0); + expect(Ok, status); + + /* path seen in the wild that caused a stack overflow */ + /* same path but redo with the manual points that caused a crash */ + status = GdipResetPath(path); + expect(Ok, status); + status = GdipAddPathBezier(path, 154.950806, 33.391144, 221.586075, 15.536285, 291.747314, 15.536285, 358.382568, 33.391144); + expect(Ok, status); + status = GdipAddPathBezier(path, 256.666809, 412.999512, 256.666718, 412.999481, 256.666656, 412.999481, 256.666565, 412.999512); + expect(Ok, status); + status = GdipClosePathFigure(path); + expect(Ok, status); + status = GdipFlattenPath(path, NULL, 1.0); + + GdipDeletePath(path); +} + static path_test_t widenline_path[] = { {5.0, 5.0, PathPointTypeStart, 0, 0}, /*0*/ {50.0, 5.0, PathPointTypeLine, 0, 0}, /*1*/ @@ -1935,6 +1971,7 @@ START_TEST(graphicspath) test_widen_cap(); test_isvisible(); test_empty_rect(); + test_flatten2();
GdiplusShutdown(gdiplusToken); }
-
Alexandre Julliard