From 8dc3b629434ce256f8e6a584c5853ae9b4230c33 Mon Sep 17 00:00:00 2001 From: Adam Jackson Date: Wed, 31 Oct 2012 16:06:51 -0400 Subject: [PATCH 1/2] xlib: Don't crash when swapping a 0-sized glyph malloc(0) needn't return NULL, and on glibc, doesn't. Then we encounter a loop of the form do { ... } while (--c), which doesn't do quite what you were hoping for when c is initially 0. Since there's nothing to swap in this case, just bomb out. Signed-off-by: Adam Jackson --- src/cairo-xlib-render-compositor.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/cairo-xlib-render-compositor.c b/src/cairo-xlib-render-compositor.c index 74c43e9..e38a659 100644 --- a/src/cairo-xlib-render-compositor.c +++ b/src/cairo-xlib-render-compositor.c @@ -1251,6 +1251,9 @@ _cairo_xlib_surface_add_glyph (cairo_xlib_display_t *display, unsigned char *d; unsigned char *new, *n; + if (c == 0) + break; + new = malloc (c); if (!new) { status = _cairo_error (CAIRO_STATUS_NO_MEMORY); @@ -1276,6 +1279,9 @@ _cairo_xlib_surface_add_glyph (cairo_xlib_display_t *display, const uint32_t *d; uint32_t *new, *n; + if (c == 0) + break; + new = malloc (4 * c); if (unlikely (new == NULL)) { status = _cairo_error (CAIRO_STATUS_NO_MEMORY); -- 1.7.12.1