diff options
Diffstat (limited to 'libs/cairo-1.16.0/test/clip-double-free.c')
| -rw-r--r-- | libs/cairo-1.16.0/test/clip-double-free.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/libs/cairo-1.16.0/test/clip-double-free.c b/libs/cairo-1.16.0/test/clip-double-free.c new file mode 100644 index 0000000..74b9a6e --- /dev/null +++ b/libs/cairo-1.16.0/test/clip-double-free.c @@ -0,0 +1,87 @@ +/* + * Copyright © 2011 Uli Schlachter + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Author: Uli Schlachter <psychon@znc.in> + */ + +/* + * This test wants to hit the following double free: + * + * ==10517== Invalid free() / delete / delete[] + * ==10517== at 0x4C268FE: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so) + * ==10517== by 0x87FBE80: _cairo_clip_destroy (cairo-clip.c:136) + * ==10517== by 0x87FE520: _cairo_clip_intersect_boxes.part.1 (cairo-clip-private.h:92) + * ==10517== by 0x87FE79F: _cairo_clip_intersect_rectilinear_path (cairo-clip-boxes.c:266) + * ==10517== by 0x87FC29B: _cairo_clip_intersect_path.part.3 (cairo-clip.c:242) + * ==10517== by 0x8809C3A: _cairo_gstate_clip (cairo-gstate.c:1518) + * ==10517== by 0x8802E40: _cairo_default_context_clip (cairo-default-context.c:1048) + * ==10517== by 0x87FA2C6: cairo_clip (cairo.c:2380) + * ==10517== Address 0x18d44cb0 is 0 bytes inside a block of size 32 free'd + * ==10517== at 0x4C268FE: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so) + * ==10517== by 0x87FE506: _cairo_clip_intersect_boxes.part.1 (cairo-clip-boxes.c:295) + * ==10517== by 0x87FE79F: _cairo_clip_intersect_rectilinear_path (cairo-clip-boxes.c:266) + * ==10517== by 0x87FC29B: _cairo_clip_intersect_path.part.3 (cairo-clip.c:242) + * ==10517== by 0x8809C3A: _cairo_gstate_clip (cairo-gstate.c:1518) + * ==10517== by 0x8802E40: _cairo_default_context_clip (cairo-default-context.c:1048) + * ==10517== by 0x87FA2C6: cairo_clip (cairo.c:2380) + * + * _cairo_clip_intersect_boxes() is called with clip->num_boxes != 0. It then + * calls _cairo_boxes_init_for_array (&clip_boxes, clip->boxes, clip->num_boxes) + * and free (clip->boxes), stealing the clip's boxes, but leaving a dangling + * pointer behind. + * Because this code already intersected the existing boxes and the new ones, we + * now have num_boxes == 0. This means that _cairo_clip_set_all_clipped() gets + * called and tries to free the clip's boxes again. + */ + +#include "cairo-test.h" + +static cairo_test_status_t +draw (cairo_t *cr, int width, int height) +{ + cairo_set_fill_rule (cr, CAIRO_FILL_RULE_EVEN_ODD); + + /* To hit this bug, we first need a clip with + * clip->boxes != clip->embedded_boxes. + */ + cairo_rectangle (cr, 0, 0, 2, 2); + cairo_rectangle (cr, 0, 0, 1, 1); + cairo_clip (cr); + + /* Then we have to intersect this with a rectilinear path which results in + * all clipped. This path must consist of at least two boxes or we will hit + * a different code path. + */ + cairo_rectangle (cr, 10, 10, 2, 2); + cairo_rectangle (cr, 10, 10, 1, 1); + cairo_clip (cr); + + return CAIRO_TEST_SUCCESS; +} + +CAIRO_TEST (clip_double_free, + "Test a double free bug in the clipping code", + "clip", /* keywords */ + NULL, /* requirements */ + 0, 0, + NULL, draw) |